Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Key words: Yeast — Slippage — Amino acid tandem repeats — Homopeptides — Protein function — Genome analysis — Codon composition  (1)
  • freeze-thawing  (1)
  • isozymes  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Amino Acid Reiterations in Yeast Are Overrepresented in Particular Classes of Proteins and Show Evidence of a Slippage-Like Mutational Process (1999)
    Springer
    Journal of molecular evolution 49 (1999), S. 789-797 
    Details
    ISSN: 1432-1432
    Keywords: Key words: Yeast — Slippage — Amino acid tandem repeats — Homopeptides — Protein function — Genome analysis — Codon composition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract. Long amino acid repeats are often observed in eukaryotic proteins. In humans, several neurological disorders are caused by proteins containing abnormally long polyglutamines. However, no systematic analysis has attempted to investigate the relationship between reiterations of particular amino acids and protein function, the possible mechanisms involved in the generation of these regions, or the contribution of selection in restricting their genomic distribution, in a large collection of wild-type proteins. We have used baker's yeast open reading frames to study these questions. The most abundant amino acid repeats found in yeast proteins are repeats of glutamine, asparagine, aspartic acid, glutamic acid, and serine. Different amino acid repeats are concentrated in different classes of proteins. Acidic and polar amino acid repeats are significantly associated with transcription factors and protein kinases, while serine repeats are significantly associated with membrane transporter proteins. In most cases the codon structures encoding the repeats at the gene level show a significant bias toward long tracts of one of the possible codons, suggesting that trinucleotide slippage has played an important role in generating these reiterations. However, many, particularly those encoding serine repeats, do not show evidence of slippage. The distributions of codon repeats within proteins and between coding and noncoding regions of the genome, and of amino acids between proteins with different functions, suggest that repeats of these kinds are subject to strong selection.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00006601
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Synaptic Membrane Freezing Affects Modulatory Sites in Avian Central Nervous System GABAA Receptor (1999)
    Springer
    Neurochemical research 24 (1999), S. 1347-1355 
    Details
    ISSN: 1573-6903
    Keywords: GABAA receptor ; barbiturates ; neurosteroids ; freeze-thawing ; chick optic lobe ; endogenous factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Studies were carried out to determine whether barbiturates and neurosteroids share common recognition sites at the GABAA receptor complex in avian CNS. To achieve this, differentially prepared fresh and frozen synaptic membranes were used. Both the barbiturate, pentobarbital, and the neurosteroid, 3α-hydroxy-5α-pregnan-20-one, were able to stimulate GABA binding in both types of membranes. Stimulation differed markedly when both drugs were added jointly to different treated tissue. In frozen membranes drugs acted synergistically and were differentially displaced by picrotoxinin, while in fresh ones, where both compounds were inhibited by the convulsant, this additivity was absent. Post-freezing wash supernatants were collected and used as a source of putative endogenous factors involved in the above mentioned membrane differences. Addition of a high molecular weight fraction from supernatants to frozen synaptic membranes led to an inhibition of barbiturate and neurosteroid potentiation, as well as a loss of their additive effect. Our results indicate that GABAA receptor modulation by barbiturates and neurosteroids is affected by synaptic membrane treatment, with a common modulatory site in fresh membranes and separate recognition sites after a freeze-thawing procedure. There may also be endogenous factors involved in overlapping of modulatory sites, which would thus regulate GABAA receptor functionality by direct interaction with the complex.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1022520320556
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Morphological and isozyme characterisation of Arachis pintoi Krap. et Greg. nom. nud. germplasm (1993)
    Springer
    Euphytica 70 (1993), S. 43-52 
    Details
    ISSN: 1573-5060
    Keywords: Arachis pintoi ; genetic resources ; germplasm characterisation ; groundnut ; isozymes ; PAGE electrophoresis ; tropical forage legume
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Arachis pintoi, a wild perennial relative of the peanut, originated in Brazil, is of increasing importance to pasture improvement in the tropics. Its available genetic base, however, is very narrow, and intensive collection is being carried out. This study aimed to characterise the existing eight accessions in the CIAT germplasm collection in order to describe the existing variation, identify plant types, and discover possible duplicates. Morphological characterisation, based on 60 morphological descriptors, demonstrated that variation exists. Numerical taxonomic techniques were used to rank the importance of these descriptors. Cluster analysis, conducted on those pre-selected morphological characters, grouped the accessions into two major plant types: one homogenous, and the other falling into four distinct subgroups. Polyacrylamide gel electrophoresis (PAGE) was applied to root-tip tissue. Isozyme characterisation by PAGE showed polymorphisms in the isozymes α-EST, ACP, GOT, and DIA. When analysed together, the four isozymes could uniquely distinguish every accession of A. pintoi held in the CIAT germplasm collection. Correspondence and cluster analyses of these isozyme patterns showed the morphologically homogenous plant type to be heterogenous, and the heterogenous morphotype to have similar banding patterns. The lack of continuous patterns of variation in both morphology and isozymes manifests the need for further germplasm collection of A. pintoi.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00029639
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...