Linked Life Data

952894

Source:http://linkedlifedata.com/resource/pubmed/id/952894

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1976-10-20
pubmed:abstractText
Cysteine-rich protamines (Arg = 47-61%, Cys = 8-16%) were isolated from the sperm of an individual guinea pig, human and rabbit and from pooled samples of mouse and rat sperm. Appreciable concentrations of histones were not found in the sperm nuclei of these species. In addition to the protamines, a substance of relatively low molecular weight, which reacted with the Lowry reagent, appeared in crude acid-soluble extracts of sperm nucleoprotein. This unidentified contaminent was resolved from the protamines by chromatography on Bio-Rex 70. Heterogeneity of human and mouse protamines was revealed by electrophoresis at pH 2.7, in the presence of 2.5 M urea, and confirmed by amino acid analysis, which also suggested the presence of 2 or more species of protamine in the rabbit. By contrast, the guinea pig and rat preparations displayed nearly stoichiometric ratios of amino acid residues, approaching homogeneity by this criterion. The functional consequences of crosslinks between cysteine residues of these proteins and the possible species-specific significance of their differing percentages of histidine are discussed. Potentially analogous functions are suggested for phosphorylated serine and threonine, and for ionized cysteine and tyrosine, within the protamines of developing spermatids. Their amino acid compositions indicate that the protamines of eutherian mammals are coded by a C.G-rich genome which has been unusually susceptible to genetic drift. An especially high rate of G leads to A transitions seems to have occurred in the human protamine genes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
434
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
377-89
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1976
pubmed:articleTitle
Comparative analysis of the nuclear basic proteins in rat, human, guinea pig, mouse and rabbit spermatozoa.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.