Library

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1995-1999  (31)
  • 1990-1994  (291)
  • 1996  (31)
  • 1994  (291)
  • Genetics
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Acta diabetologica 33 (1996), S. 257-262 
    ISSN: 1432-5233
    Keywords: Key words NIDDM ; Candidate genes ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Acta diabetologica 33 (1996), S. 257-262 
    ISSN: 1432-5233
    Keywords: NIDDM ; Candidate genes ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 92 (1996), S. 382-387 
    ISSN: 1432-2242
    Keywords: Genetics ; Blacking resistance ; Brassica napus ; Brassica juncea ; Leptosphaeria maculans
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The genetic control of adult-plant blackleg (Leptosphaeria maculans) resistance in a Brassica napus line (579NO48-109-DG-1589), designated “R13” possessing Brassica juncea-like resistance (JR), was elucidated by the analysis of segregation ratios in F2 and F3 populations from a cross between “R13” and the highly blackleg-susceptible B. napus cultivar “Tower”. The F2 segregration ratios were bimodal, demonstrating that blackleg resistance in “R13” was controlled by major genes. Analysis of the segregation ratios for 13 F3 families indicated that blackleg resistance in these families was controlled by three nuclear genes, which exhibited a complex interaction. Randomly sampled plants of F3 progeny all had the normal diploid somatic chromosome number for B. napus. The similarities between the action of the three genes found in this study with those controlling blackleg resistance in B. juncea is discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 92 (1996), S. 817-826 
    ISSN: 1432-2242
    Keywords: Zea mays ; RFLPs ; Plant breeding ; Genetics ; Recombination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This study was conducted to compare maize quantitative trait loci (QTL) detection for grain yield and yield components in F2∶3 and F6∶7 recombinant inbred (RI) lines from the same population. One hundred and eighty-six F6∶7 RIs from a Mo17×H99 population were grown in a replicated field experiment and analyzed at 101 loci detected by restriction fragment length polymorphisms (RFLPs). Single-factor analysis of variance was conducted for each locus-trait combination to identify QTL. For grain yield, 6 QTL were detected accounting for 22% of the phenotypic variation. A total of 63 QTL were identified for the seven grain yield components with alleles from both parents contributing to increased trait values. Several genetic regions were associated with more than one trait, indicating possible linked and/or pleiotropic effects. In a comparison with 150 F2∶3 lines from the same population, the same genetic regions and parental effects were detected across generations despite being evaluated under diverse environmental conditions. Some of the QTL detected in the F2∶3 seem to be dissected into multiple, linked QTL in the F6∶7 generation, indicating better genetic resolution for QTL detection with RIs. Also, genetic effects at QTL are smaller in the F6∶7 generation for all traits.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1432-1920
    Keywords: Key words Myotonic dystrophy ; Magnetic resonance imaging ; Brain ; Muscles ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Amplification of an unstable CTG trinucleotide repeat sequence in a protein kinase gene on chromosome 19 has recently been recognised as the molecular basis of myotonic dystrophy (DM), a multisystem disorder with a wide spectrum of muscular and extramuscular manifestations. The CTG expansion of 40 patients was assessed by direct genotype analysis of the white blood cell DNA and correlated with MRI of the brain and muscles, and with functional clinical data. Cerebral pathology on MRI consisted of diffuse atrophy (68 %), subcortical white matter lesions (65 %), wide Virchow-Robin spaces (38 %) and thickening of the skull (35 %). Cerebral atrophy and extent of white matter disease correlated significantly with mental retardation, duration of disease and CTG fragment amplification. MRI of the muscular system showed fatty degeneration of different degrees in neighbouring muscles causing a mosaic pattern of the thigh in 38 % and the calf in 44 %. Muscular changes on MRI were strongly correlated with muscular impairment but less strongly with CTG expansion. Changes on MRI reflect the stage of development of tissue pathology in DM, modified by defect of the DM gene. Pathology on MRI is strongly correlated with functional deficits.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Oecologia 108 (1996), S. 419-423 
    ISSN: 1432-1939
    Keywords: Barnyard grass ; Seed dormancy ; Geographic variation ; Genetics ; Ecophysiology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In 1991–1993, we investigated the incidence of seed dormancy in 25 local populations of barnyard grass, Echinochloa crus-galli (L.) P.Beauv., in the western Czech Republic. The percentage of germination after 4 months afterripening of dry seeds at 25°C varied between 0.0 and 83.6%. Although there were significant annual differences in the percentage of germination at some localities, typical proportions of dormant seeds persisted over 3 years at field sites where the seed bank was not disturbed. One-way ANOVA (using data from 14 cultivated or abandoned fields) revealed that 73.0% of variance in seed dormancy incidence could be attributed to the effect of locality (P〈0.001). Incidence of dormancy was not correlated with mother plant stature (dry above-ground biomass, number of tillers, maximal stem height) nor seed mass. There was a significant correlation (r 2=0.403, P〈0.005) between dormancy incidence at natural localities in 1991 and in F1 offspring sown at experimental grounds at Praha-Ruzyně in 1992. The results indicate that heredity is important in maintaining local variation in seed dormancy, probably favoured by the self-pollinating reproduction of barnyard grass.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 74 (1996), S. 515-521 
    ISSN: 1432-1440
    Keywords: Key words Emotionality ; Behaviour ; Genetics ; Animal models ; QTL analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  It seems that the genetic basis of common psychiatric diseases such as schizophrenia and manic-depressive psychosis is amenable to the genetic mapping strategies that have been successful in other complex disorders such as diabetes. The next challenge is the genetic dissection of quantitative behavioural traits such as mood, personality and intelligence. Quantitative traits pose new problems for gene cloning experiments. We argue that one way forward is by using animal models. One of the features of quantitative traits is that the DNA sequence variants which are responsible for them are unlikely to be immediately recognizable. In contrast to many qualitative traits where a discrete phenotypic difference is often the consequence of an inactivating mutation, the allelic variation responsible for quantitative traits probably has a more subtle basis. This distinction means that strategies to clone the genetic basis of quantitative behavioural traits will have to rely on functional assays of alleles thought to be important in determining the phenotype. We suggest that an efficient strategy for detecting sequences that give rise to quantitative behavioural traits can be devised in the mouse. The importance and utility of the mouse for quantitative trait analysis make it worthwhile to investigate mouse models of human behaviour; these advantages outweigh the difficulties that arise in attempts to validate the animal models. As an example we review the evidence that validates rodent emotionality as an animal model for susceptibility to human anxiety. We show that there is good evidence that rodent emotionality is a central nervous system state with a genetic basis, and that there are neuropharmacological and neuroanatomical parallels with human anxiety. Furthermore, our own work has shown that the genetic basis of the trait is relatively simple, and that the task of characterizing it at a molecular level is feasible. We expect that future experiments will show us how genetic variation gives rise to quantitative behavioural traits.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 74 (1996), S. 515-521 
    ISSN: 1432-1440
    Keywords: Emotionality ; Behaviour ; Genetics ; Animal models ; QTL analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract It seems that the genetic basis of common psychiatric diseases such as schizophrenia and manic-depressive psychosis is amenable to the genetic mapping strategies that have been successful in other complex disorders such as diabetes. The next challenge is the genetic dissection of quantitative behavioural traits such as mood, personality and intelligence. Quantitative traits pose new problems for gene cloning experiments. We argue that one way forward is by using animal models. One of the features of quantitative traits is that the DNA sequence variants which are responsible for them are unlikely to be immediately recognizable. In contrast to many qualitative traits where a discrete phenotypic difference is often the consequence of an inactivating mutation, the allelic variation responsible for quantitative traits probably has a more subtle basis. This distinction means that strategies to clone the genetic basis of quantitative behavioural traits will have to rely on functional assays of alleles thought to be important in determining the phenotype. We suggest that an efficient strategy for detecting sequences that give rise to quantitative behavioural traits can be devised in the mouse. The importance and utility of the mouse for quantitative trait analysis make it worthwhile to investigate mouse models of human behaviour; these advantages outweigh the difficulties that arise in attempts to validate the animal models. As an example we review the evidence that validates rodent emotionality as an animal model for susceptibility to human anxiety. We show that there is good evidence that rodent emotionality is a central nervous system state with a genetic basis, and that there are neuropharmacological and neuroanatomical parallels with human anxiety. Furthermore, our own work has shown that the genetic basis of the trait is relatively simple, and that the task of characterizing it at a molecular level is feasible. We expect that future experiments will show us how genetic variation gives rise to quantitative behavioural traits.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Der Nervenarzt 67 (1996), S. 837-845 
    ISSN: 1433-0407
    Keywords: Schlüsselwörter Migräne ; Genetik ; Familiäre Hemiplegische Migräne ; Linkageanalyse ; Zwillingsstudien ; Assoziationsstudien ; Key words Migraine ; Familial Hemiplegic Migraine ; Genetics ; Linkage analysis ; Twin studies ; Association studies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Several historical reports focusing on the heredity of migraine, as well as recent studies on its epidemiology and molecular biology, have revealed evidence for a decisive role of genetic factors in the aetiopathogenesis of familial migraine. Indeed, family studies, segregation analyses and twin studies have shown that genetic factors play an important role in disposition towards migraine but could not explain the entire aetiopathogenesis. The influence of extragenetic factors, however, remains mostly unknown. Recent linkage analyses have provided evidence for genetic heterogeneity. A locus for Familial Hemiplegic Migraine (FHM), the only known type of migraine that follows autosomal-dominant transmission, has been linked to chromosome 19p13 but genetic heterogeneity has also been shown, i. e. different types of migraine could be excluded from this locus. Further investigations should concentrate on identifying the FHM gene on chromosome 19p13, on linkage analyses with markers for different susceptibility genes, and on genomic analyses of highly informative pedigrees. This would lead to further clues to the pathogenesis underlying migraine and, thus, to therapeutic developments.
    Notes: Zusammenfassung Nachdem bereits in historischen Beschreibungen eine genetische Verursachung der Migräne vermutet worden war, haben epidemiologische und molekularbiologische Forschungen in den letzten Jahren differenzierte Ergebnisse über genetische Faktoren in der Ätiopathogenese der familiären Migräne geliefert. Aufgrund von Familien- und Segregationsanalysen und von Zwillingsstudien wird dargestellt, daß genetische Faktoren mit größter Wahrscheinlichkeit eine Rolle in der Pathogenese der typischen Migräne spielen. Inwieweit extragenetische Faktoren auf die Ätiopathogenese der Migräne Einfluß nehmen, ist weitgehend offen. Linkageanalysen haben in jüngster Zeit gezeigt, daß möglicherweise mehrere verschiedene Gene für diese Erkrankung verantwortlich sind. Für die Familiäre Hemiplegische Migräne (FHM), der einzigen Migräneform, für die ein autosomal-dominanter Erbgang nachgewiesen ist, konnte ein Genlocus auf Chromosom 19p13 gefunden werden, gleichzeitig wurde aber auch genetische Heterogenität nachgewiesen. Verschiedene andere Formen der Migräne zeigten keine Linkage zu diesem Locus. Weitere Forschungen sollten neben der Identifizierung des FHM-Gens auch Linkageanalysen für Kandidatengene und Genomanalysen an großen informativen Familien zum Ziel haben. Letztlich werden die Ergebnisse genaueren Einblick in die Pathophysiologie der Migräne liefern und damit therapeutisch relevant sein.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1433-2965
    Keywords: Bone density ; Femor geometry ; Genetics ; Twins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To estimate genetic effects on femoral neck geometry and the distribution of bone mineral within the proximal femur a cross-sectional twin analysis was carried out at a university hospital that compared correlations in these traits in pairs of mono- and dizygo-tic female twins. Monozygotic (MZ, n=51 pairs, age 49.1±9.3 years) and dizygotic (DZ, n=26 pairs, age 45.7±11.3 years) twins were randomly selected from a larger sample of twins previously studied. Measurements of bone mineral density (BMD), femoral neck angles and length, cross-sectional area and moment of interia, the center of mass of the narrowest cross-section of the femoral neck, and BMDs of regions within the femoral neck were made. A summary index of the resistance of the femoral neck to forces experienced in a fall with impact on the greater trochanter (Fall Index, FI) was calculated. MZ pair intraclass correlations (rMZ) were significantly (p〈0.05) different from zero for all bone mass and femoral geometry variables (0.35〈rMZ〈0.82). DZ pair correlations (rDZ) were lower thanrMZ for all variables (0.04〈rDZ〈0.52) except femoral neck length (rDZ=0.38, rMZ=0.36). After adjustment for BMD of the femoral neck,rMZ was significantly greater thanrDZ, yielding high heritability estimates for regional BMDs (0.72〈H 2〈0.78), the center of mass of the femoral neck (H 2=0.70, −0.04 to 1.43 95% CI) and the resistance of the femoral neck to forces experienced in a fall (FI,H 2=0.94, 0.06 to 1.85 95% CI), but not for femoral neck length. Adjustments for age did not alter these findings. It is concluded that there are significant familial influences on the distribution of femoral bone mass and on the calculated structural strength of the proximal femur, but not on femoral neck length. If the assumptions of the twin model are correct, this is evidence for genetic factors influencing these traits.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 11
    ISSN: 1432-0533
    Keywords: Key words Alzheimer’s disease ; Clinicopathological ; correlations ; Early-onset dementia ; Genetics ; Pick’s ; disease
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Diabetologia 39 (1996), S. 375-382 
    ISSN: 1432-0428
    Keywords: Genetics ; maternally inherited diabetes and deafness ; NIDDM ; IDDM ; mitochondria ; MELAS syndrome
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Diabetes mellitus is a common disease with many forms of clinical expression. In addition, the development of diabetic complications is not only dependent on glycaemic control but also on individual factors which may be related to genetic heterogeneity. At present, multiple genetic factors are being recognized as contributing to the development of diabetes or possibly modulating its clinical expression. The purpose of this review is to give an overview of our current knowledge on a subtype of diabetes which is apparently caused by a single mutation in the mitochondrial DNA.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 13
    Electronic Resource
    Electronic Resource
    Springer
    European journal of pediatrics 155 (1996), S. 540-544 
    ISSN: 1432-1076
    Keywords: Key words Amyloidosis ; Arab ; children ; Familial Mediterranean ; fever ; Genetics ; Recurrent ; abdominal pain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Over a period of 3 years, 192 children with familial Mediterranean fever were prospectively studied. Of these, 106 (55%) were girls and 86 (45%) were boys. The prevalence was 1 : 2600 children with a gene frequency of 1 : 50. The age at onset ranged between 4 months and 16 years. Of these patients 24% started their illness below the age of 2 years and 88% were symptomatic before the age of 10 years; 82% had recurrent abdominal pain, 43% had pleurisy, 37% had arthritis, 15% had cutaneous manifestations, 12% had splenomegaly and 4% had hepatomegaly. The presenting symptoms were abdominal pain in 51%, unilateral chest pain in 23% and arthritis in 26%. The family history was positive in 62%. Of 12 affected families 19 members had/have renal failure and amyloidosis was confirmed in 7 patients. Conclusion Our data show a high prevalence of familial Mediterranean fever and a high gene frequency in Arab children similar to that reported in Jews and Armenians.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 14
    Electronic Resource
    Electronic Resource
    Springer
    European journal of pediatrics 155 (1996), S. 540-544 
    ISSN: 1432-1076
    Keywords: Amyloidosis ; Arab children ; Familial Mediterranean fever ; Genetics ; Recurrent abdominal pain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Over a period of 3 years, 192 children with familial Mediterranean fever were prospectively studied. Of these, 106 (55%) were girls and 86 (45%) were boys. The prevalence was 1∶2600 children with a gene frequency of 1∶50. The age at onset ranged between 4 months and 16 years. Of these patients 24% started their illness below the age of 2 years and 88% were symptomatic before the age of 10 years: 82% had recurrent abdominal pain, 43% had pleurisy, 37% had arthritis, 15% had cutaneous manifestations, 12% had splenomegaly and 4% had hepatomegaly. The presenting symptoms were abdominal pain in 51%, unilateral chest pain in 23% and arthritis in 26%. The family history was positive in 62%. Of 12 affected families 19 members had/have renal failure and amyloidosis was confirmed in 7 patients.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 15
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 92 (1996), S. 817-826 
    ISSN: 1432-2242
    Keywords: Key words  Zea mays ; RFLPs ; Plant breeding ; Genetics ; Recombination ; Abbreviations  RFLPs Restriction fragment length polymorphisms ; QTL quantitative trait loci ; RIs recombinant inbreds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract   This study was conducted to compare maize quantitative trait loci (QTL) detection for grain yield and yield components in F2:3 and F6:7 recombinant inbred (RI) lines from the same population. One hundred and eighty-six F6:7 RIs from a Mo17×H99 population were grown in a replicated field experiment and analyzed at 101 loci detected by restriction fragment length polymorphisms (RFLPs). Single-factor analysis of variance was conducted for each locus-trait combination to identify QTL. For grain yield, 6 QTL were detected accounting for 22% of the phenotypic variation. A total of 63 QTL were identified for the seven grain yield components with alleles from both parents contributing to increased trait values. Several genetic regions were associated with more than one trait, indicating possible linked and/or pleiotropic effects. In a comparison with 150 F2:3 lines from the same population, the same genetic regions and parental effects were detected across generations despite being evaluated under diverse environmental conditions. Some of the QTL detected in the F2:3 seem to be dissected into multiple, linked QTL in the F6:7 generation, indicating better genetic resolution for QTL detection with RIs. Also, genetic effects at QTL are smaller in the F6:7 generation for all traits.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Psychopharmacology 124 (1996), S. 332-339 
    ISSN: 1432-2072
    Keywords: Nicotine ; Genetics ; Self-administration ; Reinforcement ; Seizures
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Inbred mouse strains differ in sensitivity to a first dose of nicotine and in the development of tolerance to nicotine. The experiments reported here used six inbred mouse strains (A, BUB, C3H, C57BL/6, DBA/2, ST/b) that differ in sensitivity to an acute challenge dose of nicotine to determine whether differences in oral self-selection of nicotine exist. Animals were presented with solutions containing nicotine or vehicle (water or 0.2% saccharin) and their daily intake of the two fluids was measured for 4 days starting with a 10 µg/ml nicotine solution. This was followed by sequential 4-day testing with 20, 35, 50, 65, 80, 100, 125, 160, and 200 µg/ml nicotine solutions. The strains differed dramatically in their self-selection of nicotine and in maximal daily dose (mg/kg); the rank order of the strains was C57BL/6〉DBA〉BUB〉A≥C3H≥ST/b for both the tap water and 0.2% saccharin choice experiments. Correlations between nicotine consumption and sensitivity to nicotine, as measured by a battery of behavioral and physiological responses, were also calculated. Strain differences in nicotine intake were highly correlated with senstivity to nicotine-induced seizures. As senstivity to nicotine-in-duced seizures increases, oral self-selection of nicotine decreases. This finding may suggest that this toxic action of nicotine serves to limit intake.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 17
    ISSN: 1530-0358
    Keywords: Colorectal neoplasms ; Genetics ; K-ras ; Gene mutations ; Early diagnosis ; Polymerase chain reaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Purpose: Best chances of a cure from colorectal cancer are obtained before metastatic spread. Lack of specific tests allowing early diagnosis of the tumor accounts for investigation of gene alterations involved in carcinogenesis by a noninvasive method. In the present study, K-ras codons 12 and 13 mutations were studied in neoplastic cells shed from the bowel into the stool and those contained in the tumor and normal mucosa. Moreover, healthy patients and a few others with precancerous conditions were examined. METHODS: Stool, tumor, and mucosa samples were taken from 25 patients with colorectal adenocarcinoma. Stool and mucosa samples were obtained from 11 healthy patients, and stool, pathologic bowel tissue, and normal mucosa samples were obtained from 3 patients with adenoma (1) or ulcerative colitis (2). Polymerase chain reaction amplification and restriction enzyme analysis were performed. RESULTS: K-ras codon 12 mutations were detected in both tumor and stool samples of 10 cancer patients, and no gene alterations were observed in 14 patients. In one patient with a tumor, a mutation was shown in only the tumor tissue. The agreement rate in tumor and stool analysis was 96 percent. A normal pattern of K-ras codons 12 and 13 was observed in the bowel mucosa. All stool and mucosa samples from healthy patients were not altered in K-ras.Agreement was registered between samples taken from patients with preneoplastic lesions. CONCLUSIONS: These preliminary findings show a high rate of accuracy in the investigation of K-ras alterations in the colorectal cells shed into the feces, suggesting that such an approach could be used to study other gene alterations and, prospectively, to identify early colorectal cancers.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 18
    ISSN: 1437-160X
    Keywords: SLE ; Apoptosis ; bcl-2 gene ; Susceptibility ; Linkage ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Systemic lupus erythematosus (SLE) is an autoimmune disease characterised by the production of a large number of autoantibodies. It has been postulated that this may be the result of prolonged longevity of auto-reactive B cells due to defective regulation of programmed cell death (apoptosis). The proto-oncogenebcl-2 is involved in the control of apoptosis in immunocompetent cells, and its over-expression is noted in T and B cells from SLE patients. This study examined the genetic linkage between thebcl-2 gene locus and SLE susceptibility using the affected sib-pair method in SLE families. Seventeen caucasian multiplex families were evaluated. A polymorphic microsatellite marker closely linked to thebcl-2 gene on 18g21.3 was used to determine thebcl-2 genotype. We demonstrated that haplotype sharing among the affected sibling pairs was not statistically different from random (P〉0.5). This suggests that thebcl-2 gene locus does not confer a genetic susceptibility to SLE expression.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 19
    ISSN: 1573-0905
    Keywords: Compensation ; Dyslexia ; Environment ; Familial aggregation ; Genetics ; Risk
    Source: Springer Online Journal Archives 1860-2000
    Topics: Education
    Notes: Abstract When one or both parents have a history of developmental reading disorder (RD) in childhood, the risk to their offspring for developing reading problems is substantially increased. However, risk research has usually assumed a stability of reading problems across the lifespan (i.e., if a parent was affected in childhood, he or she remains affected in adulthood). Yet, some individuals with RD in childhood compensate for the disorder as they grow older. Both an environmental and genetic hypothesis would predict that the risk for RD in offspring will vary as a function of parental compensation. This study examined whether risk to offspring was dependent on the parents' successful or unsuccessful compensation for their childhood reading problems. Two large family data sets were analyzed (N=907). Diagnoses with either an age discrepant or IQ discrepant criteria essentially showed that having at least one still affected parent (i.e., RD both as a child and as an adult) put the offspring at a higher risk for RD than having at least one compensated parent (i.e., RD as a child but not as an adult). The lowest risk to an offspring occurred when both parents were never affected (i.e., not RD as a child or as an adult). The implications of these findings are discussed with regard to counseling and early diagnosis of reading problems.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 20
    Electronic Resource
    Electronic Resource
    Springer
    European archives of psychiatry and clinical neuroscience 246 (1996), S. 175-181 
    ISSN: 1433-8491
    Keywords: Schizophrenia ; Genetics ; Liability ; Vulnerability ; Eye-tracking dysfunction ; Eye movements ; Smooth-pursuit eye movements
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract There is increasing evidence that the genetic predisposition for schizophrenia in families affects more individuals than those fulfilling the criteria for schizophrenia. This finding is supposed to be one of the major problems in molecular genetic schizophrenia research, especially when linkage studies are employed. Eye-tracking dysfunction (ETD), which is conceived as a possible phenotypic marker for genetic liability to schizophrenia, may offer considerable advantages. However, there is only little information from families with multiple occurrence of schizophrenia. It is still unclear whether in these families ETD aggregates with diagnoses from the schizophrenia spectrum. This first report from an ongoing study presents the results of 48 individuals from 6 multiplex families. Smooth-pursuit eye movements were recorded by infrared reflectometry and assessed by quantitative measurement techniques. Along with the high degree of psychiatric morbidity in these families, in 56.3% of the individuals ETD was assessed. Reduced mean pursuit gain was present in 39.6%. The distribution of eye-tracking dysfunction resembles the distribution of schizophrenia-related psychiatry morbidity.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 21
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 92 (1996), S. 267-272 
    ISSN: 1432-2242
    Keywords: Cerrado ; Savannah ; Acid soils ; Hydroponics ; Nutrient ; Variety ; Genetics ; Inheritance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The soybean is a major crop in the agricultural systems of the Brazilian Cerrados (Savannahs), whose soils are acidic, devoid of nutrients and need to be amended before they are cultivated. However, below the ploughed layer there is a scarcity of nutrients and toxic aluminium (Al). These limit root growth, subsequently causing nutritional imbalance and drought stress. Our aim in the investigation described here was to identify genetic differences in the aluminium tolerance of soybeans by a 9 × 9 diallel cross among contrasting varieties grown in high-Al areas and in hydroponics. Combining ability analysis indicated predominantly additive gene effects, and the additive-dominance model explained most of the genetic differences in this germ plasm for mineral element absorption and root growth under aluminium stress. The relationship between the two factors suggest that conjugation hydroponics and field evaluations in breeding programmes would further improve soybeans with respect to yield stability under tropical cultivation conditions.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 22
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 93 (1996), S. 301-306 
    ISSN: 1432-2242
    Keywords: Leptosphaeria maculans ; Brassica napus ; Blackleg ; Genetics ; Virulence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The genetic basis of virulence of 24 isolates of L. maculans collected from various sites throughout south-eastern and south-western Australia were studied using five clone-lines of B. napus. The experimental design allowed the estimation of the environmental and genetic components of variance using a standard analysis of variance. Virulence of these isolates (as measured by the percentage of stem girdling, %G) on the clonelines NCII and Tap was found to be most likely controlled by a small number of genes; the broad-sense heritabilities were 79.7% and 67.5% for virulence on NCII and Tap, respectively. The significance of these results in relation to the potential of L. maculans in adapting to new resistant B. napus cultivars is discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 23
    ISSN: 1432-2242
    Keywords: Extreme virus resistance ; Potyviruses ; Genetics ; Genes Ry and Ra ; New gene
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Extreme resistance in cultivated potato (Solanum tuberosum) to potato viruses Y and A (PVY and PVA) conditioned by the presence of Ry genes introduced from Solanum stoloniferum was described by Cockerham (1970). Cockerham detailed a number of genes which controlled a variety of reactions, including extreme resistance to both viruses (i.e. little or no visible reaction of plants and no viral replication following graft and manual inoculation) controlled by gene Ry sto. In the present study, cvs ‘Pirola’ and ‘Barbara’, which contain a Ry gene, were found to have extreme resistance to PVY isolates from the ordinary (PVY°), veinal necrosis (PVYN) and potato tuber necrotic ringspot (PVYNTN) subgroups, and PVA. The inheritance of this phenotype was examined in seedling progenies obtained by crossing ‘Barbara’ and ‘Pirola’ with susceptible cultivars. Segregation data for resistance to PVY and PVA in a progeny involving cv ‘Pirola’ best fitted a genetical model of one gene controlling extreme resistance to both PVY and PVA, although the possibility that there are two genes, each controlling resistance to one virus but closely linked, cannot be excluded. Segregation data from progenies involving cv ‘Barbara’ best fitted a genetical model in which there are two independent genes, one controlling extreme resistance to PVA and PVY and a second gene controlling extreme resistance to PVA but not to PVY. This previously unrecognised gene conferring extreme resistance to PVA only, should be given the notation Ra in keeping with nomenclature used for other resistance genes.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 24
    ISSN: 1432-2242
    Keywords: Aluminum toxicity ; Diallel analysis ; Genetics ; Rice ; Variability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A study was undertaken to investigate the variability among lowland rice cultivars and the mode of gene action of aluminum (Al) toxicity tolerance in rice. Pregerminated seeds were grown in a nutrient solution containing 30 ppm Al and in normal nutrient solution, and relative root length (RRL) was determined at the 14-day-old stage to characterize genotypes for tolerance. Sixty-two traditional rice cultivars grown on lowland acid sulfate soil areas of Asia and West Africa were tested. Tolerant varieties ‘Azucena’, ‘IRAT104’, and ‘Moroberekan’, moderately sensitive ‘IR29’ and ‘IR43’, and sensitive ‘IR45’ and ‘IR1552’ were used to investigate the genetics of tolerance by diallel analysis. Of the 62 cultivars tested, only 3 were found to be sensitive to A l toxicity. Among the tolerant cultivars identified, 11 (‘Siyam Kuning’, ‘Gudabang Putih’, ‘Siyam’, ‘Lemo’, ‘Khao Daeng’, ‘Siyamhalus’, ‘Bjm-12’, ‘Ketan’, ‘Seribu Gantang’, ‘Bayer Raden Rati’, and ‘Padi Kanji’) were found to possess higher levels of tolerance than the improved tolerant upland cultivar ‘IRAT104’. Diallel analysis revealed that high RRL is governed by both additive and dominance effects with a preponderance of additive effects. The trait exhibited partial dominance, and one group of genes was detected. Heritability was high, and environmenal effects were low. Findings suggest that when breeding for A1 toxicity tolerance, selection can be made in early generations. The pedigree method of breeding would be suitable. Combining ability analysis revealed the importance of both general combining ability (GCA) and specific combining ability (SCA) in the genetics of A1 toxicity tolerance in rice. GCA was more prevalent than SCA. Tolerant parens ‘Azucena’, ‘IRAT104’, and ‘Moroberekan’ were the best general combiners. The presence of reciprocal effects among crosses suggested the proper choice of parents in hybridization programs. Results indicated that ‘Azucena’, ‘IRAT 104’, and ‘Moroberekan’ should be used as the female in crosses for A1 toxicity tolerance.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 25
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 93 (1996), S. 932-940 
    ISSN: 1432-2242
    Keywords: Genetics ; Adult-plant ; Blackleg resistance ; Brassica napus ; Leptosphaeria maculans ; Australian cultivar
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The genetic control of adult-plant blackleg [Leptosphaeria maculans (Desm.) Ces. et De Not.] resistance in rapeseed (Brassica napus L.) was studied in the F2 and first-backcross populations of the cross “Maluka” (blackleg-resistant) x “Niklas” (highly susceptible). A L. maculans isolate possessing high levels of host specificity (MB2) was used in all inoculations. Resistance/susceptibility was evaluated using three separate measures of crown-canker size, i.e. the percentage of crown girdled (%G), external lesion length (E) and internal lesion area (%II). Disease severity scores for the F2 and first-backcross populations based on E and %II gave discontinuous distributions, indicating major-gene control for these measures of resistance; but those for %G were continuous, indicating quantitative genetic control for this measure. Chi-square tests performed on the (poorly-defined) resistance classes, based on E, in the F2 and first-backcross populations indicated the likelihood for resistance being governed by a single, incompletely dominant major gene. Although the distributions of the F2 and first-backcross populations, based on%II, were clearly discontinuous, the observed segregation ratios for resistance and susceptibility did not fit any of the numerous Mendelian ratios which were considered. Differences in inheritance of resistance according to the assessment method and blackleg isolate used, were discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 26
    ISSN: 1573-0905
    Keywords: Differential diagnosis ; Etiology ; Genetics ; Mathematics performance ; Reading disability ; Twins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Education
    Notes: Abstract In order to assess the etiology of reading disability as a function of mathematics performance, data from 168 monozygotic (MZ) and 127 same-sex dizygotic (DZ) twin pairs in which at least one member of each pair was reading-disabled were subjected to quantitative genetic analyses. MZ and DZ concordance rates for reading disability were computed for different levels of mathematics performance, and reading performance data were fitted to an extension of the basic multiple regression model for the analysis of selected twin data. Results of these analyses suggest that genetic factors may be especially salient as a cause of reading disability in children with borderline deficits in mathematics performance: thus, mathematics performance may be a valid dimension for diagnosing subtypes of reading disability.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 27
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 12 (1996), S. 1677-1702 
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: No Abstract
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 28
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 12 (1996), S. 1647-1675 
    ISSN: 0749-503X
    Keywords: yeast ; phosphorylation ; protein phosphatase ; PP1 ; PP2A ; PP2B ; calcineurin ; Sit4 ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Since the isolation of the first yeast protein phosphatase genes in 1989, much progress has been made in understanding this important group of proteins. Yeast contain genes encoding all the major types of protein phosphatase found in higher eukaryotes and the ability to use powerful genetic approaches will complement the wealth of biochemical information available from other systems. This review will summarize recent progress in understanding the structure, function and regulation of the PPP family of protein serine-threonine phosphatases, concentrating on the budding yeast Saccharomyces cerevisiae.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 29
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 12 (1996), S. 1635-1646 
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: No Abstract
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 30
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 12 (1996), S. 1607-1633 
    ISSN: 0749-503X
    Keywords: Yeast ; glycolysis ; TCA cycle ; sugar metabolism ; metabolic engineering ; pyruvate decarboxylase ; pyruvate carboxylase ; pyruvate dehydrogenase complex ; alcoholic fermentation ; Crabtree effect ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In yeasts, pyruvate is located at a major junction of assimilatory and dissimilatory reactions as well as at the branch-point between respiratory dissimilation of sugars and alcoholic fermentation. This review deals with the enzymology, physiological function and regulation of three key reactions occurring at the pyruvate branch-point in the yeast Saccharomyces cerevisiae: (i) the direct oxidative decarboxylation of pyruvate to acetyl-CoA, catalysed by the pyruvate dehydrogenase complex, (ii) decarboxylation of pyruvate to acetaldehyde, catalysed by pyruvate decarboxylase, and (iii) the anaplerotic carboxylation of pyruvate to oxaloacetate, catalysed by pyruvate carboxylase. Special attention is devoted to physiological studies on S. cerevisiae strains in which structural genes encoding these key enzymes have been inactivated by gene disruption.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 31
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 12 (1996), S. 1603-1606 
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: No Abstract
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 32
    Electronic Resource
    Electronic Resource
    Springer
    Sexual plant reproduction 7 (1994), S. 290-296 
    ISSN: 1432-2145
    Keywords: Secale cereale ; Polyembryony ; Chromosome mosaics ; Rye ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We have obtained one plant regenerated from rye tissue culture which showed a high percentage of polyembryonic seeds in its progeny. The mutation inducing the development of extra embryos is also influencing erroneous cell division, mitosis and meiosis. The genetic analysis indicated that the aptitude for polyembryonic seed formation is a heritable trait controlled by a dominant gene. However, for expression of the phenotype the female parent should have a specific cytoplasm.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 33
    ISSN: 1432-2242
    Keywords: Breeding ; Helminthosporium turcicum ; RFLP ; QTLs ; Disease-resistance ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract RFLPs were used to investigate components of host-plant response to Exserohilum turcicum in 150 unselected F2∶3 lines of a B52/Mo17 maize population. Following inoculation with spore suspensions of the pathogen (race 0), components of disease development were measured and then quantitative trait mapping was performed to identify the location and effects of quantitative trait loci (QTLs) determining host-plant response. Components of interest were the average number of lesions per leaf, the average percent leaf tissue diseased (severity) and the average size of lesions (cm2). Based on a LOD threshold of 2.31 (P〈0.05), the number of lesions appears to be associated with QTLs on chromosomes 1S, 3L, 5S. Severity was associated with analogous regions and, in addition, QTLs on chromosomes 7L and 8L. Most QTLs, for either of these two components, involve additive gene action and partial dominance or overdominance. In contrast, lesion size was associated with QTLs on chromosomes 7L and 5L; recessive gene action may be involved at 7L.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 34
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 89 (1994), S. 959-963 
    ISSN: 1432-2242
    Keywords: Sugarcane ; Polyploidy ; Genetics ; Evolution ; Breeding ; DNA markers ; Arbitrarily primed PCR ; RAPD markers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Recent work has revealed random chromosome pairing and assortment in Saccharum spontaneum L., the most widely distributed, and morphologically and cytologically variable of the species of Saccharum. This conclusion was based on the analysis of a segregating population from across between S. spontaneum ‘SES 208’ and a spontaneously-doubled haploid of itself, derived from anther culture. To determine whether polysomic inheritance is common in Saccharum and whether it is observed in a typical biparental cross, we studied chromosome pairing and assortment in 44 progeny of a cross between euploid, meiotically regular, 2n=80 forms of Saccharum officinarum ‘LA Purple’ and Saccharum robustum ‘ Mol 5829’. Papuan 2n=80 forms of S. robustum have been suggested as the immediate progenitor species for cultivated sugarcane (S. officinarum). A total of 738 loci in LA Purple and 720 loci in Mol 5829 were amplified and typed in the progeny by arbitrarily primed PCR using 45 primers. Fifty and 33 single-dose polymorphisms were identified in the S. officinarum and S. robustum genomes, respectively (χ 2 at 98%). Linkage analysis of single-dose polymorphisms in both genomes revealed linkages in repulsion and coupling phases. In the S. officinarum genome, a map hypothesis gave 7 linkage groups with 17 linked and 33 unlinked markers. Four of 13 pairwise linkages were in repulsion phase and 9 were in coupling phase. In the S. robustum genome, a map hypothesis gave 5 linkage groups, defined by 12 markers, with 21 markers unlinked, and 2 of 9 pairwise linkages were in repulsion phase. Therefore, complete polysomic inheritance was not observed in either species, suggesting that chromosomal behavior is different from that observed by linkage analysis of over 500 markers in the S. spontaneum map. Implications of this finding for evolution and breeding are discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 35
    Electronic Resource
    Electronic Resource
    Springer
    Pediatric cardiology 15 (1994), S. 198-200 
    ISSN: 1432-1971
    Keywords: Subaortic stenosis ; Congenital heart disease ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The first case of multiple family members with discrete subaortic membrane and no other congenital defects is presented. One family member presents with findings suggesting a forme fruste of this disease. Increased surveillance of family members of individuals with discrete subaortic membrane is warranted, as the clinical findings of mild subaortic obstruction may be indistinguishable from those of an innocent flow murmur.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 36
    Electronic Resource
    Electronic Resource
    Springer
    Pediatric cardiology 15 (1994), S. 201-203 
    ISSN: 1432-1971
    Keywords: Tricuspid atresia ; Tricuspid hypoplasia ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Occurrence of a similar cardiac malformation in multiple family members has been reported for many lesions. Neither tricuspid atresia nor tricuspid annular hypoplasia and tricuspid atresia and one case of tricuspid annular hypoplasia with an atrial septal defect in siblings. The findings in this family suggest an autosomal recessive pattern of inheritance for abnormal tricuspid valve morphogenesis.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 37
    Electronic Resource
    Electronic Resource
    Springer
    Journal of molecular medicine 72 (1994), S. 409-413 
    ISSN: 1432-1440
    Keywords: Myotonic dystrophy ; Limb girdle muscular dystrophy ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A family is reported in which a 29-year-old woman showed the clinical features of myotonic dystrophy while her 26-year-old brother presented with the clinical picture of limb girdle syndrome. In the affected female, direct genetic testing for the specific myotonic dystrophy mutation on chromosome 19 revealed abnormal expansion of a repeat unit containing the three nucleotides cytosine, thymine, and guanine (CTG) — typical for myotonic dystrophy — while her diseased brother displayed two normal alleles. This supports the hypothesis of the extremely rare occurrence of two clinically and genetically different myopathies in one family. Genetic analysis of six other family members showed that the father of the diseased siblings as well as all of his three brothers and sisters had a pathological CTG repeat expansion, and that the other two family members tested had a normal allelic pattern. The number of CTG repeats in the diseased women was approximately tenfold higher than in her asymptomatic relatives who revealed an abnormal allelic pattern. The increase in CTG repeats with transmission to a subsequent generation in this family was paralleled by a dramatic increase in the severity of myotonic dystrophy.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 38
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 50 (1994), S. 429-437 
    ISSN: 1420-9071
    Keywords: Genetics ; ecology ; DNA-transfer ; conjugation ; transformation ; transduction ; transposons ; dormant cells ; epilithon ; microbial colonisation ; symbiosis ; virus resistance ; biosafety ; release of genes ; insults to humanity ; evolution ; biodiversity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Genetic ecology is the extension of our modern knowledge in molecular genetics to studies of viability, gene expression and gene movements in natural environments like soils, aquifers and digestive tracts. In such milieux, the horizontal transfer of plasmid-borne genes between phylogenetically distant species has already been found to be much more frequent than had been expected from laboratory experience. For the study of exchanges involving chromosomally-located genes, more has to be learned about the behaviour of transposons in such environments. The results expected from studies in genetic ecology are relevant for considerations of evolution, biodiversity and biosafety. The role of this new field of research in restoring popular confidence in science and in its biotechnological applications is stressed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 39
    ISSN: 1432-0533
    Keywords: Key words: Amyotrophic lateral sclerosis ; Neuropathology ; Posterior column involvement ; Genetics ; Superoxide dismutase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Several missense mutations within exons 1, 2, 4 and 5 of the gene for Cu/Zn-binding superoxide dismutase (SOD1) have been discovered to be involved in the development of chromosome 21q-linked familial amyotrophic lateral sclerosis (FALS). We describe here an autopsied patient with FALS, in whom we have recently identified a novel missense mutation in exon 1 of the SOD1 gene. The neuropathological findings were compatible with those described previously in patients with FALS with posterior column involvement. This suggests that mutations of the SOD1 gene may be responsible for this form of FALS.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 40
    ISSN: 1432-0533
    Keywords: Key words     Primitive neuroepithelial tumor ; Desmoplastic small cell tumor ; Brain tumor of infancy ; Immunocytochemistry ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract      We describe a case of a desmoplastic brain tumor which was initially resected from the right fronto-temporal region in a 2 year-old boy. This nodular, calcified tumor was vascularized by the internal carotid artery and the middle meningeal artery branches. Grossly, it contained several mucoid cysts. Light microscopy showed cords or nests of small cuboidal cells surrounded by a loose connective tissue and desmoplasic areas containing fibers and spindle cells. The cuboidal cells expressed epithelial, neuronal and neuroendocrine markers. Some foci of spindle cells showed glial differentiation. The tumor recurred 16 months later and displayed some characteristics of the small cell neuroepithelial component, mitoses being conspicuous. Electron microscopy revealed undifferentiated clear cells, some containing neurosecretory granules. Karyotyping demonstrated the following formula: 〈 15 〉 46, t(8;11) (q13; q11). The chromosome 11 breakpoint was different from that described in Ewing's sarcoma. This isolated translocation has not been previously reported to our knowledge. These unusual features lead us to report this case and to discuss its pathogenesis.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 41
    ISSN: 1432-0533
    Keywords: Amyotrophic lateral sclerosis ; Neuropathology ; Posterior column involvement ; Genetics ; Superoxide dismutase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Several missense mutations within exons 1, 2, 4 and 5 of the gene for Cu/Zn-binding superoxide dismutase (SOD1) have been discovered to be involved in the development of chromosome 21q-linked familial amyotrophic lateral sclerosis (FALS). We describe here an autopsied patient with FALS, in whom we have recently identified a novel missense mutation in exon 1 of the SOD1 gene. The neuropathological findings were compatible with those described previously in patients with FALS with posterior column involvement. This suggests that mutations of the SOD1 gene may be responsible for this form of FALS.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 42
    ISSN: 1432-0428
    Keywords: Genetics ; diabetes mellitus ; mitochondria ; maternal ; deafness
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Non-insulin-dependent diabetes mellitus (NIDDM) has a strong genetic component and maternal factors have recently been implicated in disease inheritance. The mitochondrial myopathies are a group of diseases which often show maternal inheritance as a result of mtDNA defects; some patients have impaired glucose tolerance. Occasional families with maternally inherited diabetes and deafness associated with a deletion or point mutation of mtDNA have been reported. To assess the importance of mitochondrial gene defects in NIDDM, 150 unrelated diabetic subjects from Wales, UK and 68 unrelated patients with diabetes and at least one affected sibling from England, UK were studied. Southern blot analysis did not show any large mtDNA deletions or duplications. One patient had a mutation in the mitochondrial tRNAleu(UUR) gene at bp 3243. This mutation is commonly associated with the syndrome of mitochondrial encephalomyopathy, lactic acidosis and stroke like episodes (MELAS). Study of this patient and his siblings showed a distinct form of late-onset diabetes associated with nerve deafness but no clinical features of the MELAS syndrome. No diabetic subject was shown to have the mtDNA mutation at position 8344 (tRNAlys) which has previously been described in the syndrome of mitochondrial encephalomyopathy and red-ragged fibres (MERRF). The role of other mitochondrial gene defects in diabetes and the pathophysiological basis of glucose intolerance in patients with the MELAS mutation requires further elucidation.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 43
    Electronic Resource
    Electronic Resource
    Springer
    Journal of biomedical science 1 (1994), S. 201-203 
    ISSN: 1423-0127
    Keywords: Hypertension ; Eicosanoid ; Rat ; Genetics ; Kidney
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The present paper reviews the evidence for a possible involvement of renal eicosanoids in the pathophysiology of high blood pressure in genetically hypertensive rats of the Lyon strain. Both in vivo and in vitro experiments suggest that an increased ability to synthesize the vasoconstrictor prostaglandin H2 and/or thromboxane A2 in renal vessels (1) acts as an autocrine amplifier of pressor agents and (2) may contribute to resetting the pressure natriuresis curve which is a prerequisite for the development and maintenance of hypertension.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 44
    Electronic Resource
    Electronic Resource
    Springer
    European journal of pediatrics 153 (1994), S. 372-377 
    ISSN: 1432-1076
    Keywords: Epilepsy ; Absences ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Clinical and EEG family data of 140 cases with early childhood epilepsy with absences are presented. The aim of the study was to evaluate, whether the occurrence of generalized tonic clonic seizures (GTCS) as a presenting symptom might correlate with family data, i.e. whether there are indications of heterogeneity. One hundred and forty cases were selected from the epilepsy family data base of the Neuropaediatric Department. The selection parameter was epilepsy with absences manifesting between the 1 st and 5th year of age. The incidence of seizures was evaluated in siblings, parents and parents' siblings. EEG records were available from 103 parents and 106 siblings. The analysis supports the assumption of heterogeneity within early childhood absence epilepsy. Parents and their sibs of cases manifesting with GTCS had seizures twice as often than parents and their sibs in the non-GTCS group. In the affected relatives of the GTCS group early onset GTCS prevailed, whereas in the relatives of the non-GTCS group absences were found more frequently. The EEG of relatives showed elevated incidences of spikes and waves and photosensitivity in both groups, indicating common genetic factors. In parents of the non-GTCS group, however, EEG pathology was significantly more frequent than in parents of the GTCS group. Comparing EEG pathology in parents with seizure risk in siblings, evidence for maternal preponderance in transmission of the seizure liability was found. Mothers' EEG seems to be the best predictor of the seizure risk in probands' siblings. Early childhood epilepsy with absences can be regarded as an intermediate type, showing overlap with early onset GTCS and myoclonic astatic epilepsy on the one side and with childhood absence epilepsy on the other.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 45
    ISSN: 1432-0428
    Keywords: Genetics ; haplotype ; HLA-A ; HLA-DQ ; HLA-DR ; tumour necrosis factor ; diabetes mellitus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In Finland the haplotype A2, Cw1, B56, DR4, DQ8 is the third most common haplotype in insulin-dependent diabetic (IDDM) patients and has the highest haplotype-specific absolute risk for IDDM. Cw1, B56, DR4, DQ8 haplotypes containing HLA-A alleles other than A2 are infrequent in the population and are not associated with IDDM. Comparison of the A2 and non-A2 haplotypes at the DNA level showed that they were identical at HLA-B,-DR, and -DQ loci. Evidence that class I alleles confer susceptibility to IDDM was obtained from the two HLA-C, -B, -DR and -DQ haplotypes most frequently found in IDDM patients in Finland. A24, A3 and A2 on the Cw3, B62, DR4, DQ8 haplotype, and A28, A2 and A1 on the Cw7, B8, DR3, DQ2 were all found to be associated with IDDM. In Finland these seven haplotypes, including A2, Cw1, B56, DR4, DQ8, account for 33% of diabetic haplotypes and 10.3% of non-diabetic haplotypes (p〈0.00001). The contribution of the class I region to IDDM susceptibility was also apparent in those IDDM patients lacking the disease-predisposing class II alleles. Significantly more non-DR3/non-DR4 IDDM patients (47 of 55) possessed two of the IDDM-associated HLA-A alleles compared to non-DR3/non-DR4 control subjects (40 of 58; p=0.038). Moreover, IDDM patients confirmed by oligotyping as unable to form a ‘diabetes-susceptibility’ DQ heterodimer, tended to possess two diabetes-associated HLA-A alleles (12 of 13) compared to control subjects (12 of 20; p=0.056).
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 46
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 88 (1994), S. 754-758 
    ISSN: 1432-2242
    Keywords: Potato breeding ; Potato leaf roll virus ; Virus resistance ; Major gene resistance ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The concentration of potato leaf roll virus (PLRV), as measured by a quantitative enzyme-linked immunosorbent assay, in the foliage of potato plants (Solanum tuberosum) of cv ‘Maris Piper’ with secondary infection was 2900 ng/g leaf, whereas in clones G7445(1) and G7032(5) it was 180 ng/g leaf and 120 ng/g leaf, respectively. To examine the genetic control of resistance to PLRV multiplication, reciprocal crosses were made between the susceptible cultivar ‘Maris Piper’ and the two resistant clones, and the three parents were selfed. Seedling progenies of these families were grown to generate tubers of individual genotypes (clones). Clonally propagated plants were graft-inoculated, and their daughter tubers were collected and used to grow plants with secondary infection in which PLRV concentration was estimated. The expression of resistance to PLRV multiplication had a bimodal distribution in progenies from crosses between ‘Maris Piper’ and either resistant clone, and also in progeny from selfing the resistant parents, with genotypes segregating into high and low virus titre groups. Only the progeny obtained from selfing ‘Maris Piper’ did not segregate, all genotypes being susceptible to PLRV multiplication. The pattern of segregation obtained from these progenies fits more closely with the genetical hypothesis that resistance to PLRV multiplication is controlled by two unlinked dominant complementary genes, both of which are required for resistance, than with the simpler hypothesis that resistance is conferred by a single dominant gene, as published previously.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 47
    ISSN: 1432-2242
    Keywords: Genetics ; Disease resistance ; Monocots
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract An F2 oat population was produced by crossing the diploid (n=7) species Avena strigosa (CI 3815) with A. wiestii (CI 1994), resistant and susceptible, respectively, to 40 isolates of Puccinia coronata, the causal agent of crown rust. Eighty-eight F2 individuals were used to construct an RFLP linkage map representing the A genome of cultivated hexaploid oat. Two hundred and eight RFLP loci have been placed into 10 linkage groups. This map covers 2416 cM, with an average of 12 cM between RFLP loci. Eighty-eight F3 lines, derived from F2 individuals used to construct the map, were screened for resistance to 9 isolates of P. coronata. One locus, Pca, was found to confer a dominant resistance phenotype to isolates 203, 258, 263, 264B, 290, 298, 325A, and 345. Pca also conferred resistance to isolate 276; however, an unlinked second gene may also be involved.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 48
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 89 (1994), S. 313-317 
    ISSN: 1432-2242
    Keywords: Genetics ; Rice ; Phosphorousefficiency ; Diallel analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The inheritance of phosphorous (P) — deficiency tolerance in rice was investigated by a sevenparent diallel. The parent materials involved were four P-efficient (IR20, IR54, IR28, and Mahsuri), one moderately P-efficient (TN1), and two P-inefficient (IR31406333-1 and IR34686-179-1-2-1), genotypes. Relative tilering ability (RTA) under P-deficient and P-supplemented soil conditions was the parameter used in determining the tolerance level of the different genotypes. Diallel graph analysis revealed that tolerant parents have an excess of recessive genes, while moderate and susceptible parents possess more dominant genes. Genetic-component analysis suggested that both additive and dominance gene effects are involved in the inheritance of P-deficiency tolerance in rice. The trait exhibited over doiminance as confirmed by the graphical analysis. Narrow-sense heritability of the trait was moderate (0.50) and environmental effects were low. Both the general combining ability (GCA) and the specific combining ability (SCA) were significant, but GCA was more prevalent than SCA. Tolerant parents exhibited a high GCA whereas susceptibles have a very poor GCA, suggesting that tolerant parents were mostly enriched in additive genes and susceptible parents in non-additive genes. Crosses involving two high general combiners showed low SCA effects whereas crosses between poor general combiners manifested highly-significant SCA values.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 49
    ISSN: 1530-0358
    Keywords: Desmoids ; Genetics ; Chemotherapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract PURPOSE: The aim of this study was to describe the natural history and management of surgically unresectable intra-abdominal desmoid tumors in two patients with Gardner's syndrome from two unrelated families, where each had failed on conventional therapy. METHODS: Two patients with Gardner's syndrome were placed on a chemotherapy regimen which included doxorubicin (90 mg/m2) and dacarbazine (900 mg/m2) in divided doses over four days of continuous infusion. Their progress on chemotherapy was assessed by abdominal computerized tomography and laparoscopy. RESULTS: The computerized abdominal tomography scans proved difficult to interpret because of adhesions and matted small bowel resulting from the patients original colectomies. These findings made it difficult to differentiate postoperative changes from residual desmoid tumor. Second-look laparotomy in such patients was contraindicated as this may predispose to further desmoid production. Laparoscopy disclosed a complete response to this chemotherapy. Nevertheless, we had an iatrogenic small bowel perforation in one of these patients. Each patient showed a complete response to chemotherapy. CONCLUSION: Surgical resection remains the first-line treatment of intra-abdominal desmoid tumors. However, doxorubicin/ dacarbazine chemotherapy on a clinical trial basis may be indicated in patients whose intra-abdominal desmoid is unresectable, or who have failed to respond to treatment with hormones (tamoxifen, Toremifene), steroids (prednisone), and nonsteroidal anti-inflammatory agents (Clinoril®; Merck & Co., Inc., West Point, PA).
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 50
    ISSN: 1437-160X
    Keywords: Systemic lupus erythematosus ; Recombinant U1-nRNP proteins ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To investigate a possible involvement of HLA-class II alleles in the genetic predisposition for the formation of anti-U1-nRNP antibody in systemic lupus erythematosus (SLE), genomic DNA of 178 patients was typed for the DRB1, DQA1 and DQB1 alleles using a polymerase chain reaction (PCR) and non-radioactive-oligonucleotide typing. Antibodies against recombinant U1-nRNP proteins (U1-A- U1-C-and 70K-protein) were determined by ELISA. Anti-U1-C antibody was found in 26 (14.7%), anti-U1-A in 34 (19.2%) and anti-70K in 17 (9.6%) patients. A joint occurrence was observed for these antibodies against the recombinant U1-nRNP proteins: anti-U1-C and anti-U1-A antibodies occurred together more frequently than alone and than together with anti-U1-70K antibodies. The frequency of DRB1 * 04 was slightly increased in the patients with anti-U1-C as compared to the patients without anti-U1-C (P〈0.05, Pcorr=n.s., RR=2.4). The DQA1 * 0301 allele, which is in linkage disequilibrium with DRB1 * 04, is found more frequently in anti-U1-C-positive than in antibody-negative patients. The DQB1 * 0303 allele, detected in 12 of 176 SLE patients, was absent in the patients with any of the antibodies against the U1-nRNP proteins. All these deviations may be due to chance alone. We concluded that the presence of antibodies against recombinant U1-nRNP proteins was not significantly associated with any HLA DRB1, DQA1 and DQB1 allele in our group of SLE patients.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 51
    ISSN: 1432-1459
    Keywords: Multiple sclerosis Epidemiology ; Immigrants Environment ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The incidence and prevalence of multiple sclerosis (MS) were compared, controlling for age, in native-born Israelis of different origins and in immigrants to Israel. This comparison was carried out in two populations, countrywide and in Jerusalem. In the countrywide population, ascertainment was based mainly on hospitalizations; it included 252 patients who were native-born and 150 who had immigrated from Africa-Asia (AA immigrants). The 89 MS patients of Jerusalem also included patients diagnosed in outpatient clinics. In native-born Israelis whose father was born in Europe-America (I-EA), the incidence and prevalence of MS were found to be as high as or even higher than that found previously in immigrants from Europe-America. Among native-born Israelis whose father was born in Africa or Asia (I-AA), the yearly age-adjusted incidence and prevalence rates were found to be 1.4- to 1.8-fold higher than among AA immigrants, pointing to environmental factors. The incidence and prevalence rates in the I-EA were 1.2- to 1.6-fold higher than in the I-AA, pointing to genetic factors. These results seem to point to both environmental and genetic factors in the aetiology of MS. Further research is needed, however, to disentangle the genetic factors from possible environmental differences in the two ethnic groups.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 52
    Electronic Resource
    Electronic Resource
    Springer
    Journal of neurology 241 (1994), S. 487-491 
    ISSN: 1432-1459
    Keywords: Juvenile absence epilepsy ; Valproate ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Fifteen patients aged 11–25 years (mean 15.37, SD 3.89) suffering from juvenile absence epilepsy are presented. Only 3 (20%) had absences (AS) as the only seizure type, 12 (80%) had associated generalized tonic-clinic seizures (GTCS) and in the remaining 3 with absences and GTCS there was also sporadic myoclonus. We found a higher frequency of AS in our patients by clinical history and video-EEG than has been previously reported. In our patients the mean age of onset in years was 11.4, SD 1.24 for AS, 13.12, SD 2.31 for GTCS and 12.5, SD 2.18 for myoclonus. The correct diagnosis was not made on referrals for any of the patients. It took an average of 3–5.5 years from the onset of the AS (range: 6–120 months) and 2 years from the occurrence of GTCS (average: 1–72 months) to make the correct diagnosis and institute proper treatment, which was valproic acid (VPA). The GTCS were controlled in all patients whereas AS continued in 6 (40%), but to a significantly lesser degree. The frequency and the duration of the GTCS before the start of VPA treatment seemed to have an adverse effect on AS control. We documented no circadian rhythm in either AS or the GTCS, except in 2 patients who had AS and GTCS mainly when they awoke in the morning. The sample size was too small to perform a proper genetic study, though a positive history of epilepsies of mixed types was obtained in 35.7% of the parents and the siblings of the probands.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 53
    Electronic Resource
    Electronic Resource
    Springer
    European archives of psychiatry and clinical neuroscience 244 (1994), S. 138-140 
    ISSN: 1433-8491
    Keywords: Parity ; Genetics ; Diathesis-stress model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract As part of a follow-up and family study of post-partum psychoses, this episode of illness being the first leading to psychiatric hospitalisation, patients with puerperal episodes (PE) and nonpuerperal episodes (NPE) of illness in the long-term course (n=79) were compared to patients with PE only (n=40). Few differences were found. Relatives of patients with PE only had a lower morbidity risk for functional psychoses than relatives of patients with PE and NPE. A favourable course of illness in the presence of a low genetic predisposition may be expected, according to the diathesis-stress model of functional psychoses.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 54
    Electronic Resource
    Electronic Resource
    Springer
    European journal of epidemiology 10 (1994), S. 317-324 
    ISSN: 1573-7284
    Keywords: Epidemiology ; Genetics ; Oral clefts ; Registers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Epidemiological and genetic variables for oral clefts were analysed for the years 1981–1989 in a case-control study of congenital malformations in the Emilia Romagna, Veneto, and Friuli regions, and in the Trento and Bolzano hospitals. Birth prevalence for all cases of cleft lip with or without cleft palate (CL(P)) was 8.2 per 10,000 births, and that for cleft palate only (CP) was 6.1 per 10,000. Coexisting abnormalities were found in 23% of CL(P) cases and in 43% of CP. No clusters in time or space were detected. For isolated clefts, a predominance of males among CL(P) and of females among CP was found; epilepsy was the only maternal risk factor correlated with clefts, and an association between clefting and consanguinity was found. Empirical recurrence risks were calculated in both isolated CL(P) and CP.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 55
    ISSN: 1432-2242
    Keywords: Maize ; Restriction fragment length polymorphisms (RFLPs) ; Qualitative and quantitative inheritance ; Plant breeding ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Restriction fragment length polymorphisms (RFLPs) and one morphological marker were used to investigate quantitative trait loci (QTL) for morphological and physiological traits evaluated on 150 F2∶3 maize (Zea mays L.) lines derived from the cross of elite U.S. Corn Belt inbreds Mo17 and H99. F2∶3 lines were grown in a replicated experiment and evaluated for plant and ear heights and flowering traits. QTL were identified for each trait, and genetic effects were determined. Estimated gene action for the flowering traits was predominantly overdominance. Both parents contributed toward increased values for anthesis and silk emergence. QTL for increased plant and ear heights were usually contributed by the taller parent, Mo17. Estimated gene action for these traits was mainly partial to overdominance. QTL for plant height were located in the vicinity of loci defined by alleles with qualitative effects on plant height.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 56
    ISSN: 1617-4623
    Keywords: Gene regulation ; Ribozyme ; npt-gene ; Transgenic tobacco ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A chimeric gene encoding a ribozyme under the control of the cauliflower mosaic virus (CaMV) 35S promoter was introduced into transgenic tobacco plants. In vivo activity of this ribozyme, which was designed to cleave npt mRNA, was previously demonstrated by transient expression assays in plant protoplasts. The ribozyme gene was transferred into transgenic tobacco plants expressing an rbcS-npt chimeric gene as an indicator. Five double transformants out of sixteen exhibited a reduction in the amount of active NPT enzyme. To measure the amount of ribozyme produced, in the absence of its target, the ribozyme and target genes were separated by genetic segregation. The steady-state concentrations of ribozyme and target RNA were shown to be similar in the resulting single transformants. Direct evidence for a correlation between reduced npt gene expression and ribozyme expression was provided by crossing a plant containing only the ribozyme gene with a transgenic plant expressing the npt gene under control of the 35S promoter, i.e. the same promoter used to direct ribozyme expression. The expression of npt was reduced in all progeny containing both transgenes. Both steady-state levels of npt mRNA and amounts of active NPT enzyme are decreased. In addition, our data indicate that, at least in stable transformants, a large excess of ribozyme over target is not a prerequisite for achieving a significant reduction in target gene expression.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 57
    Electronic Resource
    Electronic Resource
    Springer
    Behavioral ecology and sociobiology 35 (1994), S. 99-107 
    ISSN: 1432-0762
    Keywords: Key words Apis mellifera ; Genetics ; Drone production ; Allozymes ; Reproductive conflict
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Previously we reported that there are subfamily differences in drone production in queenless honey bee colonies, but these biases are not always explained by subfamily differences in oviposition behavior. Here we determine whether these puzzling results are best explained by either inadequate sampling of the laying worker population or reproductive conflict among workers resulting in differential treatment of eggs and larvae. Using colonies composed of workers from electrophoretically distinct subfamilies, we collected samples of adult bees engaged in the following behavior: “true” egg laying, “false” egg laying, indeterminate egg laying, egg cannibalism, or nursing (contact with larvae). We also collected samples of drone brood at four different ages: 0 to 2.5-h-old eggs, 0 to 24-h-old eggs, 3 to 8-day-old larvae, and 9 to 14-day-old larvae and pupae. Allozyme analyses revealed significant subfamily differences in the likelihood of exhibiting egg laying, egg cannibalism, and nursing behavior, as well as significant subfamily differences in drone production. There were no subfamily differences among the different types of laying workers collected from each colony, suggesting that discrepancies between subfamily biases in egg-laying behavior and drone production are not due to inadequate sampling of the laying worker population. Subfamily biases in drone brood production within a colony changed significantly with brood age. Laying workers had significantly more developed ovaries than either egg cannibals or nurses, establishing a physiological correlate for the observed behavioral genetic differences. These results suggest there is reproductive conflict among subfamilies and individuals within queenless colonies of honey bees. The implications of these results for the evolution of reproductive conflict, in both queenright and queenless contexts, are discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 58
    Electronic Resource
    Electronic Resource
    Springer
    Metabolic brain disease 9 (1994), S. 105-131 
    ISSN: 1573-7365
    Keywords: Alcoholism ; Genetics ; Endorphins ; Enkephalins ; Dynorphins ; Opioid ; Receptors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract At the present time alcoholism is recognized as a metabolic disease exhibiting the clinical features of craving for alcohol, loss of control over drinking, tolerance and physical dependence on alcohol, while both epidemiological and experimental studies have demonstrated that genetic factors may be important in determining whether an individual has a high or low vulnerability to develop alcoholism. Evidence also indicates that alcoholism is not characterized by a single gene single allele inheritance. Instead it seems that multiple genes and environmental factors interact to increase or decrease an individual's vulnerability to become an alcoholic. Current research is aimed at investigating whether certain behavioral, physiological and biochemical markers are highly associated with the incidence of alcoholism. Among the biochemical markers currently under investigation is the endogenous opioid system and its implication in mediating the reinforcing effects of ethanol. It is the objective of this manuscript to review current research on: (a) the interactions of ethanol with the endogenous opioid system at the molecular level; (b) the existence of genetically determined differences in the response of the endogenous opioid system to ethanol between subjects at high and low risk for excessive ethanol consumption, as well as between lines of animals showing preference or aversion for ethanol solutions; (c) the decrease of alcohol consumption following pretreatment with opioid antagonists; and (d) the possible use of specific opioid receptor antagonists together with behavioral therapy to modify drinking behavior, to control craving and to prevent relapse.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 59
    Electronic Resource
    Electronic Resource
    Springer
    Behavioral ecology and sociobiology 34 (1994), S. 117-409 
    ISSN: 1432-0762
    Keywords: Social insects ; Apis mellifera ; Division of labor ; Genetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Variability exists among worker honey bees for components of division of labor. These components are of two types, those that affect foraging behavior and those that affect life-history characteristics of workers. Variable foraging behavior components are: the probability that foraging workers collect (1) pollen only; (2) nectar only; and (3) pollen and nectar on the same trip. Life history components are: (1) the age the workers initiate foraging behavior; (2) the length of the foraging life of a worker; and (3) worker length of life. We show how these components may interact to change the social organization of honey bee colonies and the lifetime foraging productivity of individual workers. Selection acting on foraging behavior components may result in changes in the proportion of workers collecting pollen and nectar. Selection acting on life-history components may affect the size of the foraging population and the distribution of workers between within nest and foraging activities. We suggest that these components define possible sociogenic “pathways” through which colony-level natural selection can change social organization. These pathways may be analogous to developmental pathways in the morphogenesis of individual organisms because small changes in behavioral or life history components of individual workers may lead to major changes in the organizational structure of colonies.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 60
    Electronic Resource
    Electronic Resource
    Springer
    Behavioral ecology and sociobiology 35 (1994), S. 99-107 
    ISSN: 1432-0762
    Keywords: Apis mellifera ; Genetics ; Drone production ; Allozymes ; Reproductive conflict
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Previously we reported that there are subfamily differences in drone production in queenless honey bee colonies, but these biases are not always explained by subfamily differences in oviposition behavior. Here we determine whether these puzzling results are best explained by either inadequate sampling of the laying worker population or reproductive conflict among workers resulting in differential treatment of eggs and larvae. Using colonies composed of workers from electrophoretically distinct subfamilies, we collected samples of adult bees engaged in the following behavior: “true” egg laying, “false” egg laying, indeterminate egg laying, egg cannibalism, or nursing (contact with larvae). We also collected samples of drone brood at four different ages: 0 to 2.5-h-old eggs, 0 to 24-h-old eggs, 3 to 8-day-old larvae, and 9 to 14-day-old larvae and pupae. Allozyme analyses revealed significant subfamily differences in the likelihood of exhibiting egg laying, egg cannibalism, and nursing behavior, as well as significant subfamily differences in drone production. There were no subfamily differences among the different types of laying workers collected from each colony, suggesting that discrepancies between subfamily biases in egg-laying behavior and drone production are not due to inadequate sampling of the laying worker population. Subfamily biases in drone brood production within a colony changed significantly with brood age. Laying workers had significantly more developed ovaries than either egg cannibals or nurses, establishing a physiological correlate for the observed behavioral genetic differences. These results suggest there is reproductive conflict among subfamilies and individuals within queenless colonies of honey bees. The implications of these results for the evolution of reproductive conflict, in both queenright and queenless contexts, are discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 61
    Electronic Resource
    Electronic Resource
    Springer
    Behavioral ecology and sociobiology 34 (1994), S. 125-137 
    ISSN: 1432-0762
    Keywords: Social insects ; Apis mellifera ; Division of labor ; Genetics ; Nepotism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Three experiments were performed to determine whether brood care in honey bee colonies is influenced by colony genetic structure and by social context. In experiment 1, there were significant genotypic biases in the relative likelihood of rearing queens or workers, based on observations of individually labeled workers of known age belonging to two visually distinguishable subfamilies. In experiment 2, no genotypic biases in the relative likelihood of rearing drones or workers was detected, in the same colonies that were used in experiment 1. In experiment 3, there again were significant genotypic differences in the likelihood of rearing queens or workers, based on electrophoretic analyses of workers from a set of colonies with allozyme subfamily markers. There also was an overall significant trend for colonies to show greater subfamily differences in queen rearing when the queens were sisters (half- and super-sisters) rather than unrelated, but these differences were not consistent from trial to trial for some colonies. Results of experiments 1 and 3 demonstrate genotypic differences in queen rearing, which has been reported previously based on more limited behavioral observations. Results from all three experiments suggest that genotypic differences in brood care are influenced by social context and may be more pronounced when workers have a theoretical opportunity to practice nepotism. Finally, we failed to detect persistent interindividual differences in bees from either subfamily in the tendency to rear queen brood, using two different statistical tests. This indicates that the probability of queen rearing was influenced by genotypic differences but not by the effect of prior queen-rearing experience. These results suggest that subfamilies within a colony can specialize on a particular task, such as queen rearing, without individual workers performing that task for extended periods of time.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 62
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 1-11 
    ISSN: 0749-503X
    Keywords: Schizosaccharomyces pombe ; Golgi body ; protein transport ; secretion ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Schizosaccharomyces pombe was treated with either cycloheximide or anisomycin at levels sufficient to inhibit 〉95% of protein synthesis for periods upon to 3 h, equivalent to one cell cycle. Treatment for as little as 1 h caused significant loss of the Golgi apparatus by both immunofluorescence and electron microscopy. The loss was quantitated by stereology on electron micrographs. Nearly 90% of the stacked Golgi was lost over a 3 h period. No other intracellular membrane compartment seemed to be affected. Measurement of enzyme activities confirmed these observations. The activity of a resident of the Golgi apparatus, α-1,2 galactosyltransferase, was reduced over this time, whereas the endoplasmic reticulum marker, BiP, and the cytoplasmic enzyme, hexokinase, were unaffected. The morphological changes associated with cycloheximide addition were reversed on its removal, though there was a lag before cells recommenced growth or secretion of the enzyme, acid phosphatase.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 63
    ISSN: 0749-503X
    Keywords: Genome sequencing ; Saccharomyces cerevisiae ; chromosome XI ; MBR1 ; GTPase-activating protein ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We present the DNA sequence analysis of a region covering a 3·5 kb EcoRI fragment from the left arm of chromosome XI from Saccharomyces cerevisiae. This region contains five open reading frames (ORFs) which code for proteins of greater than 100 amino acids. ORF YKL425 codes for the previously sequenced Mbr1 (Valens et al., 1991; Daignan-Fornier et al., 1993) which participates in mitochondrial biogenesis. YKL424 has identity with a GTPase-activating protein of higher eukaryotes. The three remaining ORFs have no identity to known proteins within the databases screened and are not assigned ORF numbers as they are completely contained with ORFs YKL424 and YKL425. This sequence has been entered in the EMBL Data Library under Accession Number X75561.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 64
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994) 
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 65
    ISSN: 0749-503X
    Keywords: Heterologous gene expression ; levansucrase precursor ; Bacillus subtilis ; yeast ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Levansucrase, a Bacillus subtilis extracellular enzyme, was not secreted in the culture medium when produced in yeast. The protein accumulated inside the cell in its precursor form which represented 0·3% of total proteins. The absence of any post-translational modifications, such as signal sequence cleavage or addition of N-linked sugars, indicated that this protein did not enter the reticulum secretion pathway.Direct observation of the cells by confocal laser scanning microscopy showed that levansucrase was associated with the cytoplasmic membrane. Subcellular fractionation experiments revealed that levansucrase precursor form is associated with membranes through weak ionic interactions. The purified precursor displayed the same catalytic properties as levansucrase secreted by B. subtilis. Thus yeast could be used as a source of levansucrase precursor allowing its isolation as a pure form on a milligram scale.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 66
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 271-274 
    ISSN: 0749-503X
    Keywords: Genome sequencing ; Saccharomyces cerevisiae ; chromosome III ; telomeres ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A comparison of the sequences of telomere regions from several yeast chromosomes revealed an apparent cloning artifact for the right end of chromosome III. An integrating vector containing G1-3T telomere sequences was used to clone the right end of chromosome III from a strain related to S288C. The sequence of this clone confirmed that the published sequence was incorrect and demonstrated that the right telomere region of chromosome III is similar to other telomeres.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 67
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; Saccharomyces douglasii ; evolution ; ARG4 ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A 3·6 kb DNA fragment from Saccharomyces douglasii, containing the ARG4 gene, has been cloned, sequenced and compared to the corresponding region from Saccharomyces cerevisiae. The organization of this region is identical in both yeasts. It contains besides the ARG4 gene, another complete open reading frame (ORF) (YSD83) and a third incomplete one (DED81). The ARG4 and the YSD83 coding regions differ from their S. cerevisiae homologs by 8.1% and 12·5%, respectively, of base substitutions. The encoded proteins have evolved differently: amino acid replacements are significantly less frequent in Arg4 (2·8%) than in Ysc83 (12·4%) and most of the changes in Arg4 are conservative, which is not the case for Ysc83. The non-coding regions are less conserved, with small AT-rich insertions/deletions and 20% base substitutions. However, the level of divergence is smaller in the aligned sequences of these regions than in silent sites of the ORFs, probably revealing a higher degree of constraints. The Gcn4 binding site and the region where meiotic double-strand breaks occur, are fully conserved. The data confirm that these two yeasts are evolutionarily closely related and that comparisons of their sequences might reveal conserved protein and DNA domains not expected to be found in sequence comparisons between more diverged organisms.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 68
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 371-376 
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; NES24 ; chromosome XIII ; neomycin ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have cloned NES24 using a temperature-sensitive nes24-1 mutant as a host and sequenced a 3162 bp XhoI-EcoRI DNA fragment containing the NES24 gene. Computer analysis revealed that this segment contains a 1806 bp open reading frame which is needed for complementation of the nes24-1 mutation. We found SUP8 in the region upstream of the NES24 gene, placing the NES24 gene on chromosome XIII. A protein homology search indicated that NES24 encodes a new protein. The disruption of the NES24 gene resulted in temperature-sensitive growth. The sequence has been deposited in DDBJ/EmBL/GenBank data bases under Accession Number D15052.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 69
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; Chromosome V ; Monomeric G-protein ; Rab protein ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A Saccharomyces cerevisiae sequence cloned by serendipity was found to encode a protein that is a new member of the Ypt/Rab monomeric G-protein family. This sequence shows high homology to the yeast genes SEC4 and YPT1 and, like SEC4 and YPT1, is essential for viability. The sequence was localized to chromosome V based upon hybridization to pulse-field gel-separated yeast chromosomes. The sequence has been deposited in the GenBank data library under Accession Number L17070.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 70
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994) 
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 71
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 451-461 
    ISSN: 0749-503X
    Keywords: RAS-cAMP pathway ; CDC25 family ; cell division cycle mutation ; S. cerevisiae ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have identified MS12 as a gene of Saccharomyces cerevisiae which, when on a multicopy vector, suppresses the heat shock sensitivity caused by the loss of the IRA1 product, a negative regulator of the RAS protein. The multicopy MSI2 also suppresses the heat shock sensitivity of cells with the RAS2val19 mutation but not those with the bcy1 mutation, suggesting that the MSI2 protein may interfere with the activity of the RAS protein. The sequence analysis of MSI2 reveals that it is identical to LTE1 belonging to the CDC25 family: CDC25, SCD25 and BUD5, each of which encodes a guanine nucleotide exchange factor for the ras superfamily gene products. Deletion of the entire MSI2 coding region reveals that MSI2 is not essential but the disruptant shows a cold-sensitive phenotype. Under the non-permissive conditions, more than 70% of the msi2 disruptants arrested at telophase as large budded cells with two nuclei divided completely and elongated spindles, indicating that the msi2 deletion is a cell division cycle mutation. These results suggest that MSI2 is involved in the termination of M phase and that this process is regulated by a ras superfamily gene product.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 72
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 463-474 
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; cell polarity ; cellular morphogenesis ; GTPases ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Cdc24p and Cdc42p are involved in the control of cell polarity during the Saccharomyces cerevisiae cell cycle. Cdc42p is a member of the Ras superfamily of GTPases and Cdc24p displays limited amino-acid sequence similarity with the Dbl proto-oncoprotein, which acts to stimulate guanine-nucleotide exchange on human Cdc42p. We have performed several genetic experiments to test whether Cdc24p and Cdc42p interact within the cell. First, overexpression of Cdc24p suppressed the dominant-negative cdc42D118A allele. Second, overexpression of wild-type CDC24 and CDC42 genes together was a lethal event resulting in a morphological phenotype of large, round, unbudded cells, indicating a loss of cell polarity. Third, a cdc24ts cdc42ts double mutant exhibited a synthetic-lethal phenotype at the semi-permissive temperature of 30°C. These data suggest that Cdc24p and Cdc42p interact within the cell and that Cdc24p may be involved in the regulation of Cdc42p activity.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 73
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 497-508 
    ISSN: 0749-503X
    Keywords: Protein secretion and processing ; gene expression ; killer toxin ; Kex2 protease ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: K1 preprotoxin is the 316 residue precursor of the K1 killer toxin secreted by the yeast Saccharomyces cerevisiae. The SPβla reporter consists of the mature, secreted form of β-lactamase (βla) fused to S and P, two fragments of preprotoxin. S is the N-terminal 34 residues, including the secretion signal. P, a 67 residue ‘processing’ segment with three sites for N-glycosylation, terminates in a Lys Arg site for cleavage by the Kex2 protease. Expression of SPβla in yeast results in efficient secretion, processing by signal peptidase and glycosylation in the endoplasmic reticulum, producing proßla. Kex2 cleavage of proßla in the lumen of a late Golgi compartment releases βla, which accumulates stably in culture media buffered at pH 5·8-7. The half-life of secretion is 11 min at 30°C; 10-12% of the total activity in exponential-phase cells is intracellular, mostly in the form of proßla, indicating that transit from the endoplasmic reticulum to the Golgi is rate limiting. We have used SPβla expression in single- and multi-copy vectors to compare the PGK, GAL1, GAL10, PHO5 and CUP1 promoters under varying nutritional conditions. In exponential-phase cells, secretion of βla over a 40-fold range and up to several μg/ml was proportional to transcript level, demonstrating that SPβla can be employed as a convenient secreted reporter of promoter function in yeast.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 74
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 415-415 
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 75
    ISSN: 0749-503X
    Keywords: Yeast ; fungi ; zymocin ; promoter ; pGKL1 ; pGKL2 ; pSKL ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The toxin-encoding linear plasmid systems found in Pichia acaciae and Kluyveromyces lactis yeasts appear to be quite similar, both in function and structural organization. By Southern hybridization, a linear plasmid of P. acaciae, pPac1-2, was found to hybridize to the second open reading frame (ORF2) of K. lactis plasmid pGKL1, known to encode the α and β subunits of the K. lactis toxin. A 1·7 kbp segment of pPac1-2 DNA was cloned, sequenced and shown to contain four regions of strong homology to four similarly oriented regions of K. lactis ORF2. This 1·7 kbp fragment also contained an ORF of 1473 bp that could encode a protein of ∼ 55·8 kDa. Like the α subunit gene of K. lactis ORF2, a very hydrophobic region occurs at the N-terminus, perhaps representing a signal sequence for transport out of the cell. Unlike K. lactis ORF2, however, the encoded polypeptide is much smaller and lacks a recognizable domain common to chitinases. The structure of a toxin that includes the translation product of this P. acaciae ORF would likely be quite different from that of the K. lactis toxin. Analysis of the upstream region of the P. acaciae ORF revealed an upstream conserved sequence identical to that found before ORFs 8 and 9 of pGKL2. A possible hairpin loop structure, as has been described for each of the four K. lactis pGKL1 ORFs, was found just upstream of the presumed start codon. The similarity of the promoter-like elements found in the linear plasmid genes of these diverse yeasts reinforces the idea of the existence of a unique, but highly conserved, expression system for these novel plasmids. The sequence has been deposited in the GenBank data library under Accession Number U02596.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 76
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 491-496 
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; ARS1 ; DNA replication, mitotic ; DNA replication, premeiotic ; plasmid integration ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have investigated the significance of the chromosomal replication origin, ARS1, during the entire life cycle of yeast. This was done by substituting the chromosomal copy with a series of ars1 deletion mutants. It was shown that the ARS1 replication origin is not essential for mitotic or premeiotic DNA replication since no effect on growth, chromosomal loss rate and spore viability was observed in the ars1 mutant strains. We conclude that replication origins are abundantly, present in the yeast genome and that the removal of a single replication origin is compensated for by replication forks emanating from neighbouring origins.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 77
    ISSN: 0749-503X
    Keywords: Mitochondrial carriers ; duplication ; citrate synthase ; RNA binding ; ribosomes ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A 15·1 kb fragment of the yeast genome was allocated to the centromeric region of chromosome XIV by genetic mapping. It contained six bona fide genes, RPC34, FUN34, CIT1 (Suissa et al., 1984), RLP7, PET8 and MRP7 (Fearon and Mason, 1988) and two large open reading frames, DOM34 and TOM34, RPC34 and RLP7 define strictly essential functions, whereas CIT1, PET8 and MRP7 encode mitochondrial proteins. The PET8 product belongs to a family of mitochondrial carrier proteins. FUN34 encodes a putative transmembraneous protein that is non-essential as judged from the normal growth of the fun34-::L̈K18 (URA3) allele, even on respirable substrates. TOM34 codes for a putative RNA binding protein, and DOM34 defines a hypothetical polypeptide of 35 kDa, with no significant homology to known proteins. The region under study also contains two divergently transcribed tDNAs, separated only by a chimeric transposable element. This tight tDNA linkage pattern is commonly encountered in yeast, and a general hypothesis is proposed for its emergence on the Saccharomyces cerevisiae genome. RPC34, RLP7, PET8 and MRP7 are unique on the yeast genome, but the remaining genes belong to an extant centromeric duplication between chromosome III and XIV. The sequences have been deposited in the EMBL/GenBank data libraries under Accession Numbers L11277, L19167, M11344, M22116, V02536, X00782 and X63746.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 78
    ISSN: 0749-503X
    Keywords: Random-breakage mapping ; yeast ; APN1 ; YUH1 ; chromosome XI ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have used the previously described technique of random-breakage mapping to locate the two yeast genes APN1 and YUH1. The APN1 locus is located ∼235 kb from the left telomere of chromosome XI, and shows weak (∼53 cM) genetic linkage to ura1. The YUH1 locus is located ∼140 kb from the right telomere of chromosome X, and genetically maps 3·6 cM distal to cdc11. In addition, we show by random-breakage mapping that TRP3 is located ∼45 kb from the left telomere of chromosome XI, whereas FAS1 is ∼110 kb from the same telomere. This supports a gene order on the left distal portion of chromosome XI that agrees with other physical reports but is inverted with respect to Edition 11 of the published genetic map. This report confirms that random-breakage mapping is a rapid and convenient method of locating cloned genes.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 79
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 80
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 653-657 
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; basic-amino-acid permease ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A Saccharomyces cerevisiae gene (1722 bp), encoding a protein (574 aa) highly homologous to the basic-amino-acid permeases LYP1 and CAN1, was sequenced. The gene, which was named APL1 (Amino-acid Permase Like), is located 881 bp upstream from LYP1 (lysine-specific permease), and in head-to-head orientation to it. These sequence data have been deposited in the EMBL/GenBank/DDBJ nucleotide sequence data libraries under Accession Number X74069.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 81
    ISSN: 0749-503X
    Keywords: Genome sequencing ; Saccharomyces cerevisiae ; chromosome XI ; catabolic threonine dehydratase ; membrane transporter ; hydantoinase ; phospholipase A2-activating protein ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We report the entire sequence of a 26·4 kb segment of chromosome XI of Saccharomyces cerevisiae. Identification of the known loci URA1, TRP3 and SAC1 revealed a translocation compared to the genetic map. Additionally, six unknown open reading frames have been identified. One of them is similar to catabolic threonine dehydratases. Another one contains characteristic features of membrane transporters. A third one is homologous in half of its length to the prokaryotic hydantoinase HyuA and in the other half to hydatoinase HyuB. A fourth one is homologous to the mammalian phospholipase A2-activating protein. A fifth one, finally, is homologous to the hypothetical open reading frame YCR007C of chromosome III. The sequence has been deposited in the EMBL data library under Accession Number X75951.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 82
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 701-708 
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 83
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. ii 
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 84
    ISSN: 0749-503X
    Keywords: Yeast ; adenylate cyclase ; Ras ; Kluyveromyces marxianus ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The presence of adenylate cyclase activity was first demonstrated in membrane fractions from the budding yeast Kluyveromyces marxianus. The enzyme showed a Mn2+- and Mg2+-dependent activity, with optimal pH at around 6 as observed in other yeast species. As in Saccharomyces cerevisiae, where adenylate cyclase is regulated by RAS1 and RAS2, we detected a guanyl nucleotide-dependent activity. Interestingly Y13-259 monoclonal antibody, raised against mammalian p21Ha-ras, inhibited Mg2+ plus GTP-γ-S-dependent cAMP production, suggesting that the GTP binding proteins involved in adenylate cyclase regulation could be Ras proteins. The same antibody recognized on Western blot and immunoprecipitated a 40 kDa polypeptide from K. marxianus crude membranes. This polypeptide was not detected by an anti-RAS2 polyclonal antibody raised against S. cerevisiae RAS2 protein, suggesting that Ras proteins from the two species could be structurally different.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 85
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 709-717 
    ISSN: 0749-503X
    Keywords: Ribosomal DNA spacers ; oligonucleotide probes ; Candida albicans ; rapid yeast identification ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In order to develop DNA probes for rapid, sensitive and specific detection of the pathogenic yeast species Candida albicans, we carried out comparative sequence analysis of the two internal transcribed spacer regions (ITS1 and ITS2) of the ribosomal DNA (rDNA) units of C. albicans and the closely related pathogenic species C. tropicalis. While overall sequence similarity between the two species was considerable (65-75%), both ITS1 and ITS2 were found to contain distinct regions with sufficient sequence divergence to make them suitable as specific target sites for the identification of C. albicans. On the basis of these results one ITS1-derived (ANAB1) and two ITS2-derived (ANAB2 and ANAB3) oligonucleotides were selected, chemically synthesized, and used as hybridization probes. Their specificity and reliability were evaluated in dot-blot hybridization experiments with total genomic DNA from 13 strains of medically important Candida species, six strains of other yeast genera associated with man and animals, and ten strains previously identified as C. albicans by phenotypic criteria. Under well-defined hybridization conditions the three probes hybridized exclusively with DNA derived from strains belonging to the species C. albicans, thus demonstrating their potential clinical usefulness. The failure of four of the (presumed) C. albicans strains to show hybridization to the ITS probes sheds doubt upon their taxonomic classification, which is reinforced by other phenotypic aspects of these strains.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 86
    ISSN: 0749-503X
    Keywords: Poly(ADP-ribose) polymerase ; fission yeast ; cell cycle ; DNA repair ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The activity of poly(ADP-ribose) polymerase (PADPRP), a chromatin-associated enzyme present in most eukaryotic cells, is stimulated by DNA strand breaks, suggesting a role for the enzyme in the cellular response to DNA damage. However, the primary function of PADPRP remains unknown. We have selected Schizosaccharomyces pombe as a simple eukaryotic system in which to study PADPRP function because this fission yeast shares with mammalian cells important cellular features possibly associated with poly-(ADP-ribos)ylation pathways. We investigated the existence of an endogenous yeast PADPRP by DNA and RNA hybridization to mammalian probes under low-stringency conditions and by PADPRP activity assays. Our data indicate that fission yeasts are naturally devoid of PADPRP. We therefore isolated S. pombe strains expressing PADPRP by transformation with a human full-length PADPRP cDNA under the control of the SV40 early promoter. The human PADPRP construct was transcribed and translated in S. pombe, generating a major transcript of the same size (3.7 kb) as that detected in mammalian cells and a 113-kDa polypeptide, identical in size to the native human PADPRP protein. Yeast recombinant PADPRP was enzymatically active and was recognized by antibodies to human PADPRP. S. pombe cells expressing PADPRP (SPT strains) showed a stable phenotype that was characterized by: (i) cell cycle retardation as a result of a specific delay at the G1 phase, (ii) decreased cell viability in stationary cultures, (iii) enhanced rates of spontaneous and radiation-induced ade6-ade7 mutations, and (iv) increased sensitivity to radiation. SPT strains may prove efficient tools with which to investigate PADPRP functions in eukaryotic cells.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 87
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 1075-1082 
    ISSN: 0749-503X
    Keywords: Schizosaccharomyces pombe ; thiamine ; transcription ; inducible promoter ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We previously described a screen for thiamine-repressible genes in Schizosaccharomyces pombe and reported on one such gene, nmt1, required for thiamine biosynthesis. Here we describe a second gene, nmt2, recovered in the same screen. Disruption of nmt2 also resulted in thiamine auxotrophy, indicating a role for the nmt2 gene product in thiamine biosynthesis. Both genes are highly transcribed in minimal medium and repressed in medium containing thiamine, and nuclear ‘run-on’ experiments confirm that expression in both cases is controlled by the rate of transcription initiation. The virtually identical kinetics of induction and repression suggest that the two genes are co-ordinately regulated. Sequence comparison of the two promoters reveals a canonical TATA box, downstream of which is a perfectly conserved 11 bp element. Transcript mapping experiments show that transcription initiation of both genes is centred on this element.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 88
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; sulphite resistance ; gene cloning and sequencing ; SUL1 ; zinc-finger protein ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: In this paper we describe the cloning and sequencing of the gene (SUL1) responsible for sulphite resistance in a Saccharomyces cerevisiae mutant (Casalone et al., 1992). The deduced amino acid sequence predicted that the gene codes for a zinc-finger protein with five fingers. Comparison of wild-type and mutant gene sequences demonstrated that the mutation event was a transversion from C to G; as a consequence of the mutation a histidine substituted an aspartic acid, affecting directly the fourth finger structure. The SUL1 gene sequence corresponds to that of FZF1 gene (Breitwieser et al., 1993) to which no function was attributed. The sequence has been entered in the EMBL data library under Accession Number 77592.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 89
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 1157-1171 
    ISSN: 0749-503X
    Keywords: rDNA ; ribosomal DNA ; rDNA clusters ; chromosomes ; pulsed-field gel electrophoresis ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Several recent investigations, employing restriction endonucleases that do not cleave within rDNA units, revealed that a number of laboratory strains of Saccharomyces cerevisiae apparently contain a single tandem array of approximately 50 to 200 rDNA units on each chromosome XII homolog. The number of these rDNA units varies from strain to strain, among subclones of the same strain, and after different conditions of growth. In contrast, the commonly-used strain S288C and its derivatives contain two clusters on each chromosome XII homolog. Although the two clusters are stably maintained, the number of rDNA units within each cluster can vary as in strains with single clusters.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 90
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 1211-1216 
    ISSN: 0749-503X
    Keywords: Actin ; cytoskeleton ; SAC2 ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A temperature-sensitive mutation (act1-1) in the essential actin gene of Saccharomyces cerevisiae can be suppressed by mutations in the SAC2 gene. A cloned genomic DNA fragment that complements the cold-sensitive growth phenotype associated with such a suppressor mutation (sac2-1) was sequenced. The fragment contained an open reading frame that encodes a 641 amino acid predicted hydrophilic protein with a molecular weight of 74 445. No sequences with significant similarity to SAC2 were found in the GenBank and EMBL databases. A SAC2 disruption mutation was constructed which had phenotypes similar to the sac2-1 point mutation. A haploid SAC2 disruption strain failed to grow at low temperature and the disruption allele suppressed the temperature-sensitive act1-1 growth defect. The suppression phenotype was dependent on the strain background. The SAC2 sequence has been submitted to the EMBL data library (Accession Number Z29988).
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 91
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; genomic sequencing ; chromosome II ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A 3·2 kb EcoRI fragment of yeast Saccharomyces cerevisiae was entirely sequenced. Two new open reading frames were identified. The first is extremely hydrophobic, and would likely be an integral membrane protein. It has significant similarity to only one reported gene, a gene of unknown function from Drosophila melanogaster. The second ORF is asparagine-rich and very serine-rich, with a remarkable stretch of nearly 26 consecutive asparagine residues comprised of the same codon. It has no significant similarity to any reported gene. The fragment maps to chromosome II on the left arm between the CDC27 and ILS1 loci. The nucleotide sequence reported in this paper has been deposited in the GenBank database with the Accession Number M89908.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 92
    ISSN: 0749-503X
    Keywords: Yeast ; chromosome XIV ; citrate synthase ; FUN34 ; PRP2 ; RPC34 ; SIS1 ; URK1 ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The nucleotide sequence of 23·6 kb of the right arm of chromosome XIV is described, starting from the centromeric region. Both strands were sequenced with an average redundancy of 4·87 per base pair. The overall G+C content is 38·8% (42·5% for putative coding regions versus 29·4% for non-coding regions). Twelve open reading frames (ORFs) greater than 100 amino acids were detected. Codon frequencies of the twelve ORFs agree with codon usage in Saccharomyces cerevisiae and all show the characteristics of low level expressed genes. Five ORFs (N2019, N2029, N2031, N2048 and N2050) are encoded by previously sequenced genes (the mitochondrial citrate synthase gene, FUN34, RPC34, PRP2 and URK1, respectively). ORF N2052 shows the characteristics of a transmembrane protein. Other elements in this region are a tRNAPro gene, a tRNAAsn gene, a τ34 and a truncated δ34 element. Nucleotide sequence comparison results in relocation of the SIS1 gene to the left arm of the chromosome as confirmed by colinearity analysis. The nucleotide sequence data reported in this paper will appear in the EMBL, GenBank and DDBJ Nucleotide Sequence Databases under the accession number X77395.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 93
    ISSN: 0749-503X
    Keywords: Saccharomyces cerevisiae ; yeast ; AAA-protein family ; putative ATPase ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A nuclear gene from Saccharomyces cerevisiae was cloned by genetic complementation of a temperature-sensitive respiratory-deficient mutant. DNA sequence analysis reveals that it encodes a protein with homology to Yme1, FtsH and Tma, proteins which belong to the AAA-protein family (ÃPases associated with diverse cellular activities). The members of this family are involved in very different biological processes. Yme1p, a yeast mitochondrial protein, affects the rate of DNA escape from mitochondria to the nucleus and the Escherichia coli FtsH protein is apparently involved in the post-translational processing of PBP3, a protein necessary for septation during cell division. This newly sequenced gene, which we have designated AFG3 for ÃPase family gene 3, encodes a putative mitochondrial protein of 760 amino acid residues that is closely related to FtsH, Tma (protein from Lactococcus lactis) and Yme1p with 58, 55 and 46% identity respectively. The sequence has been deposited in the EMBL data library under Accession Number X76643.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 94
    ISSN: 0749-503X
    Keywords: Firefly luciferase ; yeast expression ; gene reporter ; Saccharomyces cerevisiae ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The LUC gene coding for Photinus pyralis firefly luciferase was cloned in different yeast episomal plasmids in order to assess its possibilities as an in vivo reporter gene. Activity of the enzyme in transformed cells in vivo was measured by following light emission and assay conditions optimized in intact cells, with regard to oxygen concentration, temperature, cell concentration in assay mixtures and external ATP concentration. Among the factors tested, light emission was drastically influenced by the external pH in the assay (which resulted in a ten-fold amplification signal) and by substrate permeability. The growth phase of the cells was also important for the level of activity detected. Cloning of firefly luciferase gene under the control of different yeast-regulated promoters (ADH1, GAL1-10) enabled us to measure their strength which correlated well with previously described data. We conclude that firefly luciferase is an adequate gene reporter for the in vivo sensitive determination of gene expression and promoter strength in yeast.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 95
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 1395-1402 
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 96
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 1403-1413 
    ISSN: 0749-503X
    Keywords: Chromosome XI of Saccharomyces cerevisiae ; transcript map ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A detailed and systematic transcript map is a first and necessary step to characterize new genes revealed by systematic sequencing. Chromosome XI of Saccharomyces cerevisiae contains 331 open reading frames (ORFs) of which 44% are of unknown function (Dujon et al., 1994). As a first study towards complete transcript analysis of chromosome XI, we have extracted RNA from three isogenic strains (a, α and 2 n) grown in three standard laboratory media, and have analysed them using contiguous probes covering two regions of 17 and 19 kilobases, respectively. All 20 predicted ORFs in the sequences correspond to expressed genes, six of which have no predicted function. Four short ORFs which were suspected as not being real genes on the basis of their sequence are not expressed in our growth conditions. An additional transcript which does not correspond to a large ORF was found. Steady-state RNA level of most ORFs is 10 to 100 times than that of the actin gene, only three are transcribed in comparable amounts. Three ORFs show variable levels of transcripts in the different growth conditions, all patterns being different from one another. Extrapolation of these results to systematic transcript analysis of chromosome XI and other yeast chromosomes is presented.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 97
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994), S. 1459-1466 
    ISSN: 0749-503X
    Keywords: Pichia pinus ; glucose catabolite repression ; glucose transport ; isolation of mutants ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A new method for the isolation of glucose repression-insensitive mutants in the methylotrophic yeast Pichia pinus was developed. The method is based on screening of small suspension samples derived from 2-deoxyglucose-resistant colonies for alcohol oxidase activity. Alcohol oxidase activity was evaluated by determination of formaldehyde excreted by cells. Mutants with glucose non-repressible alcohol oxidase and catalase synthesis were obtained. All mutants grew poorly on D-xylose compared to the wild type, whereas growth on L-arabinose was similar to the wild type. Changes in the glucose transport system were suggested to be responsible for altered growth characteristics and defective glucose repression.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 98
    ISSN: 0749-503X
    Keywords: Candida tropicalis ; peroxisomes ; nonspecific lipid-transfer protein ; sterol carrier protein-2 ; stress protein ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: A 14-kDa peroxisomal-matrix protein, named PXP-18, of the yeast Candida tropicalis is a structural and functional homologue of the mammalian nonspecific lipid-transfer protein (identical to sterol carrier protein-2). PXP-18 protected acyl-coenzyme A oxidase (ACO), the rate limiting enzyme of the peroxisomal β-oxidation of fatty acids, from thermal inactivation at 48°C or 70°C. This effect was dose-dependent and not replaceable either by chicken egg white lysozyme, which is similar to PXP-18 (insofar as it is basic, small, and monomeric), or by bovine serum albumin, a carrier of lipids in the blood. ACO was irreversibly denatured by heat treatment at 70°C for 15 min. However, when ACO and PXP-18 were similarly heat-treated, they formed a large complex at a molar ratio of PXP-18 to ACO subunit that was about one, independent of their initial ratio. This near-stoichiometric complex had ACO activity after a 500-fold dilution and was accompanied by ACO that was free of PXP-18 and indistinguishable from native ACO in size and activity. PXP-18 also protected urate oxidase, another peroxisomal enzyme, from inactivation at 66°C for 15 min and facilitated the renaturation of ACO denatured by 2 M urea. These results indicated that PXP-18 is active in modulating the structure of peroxisomal enzymes in vitro. It is possible that PXP-18 functions as a stress protein or as a part of the system that keeps peroxisomal proteins intact.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 99
    ISSN: 0749-503X
    Keywords: Yeast ; genome ; ribosomal protein S13 ; SUP46 ; URP1 ; rat ribosomal protein L21 ; AAA-family proteins ; MADS-domain ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: The nucleotide sequence of a 12·5 kb fragment localized to the right arm of chromosome II of Saccharomyces cerevisiae has been determined. The sequence contains eight putative genes. Two of them are contiguous and represent two ribosomal protein genes: SUP46 and URP1. SUP46 is implicated in translation fidelity and encodes the ribosomal protein S13. URP1 is homologous to the rat ribosomal protein gene L21. The open reading frame (ORF) YBR1245 is similar in its N-terminal part to transcription factors like SRF and MCM1. The ORF YBR1308 shows homology with proteins of the AAA-family (ATPases Associated with diverse cellular Activities). Two genes are predicted to encode putative membrane proteins. The sequence has been deposited in the EMBL data library under Accession Number U02073.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 100
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Yeast 10 (1994) 
    ISSN: 0749-503X
    Keywords: Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...