Linked Life Data

11526117

Source:http://linkedlifedata.com/resource/pubmed/id/11526117

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
44
pubmed:dateCreated
2001-10-29
pubmed:abstractText
Zonadhesin is a mosaic protein in sperm membrane fractions that binds directly and in a species-specific manner to the extracellular matrix (zona pellucida) of the oocyte. The active form of pig zonadhesin from capacitated, epididymal spermatozoa comprises two covalently associated polypeptide chains of M(r) 105,000 (p105) and M(r) 45,000 (p45). Here we report detection and characterization of multiple zonadhesin isoforms in freshly ejaculated cells. Antibodies to the predicted von Willebrand D0-D1, D1, and D3 domains of pig zonadhesin recognized p105, p45, and additional M(r) 60,000-90,000 polypeptides in particulate fractions of uncapacitated cells. Although the p105/45 form constituted a minority of all zonadhesin forms in sperm membrane fractions, it was the predominant form capable of binding to the pig zona pellucida. Zonadhesin-binding sites were distributed over the entire zona pellucida. Anion exchange chromatography resolved active, p105/45 zonadhesin from the p60-90 inactive forms. Without disulfide bond reduction some zonadhesin was M(r) > or = 300,000, including M(r) 300,000 and 900,000 proteins comprising in part multimers of p105/45. The multimeric forms did not bind the zona pellucida as avidly as did the p105/45 monomer. Expressed D1 and D3 domain fragments containing the CG(L/V)CG sequence motif spontaneously formed multimers at -246 mV E(h) in vitro. Double Cys --> Ser mutants of the D1 fragment formed multimers with the same apparent kinetics as the wild type protein. Zonadhesin localized to the apical head of pig spermatozoa. We conclude that a heterogeneous combination of specific proteolysis and intermolecular disulfide bond formation in the sperm head generates multiple forms of zonadhesin with differing avidities for the zona pellucida.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
2
pubmed:volume
276
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
41502-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Heterogeneous processing and zona pellucida binding activity of pig zonadhesin.
pubmed:affiliation
Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't