Bibliothek

Sie haben 0 gespeicherte Treffer.
Markieren Sie die Treffer und klicken Sie auf "Zur Merkliste hinzufügen", um sie in dieser Liste zu speichern.
feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • 1995-1999  (3)
  • 1985-1989  (4)
  • Life and Medical Sciences  (2)
  • Picea  (2)
  • DNA packaging
  • Primate evolution
  • Shoot population
Materialart
Erscheinungszeitraum
Jahr
Schlagwörter
  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Journal of molecular evolution 28 (1989), S. 212-219 
    ISSN: 1432-1432
    Schlagwort(e): Primate evolution ; Tandem repeats ; Restriction fragment length polymorphisms
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The clone designated hMF #1 represents a clustered DNA family, located on chromosome 1, consisting of tandem arrays displaying a monomeric length of 40 bp and a repetition frequency of approximately 7×103 copies per haploid genome. The sequence hMF #1 reveals multiple restriction fragment length polymorphisms (RFLPs) when human genomic DNA is digested with a variety of 4–6-bp recognition sequence restriction enzymes (i.e., Taq I, Eco RI, Pst I, etc.). When hamster and mouse genomic DNA was digested and analyzed, no cross-species homology could be observed. Further investigation revealed considerable hybridization in the higher primates (chimpanzee, gorilla, and orangutan) as well as some monkey species. The evolutionary relationship of this repetitive DNA sequence, found in humans, to that of other primates was explored using two hybridization methods: DNA dot blot to establish copy number and Southern DNA analysis to examine the complexity of the RFLPs. Homology to the hMF #1 sequence was found throughout the suborder Anthropoidea in 14 ape and New and Old World monkey species. However the sequence was absent in one species of the suborder Prosimii. Several discrepancies between “established” evolutionary relationships and those predicted by hMF #1 exist, which suggests that repetitive elements of this type are not reliable indicators of phylogenetic branching patterns. The phenomenon of marked diversity between sequence homologies and copy numbers of dispersed repetitive DNA of closely related species has been observed inDrosophila mice,Galago, and higher primates. We report here a similar phenomenon for a clustered repeat that may have originated at an early stage of primate evolution.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Planta 199 (1996), S. 459-466 
    ISSN: 1432-2048
    Schlagwort(e): Abscisic acid ; Embryo abundant gene ; Gene expression ; Polyethylene glycol ; Picea ; Somatic embryogenesis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Embryogenic tissues of white spruce [Picea glauca (Moench) Voss] remain in an early developmental stage while cultured on 2,4-dichlorophenoxyacetic acid and N6-benzyladenine, but develop to cotyledonary embryos when these phytohormones are replaced by abscisic acid. Twenty-eight cDNAs were isolated from cotyledonary embryos by differential screening against immature embryo and non-embryonic tissues. Temporal expression patterns of these cDNAs during ABA-stimulated somatic embryo development were observed. This showed that clones could be allocated to various groups, including embryo-abundant, embryo-maturation-induced, and those whose expression was modulated during embryo development, germination or in non-embryogenic tissues. Expression corresponding to these cDNA clones showed that there were various responses to exogenous ABA or polyethylene glycol during a period of 48 h. Analyses of DNA and predicted amino acid sequence revealed that 12 of 28 cDNA clones had no known homologues, while others were predicted to encode different late-embryogenesis-abundant proteins, early methionine-labelled proteins, storage proteins, heat-shock proteins, glycine-rich cell wall protein, metallothionein-like protein and some other metabolic enzymes.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    ISSN: 1432-2048
    Schlagwort(e): Abscisic acid ; Somatic embryogenesis ; Gene expression ; Heat shock protein ; Picea ; Polyethylene glycol
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Three cDNAs (PgEMB22, 27 and 29) predicted to encode low-molecular-weight (LMW) heat-shock proteins (HSPs) were cloned and characterized from white spruce [Picea glauca (Moench) Voss] somatic embryo tissues by differentially screening a cotyledonary embryo cDNA library. Clone PgEMB22 is predicted to encode a putative mitochondria-localized LMW HSP, and PgEMB27 and 29 are predicted to encode different cytoplasmic class II LMW HSPs, although they share 84.7% identity within DNA coding regions and 83.0% identity for predicted proteins. They are developmentally regulated during somatic embryo development and subsequent embryo germination, in addition they show strong response to heat-shock stress. Transcripts of the two kinds of hsp genes could be detected in embryogenic tissues before induction of embryo maturation, but subsequently increased, being most abundant at late embryo stages. Gene expression levels were very low or not detectable in germinated plantlets or needle tissues from older plants. Abscisic acid and polyethylene glycol, stimulators for spruce embryo maturation, could also induce the hsp genes.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    ISSN: 1617-4623
    Schlagwort(e): cos ; DNA gyrase ; DNA packaging ; Integration host factor ; Terminase
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary A mutant of λ was isolated that grows in the Escherichia coli himAΔ/gyrB-him320(Ts) double mutant at 42°C; conditions which are non-permissive for wild-type λ growth. The responsible mutation, ohm1, alters the 40th codon of the Nul reading frame. The Nul and A gene products comprise the terminase protein which cleaves concatameric DNA into unit-length phage genomes during DNA packaging. The Nul-ohm1 gene product acts in trans to support λ growth in the double himA/gyrB mutant, and λcos154 growth in the single himA mutant. The observation that an alteration in Nul suppresses the inhibition of growth in the double himA/gyrB mutant implicates DNA gyrase, as well as integration host factor, in the DNA: protein interactions that occur at the initiation of packaging.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 3 (1985), S. 55-60 
    ISSN: 1573-5044
    Schlagwort(e): Shoot population ; apple shoot cultures ; shoot quality ; micropropagation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract The quality of shoots in cultures of the apple rootstock, M4, was used as a criterion for the selection of an optimum medium. The frequency of shoots in defined shoot clases was monitored for each of five media, which differed in the type and concentration of phytohormone. Media containing BA (1.15 mg l-1) and IBA (either 0.15 or 0.20 mg l-1) produced the maximum number of shoots that were desirable for transplantation and acclimatization.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 6
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Cellular Physiology 135 (1988), S. 145-150 
    ISSN: 0021-9541
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Short-term hyperthermic episodes (in vivo and in vitro) alter gene expression in mammalian lymphocytes, resulting in the enhanced synthesis of a select group of polypeptides - the heat-shock proteins - and the depressed synthesis of many normally synthesized polypeptides. Such alterations could have profound implications to an individual if the appropriate functioning of lymphocytes within the immune response was compromised by a depression in immunoglobulin synthesis during naturally occurring periods of hyperthermia, such as fever. In the present study we asked if heat-shock affects the facultative synthesis and secretion of immunoglobulin G by cultured mouse lymphocytes. We found that the quantity of immunoglobulin G synthesized and secreted by these cells is not affected by heat-shock treatments sufficient to induce the synthesis of heat-shock proteins.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 7
    Digitale Medien
    Digitale Medien
    New York, NY : Wiley-Blackwell
    BioEssays 18 (1996), S. 919-923 
    ISSN: 0265-9247
    Schlagwort(e): Life and Medical Sciences ; Cell & Developmental Biology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Medizin
    Notizen: Expression of transgenes in mice, when examined with assays that can distinguish individual cells, is often found to be heterocellular, or variegated. Line-to-line variations in expression of a transgene may be due largely to differences in the proportion of cells in which it is expressed. Variegated silencing by centromeric heterochromatin is well described, but other factors may also affect transgene silencing in mice. Tandem arrays of transgenes themselves form heterochromatin, and some cell lineages may tend to silence transgenes because of extensive facultative heterochromatin in their nuclei. The cis-acting transcriptional control elements within a transgene inhibit silencing, and strainspecific differences in chromatin proteins may strongly influence the extent of variegation. The accessibility of multiple differentiated cell lineages in mice suggests that they may provide a tool for dissecting the role of chromatin-mediated silencing in cell differentiation and tissue-specific gene expression.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...