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  • 1995-1999  (175)
  • 1999  (175)
  • Life and Medical Sciences  (96)
  • gene expression  (79)
  • Nuclear reactions
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Years
  • 1995-1999  (175)
Year
Keywords
  • 1
    Electronic Resource
    Electronic Resource
    Regulation of UCP2 and UCP3 by muscle disuse and physical activity in tetraplegic subjects (1999)
    Springer
    Diabetologia 42 (1999), S. 826-830 
    Details
    ISSN: 1432-0428
    Keywords: Keywords Uncoupling proteins ; exercise ; tetraplegia ; skeletal muscle ; mRNA ; gene expression ; polymerase chain reaction.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Aims/hypothesis. The regulation of uncoupling protein 2 and uncoupling protein 3 gene expression in skeletal muscle has recently been the focus of intense interest. Our aim was to determine expression of uncoupling protein 2 and 3 in skeletal muscle from tetraplegic subjects, a condition representing profound muscle inactivity. Thereafter we determined whether exercise training would modify expression of these genes in skeletal muscle. Methods. mRNA expression of uncoupling protein 2 and 3 was determined using quantitative reverse transcription-polymerase chain-reaction. Results. Expression of uncoupling protein 2 and 3 mRNA was increased in skeletal muscle from tetraplegic compared with able-bodied subjects (3.7-fold p 〈 0.01 and 4.1-fold, p 〈 0.05, respectively). A subgroup of four tetraplegic subjects underwent an 8-week exercise programme consisting of electrically-stimulated leg cycling (ESLC, 7 ESLC sessions/week). This training protocol leads to increases in whole body insulin-stimulated glucose uptake and expression of genes involved in glucose metabolism in skeletal muscle from tetraplegic subjects. After ESLC training, uncoupling protein 2 expression was reduced by 62 % and was similar to that in able-bodied people. Similarly, ESLC training was associated with a reduction of uncoupling protein 3 expression in skeletal muscle from three of four tetraplegic subjects, however, post-exercise levels remained increased compared with able-bodied subjects. Conclusion/interpretation. Tetraplegia is associated with increased mRNA expression of uncoupling protein 2 and 3 in skeletal muscle. Exercise training leads to normalisation of uncoupling protein 2 expression in tetraplegic subjects. Muscle disuse and physical activity appear to be powerful regulators of uncoupling protein 2 and 3 expression in human skeletal muscle. [Diabetologia (1999) 42: 826–830]
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001250051233
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  • 2
    Electronic Resource
    Electronic Resource
    Uncoupling protein-3 gene expression: reduced skeletal muscle mRNA in obese humans during pronounced weight loss (1999)
    Springer
    Diabetologia 42 (1999), S. 302-309 
    Details
    ISSN: 1432-0428
    Keywords: Keywords Obesity ; genetics ; uncoupling protein-3 ; gene expression ; skeletal muscle.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Aims: Uncoupling protein-3 is a member of a protein family that serves to dissipate energy in the form of heat thereby modulating energy expenditure. Alternative processing of uncoupling protein-3 transcripts results in two mRNA species that encode a large and small protein, perhaps differing in functional activity. Since obesity is associated with disrupted energy homeostasis, we measured muscle mRNA expression in morbidly obese and lean subjects. Methods: The two uncoupling protein-3 mRNA species were quantified in muscle tissue using an RNase protection assay. Gene locus effects on mRNA expression were studied by quantitative allele-specific primer extension. Results: In both obese and lean subjects, the mRNA species encoding the small protein isoform was twice as abundant as the mRNA species encoding the large protein isoform. Neither the total uncoupling protein-3 mRNA expression nor the molar abundance ratios of the two mRNA species differed between obese and lean male or female subjects. Women who had lost 37 ± 22 kg of weight in response to dietary restriction and continued a hypocaloric diet displayed lower mRNA than obese (p 〈 0.005) or lean women (p 〈 0.05). Primer extension assays in lean and obese subjects showed similar allelic mRNA abundance in all but one subject studied. Conclusion: Muscle expression of the two uncoupling protein-3 mRNA species is similar in obese and lean people. In obese patients, prolonged hypocaloric diet downregulates uncoupling protein-3 mRNA expression in muscle and can thereby enhance its energy efficiency. Sequence substitutions at the gene locus may only be minor determinants of mRNA expression in muscle tissue. [Diabetologia (1999) 42: 302–309]
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001250051155
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  • 3
    Electronic Resource
    Electronic Resource
    PPARγ, the ultimate thrifty gene (1999)
    Springer
    Diabetologia 42 (1999), S. 1033-1049 
    Details
    ISSN: 1432-0428
    Keywords: Keywords Adipogenesis ; adipose tissue ; cofactors ; gene expression ; fatty acids ; insulin resistance ; nuclear receptors ; prostaglandin ; thiazolidinediones ; Type II diabetes ; transcription.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The peroxisome proliferator-activated receptor gamma (PPARγ) quickly evolved over the last decade from a new orphan receptor to one of the best characterized nuclear receptors. This fast pace in PPARγ research was triggered by two main discoveries. Firstly, that PPARγ was shown to have a key role in adipogenesis and be a master controller of the “thrifty gene response” leading to efficient energy storage. Secondly, the discovery that its synthetic ligands, the thiazolidinediones, are promising insulin sensitizing drugs, which are currently being developed for the treatment of Type II (non-insulin-dependent) diabetes mellitus. More recently this nuclear receptor emerged from a role limited to metabolism (diabetes and obesity) to a power player in general transcriptional control of numerous cellular processes, with implications in cell cycle control, carcinogenesis, inflammation, atherosclerosis and immunomodulation. This widened role of PPARγ will certainly initiate a new flurry of research, which will not only refine our current often partial knowledge of PPARγ but more importantly also establish that this receptor has a definite role as a primary link adapting cellular, tissue and whole body homeostasis to energy stores. [Diabetologia (1999) 42: 1033–1049]
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001250051268
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  • 4
    Electronic Resource
    Electronic Resource
    Characterization of alginate lyase (ALYII) from Pseudomonas sp. OS-ALG-9 expressed in recombinant Escherichia coli (1999)
    Springer
    World journal of microbiology and biotechnology 15 (1999), S. 105-109 
    Details
    ISSN: 1573-0972
    Keywords: Alginate lyase ; gene expression ; polymannuronate lyase ; Pseudomonas sp.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract An alginate lyase named ALYII was purified to homogeneity from Escherichia coli JM109 carrying a recombinant plasmid, pJK26 harbouring the alyII gene from Pseudomonas sp. OS-ALG-9 by column chromatography with DEAE-cellulose, CM-Sephadex C-50, butyl-Toyopearl 650 M and isoelectric focusing. The molecular size of the purified ALYII was estimated to be 79 kDa by SDS-PAGE and its pI was 8.3. The enzyme was most active at pH 7.0 and 30 °C. Its activity was completely inhibited by Hg2+. The enzyme was poly β-D-1, 4-mannuronate-specific rather than β-D-1, 4-guluronate-specific and it showed a promotion effect in alginate degradation by combination with ALY, an another poly β-D-1, 4-mannuronate-specific alginate lyase from the same strain.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008891100111
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  • 5
    Electronic Resource
    Electronic Resource
    Posttranscriptional regulation of urokinase receptor gene expression in human lung carcinoma and mesothelioma cells in vitro (1999)
    Springer
    Molecular and cellular biochemistry 199 (1999), S. 189-200 
    Details
    ISSN: 1573-4919
    Keywords: lung ; cancer ; urokinase ; receptor ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The urokinase-type plasminogen activator (uPA) interacts with its receptor (uPAR) to promote proteolysis as well as cell proliferation and migration. These functions contribute to the pathogenesis of neoplastic growth and invasiveness. Expression of uPAR in tumor extracts also inversely correlates with prognosis in many forms of cancer. In this study, we sought to determine if differences in uPAR expression were distinguishable between cultured human lung carcinoma and malignant mesothelioma subtypes. We also sought to determine if, as in malignant mesothelioma cells, uPAR expression is regulated at the posttranscriptional level in cultured malignant lung carcinoma cells. Using 125I-uPA binding and ligand blotting techniques, uPAR was expressed by phenotypically diverse lung carcinoma cell lines, including the H460, H157 and H1395 non-small cell lines and the H146 small cell lung carcinoma line. Increased uPAR expression was also detected in spindle-shaped (M33K) and epithelioid (M9K and MS-1) malignant mesothelioma cells. Selected mediators, including TGF-β, TNF-α, LPS and PMA, uniformly enhanced uPAR expression in each of the tumor cell lines. Steady state uPAR mRNA expression was determined by RNase protection assay and correlated directly with the changes in cell surface uPAR expression. By gel mobility shift and UV-cross linking assays, a uPAR mRNA binding protein (uPAR mRNABp) implicated in the posttranscriptional control of message stability, was identified in each of the cell lines. Expression of uPAR and its message in cultured lung carcinoma and malignant mesothelioma cells is similarly influenced by effectors present in the tumor microenvironment. Regulation of the uPAR message occurs at the posttranscriptional level in cultured small and non-small cell lung carcinoma cells as well as spindle-shaped and fibrous malignant mesothelioma cell lines. Posttranscriptional regulation of uPAR in all these cells involves the interaction of the uPAR mRNABp with uPAR mRNA, which promotes uPAR mRNA destabilization.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006914800447
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  • 6
    Electronic Resource
    Electronic Resource
    Expression of calcium-binding protein regucalcin mRNA in the cloned rat hepatoma cells (Hr-II-E) is stimulated through Ca2+ signaling factors: Involvement of protein kinase C (1999)
    Springer
    Molecular and cellular biochemistry 198 (1999), S. 101-107 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; Ca2+-binding protein ; protein kinase C ; Ca2+signaling ; gene expression ; H4-II-E hepatoma cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The expression of hepatic Ca2+-binding protein regucalcin in the cloned rat hepatoma cells (H4-II-E) was investigated. The change in regucalcin mRNA levels was analyzed by Northern blotting using rat liver regucalcin complementary DNA (0.9 kb of open reading frame). Regucalcin mRNA was expressed in H4-II-E hepatoma cells. This expression was clearly stimulated in the presence of serum (10% fetal bovine serum). Bay K 8644 (2. 5 × 10-6 M), a Ca2+ channel agonist, significantly stimulated regucalcin mRNA expression in the absence or presence of 10% serum. Dibutyryl cyclic AMP (10-3 M) did not have a stimulatory effect on the regucalcin mRNA expression. The presence of phorbol 12-myristate 13-acetate (PMA; 10-6 M) or estrogen (10-8 M) caused a significant increase in regucalcin mRNA levels in the hepatoma cells cultured in serum-free medium, while insulin (5 × 10-9 M) or dexamethasone (10-6 M) had no effect. Bay K 8644-stimulated regucalcin mRNA expression in the hepatoma cells was completely blocked in the presence of trifluoperazine (10-5 M), an antagonist of calmodulin, or staurosporine (10-7 M), an inhibitor of protein kinase C. The stimulatory effect of PMA was clearly inhibited in the presence of stauroporine. The present study demonstrates that regucalcin mRNA is expressed in the transformed H4-II-E hepatoma cells, and that the expression is stimulated through Ca2+-dependent signaling factors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006996506238
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  • 7
    Electronic Resource
    Electronic Resource
    Expression of calcium-binding protein regucalcin and microsomal Ca2+-ATPase regulation in rat brain: Attenuation with increasing age (1999)
    Springer
    Molecular and cellular biochemistry 200 (1999), S. 43-49 
    Details
    ISSN: 1573-4919
    Keywords: regucalcin ; calcium-binding protein ; gene expression ; Ca2+-ATPase ; brain microsomes ; aging
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract The expression of calcium-binding protein regucalcin and its effect on the microsomal Ca2+-ATPase activity in rat brain tissues was investigated. The expression of regucalcin mRNA was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) analysis in brain tissues using rat regucalcin-specific primers. Regucalcin concentration in the brain tissues was about 5 × 10-9 M as measured using enzyme-linked immunoadsorbent assay (ELISA), and this level was lowered with increasing age (50 weeks old). The presence of regucalcin (10-9 to 10-7 M) in the enzyme reaction mixture caused a significant decrease in Ca2+-ATPase activity in the brain microsomes of young rats (5 weeks old). Meanwhile, the enzyme activity was not significantly altered by the addition of calmodulin (1 or 50 μg/ml), calbindin (1 or 10 μg/ml), and S-100 A protein (5 or 25 μg/ml), which are other Ca2+-binding proteins in rat brain. The effect of regucalcin to inhibit microsomal Ca2+-ATPase activity was weakened in the brain of rats with increasing age (50 weeks old). The present study demonstrates that regucalcin is expressed in the brain, and that it can uniquely inhibit Ca2+-ATPase activity in the brain microsomes of rats. The findings suggest that regucalcin plays a role in the regulation of microsomal Ca2+-ATPase activity in rat brain tissues.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006928402184
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  • 8
    Electronic Resource
    Electronic Resource
    Identification of stretch-responsive genes in pulmonary artery smooth muscle cells by a two arbitrary primer-based mRNA differential display approach (1999)
    Springer
    Molecular and cellular biochemistry 197 (1999), S. 87-96 
    Details
    ISSN: 1573-4919
    Keywords: mechanical stretch ; smooth muscle cells ; differential display ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract Physical forces induce profound changes in cell phenotype, shape and behavior. These changes can occur in vascular structures as a result of pressure overload and their effects can be seen in atherosclerotic vessels in which smooth muscle cells have undergone hyperplastic and hypertrophic changes. At the molecular level, mechanical stimuli are converted into chemical ones and lead to modulation of gene expression and/or the activation of a new repertoire of genes whose encoded proteins help the cells to adapt to their microenvironment. In this study, we have used a two primer-based mRNA differential display technique to identify candidate mechano-responsive genes in pulmonary artery smooth muscle cells. As compared to the original method described by Liang and Pardee, this technique uses two arbitrary primers instead of an anchored oligo(dt) plus an arbitrary primer in the polymerase chain reaction. The chief advantages of these modifications are an increase in the efficiency of the amplification and in the identification of differentially expressed clones. Using this approach, we compared the pattern of expressed genes in cells cultured under static conditions with those in cells that were mechanically stretched (1 Hz) for 24 h in a well-defined in vitro mechanical system. Three candidate genes that showed reproducible differences were chosen for further characterization and cloning. One clone was under expressed in stretched cells and had a DNA sequence with 90% homology to the human fibronectin gene. Two other clones were highly expressed in stretched cells and had a 92% and a 83% sequence homology with human platelet-activating factor (PAF) receptor and rat insulin-like growth factor-I (IGF-I) genes respectively. Northern blot analysis confirmed low levels of fibronectin mRNA transcripts in stretched cells. In contrast, accumulation of PAF receptor mRNA occurred 30 min after mechanical stretch was initiated whereas IGF-I mRNA levels peaked at 8 h. Both mRNA levels were sustained for up to 24 h of mechanical stretching. These results demonstrate the usefulness of the two primer-based mRNA differential display that enabled us to identify and characterize alterations at the level of gene expression among matrix proteins, G-protein coupled receptors and growth factors, each of whose response to mechanical strain is different. A more complete understanding of these responses will provide further insight into the pathologic processes associated with hypertension and atherosclerosis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006966530553
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  • 9
    Electronic Resource
    Electronic Resource
    Stable Transformation of the Intact Cells of Chlorella Kessleri with High Velocity Microprojectiles (1999)
    Springer
    Biologia plantarum 42 (1999), S. 209-216 
    Details
    ISSN: 1573-8264
    Keywords: algae transformation ; bacterial genes ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A transgenic expression system of Chlorella kessleri using the gene for β-glucuronidase (GUS) was developed. Cells of this unicellular green alga were bombarded with the plasmid pBI 121, which bears β-glucuronidase under the control of CaMV 35S promoter and the kanamycin resistant gene. Maximum GUS activity was obtained after 48 h of bombardment using a helium pressure of 900 kPa; GUS activity was then assayed for many generations. The stable transformants were able to grow on kanamycin containing medium after repeated passages between selective and nonselective medium and exhibited GUS activity comparable to that of control cells. Stable transformed cells were confirmed by polymerase chain reaction (PCR) and Southern hybridization of GUS probe with the genomic DNA of C. kessleri.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1002104500953
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  • 10
    Electronic Resource
    Electronic Resource
    Alterations in Protein and Esterase Patterns of Peanut in Response to Salinity Stress (1999)
    Springer
    Biologia plantarum 42 (1999), S. 241-248 
    Details
    ISSN: 1573-8264
    Keywords: Arachis hypogaea ; gene expression ; lipids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The ability of peanut (Arachis hypogaea L.) to grow at high concentrations of NaCl may be due to the alteration in gene expression. SDS-PAGE analysis has revealed that plants grown under NaCl showed induction (127 and 52 kDa) or repression (260 and 38 kDa) in the synthesis of few polypeptides. In addition, nine different esterase isoenzymes were detected in embryos of seeds germinated in 105 mM NaCl, whereas only five of them were detected in the embryos of untreated seeds. On the other hand, in the cotyledons, the esterase pattern was not affected by NaCl concentration. The esterase patterns of both stems and leaves were less influenced by NaCl in comparison to those of roots. The lipid contents, and fresh and dry masses were increased up to 45 mM NaCl and decreased at higher concentrations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1002112702771
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  • 11
    Electronic Resource
    Electronic Resource
    Uncoupling Protein 3: Its Possible Biological Role and Mode of Regulation in Rodents and Humans (1999)
    Springer
    Journal of bioenergetics and biomembranes 31 (1999), S. 467-473 
    Details
    ISSN: 1573-6881
    Keywords: Uncoupling proteins ; fatty acids ; skeletal muscle ; brown adipose tissue ; obesity ; thermogenesis ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Physics
    Notes: Abstract The recently discovered uncoupling protein 3 (UCP3) is highly homologous to the mitochondrialinner membrane protein UCP1, which generates heat by uncoupling the respiratory chainfrom oxidative phosphorylation. The thermogenic function of UCP1 protects against cold andregulates the energy balance in rodents. We review in vitro studies investigating the uncouplingactivity of UCP3 and in vivo studies, which address UCP3 gene expression in brown adiposetissue and skeletal muscle under various metabolic conditions. The data presented are, for themost, consistent with an uncoupling role for UCP3 in regulatory thermogenesis. We alsodiscuss mediators of UCP3 regulation and propose a potential role for intracellular fatty acidsin the mechanism of UCP3 modulation. Finally, we hypothesize a role for UCP3 in themetabolic adaptation of the mitochondria to the degradation of fatty acids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1005448423731
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  • 12
    Electronic Resource
    Electronic Resource
    Tubulin and Glial Fibrillary Acidic Protein Gene Expression in Developing Fetal Human Brain at Midgestation (1999)
    Springer
    Neurochemical research 24 (1999), S. 637-641 
    Details
    ISSN: 1573-6903
    Keywords: Tubulin ; glial fibrillary acidic protein ; gene expression ; human fetal brain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Developmental alterations in the expression of glial fibrillary acidic protein (GFAP) and α-tubulin were examined at the level of mRNA and protein in human fetal brain between weeks 13–23 of gestation. Except for a transient increase at week 15, GFAP expression in the cytoskeletal (CSK) fraction was low until week 17, when it increased steadily to week 23, corresponding to the phase of glial proliferation. The developmental profile of α-tubulin in the CSK fraction displayed a biphasic pattern, with an initial rise between weeks 13–16 coinciding with the early phase of neuroblast multiplication, and a second rise between weeks 17–23 corresponding to the phase of glial proliferation. No significant difference in the spatial distribution of α-tubulin was found in different region of brain but GFAP expression varied with a higher level in cerebellum than that in cerebrum at late midgestation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1021096224161
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  • 13
    Electronic Resource
    Electronic Resource
    The Expression of Several Mitochondrial and Nuclear Genes Encoding the Subunits of Electron Transport Chain Enzyme Complexes, Cytochrome c Oxidase, and NADH Dehydrogenase, in Different Brain Regions in Alzheimer's Disease (1999)
    Springer
    Neurochemical research 24 (1999), S. 767-774 
    Details
    ISSN: 1573-6903
    Keywords: Alzheimer's disease ; gene expression ; cytochrome c oxidase: NADH dehydrogenase ; mRNA ; RT PCR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In this study, changes of the expression of two mitochondrial and two nuclear genes encoding the subunits of cytochrome c oxidase (CO) and NADH dehydrogenase (ND) were studied in the hippocampus, inferior parietal lobule, and cerebellum of 10 Alzheimer's disease (AD) and 10 age-matched control subjects. The altered proportion between CO II and CO IV mRNAs was observed in the AD brain. Changes of the proportion between CO II and CO IV transcripts may contribute to the kinetic perturbation of CO documented in AD. A coordinated decrease of ND4 and ND15 mRNAs was found in the AD hippocampus and inferior parietal lobule, but not in cerebellum. The decrease of ND4 gene expression may lead to the inhibition of normal ubiquinone oxidoreductase activity of ND. This study suggests that changes of the expression of mitochondrial and nuclear genes, encoding parts of ND and CO enzyme complexes, may contribute to alterations of oxidative metabolism in AD.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1020783614031
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  • 14
    Electronic Resource
    Electronic Resource
    Differential sensitivity of human mammary epithelial and breast carcinoma cell lines to curcumin (1999)
    Springer
    Breast cancer research and treatment 54 (1999), S. 269-278 
    Details
    ISSN: 1573-7217
    Keywords: apoptosis ; breast carcinoma ; cell cycle ; curcumin ; cytotoxicity ; gene expression ; RT‐PCR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Curcumin has anti‐inflamatory, antiproliferative, and antitumor effects. To understand the chemopreventive mechanism of curcumin against human malignancies, the cellular and molecular changes induced by this agent in human mammary epithelial (MCF‐10A) and breast carcinoma (MCF‐ 7/TH) cell lines were investigated. The human multidrug‐ resistant breast cancer cell line was 3.5 fold more sensitive to curcumin than the mammary epithelial cell line. Even though both cell lines accumulated a similar amount of curcumin, a significantly higher percentage of apoptotic cells was induced in breast cancer cells compared to a very low percentage of apoptosis in mammary epithelial cells. Incubation of breast cancer cells with 20 and 40 μM curcumin for 24 h induced G2 block and sub‐ G0/G1 cell population, respectively. Curcumin treatment caused a reduction in the expression of Ki67, PCNA, and p53 mRNAs in breast cancer cells. The human mammary epithelial cell line showed a down‐regulation of p21 mRNA and an up‐regulation of Bax mRNA expression with curcumin treatment. The results suggest that apoptosis is involved in the curcumin‐induced inhibition of tumor cell growth, and genes associated with cell proliferation and apoptosis may be playing a role in the chemopreventive action of curcumin. Abbreviations: EGF: epidermal growth factor; D-MEM: Dulbecco' Modified Eagle Medium; EDTA: ethylene diamine tetra‐acetic acid; PBS: phosphate buffered saline; TdT: terminal deoxynucleotidyl transferase; FBS: fetal bovine serum; RT‐PCR: reverse transcription‐polymerase chain reaction; PCNA: proliferating cell nuclear antigen; TNF: tumor necrosis factor; TPA: 12‐tetradecanoyl‐phorbol‐13‐acetate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006170224414
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  • 15
    Electronic Resource
    Electronic Resource
    In-Vitro and In-Vivo Action of Cannabinoids (1999)
    Springer
    Neurochemical research 24 (1999), S. 1233-1240 
    Details
    ISSN: 1573-6903
    Keywords: Anandamide ; AMPA GluR3 receptor subunit ; cannabinoid CB1 receptor ; cAMP ; gene expression ; cannabinoid antagonist ; SR141716A ; Xenopus oocytes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The discovery of endocannabinoids such as anandamide and the wide spread localization of cannabinoid receptors in the brain and peripheral tissues, suggests that the cannabinoid system represents a previously unrecognized ubiquitous net work in the nervous system, whose physiology and function is unfolding. In this study, we tested the hypothesis that some of the actions of anandamide are independent of a cannabinoid receptor mechanism. This was accomplished by the use of cannabinoid agonist and antagonist interaction in an in-vitro and in-vivo test systems. In-vitro, we used Xenopus laevis oocytes expression system and two-voltage clamp technique in combination with differential display polymerase chain reaction to determine whether the differential display of genes following treatment with anandamide may be linked to AMPA glutamate receptor. The differential expression of genes in vivo after the sub-acute administration of anandamide could not be directly linked with the AMPA glutamate receptor. In the voltage clamp studies we investigated the effects of anandamide on recombinant AMPA GluR3 sub-unit currents generated by kainic acid in oocytes expressing the AMPA glutamate receptor. In the in-vitro studies, we present evidence that anandamide inhibited the kainate activated currents in oocytes expressing AMPA glutamate receptor involves cAMP transduction via a cannabinoid receptor independent mechanism. In the in-vivo studies, SR141716A, the CB1 antagonist, induced anxiolysis, that was dependent on the mouse strain used in the anxiety model and blocked the anxiogenic effects of anandamide or methanandamide whereas SR141716A had no effect on the anandamide inhibition of kainate activated currents in-vitro.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1020968922151
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  • 16
    Electronic Resource
    Electronic Resource
    Differential expression of RAB5A in human lung adenocarcinoma cells with different metastasis potential (1999)
    Springer
    Clinical & experimental metastasis 17 (1999), S. 213-219 
    Details
    ISSN: 1573-7276
    Keywords: gene expression ; immunohistochemistry ; mRNA DD ; neoplasia metastasis ; RAB5A
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract For the sake of better understanding the molecular mechanism of neoplasia, we have used the mRNA differential display technique to analyze two human lung adenocarcinoma cell lines, AGZY83-a and Anip973. Anip973 was isolated from AGZY83-a, but manifested much higher metastatic potential than the parent line. We found that a significant differential cDNA fragment in Anip973 was over-expressed, then over-expressed cDNA fragment was cloned and sequenced. It showed that the over-expressed cDNA in Anip973 was RAB5A cDNA. And the RAB5A cDNA sequence was corresponding between the two cells. To determine whether RAB5A may be differentially expressed in the two human lung adenocarcinoma cells at protein level, we further detected RAB5A protein in the two cells by using immunofluorescent method. RAB5A protein was upregulated in highly metastatic Anip973. We also detected the difference in RAB5A gene expression at RNA level in human non-small cell lung carcinoma by RT-PCR. Using immunohistochemical staining, we also examined RAB5A change at protein level in 45 cases human non-small cell lung carcinoma paraffin sections. The results proved the evidence of upregulation of RAB5A in malignant tumor, indicated over-expression of RAB5A gene was correlated with the malignant degree and metastatic potential of lung cancer(χ2 test, p 〈0.01). The RAB5A gene is a member of RAS superfamily, which can transcribe GTP-binding protein that plays an important role in signal transduction of protein trafficking at the cell surface and GDP/GTP cycle in the regulation of endocytotic membrane traffic. Thus our results indicated that over-expression of the RAB5A gene was involved in the process of transformation from AGZY83-a to the higher metastatic cell line Anip973. The result may be a powerful experimental evidence that over-expression of RAB5A gene associated with neoplasia metastasis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006617016451
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  • 17
    Electronic Resource
    Electronic Resource
    Comparison of the Anticancer Effect of Free and HPMA Copolymer-Bound Adriamycin in Human Ovarian Carcinoma Cells (1999)
    Springer
    Pharmaceutical research 16 (1999), S. 986-996 
    Details
    ISSN: 1573-904X
    Keywords: adriamycin ; doxorubicin ; HPMA copolymer ; apoptosis, multidrug resistance ; gene expression ; signal transduction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Purpose. To study peculiarities and the mechanism of the anticancer effect of free and HPMA copolymer-bound ADR in sensitive and resistant human ovarian carcinoma cells. Methods. Sensitive A2780 and ADR resistant A2780/AD cells were exposed to different doses of drugs during 12, 24, 36, 48, 60, and 72 hours. Cell viability, drug accumulation, apoptosis, cellular metabolism, lipid peroxidation, DNA content and gene expression were studied. Results. HPMA copolymer-bound ADR (P(GFLG)-ADR) possessed a comparable cytotoxicity to free ADR when comparison was based on intracellular concentrations. While free ADR up-regulated genes encoding ATP driven efflux pumps (MDR1, MRP), P(GFLG)-ADR overcame existing pumps and down regulated the MRP gene. Free ADR also activated cell metabolism and expression of genes responsible for detoxification and DNA repair. P(GFLG)-ADR down-regulated HSP-70, GSr-π, BUDP, Topo-IIα, β, and TK-1 genes. Apoptosis, lipid peroxidation and DNA damage were significantly higher after exposure to P(GFLG)-ADR, as reflected by simultaneous activation of p53, c-fos in A2780 cells) or c-jun (A2780/AD) signaling pathways and inhibition of the bcl-2 gene. Differences between free ADR and P(GFLG)-ADR increased with the time of incubation and drug concentration. Conclusions. P(GFLG)-ADR overcame drug efflux pumps, more significantly induced apoptosis and lipid peroxidation, inhibited DNA repair, replication, and biosynthesis when compared to free ADR.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018959029186
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  • 18
    Electronic Resource
    Electronic Resource
    Immunological Response in Chronic Fatigue Syndrome Following a Graded Exercise Test to Exhaustion (1999)
    Springer
    Journal of clinical immunology 19 (1999), S. 135-142 
    Details
    ISSN: 1573-2592
    Keywords: Chronic fatigue syndrome ; immunology ; exercise ; sedentary ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This study was conducted to evaluate the immunological response to an exhaustive treadmill exercise test in 20 female chronic fatigue syndrome patients compared to 14 matched sedentary controls. Venipuncture was performed at baseline and 4 min, 1 hr, and 24 hr postexercise. White blood cells were labeled for monoclonal antibody combinations and were quantified by FACsan. Cytokines were assayed utilizing quantitative RT/PCR. No group difference was seen in $$\dot VO_{2_{peak} } $$ (28.6 ± 1.6 vs 30.9 ± 1.2 ml · kg−1 · min−1; P 〉 0.05). However, 24 hr after exercise the patients' fatigue levels were significantly increased (P 〈 0.05). The counts of WBC, CD3+CD8+ cells, CD3+CD4+ cells, T cells, B cells, natural killer cells, and IFN-γ changed across time (P's 〈 0.01). No group differences were seen for any of the immune variables at baseline or after exercise (P's 〉 0.05). The immune response of chronic fatigue syndrome patients to exhaustive exercise is not significantly different from that of healthy nonphysically active controls.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1020510718013
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  • 19
    Electronic Resource
    Electronic Resource
    Cellular distribution of insulin-like growth factor II (IGF-II) mRNA and hormonal regulation of IGF-I and IGF-II mRNA expression in rainbow trout testis (Oncorhynchus mykiss) (1999)
    Springer
    Fish physiology and biochemistry 20 (1999), S. 219-229 
    Details
    ISSN: 1573-5168
    Keywords: fish ; gene expression ; GH ; GtH ; gonad ; growth factors ; RT-PCR ; salmonid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In this study, Northern blot analysis of RNA from trout testis revealed a single transcript of insulin-like growth factor II (IGF-II) around 4.7 kb. The cellular distribution of IGF-II mRNA was studied and quantified in different testicular cells enriched populations by RT-PCR. IGF-II mRNA appears to be expressed in all cellular types tested: spermatogonia A and B, primary spermatocytes, spermatids and secondary spermatocytes and Sertoli cells. A significantly higher expression of IGF-II was found in premeiotic germ cells. The levels of IGF-II mRNA appear to be higher than those of IGF-I in immature trout testis, as judged from the semi-quantitative RT-PCR results. These data suggest that in addition to IGF-I, IGF-II may play a role in testicular physiology in fish. The hormonal regulation of IGF-I and IGF-II gene expression was investigated both in vitro and in vivo using RT-PCR approach. Gonadotropin (GtH) added to testicular explants increased IGF-II mRNA levels but had no effect on IGF-I. No statistically significant effect was observed with androgens. In vivo, GH and pituitary extracts resulted in an 8 fold and 2-3 fold increase in both IGF-I and IGF-II mRNA levels, respectively. Taken together, our study suggests that IGF-I and IGF-II may act as local mediators of GH and GtHs in fish testis. Moreover, our results imply that in fish testicular cells, IGFs are potential paracrine/autocrine regulators inside the spermatogenic compartment and can act directly on germ cells to stimulate their proliferation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007735314871
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  • 20
    Electronic Resource
    Electronic Resource
    Differential gene expression between wheat hybrids and their parental inbreds in seedling leaves (1999)
    Springer
    Euphytica 106 (1999), S. 117-123 
    Details
    ISSN: 1573-5060
    Keywords: differential display ; gene expression ; heterosis ; hybrid wheat ; seedling leaf
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Differential display of mRNA was used to analyze the differences of gene expression in seedling leaves between heterotic hybrid/nonheterotic hybrid and their parental inbreds in order to study the molecular basis of heterosis in wheat. The results indicated that patterns of gene expression in hybrids differ significantly from their parents. Both quantitative and qualitative differences were observed. The quantitative differences include gene over-expression, gene under-expression in hybrid and dominant expression of highly-expressed parental genes in hybrids. The qualitative differences include silencing in hybrids of genes expressed either in male or female parent, and silencing in hybrids of genes expressed in both parents. Expression in hybrid of genes only expressed either in male or female parent was also observed. It was also found that some genes expressed at high level in heterotic hybrid were underexpressed or expressed at low level in nonheterotic hybrid. One differentially expressed cDNA fragment 4B was cloned and sequenced after being confirmed through Northern blot analysis. Homology search in GenBank proved that the cDNA fragment is a new sequence. The selection of primers for differential RNA display in wheat and the relationship between wheat heterosis and alteration of gene expression in hybrids as compared to their parental inbreds were also discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1003548300088
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  • 21
    Electronic Resource
    Electronic Resource
    Effect of Diltiazem on Cardiac Remodeling in Rats Assessed by Doppler Echocardiography and mRNA Expression (1999)
    Springer
    Cardiovascular drugs and therapy 13 (1999), S. 249-258 
    Details
    ISSN: 1573-7241
    Keywords: ventricular remodeling ; myocardial infarction ; diltiazem ; Doppler echocardiography ; gene expression ; cardiac function
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Summary. The purpose of this study was to examine the effect of diltiazem on cardiac dysfunction and the change in cardiac gene expression after myocardial infarction in rats. On the first day after myocardial infarction, rats were randomly assigned to a diltiazem treatment (Dil, n = 7) or an untreated group (MI, n = 8). We then performed Doppler-echocardiographic examinations on the rats and measured their hemodynamics at 4 weeks after myocardial infarction. Following these measurements, their cardiac mRNA was analyzed. Diltiazem decreased the mean aortic pressure and heart rate. Left ventricular end-diastolic pressure (LVEDP) and central venous pressure (CVP) increased to 18 ± 2 mmHg and 5 ± 1 mmHg (P 〈 0.01). Diltiazem reduced LVEDP to 14 ± 1 mmHg (P 〈 0.05), but it did not change CVP. The weight of the right ventricle in MI was significantly larger than in the control rats (control, n = 7, 0.46 ± 0.02 g/kg vs. MI, 0.81 ± 0.06 g/kg; P 〈 0.01). The left ventricular end-diastolic dimension (LVDd) in MI increased to 8.8 ± 0.3 mm (P 〈 0.01, control, 6.1 ± 0.3 mm). Diltiazem prevented an increase in the weight of the right ventricle (0.69 ± 0.03 g/kg, P 〈 0.05) and LVDd (7.7 ±6 0.2 mm, P 〈 0.05 to MI). The rats within MI showed systolic dysfunction, defined by a decreased ejection fraction (control, 67 ± 2% vs. MI, 36 ± 3%, P 〈 0.01), and diastolic dysfunction, defined by the E-wave deceleration rate (control, 13.4 ± 1.6 m/s2 vs. MI, 30.4 ± 3.4 m/s2 P 〈 0.01). Diltiazem significantly prevented systolic and diastolic dysfunction. The increases in β-MHC, ANP, and collagen type I and III mRNAs in the noninfarcted left ventricle and right ventricle were significantly suppressed by treatment with diltiazem. α-Skeletal actin increased in MI, and α-skeletal actin was more increased with Dil. In conclusion, diltiazem prevents cardiac dysfunction and morphological change due to left ventricular remodeling after experimental myocardial infarction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007752310881
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  • 22
    Electronic Resource
    Electronic Resource
    Differentially expressed genes associated with the metastatic phenotype in breast cancer (1999)
    Springer
    Breast cancer research and treatment 55 (1999), S. 125-134 
    Details
    ISSN: 1573-7217
    Keywords: breast cancer ; differential display ; gene expression ; invasion ; metastasis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We have previously shown that human breast carcinoma cells demonstrating an interconverted phenotype, where keratin (epithelial marker) and vimentin (mesenchymal marker) intermediate filaments are both expressed, have an increased ability to invade a basement membrane matrix in vitro. This increase in invasive potential has been demonstrated in MDA‐MB‐231 cells, which constitutively express keratins and vimentin, and in MCF‐7 cells transfected with the mouse vimentin gene (MoVi). However, vimentin expression alone is not sufficient to confer the complete metastatic phenotype in MoVi cells, as determined by orthotopic administration. Thus, in the present study, differential display analysis was utilized to identify genes that are associated with the invasive and/or metastatic phenotype of several human breast cancer cell lines. Forty‐four of 84 PCR fragments were differentially expressed as assessed by Northern hybridization analysis of RNA isolated from MCF‐7, MoVi, and MB‐231 cell lines. Polyadenylated RNA from a panel of poorly invasive, invasive/non‐metastatic, and invasive/metastatic breast carcinoma cell lines was used to differentiate between cell‐specific gene expression and genes associated with the invasive and/or metastatic phenotype(s). We observed that lysyl oxidase and a zinc finger transcription factor were expressed only in the invasive and/or metastatic cell line; whereas, a thiol‐specific antioxidant and a heterochromatin protein were down‐regulated in these cells. In contrast, tissue factor was expressed only in breast carcinoma cell lines having the highest invasive potential. These results suggest that specific genes involved in breast cancer invasion and metastasis can be separated by differential display methodology to elucidate the molecular basis of tumor cell progression.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006188129423
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  • 23
    Electronic Resource
    Electronic Resource
    Identification of Changes in Gene Expression Associated with Minimal Residual Disease (1999)
    Springer
    Cancer and metastasis reviews 18 (1999), S. 3-13 
    Details
    ISSN: 1573-7233
    Keywords: minimal residual disease ; metastasis ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Minimal residual disease (MRD), the tumour burden which remains after a course of treatment that has resulted in clinical remission [1], appears to differ in certain characteristics from the primary tumour population. Certainly the cells which comprise MRD have had to escape from the constraints of the primary tumour mass, invade normal tissue and penetrate small vessels in order to enter the circulation in which they then have had to survive. Such activities are the consequence of the expression of specific proteins and these may well be a reflection of alterations in DNA or RNA levels. Identifying the changes in RNA expression levels between related cell groups exhibiting different phenotypes recently has become a great deal easier as a consequence of developments in analytical procedures such as Differential Display (DD) and Serial Analysis of Gene Expression (SAGE). Application of these procedures to MRD cells recovered from blood, bone marrow or lymph node, should identify novel sequences associated with tumour progression and the development of disseminated disease.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006243917187
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  • 24
    Electronic Resource
    Electronic Resource
    Development of a shuttle vector for screening of strong promoter sequences (1999)
    Springer
    Biotechnology techniques 13 (1999), S. 141-144 
    Details
    ISSN: 1573-6784
    Keywords: promoter probe vector ; gene expression ; transcriptional terminator
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A new promoter probe plasmid, pMOL618, has been specifically designed to be selective for strong promoter sequences. The plasmid contains two origins of replication which allow it to replicate both in Bacillus subtilis and Escherichia coli, as well as an indicator gene which also functions in both backgrounds. The plasmid is therefore useful in the screening of promoter sequences in both organisms. The stringency of the promoter selection is demonstrated using a known strong promoter.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008983208118
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  • 25
    Electronic Resource
    Electronic Resource
    Overexpression of cyclodextrin glycosyltransferase gene from Brevibacillus brevis in Escherichia coli by control of temperature and mannitol concentration (1999)
    Springer
    Biotechnology techniques 13 (1999), S. 765-770 
    Details
    ISSN: 1573-6784
    Keywords: Brevibacillus ; cyclodextrin ; gene expression ; glycosyltransferase ; mannitol ; polyol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Expression of Brevibacillus brevis CD162 cyclodextrin glycosyltransferase (CGTase) gene using pET22b(+) vector in Escherichia coli BL21(DE3) resulted in the formation of inactive inclusion bodies under the usual induction conditions. However, by lowering the induction temperature to 30 °C and/or adding 0.5 M mannitol as an osmolyte, the formation of insoluble aggregates was prevented and about a 34-fold increase (8.51 U ml−1) in biologically active soluble form was achieved after 6 h induction. The active CGTase enzyme was estimated to comprise as much as 24% of the total soluble proteins. In addition, other polyols such as glycerol, erythritol, xylitol, sorbitol, and arabitol showed similar effects with mannitol on the production of active CGTase enzyme.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008909105229
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  • 26
    Electronic Resource
    Electronic Resource
    Biochemical and Molecular Characteristics of the Brain with Developing Cerebral Infarction (1999)
    Springer
    Cellular and molecular neurobiology 19 (1999), S. 93-108 
    Details
    ISSN: 1573-6830
    Keywords: focal cerebral ischemia ; cerebral infarction ; penumbra ; gene expression ; stress response ; inflammatory reaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. We review the biochemical and molecular changes in brain with developing cerebral infarction, based on recent findings in experimental focal cerebral ischemia. 2. Occlusion of a cerebral artery produces focal ischemia with a gradual decline of blood flow, differentiating a severely ischemic core where infarct develops rapidly and an area peripheral to the core where the blood flow reduction is moderate (called penumbra). Neuronal injury in the penumbra is essentially reversible but only for several hours. The penumbra area tolerates a longer duration of ischemia than the core and may be salvageable by pharmacological agents such as glutamate antagonists or prompt reperfusion. 3. Upon reperfusion, brain cells alter their genomic properties so that protein synthesis becomes restricted to a small number of proteins such as stress proteins. Induction of the stress response is considered to be a rescue program to help to mitigate neuronal injury and to endow the cells with resistance to subsequent ischemic stress. The challenge now is to determine how the neuroprotection conferred by prior sublethal ischemia is achieved so that rational strategies can be developed to detect and manipulate gene expression in brain cells vulnerable to ischemia. 4. Expansion of infarction may be caused by an apoptotic mechanism. Investigation of apoptosis may also help in designing novel molecular strategies to prevent ischemic cell death. 5. Ischemia/reperfusion injury is accompanied by inflammatory reactions induced by neutrophils and monocytes/macrophages infiltrated and accumulated in ischemic areas. When the role of the inflammatory/immune systems in ischemic brain injury is revealed, new therapeutic targets and agents will emerge to complement and synergize with pharmacological intervention directed against glutamate and Ca2+ neurotoxicity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006920725663
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  • 27
    Electronic Resource
    Electronic Resource
    Predictivity of an in vitro model for acute and chronic skin irritation (SkinEthic) applied to the testing of topical vehicles (1999)
    Springer
    Cell biology and toxicology 15 (1999), S. 121-135 
    Details
    ISSN: 1573-6822
    Keywords: cytokines ; gene expression ; in vitro human epidermis ; acute and chronic skin irritation ; predictivity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract An in vitro human reconstructed epidermis model (SkinEthic) used for screening acute and chronic skin irritation potential was validated against in vivo data from skin tolerability studies. The irritation potential of sodium lauryl sulfate (SLS), calcipotriol and trans-retinoic acid was investigated. The in vitro epidermis-like model consists of cultures of keratinocytes from human foreskin on a polycarbonate filter. The modulation of cell viability, the release and gene expression of proinflammatory cytokines, interleukins 1α and 8, and morphological changes were evaluated during 3 days as endpoints representative for an inflammatory reaction. The cumulative irritation potential of the topical products was evaluated in a human clinical study by visual scoring and biophysical measurement of inflammatory skin reaction after repeated 24 h applications over 3 weeks under Finn chamber patches. All topical products that were nonirritating in the human study were noncytotoxic and did not induce cytokine expression in the in vitro acute model (day 1 exposure). All irritating controls exhibited specific cell viability and cytokine patterns, which were predictive of the in vivo human data. The ranking of mild to moderate skin irritation potential was based on the lack of cytotoxicity and the presence of cytokine patterns including gene expression specific for each irritant, using the chronic in vitro model (up to 3 days exposure). The human reconstructed epidermis model SkinEthic was shown to be a reliable preclinical tool predicting the irritation potential of topical products. Moreover, it is a useful model in a two-step tiered strategy for screening acute and chronic irritation potential for the selection of vehicles for new topical drugs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007577515215
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  • 28
    Electronic Resource
    Electronic Resource
    Enhancement of bovine growth hormone gene expression by increasing the plasmid copy number (1999)
    Springer
    Biotechnology letters 21 (1999), S. 1-5 
    Details
    ISSN: 1573-6776
    Keywords: bovine growth hormone ; gene expression ; plasmid copy number
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Effect of copy number on the expression of bovine growth hormone gene (bGH) was investigated using the copy number mutants such as pKBJ10, pBJ(Δ tet)10, pUBJ10-1, and pUBJ10 plasmids. The cells harboring plasmids below 84 copies/cell did not produced detectable levels of bGH. When the ColE1 replicon was replaced with the mutated ColE1 replicon originated from pUC19 plasmid, the copy number was increased to about 300 copies/cell and bGH production was enhanced by 11.5% (pUBJ10-1) and 12.3% of total cell protein (pUBJ10). A large amount of mRNA caused by increment of copy number would be needed to overcome some inhibitory threshold and might be an important factor for regulating bGH expression.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1005479907709
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  • 29
    Electronic Resource
    Electronic Resource
    Changes in Gene Expression during the Transition from Compensated Hypertrophy to Heart Failure (1999)
    Springer
    Heart failure reviews 4 (1999), S. 361-378 
    Details
    ISSN: 1573-7322
    Keywords: gene expression ; heart failure ; hypertrophy ; cell signaling ; E-C coupling ; extracellular matrix ; neurohormones ; growth factors ; cytokines ; apoptosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract With the advancement in molecular techniques for characterizing genes and the use of animal models as tools to study heart failure, considerable progress has been made in improving our understanding of the regulation and function of genes associated with heart failure. Studies now indicate that autocrine/paracrine factors including neurohormones such as norepinephrine, angiotensin II, proinflammatory cytokines and peptide growth factors produced locally in the heart may affect myocyte growth and function through intricate signaling mechanisms. While changes in gene expression for the proteins involved in cell signaling may lead to myocyte hypertrophy and/or apoptosis, alteration in calcium homeostasis, excitation-contraction coupling and the extracellular matrix also contribute to systolic and diastolic dysfunction leading to heart failure. Thus, heart failure is a complex process, which involves changes in expression of multiple genes. With the advent of new techniques involving microarray and gene chip technology, it is now possible to define and/or identify sets of genes involved in heart failure. The purpose of this review is to provide an overview of molecular signals, intracellular signaling mechanisms and the changes in gene expression associated with the transition from compensated hypertrophy to failure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009855720081
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  • 30
    Electronic Resource
    Electronic Resource
    Expression of Inhibin/Activin Subunits and Their Receptors and Binding Proteins in Human Preimplantation Embryos (1999)
    Springer
    Journal of assisted reproduction and genetics 16 (1999), S. 73-80 
    Details
    ISSN: 1573-7330
    Keywords: activin ; activin receptors ; semiquantitative RT-PCR ; gene expression ; embryo-endometrium interaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose: Our purpose was to study the role of inhibin/activin during embryogenesis. Methods: Transcripts of inhibin/activin subunits (α, β A , β B ), activin receptors (types I and II), and follistatin were detected by a reverse transcriptase–polymerase chain reaction in human reproductive cells and preembryos cultured alone or co-cultured with human endometrial cells. Results: Transcripts of α, β A , β B subunits were all detected in granulosa luteal cells, but only β A units were detected in endometrial stromal and decidualized cells. In human preimplantation embryos, none of these subunits were detected in embryos from the four-cell to the morula stage and only β A subunits were detectable in blastocyst embryos. Activin receptors were detectable in all of the studied embryos and cells. Transcripts of β A , activin receptors, and follistatin were differentially expressed in human preimplantation embryos cultured in vitro and their expressions were significantly enhanced with the presence of endometrial stromal cells. Conclusions: Our data suggest that there is a possible endometrium–embryo interaction via endometrial activins and preimplantation embryo receptors and that the embryonic expressions of these activins, their receptors, and binding proteins are dependent on embryonic stage.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022564722353
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  • 31
    Electronic Resource
    Electronic Resource
    Isolation of RNA and Protein from Guard Cells of Nicotiana glauca (1999)
    Springer
    Plant molecular biology reporter 17 (1999), S. 371-383 
    Details
    ISSN: 1572-9818
    Keywords: epidermal peel ; extraction ; gene expression ; stomata ; tree tobacco
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Stomatal guard cells are critical for maintenance of plant homeostasis and represent an interesting cell type for studies of leaf cell differentiation and patterning. Here we describe techniques for the isolation of guard cell RNA and protein from blended epidermal peels of Nicotiana glauca. The RNA isolation procedure is a modification of the hot borate method, which is particularly well-suited for recalcitrant tissues. Protein was extracted by disrupting guard cell-enriched epidermis with a French® press. This system offers the following advantages: relatively high yield, low or no contamination by other cell types, fresh tissue as a source of RNA and protein rather than protoplasts, and a plant species that is readily transformable. These techniques will allow for cloning and analysis of genes expressed in guard cells, application of traditional biochemical techniques to guard cell proteins, as well as characterization of genetic manipulation of guard cell function in transgenic plants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007602017492
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  • 32
    Electronic Resource
    Electronic Resource
    Molecular analysis of acclimation to cold (1999)
    Springer
    Plant growth regulation 29 (1999), S. 47-76 
    Details
    ISSN: 1573-5087
    Keywords: cold ; chill ; freezing ; gene expression ; signal transduction pathways
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Temperature is expected to affect all plant processes. Consistent with this, expression of a large number of specific mRNAs and proteins is up-regulated during cold-acclimation. Their possible functions are outlined, encompassing a wide range of processes, some possibly related to other winter stresses besides cold. Some of the cold-responsive sequences are associated with constitutive or stress-related metabolism, others are probably protective, some may influence freezing, and many are of as yet unknown function. While many of the sequences code for intracellular proteins, a significant number code for apoplastic proteins with a variety of possible functions. Transient influx of calcium into the cytosol appears to be a key step in the response to cold, and also to many other stresses and signals. Similarly, the cold-responsive promoter element identified so far is also responsive to drought and salt. However, how cold is sensed, and any cold-specific aspects of the cold signal transduction pathway, are, so far, unknown. What is clear is that, at least in the model plant Arabidopsis thaliana, cold-, desiccation-, salt- and ABA-triggered signal transduction pathways, and possibly others, run partly in parallel and partly intersect. This may be partly explained by a need for an integrated winter-response. The total number of genes which are cold-responsive and the quantity of resources which this implies are used in this way, indicate that many must have a positive role in acclimation. Experiments which modify membrane lipid unsaturation or solute accumulation, achieved by transformation of plants to express exotic or heterologous genes or by other means, confirm that these factors affect chill- or freezing-tolerance. A transgenic test has shown that one cold-up-regulated gene of previously unknown function contributes to freezing-tolerance, but the small effect re-emphasises the probably cumulative nature of the contributions of many cold-up-regulated sequences to acclimation. On the other hand, mutant analysis indicates some genes may make a comparatively larger contribution. Transformation of alfalfa to overexpress a superoxide dismutase gene increased cold-tolerance and drought-resistance and demonstrated that improvements in field-survival of stresses is possible by transgenic means. Over-expression of a transcription factor, CBF1, conferred freezing-tolerance on Arabidopsis, showing that manipulation of the signal transduction pathway could be an important method for modifying cold-tolerance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006291330661
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  • 33
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    Electronic Resource
    Molecular characterization of a gene for alanine aminotransferase from rice (Oryza sativa) (1999)
    Springer
    Plant molecular biology 39 (1999), S. 149-159 
    Details
    ISSN: 1573-5028
    Keywords: alanine aminotransferase ; gene expression ; GUS expression ; promoter
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A cDNA clone encoding alanine aminotransferase (AlaAT) has isolated from randomly sequenced clones derived from a cDNA library of maturing rice seeds by comparison to previously identified genes. The deduced amino acid sequence was 88% and 91% homologous to those of the enzymes from barley and broomcorn millet (Panicum miliaceum), respectively. Using this cDNA as a probe, we isolated and sequenced the corresponding genomic clone. Comparison of the sequences of the cDNA and the genomic gene revealed that the coding region of the gene was interrupted by 14 introns 66 to 1547 bp long. Northern and western blotting analyses showed that the gene was expressed at high levels in developing seeds. When the 5′-flanking region between −930 and +85 from the site of initiation of transcription was fused to a reporter gene for β-glucuronidase (GUS) and then introduced into the rice genome, histochemical staining revealed strong GUS activity in the inner endosperm tissue of developing seeds and weak activity in root tips. Similar tissue-specific expression was also detected by in situ hybridization. These results suggest that AlaAT is involved in nitrogen metabolism during the maturation of rice seed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006156214716
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  • 34
    Electronic Resource
    Electronic Resource
    Differential expression of expansin gene family members during growth and ripening of tomato fruit (1999)
    Springer
    Plant molecular biology 39 (1999), S. 161-169 
    Details
    ISSN: 1573-5028
    Keywords: expansin ; fruit growth ; fruit softening ; gene expression ; Lycopersicon esculentum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract cDNA clones encoding homologues of expansins, a class of cell wall proteins involved in cell wall modification, were isolated from various stages of growing and ripening fruit of tomato (Lycopersicon esculentum). cDNAs derived from five unique expansin genes were obtained, termed tomato Exp3 to Exp7, in addition to the previously described ripening-specific tomato Exp1 (Rose et al. (1997) Proc Natl Acad Sci USA 94: 5955–5960). Deduced amino acid sequences of tomato Exp1, Exp4 and Exp6 were highly related, whereas Exp3, Exp5 and Exp7 were more divergent. Each of the five expansin genes showed a different and characteristic pattern of mRNA expression. mRNA of Exp3 was present throughout fruit growth and ripening, with highest accumulation in green expanding and maturing fruit, and lower, declining levels during ripening. Exp4 mRNA was present only in green expanding fruit, whereas Exp5 mRNA was present in expanding fruit but had highest levels in full-size maturing green fruit and declined during the early stages of ripening. mRNAs from each of these genes were also detected in leaves, stems and flowers but not in roots. Exp6 and Exp7 mRNAs were present at much lower levels than mRNAs of the other expansin genes, and were detected only in expanding or mature green fruit. The results indicate the presence of a large and complex expansin gene family in tomato, and suggest that while the expression of several expansin genes may contribute to green fruit development, only Exp1 mRNA is present at high levels during fruit ripening.
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    URL: http://dx.doi.org/10.1023/A:1006130018931
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    Complexity and expression of the glutamine synthetase multigene family in the amphidiploid crop Brassica napus (1999)
    Springer
    Plant molecular biology 39 (1999), S. 395-405 
    Details
    ISSN: 1573-5028
    Keywords: amphidiploid genome structure ; gene expression ; glutamine synthetase ; multigene family ; nitrogen assimilation ; oilseed rape
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In the amphidiploid genome of oilseed rape (Brassica napus) the diploid ancestral genomes of B. campestris and B. oleracea have been merged. As a result of this crossing event, all gene loci, gene families, or multigene families of the A and C genome types encoding a certain protein are now combined in one plant genome. In the case of the multigene family for glutamine synthetase, the key enzyme of nitrogen assimilation, six different cDNA sequences were isolated from leaf and root specific libraries. One sequence pair (BnGSL1/BnGSL2) was characterized by the presence of amino- terminal transit peptides, a typical feature of all nuclear encoded chloroplast proteins. Two other cDNA pairs (BnGSR1-1/BnGSR1-2 and BnGSR2-1/BnGSR2-2) with very high homology between each other were found in a root specific cDNA library and represent protein subunits for cytosolic glutamine synthetase isoforms. Comparative PCR amplifications of genomic DNA isolated from B. napus, B. campestris and B. oleracea followed by sequence–specific restriction analyses of the PCR products permitted the assignment of the cDNA sequences to either the A genome type (BnGSL1/BnGSR1- 1/BnGSR2-1) or the C genome type (BnGSL2/BnGSR1-2/BnGSR2-2). Consequently, the ancestral GS genes of B. campestris and B. oleracea are expressed simultaneously in oilseed rape. This result was also confirmed by RFLP (restriction fragment length polymorphism) analysis of RT-PCR products. In addition, the different GS genes showed tissue specific expression patterns which are correlated with the state of development of the plant material. Especially for the GS genes encoding the cytosolic GS isoform BnGSR2, a marked increase of expression could be observed after the onset of leaf senescence.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006193717093
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  • 36
    Electronic Resource
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    A transcript encoding translation initiation factor eIF-5A is stored in unfertilized egg cells of maize (1999)
    Springer
    Plant molecular biology 39 (1999), S. 1063-1071 
    Details
    ISSN: 1573-5028
    Keywords: cell cycle ; gene expression ; in vitro fertilization ; maize ; zygote ; embryogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Differential screening of cDNA libraries of unfertilized egg cells and in vitro zygotes of maize resulted in the isolation of more than 50 different genes whose expression is up- or down-regulated after in vitro fertilization (IVF). Amoung these genes, we identified a cDNA encoding the eukaryotic translation initiation factor eIF-5A. This highly conserved factor is thought to be necessary for selective mRNA stabilization and translation. It is also the only known protein that contains the unusual amino acid hypusine which is required for biological activity. High transcript amounts are stored in the egg cell, which is, in terms of metabolism, relatively inactive. Upon fertilization transcript amounts decrease, in contrast to metabolically inactive embryos in which the transcript cannot be detected and transcript levels increase upon germination. The expression pattern during the first embryonic cell cycle is also different from that observed during the somatic cell cycle: egg cells in the G0 phase contain high transcript levels, while arrested suspension cells contain few transcripts. In the somatic cell cycle, eif-5A is strongly induced during the G1 phase and transcripts are continuously degraded during the S, G2 and M phases until new induction during the G1 phase of the next cycle. eif-5A, a member of a small gene family in maize, is expressed in most maize tissues investigated. Based on our results, we suggest that the unfertilized egg cell of maize, although relatively inactive regarding its metabolism, is prepared for selective mRNA translation that is quickly triggered after fertilization. We also suggest that the regulation of eif-5A in the first embryonic cell cycle is different from the somatic cell cycle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006176819213
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  • 37
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    Identification of disease response genes expressed in Gossypium hirsutum upon infection with the wilt pathogen Verticillium dahliae (1999)
    Springer
    Plant molecular biology 40 (1999), S. 289-296 
    Details
    ISSN: 1573-5028
    Keywords: gene expression ; Gossypium hirsutum ; plant defence response ; Verticillium dahliae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Verticillium wilt is a vascular disease of cotton (Gossypium spp.) caused by the fungal pathogen Verticillium dahliae. To begin to understand the molecular mechanisms of the disease response in cotton cultivars that display superior wilt tolerance, such as Gossypium hirsutum cv. Sicala V-1, a cDNA library was constructed with mRNA isolated from root tissue of Sicala V-1, 24 h after inoculation with V. dahliae. The library was screened by a differential screening technique which was successful in identifying differences in gene expression between uninfected and V. dahliae-infected G. hirsutum root tissue. Among the differentially expressed clones, 51% represented up-regulated genes which had the potential to be involved in the defence response of G. hirsutum. The temporal expression patterns of nine suspected defence response genes were examined by northern blot analysis at several time intervals after inoculation with V. dahliae. The rapid increase in mRNA transcripts corresponding to each of these clones upon infection suggests a role for these genes in the defence response of G. hirsutum. Genes not previously associated with the defence response of the cotton plant, such as those for a 14-3-3-like protein and pathogenesis-related (PR) proteins, have been identified together with presumably novel genes, for which a definite function could not be ascribed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006146419544
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  • 38
    Electronic Resource
    Electronic Resource
    Mutation of GT-1 binding sites in the Pr-1A promoter influences the level of inducible gene expression in vivo (1999)
    Springer
    Plant molecular biology 40 (1999), S. 387-396 
    Details
    ISSN: 1573-5028
    Keywords: gene expression ; GT-1 ; PR-1a ; PR proteins ; salicylic acid-induced ; transcription factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Infection of Nicotiana tabacum Samsun NN with tobacco mosaic virus (TMV) results in a hypersensitive plant response and leads to systemic acquired resistance (SAR). The induction of SAR is mediated by the plant hormone salicylic acid (SA) and is accompanied by the induced expression of a number of genes including the pathogenesis-related (PR) gene 1a. Previously, it has been found that TMV infection and SA treatment resulted in a reduction of binding of nuclear protein GT-1 to far-upstream regions (−902 to −656) of the PR-1a gene. To test if GT-1 is a negative regulator of PR-1a gene expression, the effects of mutations in the seven putative GT-1 binding sites in this region were studied in vitro using dimethyl sulfate interference footprinting and band shift assays. This showed that at least one of the seven sites is indeed a GT-1 binding site. However, when tested in transgenic plants, the mutations did not result in constitutive expression of the chimeric PR-1a/GUS transgene, while inducible expression after SA treatment was decreased. The results suggest that binding of GT-1-like proteins to far-upstream PR-1a promoter regions indeed influences gene expression. A possible model for GT-1's mode of action in PR-1a gene expression is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006144505121
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  • 39
    Electronic Resource
    Electronic Resource
    Identification of two chilling-regulated 1-aminocyclopropane- 1-carboxylate synthase genes from citrus (Citrus sinensis Osbeck) fruit (1999)
    Springer
    Plant molecular biology 41 (1999), S. 587-600 
    Details
    ISSN: 1573-5028
    Keywords: ACC synthase ; chilling ; Citrus sinensis ; ethylene ; gene expression ; peel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Diurnal change in the temperature below or above 12.5 °C hastens the degreening of citrus peel and elicits the phytohormone ethylene production in citrus fruit. Ethylene triggers the degradation of chlorophyll and synthesis of carotenoids in citrus peel. To investigate if ethylene is required for the degreening of citrus peel elicited by low temperatures, we studied the chilling-regulated gene expression of ACC synthase, one of the key enzymes catalyzing ethylene biosynthesis. We isolated and characterized a chilling-inducible 1-aminocyclopropane-1-carboxylate synthase (ACC synthase) gene, CS-ACS1, and a chilling-repressible gene, CS-ACS2, from citrus peel. The CS-ACS1 transcript 1.7 kb in length encodes a polypeptide of 483 amino acids (M r 54 115, pI 6.63), whereas the CS-ACS2 transcript of 1.8 kb encodes a polypeptide of 477 amino acids (M r 53 291, pI 6.72). Both genes showed a rapid but transient induction (within 2.4 h) of transcripts upon rewarming after the chilling (4 °C) treatment. After 24 h of incubation at room temperature, CS-ACS1 mRNA diminished to an undetectable level, whereas the CS-ACS2 mRNA regained its basal level of expression attained prior to the chilling treatment. Chilling-induced ethylene production and ACC accumulation were also observed upon rewarming. Both genes were also induced by the wound stress (excision). The protein synthesis inhibitor cycloheximide super-enhances the accumulation of both ACS transcripts at room temperature. Molecular analysis of the 3.3 kb genomic DNA of CS-ACS1 revealed that this gene consists of three introns and four exons. The intron 3 is exceptionally large (1.2 kb) and shares significant homology with mitochondrial DNA, supporting the intron-late theory.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006369016480
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  • 40
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    Electronic Resource
    Identification of genes specifically expressed in cauliflower reproductive meristems. Molecular characterization of BoREM1 (1999)
    Springer
    Plant molecular biology 39 (1999), S. 427-436 
    Details
    ISSN: 1573-5028
    Keywords: reproductive development ; gene expression ; subtractive hybridization ; cauliflower
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Using the meristems of the cauliflower curd as a source of tissue and a series of subtractive hybridizations and amplification reactions, we have constructed a cDNA library highly enriched in cDNAs expressed in reproductive meristems. The analysis of a sample of 250 clones from this library identified 22 cDNA clones corresponding to genes specifically expressed in these cauliflower meristems. Apart from two clones that corresponded to APETALA1, and two other ones showing similarity to different aminoacyl-tRNA synthetases, the remaining clones showed no similarity to any sequence in the databases and may correspond to novel genes. One of these clones, BoREM1, was further characterized and found to correspond to a gene encoding a protein with features of regulatory proteins that follows a expression pattern very similar to the LEAFY transcripts.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006130629100
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  • 41
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    Electronic Resource
    Rice calcium-dependent protein kinase isoforms OsCDPK2 and OsCDPK11 show different responses to light and different expression patterns during seed development (1999)
    Springer
    Plant molecular biology 41 (1999), S. 753-764 
    Details
    ISSN: 1573-5028
    Keywords: calcium-dependent protein kinase ; gene expression ; immunoassays ; light regulation ; rice ; seed development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We investigated the spatial and temporal expression patterns of two rice calcium-dependent protein kinases (CDPKs), OsCDPK2 and OSCDPK11, using isoform-specific antisera. Bands of the expected molecular sizes for OsCDPK2 (59 kDa) and OsCDPK11 (61 kDa) were detected on western blots. OsCDPK2 and OsCDPK11 mRNA and protein levels increased in unison during flower development. However, at the onset of seed development, the protein expression profiles diverged significantly. OsCDPK2 protein was expressed at low levels during early seed development, but increased to high levels that were maintained in later stages (20 days after fertilisation, DAF). Conversely, OsCDPK11 protein levels were high at the beginning of seed development, but fell rapidly from 10 DAF onwards. This decrease in the level of OsCDPK11 protein was associated with the abundant synthesis of a truncated mRNA species. OsCDPK2 expression was also closely associated with light perception. OsCDPK2 protein was barely detectable in green leaves exposed to light, but levels increased sharply when plants were shifted to darkness. Initially, this increase reflected a rapid elevation in the levels of OsCDPK2 mRNA, which was normally located in the mesophyll. Conversely, OsCDPK11 mRNA and protein levels were unaffected by light. These data strongly indicate that two rice CDPK isoforms have different functions in seed development and in response to light in leaves.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006316422400
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  • 42
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    Cloning and characterization of six embryogenesis-associated cDNAs from somatic embryos of Picea glauca and their comparative expression during zygotic embryogenesis (1999)
    Springer
    Plant molecular biology 39 (1999), S. 859-864 
    Details
    ISSN: 1573-5028
    Keywords: embryo-abundant cDNAs ; gene expression ; gymnosperm ; Picea glauca ; somatic embryogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Six somatic embryogenesis-associated cDNAs (PgEMB2, 6, 7, 8, 24 and 34) from white spruce (Picea glauca (Moench) Voss) somatic embryos have been characterized. Transcript accumulation during somatic embryo development and subsequent germination related to these genes, indicated that they were developmentally regulated. The transcripts related to clones PgEMB2, 6, 24 and 34 were also detected during zygotic embryo development, but transcripts of clones PgEMB7 and 8 were not. PgEMB24 had a similar gene expression pattern to spruce Em-like late embryo abundant (lea) gene, but other clones had no similarities in gene expression to either spruce lea-like or storage protein genes. Abscisic acid, a stimulator for spruce somatic embryo maturation, did not obviously affect gene expression corresponding to these cDNAs. The predicted proteins are distinguishable from known LEA proteins based on analyses of hydropathy plots, amino acid compositions and deduced protein structures. The similarities of the spruce cDNAs, and protein sequences predicted from these cDNAs, to other sequence data are described.
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    URL: http://dx.doi.org/10.1023/A:1006146622614
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    Electronic Resource
    Regulation of the chitinase gene expression in suspension-cultured rice cells by N-acetylchitooligosaccharides: differences in the signal transduction pathways leading to the activation of elicitor-responsive genes (1999)
    Springer
    Plant molecular biology 39 (1999), S. 907-914 
    Details
    ISSN: 1573-5028
    Keywords: chitin oligomer ; chitinase ; elicitor ; gene expression ; rice ; signal transduction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Expression patterns of chitinase transcripts induced by N-acetylchitooligosaccharide elicitor were analyzed by northern blot hybridization in order to reveal a signal transduction pathway leading to the activation of class I chitinase genes (Cht-1 and Cht-3), which may play an important role in producing N-acetylchitooligosaccharide elicitor. The transcription level of both genes was enhanced in response to N-acetylchitooligosaccharides larger than pentaose at subnanomolar concentrations. These structure and dose dependencies were consistent not only with those for a 75 kDa high-affinity binding protein for N-acetylchitooligosaccharide elicitor in the plasma membrane, but also with other series of cellular responses including phytoalexin production and the expression of elicitor-responsive genes (EL2, EL3). Therefore, the elicitor signal to evoke these cellular responses including the activation of the chitinase genes could be common and transmitted into cells through the 75 kDa protein. However, the signal transduction pathway for the activation of the chitinase gene appeared to diverge from those for the other elicitor-responsive genes shortly after the signal perception. It was shown that the induction of chitinase expression by N-acetylchitooligosaccharide would require protein phosphorylation, but not de novo protein synthesis. The oxidative burst was demonstrated not to be necessary for transcriptional induction of the all four elicitor-responsive genes (Cht, PAL, EL2, EL3) by N-acetylchitooligosaccharide.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006161802334
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  • 44
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    Differential expression of two spermidine synthase genes during early fruit development and in vegetative tissues of pea (1999)
    Springer
    Plant molecular biology 39 (1999), S. 933-943 
    Details
    ISSN: 1573-5028
    Keywords: cloning ; fruit development ; gene expression ; pea ; polyamine ; spermidine synthase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Two cDNAs from young pea fruits coding for functional spermidine synthases (EC 2.5.1.16) were isolated. The corresponding genes were named psSPDSYN1 and psSPDSYN2. Both cDNAs complemented spe3Δ gene when introduced into the Y480 strain of Saccharomyces cerevisiae, which is a null mutant for the spermidine synthase gene. psSPDSYN1 and psSPDSYN2 are regulated differentially. psSPDSYN1 is up-regulated early after fruit set whereas psSPDSYN2 is expressed later. Spermidine synthase activity was detected in pea ovaries, and correlates with the pattern of expression of psSPDSYN1. In the pea plant, psSPDSYN1 is highly expressed in actively growing tissues, whereas the highest level of psSPDSYN2 mRNA was detected in fully elongated stem.
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    URL: http://dx.doi.org/10.1023/A:1006158819849
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  • 45
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    Electronic Resource
    Diverse range of gene activity during Arabidopsis thaliana leaf senescence includes pathogen-independent induction of defense-related genes (1999)
    Springer
    Plant molecular biology 40 (1999), S. 267-278 
    Details
    ISSN: 1573-5028
    Keywords: defense ; gene expression ; leaf senescence ; nitrilase ; pathogen-free ; salicylic acid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract To determine the range of gene activities associated with leaf senescence, we have identified genes that show preferential transcript accumulation during this developmental stage. The mRNA levels of a diverse array of gene products increases during leaf senescence, including a protease, a ribosomal protein, two cinnamyl alcohol dehydrogenases, a nitrilase and glyoxalase II. Two of the genes identified are known to be pathogen-induced. The senescence specificity of each gene was determined by characterization of transcript accumulation during leaf development and in different tissues. The increased expression of nitrilase in senescent leaves is paralleled by an increase in free indole-3-acetic acid (IAA) levels. Additionally, we have demonstrated that the induction of defense-related genes during leaf senescence is pathogen-independent and that salicylic acid accumulation is not essential for this induction. Our data indicate that the induction of certain genes involved in plant defense responses is a component of the leaf senescence program.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006199932265
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  • 46
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    Electronic Resource
    Characterization and expression of plasma and tonoplast membrane aquaporins in primed seed of Brassica napus during germination under stress conditions (1999)
    Springer
    Plant molecular biology 40 (1999), S. 635-644 
    Details
    ISSN: 1573-5028
    Keywords: aquaporin ; canola ; gene expression ; germination ; priming ; salt and osmotic stresses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Two aquaporin genes were isolated from a cDNA library of canola (Brassica napus L.). The first aquaporin, BnPIP1 of 1094 bp, encoding a putative polypeptide of 287 amino acids with a predicted molecular mass of 30.4 kDa and a pI of 7.8, belongs to the family of plasma membrane intrinsic protein (PIPs) aquaporins. The B. napus aquaporin showed 85–94% identity to the Arabidopsis thaliana PIPs. ABA priming of seed induced high levels of BnPIP1 transcript which remained after subsequent re-drying of the seed. The second aquaporin, Bnγ-TIP2 of 1020 bp, encoded a putative polypeptide of 253 amino acids with a predicted molecular mass of 25.8 kDa and a pI of 5.8. Bnγ-TIP2 showed 83–90% identity to γ-TIP genes from a variety of plant species. Bnγ-TIP2 was expressed only when radicle protrusion occurred in either untreated or primed seeds. Seeds primed with PEG or ABA germinated earlier and showed a higher final percentage of germination than unprimed seed, particularly under salt and osmotic stresses at low temperature. Transcripts of both BnPIP1 and Bnγ-TIP2 genes were present earlier during germination of primed seeds than non-primed seed. From these results, we conclude that BnPIP1 is related to the water transportation required for enzymatic metabolism of storage nutrients at the early stages of canola seed germination whereas Bnγ-TIP2 expression is related to cell growth associated with radicle protrusion. Priming induced the expression of BnPIP1 but had no effect on Bnγ-TIP2.
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    URL: http://dx.doi.org/10.1023/A:1006212216876
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  • 47
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    Expression of two PIP genes in rapidly growing internodes of rice is not primarily controlled by meristem activity or cell expansion (1999)
    Springer
    Plant molecular biology 40 (1999), S. 985-995 
    Details
    ISSN: 1573-5028
    Keywords: aquaporin ; gene expression ; growth ; Oryza sativa ; plasma membrane intrinsic protein (PIP) ; rice
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Membrane intrinsic proteins facilitate movement of small molecules often times functioning as water channels. We have identified two genes from rice which encode proteins with characteristic features of plasma membrane intrinsic proteins (PIP). They possess six membrane-spanning domains, an NPA repeat, overall high sequence homologies and characteristic C- and N-terminal hallmark motifs which allowed assignment of OsPIP1a to the PIP1 subfamily and of OsPIP2a to the PIP2 subfamily. OsPIP1a and OsPIP2a showed similar but not identical expression patterns. The two genes were expressed at higher levels in seedlings than in adult plants and expression in the primary root was regulated by light. In internodes of deepwater rice plants which were induced to grow rapidly by submergence, transcript levels were slightly induced in the intercalary meristem (IM) and slightly reduced in the elongation zone (EZ) after 18 h. In internodes of GA-induced excised stem sections transcript levels transiently declined in the IM and EZ after 1 h and subsequently recovered to elevated levels after 18 h. GA also induced OsPIP expression in non-growing tissue after 18 h. In the IM of submergence-induced stem sections transcript levels remained constitutive. The different growth-promoting treatments showed no direct correlation between growth rate and OsPIP gene expression in dividing or expanding cells. In fact, treatment of excised stem sections with ABA or drought stress induced similar changes in OsPIP expression in the growing zone during the first 6 h as GA did. We conclude that regulation of OsPIP1a and OsPIP2a expression is not primarily controlled by growth. GA-induced growth may however change the water status of cells which in turn results in altered PIP abundance.
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    URL: http://dx.doi.org/10.1023/A:1006265528015
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  • 48
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    Cloning and characterization of a trypsin inhibitor cDNA from amaranth (Amaranthus hypochondriacus) seeds (1999)
    Springer
    Plant molecular biology 41 (1999), S. 15-23 
    Details
    ISSN: 1573-5028
    Keywords: Amaranthus hypochondriacus) ; gene expression ; trypsin inhibitor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We previously isolated and sequenced the major trypsin inhibitor from Amaranthus hypochondriacus seeds. This amaranth trypsin inhibitor (AmTI) is a 69 amino acid protein with high homology to members of the potato-1 inhibitor family. This paper describes the cloning and expression of a cDNA encoding this trypsin inhibitor in various vegetative tissues of the amaranth plant during seed development and imbibition, and investigates the possible induction of AmTI expression by wounding. We obtained a 393 bp cDNA sequence with an open reading frame corresponding to a polypeptide with 76 amino acid residues. With the exception of one residue (Ser-41), the polypeptide agrees with the amino acid sequence previously reported, plus 7 more residues at the N-terminus. These N-terminal residues are thought to be part of the signal used for intracellular sorting. The organ specificity of AmTI gene expression was investigated by northern analysis, showing that mRNA corresponding to AmTI genes was present in stems of plants growing under normal conditions. The kinetics of accumulation of the AmTI-mRNA, protein, and inhibitory activity during seed development and imbibition was determined. AmTI-mRNA accumulation reached a maximum at 14 days after anthesis (daa) and then gradually decreased, being barely detectable 36 daa. The AmTI protein accumulation followed the same profile as the inhibitory activity, both were delayed with respect to the mRNA. The maximum level was observed 22 daa, and then gradually decreased until a steady state was reached as seed maturation proceeded. Upon imbibition, a gradual decrease in AmTI protein and inhibitory activity was shown; however, an AmTI transcript was detected 24 h after imbibition. In contrast to representative members of the potato I family, this inhibitor was not inducible by wounding of leaves.
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    URL: http://dx.doi.org/10.1023/A:1006262106267
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  • 49
    Electronic Resource
    Electronic Resource
    cDNA cloning and characterization of maize phosphoenolpyruvate carboxykinase, a bundle sheath cell-specific enzyme (1999)
    Springer
    Plant molecular biology 41 (1999), S. 301-311 
    Details
    ISSN: 1573-5028
    Keywords: bundle sheath cell ; C4 photosynthesis ; gene expression ; PEP carboxykinase ; prokaryotic expression ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We isolated a full-length cDNA that encodes ATP-dependent phosphoenolpyruvate carboxykinase (EC 4.1.1.49, PCK) from leaves of maize, an NADP-malic enzyme type C4 plant. The mRNA was specifically and rather abundantly expressed in bundle sheath cells in accordance with the recent finding of cell-type-specific localization of PCK protein in maize, which has been detected with antibodies against cucumber PCK protein. The predicted protein had an N-terminal extension, which is characteristic of plant PCKs. The transcript level was much higher in the daytime than at night in 14-day old seedlings. However, in 42-day old plants the extent of diurnal change decreased. The maize PCK was expressed in Escherichia coli with the pET32 plasmid and purified to homogeneity. Through digestion with enterokinase, two types of enzyme were prepared; one with an intact N-terminus and the other lacking its N-terminal 77 amino acid residues due to over-digestion. The truncated protein had about 2-fold higher specific activity than the intact one, and was inhibited by 3-phosphoglycerate (3-PGA) with an I0.5 of 17.5 mM. In contrast, the intact protein was almost insensitive to 3-PGA. These results strongly suggest that the intact N-terminal extension may be involved in the regulation of PCK activity in vivo through some modification such as reversible phosphorylation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006317120460
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  • 50
    Electronic Resource
    Electronic Resource
    Structure and expression of the gene family encoding putrescine N-methyltransferase in Nicotiana tabacum: new clues to the evolutionary origin of cultivated tobacco (1999)
    Springer
    Plant molecular biology 41 (1999), S. 387-401 
    Details
    ISSN: 1573-5028
    Keywords: alkaloids ; gene expression ; Nicotiana tabacum ; nicotine ; putrescine N-methyltransferase ; tobacco gene evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The structure and nuclear genomic organization of the gene family encoding putrescine N-methyltransferase (PMT), the key enzyme in diverting polyamine metabolism towards the biosynthesis of nicotine and related alkaloids, was examined in Nicotiana tabacum. Five genes encoding PMT are present in the N. tabacum genome and all are expressed. The complete coding region and immediate 5′- and 3′- flanking regions were characterized for four members of the gene family and the Exon 1 region of the fifth member of the family was determined. Comparison of the nucleotide and deduced amino acid sequences of the N. tabacum PMT genes with those of presumed progenitor species, N. sylvestris, N. tomentosiformis and N. otophora, revealed that three members of the N. tabacum PMT gene family were most similar to the three genes present in N. sylvestris, whereas the two remaining PMT genes were similar to PMT genes present in N. tomentosiformis and N. otophora genomes, respectively. These data are consistent with an evolutionary origin of N. tabacum resulting from a cross involving N. sylvestris and an introgressed hybrid between N. tomentosiformis and N. otophora. The five PMT genes present in N. tabacum are expressed in the roots of wild-type plants, but not in other organs. The steady-state level of all five PMT transcripts is transiently increased in roots following topping (removal of the floral meristem), although the maximum level of induction for the individual transcripts varies considerably. In contrast to wild-type plants, no increase in PMT transcript levels was observed in a low-alkaloid (nic1nic2) mutant of Burley 21. These data support a role for nic1 and nic2 in the global regulation of alkaloid formation in tobacco and provide for the first time molecular confirmation of the presumed origin of cultivated tobacco.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006342018991
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  • 51
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    Occurrence of five different chromosomal HMG1 proteins in various maize tissues (1999)
    Springer
    Plant molecular biology 41 (1999), S. 351-361 
    Details
    ISSN: 1573-5028
    Keywords: chromatin ; gene expression ; high-mobility-group protein HMG1 ; HMGe ; protein stability ; Zea mays
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The nuclear HMG1 proteins of higher plants are small non-histone proteins that have DNA-bending activity and are considered architectural factors in chromatin. The occurrence of the chromosomal HMG1 proteins, HMGa, HMGc1/2 and HMGd, in various maize tissues was analyzed, and in the course of these studies a novel HMG1 protein, now termed HMGe, was identified. Purification and characterization of HMGe (Mr 13 655) and cloning of the corresponding cDNA revealed that it displays only moderate similarity to other members of the plant HMG1 protein family. The five maize HMG1 proteins could be detected in kernels, leaves, roots and suspension culture cells, indicating that these proteins can be expressed simultaneously and occur relatively ubiquitously. However, the various HMG1 proteins are present in significantly different quantities with HMGa and HMGc1/2 being the most abundant HMG1 proteins in all tissues tested. Furthermore, the relative amounts of the various HMG1 proteins differ among the tissues examined. The HMG1 proteins were found to be relatively stable proteins in vivo, with HMGc1/2, HMGd and HMGe having a half-life of ca. 50 h in cultured cells, while the half-life of the HMGa protein is ca. 65 h. Collectively, these findings are compatible with the concept that the different plant HMG1 proteins might act as general architectural proteins in concert with site-specific factors in the assembly of certain nucleoprotein structures involved in various biological processes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006311121717
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  • 52
    Electronic Resource
    Electronic Resource
    Localization of peroxidase mRNAs in soybean seeds by in situ hybridization (1999)
    Springer
    Plant molecular biology 41 (1999), S. 57-63 
    Details
    ISSN: 1573-5028
    Keywords: embryo ; gene expression ; Glycine max ; oxidoreductase ; seed coat ; testa
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The soybean Ep gene encodes an anionic peroxidase enzyme that accumulates in large amounts in seed coat tissues. We have isolated a second peroxidase gene, Prx2, that is also highly expressed in developing seed coat tissues. Sequence analysis of Prx2 cDNA indicates that this transcript encodes a cationic peroxidase isozyme that is far removed from Ep in peroxidase phylogeny. To determine the expression patterns for these two peroxidases in developing seeds, the abundance and localization of the Ep and Prx2 transcripts were compared by in situ hybridization. Results show the expression of Ep begins in a small number of cells flanking the vascular bundle in the seed coat, spreads to encircle the seed, and then migrates to the hourglass cells as they develop. Expression of Prx2 occurs throughout development in all cell layers of the seed coat, and is also evident in the pericarp and embryo. Nonetheless, the Ep-encoded enzyme accounts for virtually all of the peroxidase activity detected in mature seed coats. The Prx2 enzyme is either insoluble in a catalytically inactive form, or is subject to degradation during seed maturation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006244500951
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  • 53
    Electronic Resource
    Electronic Resource
    The promoter of a Brassica napus lipid transfer protein gene is active in a range of tissues and stimulated by light and viral infection in transgenic Arabidopsis (1999)
    Springer
    Plant molecular biology 41 (1999), S. 75-87 
    Details
    ISSN: 1573-5028
    Keywords: Brassica napus ; cauliflower mosaic virus ; epidermis ; gene expression ; light induction ; lipid transfer protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract cDNA and genomic clones encoding Brassica napus non-specific lipid transfer proteins (LTP) were isolated and sequenced. The encoded amino acid sequences were very similar to those reported previously for LTPs from B. napus and other species. Sequence information indicates that B. napus contains an LTP gene family. The 5′-flanking region of one gene, designated BnLTP, was fused to GUS and the fusion introduced into Arabidopsis. LTP transcripts and BnLTP-Gus expression were present predominantly in the epidermis of leaf and stem, consistent with the hypothesised function of LTPs in the deposition of cuticular or epicuticular waxes. However, GUS activity was detected in other tissues, including lateral root initials, anthers, stigmas and vascular tissues, which may suggest additional functions. LTP transcript levels in B. napus and Arabidopsis and BnLTP-GUS expression in transgenic Arabidopsis were stimulated by blue and red light but not UV-B. BnLTP promoter activity was also stimulated upon viral infection, at a time when the virus had spread systemically. No increase in expression was observed in response to cold or wounding.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006232700835
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  • 54
    Electronic Resource
    Electronic Resource
    Constitutive protein-DNA interactions on the abscisic acid-responsive element before and after developmental activation of the rab28 gene (1999)
    Springer
    Plant molecular biology 41 (1999), S. 529-536 
    Details
    ISSN: 1573-5028
    Keywords: ABRE ; embryogenesis ; G-box ; gene expression ; maize ; protein-DNA interaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Transcription of the rab28 gene from maize is induced in late embryo development and in response to abscisic acid. We have studied the regulation of the activity of the rab28 promoter in embryos. Two abscisic acid-responsive elements (ABREs) were necessary for expression in embryos of transgenic Arabidopsis and in transient transformation in maize embryos. In vivo footprinting showed that there was protein binding to the ABREs and to other cis elements in the promoter in young embryos before expression of rab28. This shows that the rab28 promoter is in an open chromatin structure before developmental activation. The ABREs are important for the induction and have protein binding in young embryos. Nuclear proteins extracted from embryos before activation of rab28 bound to the ABREs in band shift assays. A complex with different mobility was formed between nuclear proteins and the ABREs after induction of rab28 suggesting a modification of the ABRE-binding factor or an exchange of proteins. The footprints on the ABREs were unaltered by induction with abscisic acid or during developmental activation of rab28. These results indicate that constitutive binding of transcription factor(s) on the ABRE is central in embryonic regulation of the rab28 gene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006345113637
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  • 55
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    Auxin and brassinosteroid differentially regulate the expression of three members of the 1-aminocyclopropane-1-carboxylate synthase gene family in mung bean (Vigna radiata L.) (1999)
    Springer
    Plant molecular biology 41 (1999), S. 443-454 
    Details
    ISSN: 1573-5028
    Keywords: 1-aminocyclopropane-1-carboxylate synthase ; auxin ; brassinosteroid ; ethylene ; gene expression ; hypocotyl ; promoter ; transgenic tobacco ; Vigna radiata
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Indole-3-acetic acid (IAA) markedly increased ethylene production by inducing the expression of three 1-aminocyclopropane-1-carboxylate (ACC) synthase cDNAs (pVR-ACS1, pVR-ACS6 and pVR-ACS7) in mung bean hypocotyls. Results from nuclear run-on transcription assay and RNA gel blot studies revealed that all three genes were transcriptionally active displaying unique patterns of induction by IAA and various hormones in etiolated hypocotyls. Particularly, 24-epibrassinolide (BR), an active brassinosteroid, specifically enhanced the expression of VR-ACS7 by a distinct temporal induction mechanism compared to that of IAA. In addition, BR synergistically increased the IAA-induced VR-ACS6 and VR-ACS7 transcript levels, while it effectively abolished both the IAA- and kinetin-induced accumulation of VR-ACS1 mRNA. In light-grown plants, VR-ACS1 was induced by IAA in roots, and VR-ACS6 in epicotyls. IAA- and BR-treatments were not able to increase the VR-ACS7 transcript in the light-grown tissues. These results indicate that the expression of ACC synthase multigene family is regulated by complex hormonal and developmental networks in a gene- and tissue-specific manner in mung bean plants. The VR-ACS7 gene was isolated, and chimeric fusion between the 2.4 kb 5′-upstream region and the β-glucuronidase (GUS) reporter gene was constructed and introduced into Nicotiana tabacum. Analysis of transgenic tobacco plants revealed the VR-ACS7 promoter-driven GUS activity at a highly localized region of the hypocotyl-root junction of control seedlings, while a marked induction of GUS activity was detected only in the hypocotyl region of the IAA-treated transgenic seedlings where rapid cell elongation occurs. Although there was a modest synergistic effect of BR on the IAA-induced GUS activity, BR alone failed to increase the GUS activity, suggesting that induction of VR-ACS7 occurs via separate signaling pathways in response to IAA and BR. A scheme of the multiple regulatory pathways for the expression of ACC synthase multigene family by auxin and BR is presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006372612574
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  • 56
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    Electronic Resource
    A strong constitutive positive element is essential for the ammonium-regulated expression of a soybean gene encoding cytosolic glutamine synthetase (1999)
    Springer
    Plant molecular biology 39 (1999), S. 551-564 
    Details
    ISSN: 1573-5028
    Keywords: ammonium ; gene expression ; glutamine synthetase ; nodules ; positive element ; promoter
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In order to identify important promoter elements controlling the ammonium-regulated expression of the soybean gene GS15 encoding cytosolic glutamine synthetase, a series of 5′ promoter deletions were fused to the GUS reporter gene. To allow the detection of positive and negative regulatory elements, a series of 3′ deletions were fused to a −90 CaMV 35S promoter fragment placed upstream of the GUS gene. Both types of construct were introduced into Lotus corniculatus plants and soybean roots via Agrobacterium rhizogenes-mediated transformation. Both spectrophotometric enzymatic analysis and histochemical localization of GUS activity in roots, root nodules and shoots of transgenic plants revealed that a strong constitutive positive element (SCPE) of 400 bp, located in the promoter distal region is indispensable for the ammonium- regulated expression of GS15. Interestingly, this SCPE was able to direct constitutive expression in both a legume and non- legume background to a level similar to that driven by the CaMV 35S full-length promoter. In addition, results showed that separate proximal elements, located in the first 727 bp relative to the transcription start site, are essential for root- and root nodule-specific expression. This proximal region contains an AAAGAT and two TATTTAT consensus sequences characteristic of nodulin or nodule-enhanced gene promoters. A putative silencer region containing the same TATTTAT consensus sequence was identified between the SCPE and the organ-specific elements. The presence of positive, negative and organ-specific elements together with the three TATTTAT consensus sequences within the promoter strongly suggest that these multiple promoter fragments act in a cooperative manner, depending on the spatial conformation of the DNA for trans-acting factor accessibility.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006169018296
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  • 57
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    Electronic Resource
    Isolation and characterization of mRNAs differentially expressed during ripening of wild strawberry (Fragaria vesca L.) fruits (1999)
    Springer
    Plant molecular biology 39 (1999), S. 629-636 
    Details
    ISSN: 1573-5028
    Keywords: cDNA cloning ; fruit ripening ; gene expression ; non-climacteric fruit ; wild strawberry (Fragaria vesca L.)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Wild strawberry (Fragaria vesca L.) is an attactive model system for studying ripening in non-climacteric fruit, because of its small diploid genome, its short reproductive cycle, and its capacity for transformation. We have isolated eight ripening-induced cDNAs from this species after differential screening of a cDNA library. The predicted polypeptides of seven of the clones exhibit similarity to database protein sequences, including acyl carrier protein, caffeoyl- CoA 3-O-methyltransferase, sesquiterpene cyclase, major latex protein, cystathionine γ-synthase, dehydrin and an auxin- induced gene. A ninth cDNA clone that was constitutively expressed is predicted to encode a metallothionein-like protein. None of these proteins appear to be directly related to events generally associated with ripening such as cell wall metabolism or the accumulation of sugars and pigments, rather, their putative functions are indicative of the wide range of processes upregulated during fruit ripening.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006179928312
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  • 58
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    Electronic Resource
    Enhanced expression and differential inducibility of soybean chalcone synthase genes by supplemental UV-B in dark-grown seedlings (1999)
    Springer
    Plant molecular biology 39 (1999), S. 785-795 
    Details
    ISSN: 1573-5028
    Keywords: UV-B ; soybean ; chalcone synthase ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract By developing gene-specific RT-PCR and using filters to allow transmission down to 290 nm (UV-B+) or blocking all radiation below 320 nm (UV-B−), the effect of UV-B+ and UV-B− light on expression of each of the presently known seven members of soybean chalcone synthase (CHS) gene family in dark-grown seedlings was analyzed. Dark expression was detectable already in 18 h dark-germinating embryos, with progressive increases on successive days, suggesting that chs belongs to a class of genes expressed very early during germination, and that the expression at this stage is either constitutive or induced by non-light-dependent factors present in the seed or made available following imbibition. Exposure of 18 h dark-germinating embryos to UV-B− or to UV-B+ light did not lead to an increase in chs signal. However, the 24 h dark-germinating embryos showed a distinct effect of UV-B+, interestingly coinciding with the stage when the head of seedlings was in the process of being pushed up above ground by stem elongation, suggesting the possibility of a developmental switch modulating the appearance of UV-B response. The response to UV-B− was most prominent in chs1 and almost silent in chs2, while the up-regulation by UV-B+ was most prominent in chs5 and chs6 and much less so in chs2. Interestingly, chs2 was noted to be the only member of the Gmchs gene family devoid of H-box, raising the possibility that the H-box may be a good indicator of the photo-inducibility of a chs gene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006124219945
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  • 59
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    Electronic Resource
    Isolation and molecular characterization of gibberellin-regulated H1 and H2B histone cDNAs in the leaf of the gibberellin-deficient tomato (1999)
    Springer
    Plant molecular biology 39 (1999), S. 883-890 
    Details
    ISSN: 1573-5028
    Keywords: gene expression ; gibberellin ; H1 histone ; H2B histones ; leaf ; Lycopersicon esculentum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract After differential screening we isolated cDNA clones encoding a histone H1 (leH1) and three variants of histone H2B (leH2B-1, -2 and -3) from the gibberellin (GA)-deficient mutant of tomato (gib-1). The deduced polypeptide of leH1 is 271 amino acids long and exhibits the typical tripartite structure of histones H1. The full-length cDNA clone leH2B-1 encodes for a protein of 142 amino residues and shows the tripartite organization of histones H2B. The histones leH1 and leH2B, which show no tissue specificity, are developmentally expressed in the leaf. The mRNA accumulation was higher in organs which contain meristematic tissue and/or which have a high proportion of actively cycling cells. In the leaf of the gib-1 mutant we demonstrated GA-enhanced histone leH1 and leH2B expression which was not observed in the wild type. GAs of the early-13-hydroxylated pathway (GA1 and GA3) caused most enhanced transcription compared to GAs of the early-non-hydroxylation pathway (GA4 and GA9). Application of GA to the mutant increased histone expression that could correlate with enhanced DNA replication in leaf tissue. Increased chromosome replication may indicate that there is a higher rate of cell division and/or increase of endopolyploidy which both may be dependent on cell elongation induced by GAs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006157718263
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  • 60
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    Enzymatic activity and gene expression under water stress of phospholipase D in two cultivars of Vigna unguiculata L.Walp. differing in drought tolerance (1999)
    Springer
    Plant molecular biology 39 (1999), S. 1257-1265 
    Details
    ISSN: 1573-5028
    Keywords: cowpea (Vigna unguiculata L.) ; drought ; gene expression ; lipid degradation ; phospholipase D
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Phospholipase D, a major lipid-degrading enzyme in plants, was studied in two cultivars of Vigna unguiculata L.Walp, differing in their tolerance to drought (cv. EPACE-1, drought-tolerant, and cv. 1183, drought-susceptible). Enzymatic activities, measured with 14C-PC as substrate, increased when plants were submitted to water stress, the increase being much higher in the drought-sensitive cultivar. A 2911 bp cDNA encoding a putative phospholipase D (VuPLD1) was isolated from a cDNA library prepared from V. unguiculata leaves. The deduced amino acid sequence (809 residues) shows 85.5% identity and 91.3% similarity to that of PLD from Ricinus communis. The expression of the VuPLD1 gene in the leaves is differently modulated by water deficit, depending on the intensity of stress and the tolerance or sensitivity of the plants. In the drought-susceptible V. unguiculata cv. 1183, it readily increased under water stress, reaching maximum values at mild water deficit (−1.5 MPa). In the drought-tolerant cv. EPACE-1, VuPLD1 mRNA remained low throughout the whole drought treatment. Dehydration of leaves led to a dramatic increase in transcript level in both cultivars. Changes in protein amounts semi-quantified by immunoblotting correlated well with variations in transcript steady-state level. Taken together, these results showed that phospholipase D in cowpea plants is essentially regulated at the transcriptional level, and that gene expression is strongly stimulated even by moderate water deficit in the drought-sensitive plant. On the contrary, the drought-tolerant plant presents a remarkable stability of PLD gene expression in conditions of water stress.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006165919928
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  • 61
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    Temporal and spatial gene expression of cytochrome B5 during flower and fruit development in olives (1999)
    Springer
    Plant molecular biology 40 (1999), S. 79-90 
    Details
    ISSN: 1573-5028
    Keywords: cytochrome b5 ; fruit and flower development ; gene expression ; in situ hybridisation ; olive
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We report the characterisation of two cytochrome b5 genes and their spatial and temporal patterns of expression during development in olive, Olea europaea. A PCR-generated probe, based on a tobacco cytochrome b5 sequence, was used to isolate two full-length cDNA clones (cytochrome b5-15 and cytochrome b5-38) from a library derived from 13 WAF olive fruits. The cDNAs encoded proteins of 17.0 and 17.7 kDa, which contained all the characteristic motifs of cytochromes b5 from other organisms and exhibited 63% identity and 85% similarity with each other. The olive cytochrome b5-15 cDNA was then used as a probe for more detailed analysis. Southern blotting revealed a gene family of at least 4–6 members while northern blotting and in situ hybridisation showed a highly specific pattern of gene expression. Very low levels of cytochrome b5 mRNA were detected in tissues characterised by high rates of lipid accumulation, such as young expanding leaves, maturing seeds and ripening mesocarp. The cytochrome b5 genes were not induced at 6 °C and their response to ABA was relatively slow compared with fatty acid desaturase genes. In contrast, high levels of cytochrome b5 gene expression were found in young fruits at the pattern formation (globular/heart) stage of embryogenesis and in vascular and transmitting tissues of male and female reproductive organs. The data are consistent with a major role for cytochrome b5 in developmental processes related to plant reproduction in addition to being an electron donor to microsomal desaturases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1026417710320
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  • 62
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    Thiol redox state regulates expression of psbA genes in Synechococcus sp. PCC 7942 (1999)
    Springer
    Plant molecular biology 41 (1999), S. 425-433 
    Details
    ISSN: 1573-5028
    Keywords: D1 protein ; gene expression ; psbA genes ; redox regulation ; Synechococcus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Three psbA genes encode two different forms of the photosystem II reaction centre protein D1 in Synechococcus sp. PCC 7942. The psbAI gene encoding D1 protein form I (D1:1) is mainly expressed under low growth light conditions while the psbAII and psbAIII genes, encoding D1 protein form II (D1:2), are induced under stress conditions (e.g. high light or low temperature). In this paper we show that psbAII/III genes can be rapidly induced even under low growth light conditions by adding the thiol reductant (DTTred) to Synechococcus cell culture, at a concentration that does not affect cell growth or photosynthetic activity. Similar induction of psbAII/III genes was obtained by illuminating the cells with photosystem I light. In both instances psbAI gene down-regulation coincided with the up-regulation of psbAII/III genes. DTTred-induced exchange in transcript pools was subsequently followed by an exchange of D1:1 for D1:2 at the protein level. Thiol oxidants, iodosobenzoic acid or diamide, reverted the effects of DTTred on psbA gene expression. Thiol oxidants and the thiol-modifying agent N-ethylmaleimide also totally prevented high-light induction of psbAII/III genes. These data strongly suggest that the up-regulation of psbAII/III genes that occurs under stress conditions is mediated by production of thiol reductants, whereas the expression of the psbAI gene is sustained by the more oxidizing conditions that prevail during the steady-state growth of cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006347808475
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  • 63
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    Biochemical and molecular aspects of C/N interaction in ectomycorrhizal plants: an update (1999)
    Springer
    Plant and soil 215 (1999), S. 103-113 
    Details
    ISSN: 1573-5036
    Keywords: ammonium assimilation ; Amanita muscaria ; carbon allocation ; ectomycorrhiza ; gene expression ; Picea abies ; sugar transport
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The symbiosis (ectomycorrhiza, ECM) between roots of trees and shrubs of boreal and temperate forest ecosystems and soil fungi is essential for water and nutrient acquisition of the plants. The functionality of ECM is largely dependent on the ability of the host plant to supply photoassimilates to the fungus via the symbiotic interface. Based on sterile in vitro and non-sterile pot experiments, we review data which gives evidence that hexoses are supplied to the fungus by the host plant (mainly glucose and fructose), and that these sugars, at least in part, control development and function of ECM by interfering with fungal gene expression. We further show that any factor which reduces hexose allocation to the host–fungus interface will adversely affect ECM development. As an example, we address the impact of increased supply of nitrogen on the biochemistry of plant–fungus interaction and discuss potential consequences on host performance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1004650324646
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  • 64
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    Optimisation of procedures for microprojectile bombardment of microspore-derived embryos in wheat (1999)
    Springer
    Plant cell, tissue and organ culture 57 (1999), S. 207-210 
    Details
    ISSN: 1573-5044
    Keywords: biolistics ; gene expression ; haploid ; transformation ; Triticum aestivum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Using the PDS-1000/He Biolistic® Particle Delivery System, the microprojectile travel distance, rupture disk pressure and DNA/gold particle concentrations were assessed in order to optimise short and longer-term β-glucuronidase reporter gene expression in microspore-derived embryos of wheat. The effects were also evaluated of using sterile filter paper to support explants and treatment with a high osmoticum medium (0.2 M mannitol/0.2 M sorbitol or 0.4 M maltose). In the optimised procedure, wheat microspore-derived embryos (MDEs), were placed on filter paper and incubated on medium containing 0.4 M maltose, for 4 h pre- and 45 h post-bombardment. Five μl pAHC25 (0.75 mg ml-1 in TE buffer) was precipitated onto 25 μl gold particles (60 mg ml-1 in sterile water), using 20 μl spermidine (0.1 M) and 50 μl CaCl2 (2.5 M). The particles were centrifuged and resuspended in 75 μl absolute ethanol prior to the preparation of 6 macrocarriers. A microprojectile travel distance of 70 mm, a rupture pressure of 1300 p.s.i., and a vacuum of 29′′ Hg were employed. Maltose at 0.4 M in the support medium was the most important factor influencing GUS activity in bombarded tissues. GUS activity, 1 day post-bombardment, reached 52 ± 17 GUS-positive foci/MDE (mean ± s.e.m, n=3), with 17 ± 4 foci/MDE at 15 days, giving a 3.0-fold increase (p〈0.05) compared to expression in MDEs bombarded on medium without a high osmoticum treatment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006384525513
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    Electronic Resource
    Biochemical Responses and Altered Genetic Expression Patterns in Ponderosa Pine (Pinus ponderosa Doug ex P. Laws) Grown Under Elevated CO2 (1999)
    Springer
    Water, air & soil pollution 116 (1999), S. 413-422 
    Details
    ISSN: 1573-2932
    Keywords: Ponderosa pine ; elevated CO2 ; growth ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Biochemical and gene expression changes in response to elevated atmospheric CO2 were investigated in five maternal half-sibling breeding families of Ponderosa pine. Seedlings were grown in a common garden located at Lawrence Livermore National Laboratory, in open-topped chambers (OTC) for two years. Chamber atmospheres were maintained at ambient, ambient + 175 μL L-1, CO2, or ambient + 350 μL L-1CO2. Growth measurements showed significant increases in stem volumes and volume enhancement ratios in three of the five families studied when grown under elevated CO2. Biochemical and gene expression studies were undertaken to gain a mechanistic understanding of these phenotypic responses. Biochemical studies focused on sucrose phosphate synthase (SPS) specific activities at increase CO2 levels. Kinetic evaluations of SPS showed an increase in VMax. Specific SPS probes revealed increases in the transcriptional levels of one SPS gene with exposure to increasing CO2. RT-PCR differential gene displays showed that overall only a small fraction of visualized gene transcripts responded to elevated CO2 (8-10%). There were also significant differences between the gene expression patterns of the different families, some of which correlated with alterations in growth at elevated CO2 levels.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1005207112589
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  • 66
    Electronic Resource
    Electronic Resource
    Novel Technology for Detection of Genomic and Transcriptional Alterations in Pancreatic Cancer (1999)
    Springer
    Annals of oncology 10 (1999), S. 64-68 
    Details
    ISSN: 1569-8041
    Keywords: chromosomal aberrations ; gene expression ; oncogenes ; pancreatic cancer ; tumor suppressor genes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Aim: The present review summarizes our strategies aimed at identifying and characterizing genetic alterations occuring at the transcriptional and chromosomal level in pancreatic cancer. Methods: To study transcriptional alterations we have used a number of techniques including modified versions of differential hybridizations and cDNA-RDA (representational difference analysis). Comparative genomic hybridization (CGH) was used to study chromosomal aberrations occuring in pancreatic cancer tissues. Results: The study of transcriptional alterations led to the identification of more than 500 genes with differential expression in pancreatic cancer. The sum of these alterations represented the first expression profile characteristic for pancreatic tumors. The CGH analysis allowed the identification of a number of chromosomal regions containing putative tumor suppressor genes or oncogenes. These regions are presently being characterized at the molecular level. In a first approach the myb-oncogene was identified as the relevant oncogene of an amplification on 6q occurring in up to 10% of pancreatic cancer patients. Conclusions: Genes isolated in both approaches represent potential new disease genes for pancreatic cancer and are at present being characterized by individual or serial analysis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008392904359
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  • 67
    Electronic Resource
    Electronic Resource
    Effect of Portacaval Anastomosis on Glutamine Synthetase Protein and Gene Expression in Brain, Liver and Skeletal Muscle (1999)
    Springer
    Metabolic brain disease 14 (1999), S. 273-280 
    Details
    ISSN: 1573-7365
    Keywords: glutamine synthetase ; gene expression ; portacaval anastomosis ; hepatic encephalopathy ; liver ; skeletal muscle ; ammonia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The effects of chronic liver insufficiency resulting from end-to-side portacaval anastomosis (PCA) on glutamine synthetase (GS) activities, protein and gene expression were studied in brain, liver and skeletal muscle of male adult rats. Four weeks following PCA, activities of GS in cerebral cortex and cerebellum were reduced by 32% and 37% (p〈0.05) respectively whereas GS activities in muscle were increased by 52% (p〈0.05). GS activities in liver were decreased by up to 90% (p〈0.01), a finding which undoubtedly reflects the loss of GS-rich perivenous hepatocytes following portal-systemic shunting. Immunoblotting techniques revealed no change in GS protein content of brain regions or muscle but a significant loss in liver of PCA rats. GS mRNA determined by semi-quantitative RT-PCR was also significantly decreased in the livers of PCA rats compared to sham-operated controls. These findings demonstrate that PCA results in a loss of GS gene expression in the liver and that brain does not show a compensatory induction of enzyme activity, rendering it particularly sensitive to increases in ammonia in chronic liver failure. The finding of a post-translational increase of GS in muscle following portacaval shunting suggests that, in chronic liver failure, muscle becomes the major organ responsible for the removal of excess blood-borne ammonia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1020741226752
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  • 68
    Electronic Resource
    Electronic Resource
    Differentiation Dependent Activation of the Myelin Genes In Purified Oligodendrocytes is Highly Resistant to Hypoglycemia (1999)
    Springer
    Metabolic brain disease 14 (1999), S. 189-195 
    Details
    ISSN: 1573-7365
    Keywords: Oligodendrocyte cultures ; glucose ; gene expression ; malic enzyme ; membrane synthesis ; myelination ; undernutrition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We have previously demonstrated that the developmental upregulation of myelin-specific genes in mixed glial cultures is strongly attenuated by hypoglycemia. The present study was designed to evaluate the effect of hypoglycemia on differentiation-dependent upregulation of myelin genes in purified oligodendrocyte cultures. The expression of major myelin protein genes, i.e., proteolipid protein (PLP), basic protein (BP) and myelin associated glycoprotein (MAG) were monitored by Northern blot analysis. In control cultures maintained at 6 mg/ml of glucose, the expression of all the genes upregulated rapidly, and plateaued at approximately day 4. A similar pattern of differentiation-dependent upregulation was observed for the gene encoding a lipogenic enzyme, i.e., malic enzyme (ME). In contrast to mixed glial cultures, however, this developmental gene upregulation was not significantly affected by severe hypoglycemia (approximately 0.02 mg/ml). The results indicate that the effect of glucose deprivation on oligodendrocyte genes observed in mixed glial cultures is mediated by other cells. The upregulation of the genes in differentiating oligodendrocytes was accompanied by the production of myelin-related membrane that was isolated by density gradient fractionation. In contrast to the effect on gene expression, this anabolic activity was highly dependent on glucose, as seen from a profound suppression by severe hypoglycemia.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1020614809546
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  • 69
    Electronic Resource
    Electronic Resource
    Increased peroxisomal fatty acid β-oxidation and enhanced expression of peroxisome proliferator-activated receptor-α in diabetic rat liver (1999)
    Springer
    Molecular and cellular biochemistry 194 (1999), S. 227-234 
    Details
    ISSN: 1573-4919
    Keywords: microbodies ; diabetes mellitus ; steroid hormone receptor ; β-oxidation ; gene expression
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract To determine whether the increased fatty acid β-oxidation in the peroxisomes of diabetic rat liver is mediated by a common peroxisome proliferation mechanism, we measured the activation of long-chain (LC) and very long chain (VLC) fatty acids catalyzed by palmitoyl CoA ligase (PAL) and lignoceryl CoA ligase and oxidation of LC (palmitic acid) and VLC (lignoceric acid) fatty acids by isotopic methods. Immunoblot analysis of acyl-CoA oxidase (ACO), and Northern blot analysis of peroxisome proliferator-activated receptor (PPAR-α), ACO, and PAL were also performed. The PAL activity increased in peroxisomes and mitochondria from the liver of diabetic rats by 2.6-fold and 2.1-fold, respectively. The lignoceroyl-CoA ligase activity increased by 2.6-fold in diabetic peroxisomes. Palmitic acid oxidation increased in the diabetic peroxisomes and mitochondria by 2.5-fold and 2.7-fold, respectively, while lignoceric acid oxidation increased by 2.0-fold in the peroxisomes. Immunoreactive ACO protein increased by 2-fold in the diabetic group. The mRNA levels for PPAR-α, ACO and PAL increased 2.9-, 2.8- and 1.6-fold, respectively, in the diabetic group. These results suggest that the increased supply of fatty acids to liver in diabetic state stimulates the expression of PPAR-α and its target genes responsible for the metabolism of fatty acids.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006930513476
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  • 70
    Electronic Resource
    Electronic Resource
    Transcriptional modulation of the human complement factor I gene in Hep G2 cells by protein kinase C activation (1999)
    Springer
    Molecular and cellular biochemistry 201 (1999), S. 111-123 
    Details
    ISSN: 1573-4919
    Keywords: complement factor I ; TPA ; protein kinase C ; gene expression ; Hep G2 cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Abstract This study examined the role of the protein kinase C (PKC) signalling pathway in the regulation of expression of human complement factor I (CFI) gene. The production of CFI by Hep G2 cells was enhanced in a dose- and time-dependent fashion by 12-O-tetradecanoyl-1,2-phorbol 13-acetate (TPA), a potent PKC activator. 4α-phorbol didecanoate, an inactive phorbol ester, had no effect on CFI synthesis. The TPA-dependent increase in CFI secretion was correlated with an increase in CFI mRNA levels. Forskolin, a cAMP-inducing agent, augmented the TPA response. W7, an inhibitor of protein kinase A and genistein, an inhibitor of protein tyrosine kinase(s) both did not prevent the increase in CFI expression mediated by TPA. However, calphostin C, a specific inhibitor of PKC, abolished the TPA-induced increase in CFI mRNA levels. Down regulation of intracellular PKC levels by prior exposure of Hep G2 cells to a high concentration of TPA also blocked the increase in CFI mRNA levels induced by TPA suggesting that the TPA effects were mediated via activation of PKC. mRNA decay studies indicated that the half-life of CFI mRNA in TPA-induced cells was not significantly different from control. Nuclear run-on transcriptional assays on the other hand demonstrated that whereas the CFI gene is transcribed under basal conditions in Hep G2 cells, TPA induced a 3-4 fold increase in the transcription rate of CFI gene in 24 h. The transcription rate of GAPDH gene did not change, indicating that the effects were not general on gene transcription. Transient transfections of Hep G2 cells with chloramphenicol acetyltransferase reporter gene (CAT) constructs containing a series of sequential 5′ deletions of the CFI promoter and CAT assays showed that the sequence between -136 and -130, containing an AP-1 consensus sequence (TGAGTCA) was required for the TPA response. This observation was substantiated by the finding that mutation of this AP-1 site to TttaTCA or TtAtcCA abolished the TPA responsiveness. The enhancement of the activity of transfected chimeric CAT constructs by TPA was abrogated by calphostin C and by pyrrolidine dithiocarbamate (an inhibitor of NF-κB and AP-1 transactivation). These results indicate that TPA regulation of CFI gene requires PKC signalling and is mediated by via a TPA response element (TRE) in the CFI promoter region located at -136/-130 and involves the transactivation of AP-1 and NF-κB transcription factors. We suggest that PKC may be one of the intracellular pathways that control CFI gene expression and that cellular processes (involving growth factors, hormones, cytokines etc.) that activate PKC may upregulate the expression of the CFI gene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007064602321
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  • 71
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    Electronic Resource
    Evidence of Mucin Secretion in Human Lung Adenocarcinoma Cell Lines NCIH650 and NCIH2077 and Effect of Select Secretagogues on Mucin Secretion (1999)
    Springer
    Bioscience reports 19 (1999), S. 473-483 
    Details
    ISSN: 1573-4935
    Keywords: Mucin ; lung cancer ; gene expression ; secretion ; lung adenocarcinoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Mucins comprise an important class of tumor-associated antigens. The objectives of the present study were (a) to establish an in vitro model system using human non-small cell lung adenocarcinoma cell lines NCIH650 and NCIH2077 (b) provide evidence that these cell lines secrete mucin in culture conditions and (c) investigate the effects of select secretagogues on mucin secretion. The cell lines were established in ACL-4 medium containing several growth factors and retinoic acid and 5% fetal calf serum. The high molecular weight glycoconjugates secreted in the culture medium were purified by ammonium sulfate precipitation and Superose 6 and Superose 12 FPLC chromatography. The purified high molecular weight glycoconjugate fraction and the carcinoma cells were shown to have mucin by dot blot, Western blot and immunohistochemical analysis, respectively, using specific antibodies to purified major mucin, HTM-1. Also, incorporation experiments with mucin precursor 3H-glucosamine demonstrated that the cells indeed synthesize high molecular weight mucins. The effects of secretagogues such as, 8-bromocyclic AMP, ionomycin, phorbol-12-myristate-13-acetate and neutrophil elastase on mucin secretion were also investigated. Only 8-bromocyclic AMP and neutrophil elastase influenced mucin secretion. These studies provided strong evidence that the lung adenocarcinoma cell lines secrete high molecular weight mucins in culture conditions and only two of the four tested secretagogues significantly increased mucin secretion. Thus, this in vitro model system may be useful in determining alterations in mucin structure, if any, in lung adenocarcinomas as well as in studying the regulation of mucin gene expression.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1020224625088
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  • 72
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    Electronic Resource
    Quantitative analysis of transcription and translation in gene amplified Chinese hamster ovary cells on the basis of a kinetic model (1999)
    Springer
    Cytotechnology 29 (1999), S. 93-102 
    Details
    ISSN: 1573-0778
    Keywords: CHO cells ; gene expression ; kinetic model ; protein secretion ; transcription ; translation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The elevation of expression levels for secreted glycoproteins by gene amplification in mammalian cells shows a saturation behavior at high levels of gene amplification. At high expression levels a drop in the secretion efficiency for the recombinant protein occurs (Schröder and Friedl, 1997), coinciding with the appearance of misfolded protein in the cell. In this communication we investigated whether additional limitations exist at the levels of transcription and translation. Four Chinese hamster ovary (CHO) cell lines expressing different amounts of human antithrombin III (ATIII) were used as a model system. A tenfold increase in the ATIII cDNA copy number from the lowest to the highest producing cell line coincided with a 38-fold increase in ATIII mRNA levels, and an 80-fold increase in the amount of intracellular ATIII levels. The data was analyzed using a simple kinetic model. The following conclusions were derived: I. The transcriptional activity for the recombinant protein is not saturated. II. Translation itself is not saturated either, but may be downregulated as secretion efficiency drops. III. Two explanations for the previously reported drop in secretion efficiency for the recombinant protein with increasing expression level are possible: A. Protein degradation is an alternative fate for translated ATIII and the fraction of ATIII degraded after translation increases as expression level is increased. B. Translation is downregulated as the secretory apparatus becomes exhausted to maintain cell viability.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008077603328
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  • 73
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    Electronic Resource
    Embryonic stem cell differentiation models: cardiogenesis, myogenesis, neurogenesis, epithelial and vascular smooth muscle cell differentiation in vitro (1999)
    Springer
    Cytotechnology 30 (1999), S. 211-226 
    Details
    ISSN: 1573-0778
    Keywords: cardiogenesis ; cell differentiation ; gene expression ; mouse embryonic stem cells ; myogenesis ; neurogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Embryonic stem cells, totipotent cells of the early mouse embryo, were established as permanent cell lines of undifferentiated cells. ES cells provide an important cellular system in developmental biology for the manipulation of preselected genes in mice by using the gene targeting technology. Embryonic stem cells, when cultivated as embryo-like aggregates, so-called ‘embryoid bodies’, are able to differentiate in vitro into derivatives of all three primary germ layers, the endoderm, ectoderm and mesoderm. We established differentiation protocols for the in vitro development of undifferentiated embryonic stem cells into differentiated cardiomyocytes, skeletal muscle, neuronal, epithelial and vascular smooth muscle cells. During differentiation, tissue-specific genes, proteins, ion channels, receptors and action potentials were expressed in a developmentally controlled pattern. This pattern closely recapitulates the developmental pattern during embryogenesis in the living organism. In vitro, the controlled developmental pattern was found to be influenced by differentiation and growth factor molecules or by xenobiotics. Furthermore, the differentiation system has been used for genetic analyses by ‘gain of function’ and ‘loss of function’ approaches in vitro.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008041420166
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  • 74
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    Electronic Resource
    The role of the cell cycle in determining gene expression and productivity in CHO cells (1999)
    Springer
    Cytotechnology 30 (1999), S. 49-57 
    Details
    ISSN: 1573-0778
    Keywords: cell cycle ; CHO ; flow cytometry ; gene expression ; synchronisation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Understanding the relationships between cell cycle and protein expression is critical to the optimisation of media and environmental conditions for successful commercial operation of animal cell culture processes. Using flow cytometry for the analysis of the early phases of synchronised batch cultures, the dependency of product expression on cell cycle related events has been evaluated in a recombinant CHO cell line. Although the production of recombinant protein is initially found to be cell cycle related, the maximum specific protein productivity is only achieved at a later stage of the exponential phase which also sees a maximum in the intracellular protein concentration. Subsequent work suggests that it is the batch phase/medium composition of cultures which is the major determinant of maximum specific productivity in this cell line. Furthermore the effect of the positive association between S phase and specific productivity is subordinate to the effect of batch phase/medium composition on the specific productivity of batch cultures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008093404237
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  • 75
    Electronic Resource
    Electronic Resource
    Transient gene expression in mammalian cells grown in serum-free suspension culture (1999)
    Springer
    Cytotechnology 30 (1999), S. 71-83 
    Details
    ISSN: 1573-0778
    Keywords: gene expression ; HEK293(EBNA) cells ; serum-free ; transient transfection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract In order to establish a simple and scaleable transfection system we have used the cationic polymer polyethylenimine (PEI) to study transient transfection in HEK293 and 293(EBNA) cells grown in serum-free suspension culture. The transfection complexes were made directly within the cell culture by consecutively adding plasmid and PEI (direct method). Alternatively, the DNA-PEI transfection complexes were prepared in fresh medium (1/10 culture volume) and then added to the cells (indirect method). The results of this study clearly show that the ratio of PEI nitrogen to DNA phosphate is very important for high expression levels. The precise ratio is dependent on the DNA concentration. For example, using 1 μg/ml DNA by the indirect method, the ratio of optimal PEI:DNA was about 10–13:1. However, the ratio increases to 33:1 for 0.1–0.2 μg/ml DNA. By testing several different molecular weights of the polycationic polymer we could show that the highest transfection efficiency was obtained with the PEI 25 kDa. Using PEI 25 kDa the indirect method is superior to the direct addition because significantly lower DNA concentrations are needed. The expression levels of the soluble human TNF receptor p55 are even higher at low DNA compared to 1 μg/ml plasmid. The EBV-based pREP vectors gave better transient gene expression when used in 293(EBNA) cells compared to HEK293 cells in suspension culture. No differences in expression levels in the two cell lines were observed when the pC1 (CMV)-TNFR was used. In conclusion, PEI is a low-toxic transfection agent which provides high levels of transient gene expression in 293(EBNA) cells grown in serum-free suspension culture. This system allows highly reproducible, cost-effective production of milligram amounts of recombinant proteins in 2–5 l spinner culture scale within 3–5 days. Fermentor scale experiments, however, are less efficient because the PEI-mediated transient tranfection is inhibited by conditioned medium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008000327766
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  • 76
    Electronic Resource
    Electronic Resource
    Genetic Variation in Spiroplasma citri (1999)
    Springer
    European journal of plant pathology 105 (1999), S. 519-533 
    Details
    ISSN: 1573-8469
    Keywords: genome ; gene expression ; mollicute ; recombination ; transposition ; virus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Spiroplasmas are members of the Class Mollicutes, wall-less prokaryotes having a high adenosine–thymidine content in their small genomes. Spiroplasma citri is a plant pathogen that inhabits phloem. Like other phytopathogenic spiroplasmas and the related phytoplasmas, it is transmitted from plant to plant by phloem-feeding leafhoppers that serve as alternate hosts for the spiroplasma as well as vectors. Genetic information in spiroplasmas is carried on a circular chromosome, on plasmids and/or in virus genomes. A picture emerging from recent research on the S. citri genome is one of frequent and often extensive variation, resulting from a number of different mechanisms. Expansion and contraction events must continually be occurring in about equal proportions so that the net genome size varies within defined boundaries. Particularly impressive are large changes in genome size that can occur in only a few generations. As with most organisms, genetic variation in S. citri results from variation in extrachromosomal DNA content, changes due to DNA replication and repair processes and changes due to recombination. The implied flux of genetic information into and out of the S. citri genome should be beneficial to the bacterium, allowing it, with its small genome size, to adapt to new environments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008757716803
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  • 77
    Electronic Resource
    Electronic Resource
    Liver-specific and seasonal expression of transgenic Atlantic salmon harboring the winter flounder antifreeze protein gene (1999)
    Springer
    Transgenic research 8 (1999), S. 405-414 
    Details
    ISSN: 1573-9368
    Keywords: transgenic salmon ; transgene inheritance ; gene expression ; antifreeze protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We have analyzed the inheritance and expression of a line of transgenic salmon harboring the antifreeze protein gene from the winter flounder. The genomic clone 2A-7 coding for a major liver-type antifreeze protein gene (wflAFP-6) was integrated into the salmon genome. From a transgenic founder (# 1469), an F3 generation was produced. In this study, southern blot analysis showed that only one copy of the antifreeze protein transgene was integrated into a unique site in F3 transgenic fish. The integration site was cloned and characterized. Northern analysis indicated that the antifreeze protein mRNA was only expressed in the liver and showed seasonal variation. All of the F3 offspring contained similar levels of the antifreeze protein precursor protein in the sera and the sera of these offspring showed a characteristic hexagonal ice crystal pattern indicating the presence of antifreeze activity. In addition, the antifreeze protein precursor protein level was found to vary with the season, being highest in the month of November and lowest in May. This study had demonstrated a tissue-specific and stable expression of the antifreeze protein transgene in the F3 generation of the transgenic salmon 1469 line.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008900812864
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  • 78
    Electronic Resource
    Electronic Resource
    Introduction of a Proximal Stat5 Site in the Murine α-Lactalbumin Promoter Induces Prolactin Dependency In Vitro and Improves Expression Frequency In Vivo (1999)
    Springer
    Transgenic research 8 (1999), S. 23-31 
    Details
    ISSN: 1573-9368
    Keywords: transgenic mice ; prolactin ; mammary gland ; gene expression ; Stat5 ; β-globin insulator
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In order to establish a possible correlation between in vitro prolactin induction and the transcriptional activity of mammary gene promoters in transgenic mice, a functional Stat5-binding site was created by means of site-directed mutagenesis at position −70 on a 560 bp murine α-lactalbumin promotor linked to a CAT reporter gene. Surprisingly, the wild-type promoter was constitutively active in vitro and could not be induced by prolactin. Introducing the proximal Stat5 site abolished this constitutive activity and resulted in prolactin dependence in both CHO-K1- and HC11-transfected cells. In transgenic mice, both the frequency of lines expressing the transgene and the prevalence of mid to late pregnancy expression were increased.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1008851802022
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  • 79
    Electronic Resource
    Electronic Resource
    Der weite Weg der europäischen Waldbäume (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 12-17 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Die heutigen Wälder, die man in Europa vorfindet, waren nicht immer dort. VOr 22000 Jahren - im Hochglazial - gab es nur im Mittelmeergebiet die klimatischen Voraussetzungen für das Wachstum von Bäumen. Allerdings waren dies meist keine dichten Wälder, sondern Steppen mit einzelnen Baumgruppen. Das bedeutet jedoch, daß die heute in Europa wachasenden Bäume während der letzten 12000 Jahre - also seit dem Ende der letzten Eiszeit - nach Mittel- und Nordeuropa eingewandert sein müssen. Am Beispiel der Waldbäume Eiche (Quercus), Hainbuche (Carpinus), Fichtet (Picea) und Tanne (Abies) soll diese Einwanderung aufgezeigt werden.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290104
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  • 80
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    Electronic Resource
    Et in scientia ego! Von ästhetischen Momenten und Poetischen Potentialen der WissenschaftHans-Günter Gassen zum 60. Geburtstag (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 6-11 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Irgendwie wird niemand mehr richtig glücklich mit der Wissenschaft, so erfolgreich sie auch ist und so sehr unsere alltäglichen Verrichtungen von ihren Ergebnissen und Lieferungen auch abhängen. Das Verständnis der öffentlichen Beobachter nimmt trotz aller Bemühungen nicht zu, sondern ab, und die professionellen Betreiber sehen sich unentwegt nach ihrer Verantwortung gefragt und in ethische Debatten verstrickt. Die ursprüngliche Idee, daß Wissenschaft nur gut sein kann, hat massiv an Überzseugungskraft verloren, und dieser Verlust tritt deshalb besonders deutlich hervor, weil man spürt, wie die alte Basis der Rationalität brüchig geworden ist, ohne einen neuen Grund zu erkennen, auf den man in Zukunft bauen kann. Dabei übersehen wir ein Fundament, auf dem Menschen immer schon gestanden haben und zu dem sie also auch zu jeder Zeit wieder zurückkommen können.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290103
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    Aus der Redaktion (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 55-55 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290109
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  • 82
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    Blaue Liste Institute (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 56-57 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290110
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  • 83
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    Wissenschaft (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 60-60 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290113
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  • 84
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    Masthead (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999) 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290201
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  • 85
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    Gelatinöses Zooplankton - materialsparende Leichtbauweise im Ozean (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 90-97 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Die fossile Überlieferung aus den letzten präkambrischen Jahrmillionen deutet darauf hin, daß gelatinös organisierte Formenj, also quallenähnlich gebaute Organismen, die das marine Pelagial (den freien Wasserkörper des Meeres) besiedelten ‘3’. Was sie dort vorfanden war jedoch wenig labensfreundlich. Zwar wimmelte das Meer von bakterien und Protozoen, aber im wesentlichen waren die riesigen Wasserräume leer und unbesiedelt. Crustaceen und andere Organisationsformen waren - wenn die Befunde stimmen - noch in der Entwicklungsphase beziehungsweise noch nicht zu der pelagischen Lebensweise übergegangen. Wie überlebten die quallenförmigen Organismen in dieser Umwelt, und warum leben sie noch heute in allen Bereichen des Meeres, von der Flach- bis in die Tiefsee, von den Polen bis zu den Tropen? Der pelagische Lebensraum beinhaltet Tausende von Arten, die viel “höher” organisierten Gruppen angehören, die schneller und kräftiger sind. Wieso wurden die gelatinösen Plankter nicht in irgendeine skurrile Nische gedrängt oder über die Konkurrenz völlig ausgeschaltet? Mögliche Antworten auf diese Fragen finden wir in der Gegenwart.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290205
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  • 86
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    Rätsel (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 117-117 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290208
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  • 87
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    Kontrazeption beim Mann (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 110-116 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Als Fertilitätsrate bezeichnet man die Zahl der Geburten pro Frau in ihrer Lebensspanne. Wenn Zu- Oder Abwanderung in einer Population gering sind, läßt eine Fertilitätsrate von 2,0 eine konstante Bevölkerungszahl erwarten. Bei der Entwicklung der Erdbevölkerung beobachtet man in den industrialisierten Ländern derzeit keinen Anstieg. Die Fertilitätsrate liegt in den USA bei 2,1 und in Europa durchschnittlich bei 1,4. Mit 1,2 und 1,15 haben Italien und Spanien dabei die weltweit niedrigsten Fertilitätsraten. Somit ist örtlich sogar ein Bevölkerungsrücksgang zu erwarten. Auch in ostasiatischen Ländern wie China und Korea hat sich der Bevölkerungszuwachs verlangsamt. In Südasien und in afrikanischen Ländern wie China und Korea hat sich der Bevölkerungszuwachs verlangsamt. In Südlich der Sahara finden wir jedoch nach wie vor relativ hohe Gebeurtenraten. Im westafrikanischen Nigeria liegt die Fertilitätsrate bei 6,3. Für Indien und Pakistan werden Werte von 3,5 und 5,6 angegeben. Es gibt also noch viele Regionen mit einer hohen Fertilitätsrate. Manche Wissenschaftler gehen sogar davon aus, daß sich die Zahl entsprechender Staaten eher noch erhöhen wird ‘7’. Deshalb weichen auch die Schätzungen voneinander ab, bei welcher Bevölkerungszahl Wachstumsstillstand eintreten wird. Viele Demographen gehen davon aus, daß sich die Erdbevölkerung bis zum Jahr 2050 bei 10 Milliarden stabilisieren wird ‘9’. Andere schätzen, daß danach ein weiterer Ansteig auf etwa 12 Milliarden menschen zu erwarten ist ‘7’. Der Rückgang der Geburtenzahlen in den industrialisierten Ländern wurde mit kontrazeptiven Maßnahmen erzielt, die uns schon lange zur Verfügung stehen und die gut eingeführt sind. Auf den ersten Blick Sch eint es somit aus bevölkerungspolitischer Sicht auf dem Gebiet der Kontrazeption keinen zwingenden Bedarf für Neuentwicklungen zu geben. Dennoch sind Forschungsaktivitäten im Gang, die auf eine pharmakologische Kontrazeption beim Mann gerichtet sind. Im vorliegenden Artikel werden neben den traditionellen Möglichkeiten, die dem Mann zur Kontrazeption offenstehen, der wissenschaftliche Hintergrund und der Entwicklungsstand einer “Pille für den Mann” vorgestellt.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290207
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  • 88
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    Chemie (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. X 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290215
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  • 89
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    Anwendung der „Grünen Gentechnik“ ohne ökologische Risiken? (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 151-157 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Generell ist der Markt für gentechnisch veränderte Pflanzen und daraus hergestellte Produkte in den letzten Jahren gewachsen. In Deutschland zeigen sich indessen eher verhaltene Auswirkungen dieser Entwicklung ‘3’. Die wirtschaftliche Entfaltung der Gentechnik und Biotechnologie ist in Deutschland noch gering. Als ein Maß für den Entwicklungsstand der Gentechnik in der Pflanzenzüchtung ‘2’ und damit unter anderem auch deren Auswirkung auf die Futter- und Lebensmittelproduktion kann die Anzahl von Freisetzungsvorhaben mit gentechnisch veränderten Organismen (GVO) gelten. Von den rund 1300 Freisetzungsvorhaben im Bereich der EU entfallen 90 auf Deutschland. Im Vergleich zu den anderen EU-Mitgliedsstaaten rangiert Deutschland damit auf dem siebenten Platz.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290305
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  • 90
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    Rätsel (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 188-188 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290310
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  • 91
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    Landwirtschaftlicher Pflanzenbau und biologische Vielfalt (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 177-183 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Vielfalt in allen Erscheinungsformen kennzeichnet schon die unbelebte und in noch stärkerem Maße die belebte Natur. Dagegen drängt die Nutzung von Naturkräften durch den Menschen, insbesondere in ihren weiter entwickelten und technisierten Formen stets auf Vereinfachung. So werden landwirtschaftliche Kulturpflanzen bei ein- bis mehrjähriger Nutzung im Regelfall in Reinkultur angebaut, ganz im Gegensatz zur standorttypischen Artenvielfalt eines natürlichen Pflanzenbestandes. Lediglich die verbliebene Unkrautflora erinnert dann and die ursprüngliche Artenvielfalt einer Pflanzengesellschaft. Es kommt hinzu, daß sich landwirtschaftlicher Pflanzenbau auf nur wenige anbauwürdige Kulturpflanzenarten konzentriert. Weltweit nimmt das Ackerland etwa 10 % der Landoberfläche der Erde ein, die mit nur etwa 30 Kulturpflanzenarten von überregionaler Bedeutung bestellt werden. Allein 37,4% davon sind dem Anbau von nur dreif für die Ernährung der Menschheit besonders bedeutsamen Arten (Weizen, Resi und Mais) gewidmet. In Deutschland werden gegenwärtig sogar 33% der Landoberfläche als Ackerland genutzt. Von den insgesamt etwa 14 bei uns häufiger anzutreffenden Kulturpflanzenarten besetzen die drei dominierenden Arten (Winterweizen, Mais und Wintergerste) dabei 48% der Anbaufläche. Landwirtschaftlicher Pflanzenbau wird also generell artenarm betrieben.Die zweite Ebene bilogischer Vielfalt im landwirtschaftlichen Pflanzenbau stützt sich auf die mehr oder weniger regelmäßige Folge verschiedener in Reinkultur angebauter Kulturpflanzenarten. Bozogen auf die Gesamtfläche eines Betriebes order die Feldflur einer Gemeinde ergibt sich dann noch immer ein abwechslungsreiches Gesamtbild verschiedener Aussaat-, Blühund Erntezeiten. Für artenreiche Fruchtfolgen lassen sich darüber hinaus viele, für die Bodenbewirtschaftung vorteilhafte Argumente anführen. Die hohe Schlagkraft der vollmechanisierten Betriebe und die beliebige Verfügbarkeit von Dünge- und Pflanzenschutzmitteln in Verbindung mit artunterschiedlichen Ertrags- und Preisrelationen haben jedoch auf intensive bewirtschafteten Betrieben in günstigen Lagen zu einer oft drastischen Reduktion der Pflanzenproduktion (auf den Anbau von nur noch drei, manchmal sogar nur zwei Arten) geführt, von denen der jeweils höchste Beitrag zur Deckung der Betriebskosten erwartet werden kann.Inzwischen hat sich jedoch die Erkenntnis durchgesetzt, daß die Aufrechterhaltung “biologischer Diversität” ein wesentliches Element zur Sicherung der “Nachhaltigkeit” der landwirtschaftlichen Pflanzenproduktion darstellt. Dies hat in der Konferenz von Rio (1992) im Rahmen der Agenda 21 zum Abschluß einer “Konvention über Biologische Vielfatl” geführt, der auch die Bundesrepublik Deutschland beigetreten ist.Mit dem Begriff biologische Vielfalt werden in dieser Konvention nicht nur Naturschutzverpflichtungen zur Sicherung des Erhalts bedrohter Tier- und Pflanzenarten übernommen, sondern es geht zu einem wesentlichen Teil auch um die 3. Ebene der biologischen Vielfalt in Form der genetischen Vielfalt innerhalb der für die Welternährung grundlegend bedeutsamen Kulturpflanzenarten. In diesem Zusammenhang soll hier gefragt werden, ob mit der Einführung transgener Nutzpflanzen neben ihrem wirtschaftlichem Nutzen auch Risiken für die biologische Vielfatl verbuden sind.
    Additional Material: 2 Ill.
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    URL: http://dx.doi.org/10.1002/biuz.960290308
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  • 92
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    Masthead (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999) 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290401
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  • 93
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    Jagd- und Paralysierungsstrategien solitärer Wespen (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 223-237 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Zu den faszinierendsten “Waffen” im Tierreich gehören die Gifte. Auch viele Insekten setzen Gifte ein, zum Beispiel als Wehrgifte, wie sie von den staatenbildenden sozialen Hymenopteren, den Bienen, Hornissen und Faltenwespen bekannt sind. Die Wirkung dieser Gifte ist aufgrund ihrer medizinischen Bedeutung bereits intensiv untersucht. Über die Art und Weise der Giftinjektion sowie die Wirkungsweise der Gifte solitär lebender Wespenarten, etwa von Weg- und Grabwespen, ist vergleichs weise wenig bekannt. Eine Besonderheit der solitären Wespenarten ist, daß ausschließlich ihre Weibchen Insekten oder Spinnen jagen, um ihre künftige Brut zu versorgen. Spezielle jagdstrategien verringern dabei die Gefahr, daß potentielle Beutetiere die jagenden Wespenweibchen früch zeitig entdecken. Ist ein Beutetier optisch und/oder chemisch identifiziert. wird es je nach Wespenart durch einen oder mehrere Stiche paralysiert (gelähmt). Anfängliches Abwehrverhalten, selbst größerer Beutetiere, wird auf diese Weise unterbunden, und die Opfer können an einen sicheren Ort, ein Nest oder eine umfangreiche Nestanlage mit günstigem Mikroklima, gebracht werden, wo anschließend ein Ei abgelegt wird. Die sich auf ihrem Wirt entwickelnde Larve ist so vor dem Zugriff durch Feinde geschützt.Die an der Beute als Folge eines Stiches zu beobachtenden Giftwirkungen reichen von der vollständigen Paralyse, also dem totalen, in einigen Fällen auch irreversiblen Verlust der Fähigkeit, such zu bewegen, über vielfähigkeit, sich zu bewegen, über vielfältige, durch sas Gift bewirkte auffällige Verhaltensänderungen. Im Hinblick auf das Nervensystem lassen sich peri pher und zentral wirkende Gifte unter sscheiden, wobei der Wirkort durch das Stechverhalten der Wespe vorgegeben sein kann.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290406
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    Blaue Liste Institute (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 256-256 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: No Asbstract.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290411
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    Für Ihre Dokumentation von Nr. 4/99 Biologie in unserer Zeit (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 260-260 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290414
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  • 96
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    Verschwendung oder Sparsamkeit? - Über den Umgang der Blütenpflanzen mit ihrem Pollen (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 268-277 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Additional Material: 18 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290503
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    Induzierbare VerteidigungsmechanismenHerrn Prof. Dr. Klaus Heckmann zum 65. Geburtstag gewidmet. (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 292-300 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Zu en vielen Schutz- und Verteidigungsstrategien, die von den Organismen entwickelt wurden, um dem Gefressenwerden zu entgehen, Zählen ein sperrigerwerden der Individuen, die Bildung von Panzern, Stacheln und Dornen, das Produzieren und Speichern von schwerverdaulichen Stoffen und Giften, aber auch die Entwicklung eines komplexen verhaltensrepertoires zur Vermeidung von Freßfeinden ‘8’. Bis zur dieses Jahrhunders glaubte man, daß die der Verteidigung dienenden Maßnahmen dauerhaft seien, also im Laufe der Evolution entstanden sind und im Verlauf ddes Lebens eines Individuums zu einem bestimmten Zeitpunkt zur Ausprägung, gelangen, unabhängig von der gerad herrschenden Bedrohung. Heute wissen wir, daß neben einer solchen kionstitutiven Verteidigung in vielen Organismengruppen auch induzierbare Verteidigungsmechanismen existieren, welche nur dann wirksam werden wenn Freßfeinde im Biotop in größerer Dchte auftreten und somit eine ernstzunehmende Bedrohung darstellen. Das Spektrum induzierbarer Feindabwehrmechanismen ist der Palette der kionstitutiven Abwehrmaßnahmen dabei durchaus sehr ähnlich. Der entscheidende Unterschied ist jedoch der, daß der bedrohte Organismus erst auf ein bestimmtes Signal hin von seinem genetisch festgelegten Schutzmechanismus Gebrauch macht. Dadurch werden die Kostenfür die Feindabwehr minimiert. Neben physikalischen Signalen (wie Licht und Temperatur), welche dem Organismus indirekt Auskunft über den Grad einer aktuellen Bedrohung geben können, spielen von den Freßfeinden abgegebene chemische Signale (Kairomone) eine entscheidende Rollen als Auslöser der induzierbaren Verteidigungsmechanismen. An der Aufklärung der chemischen Natur der Kariomione wird zur Zeit intenxiv gearbeitet.
    Additional Material: 8 Ill.
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    URL: http://dx.doi.org/10.1002/biuz.960290506
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    Rütsel (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 307-307 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290508
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    Interview (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. 309-309 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Seit 1989 organisieren die beiden Zoologen Prof. Dr. H. K. Schminke aus Oldenburg und Prof. Dr. W. Westheide aus Osnabrück im Sommer einwöchige Intensivkurse zur Vermittlung taxonomisch-ökologischer Kenntnisse über einheimische Tiergruppen. BIUZ wollte mehr über diese Kurse und ihre Ziele wissen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290510
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  • 100
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    Biologie (1999)
    Weinheim : Wiley-Blackwell
    Biologie in unserer Zeit 29 (1999), S. V 
    Details
    ISSN: 0045-205X
    Keywords: Life and Medical Sciences
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/biuz.960290513
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