Linked Life Data

9177349

Source:http://linkedlifedata.com/resource/pubmed/id/9177349

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6633
pubmed:dateCreated
1997-6-23
pubmed:abstractText
The proper folding of newly synthesized membrane proteins in the endoplasmic reticulum (ER) is required for the formation of functional mature proteins. Calnexin is a ubiquitous ER chaperone that plays a major role in quality control by retaining incompletely folded or misfolded proteins. In contrast to other known chaperones such as heat-shock proteins, BiP and calreticulin, calnexin is an integral membrane protein. Calmegin is a testis-specific ER protein that is homologous to calnexin. Here we show that calmegin binds to nascent polypeptides during spermatogenesis, and have analysed its physiological function by targeted disruption of its gene. Homozygous-null male mice are nearly sterile even though spermatogenesis is morphologically normal and mating is normal. In vitro, sperm from homozygous-null males do not adhere to the egg extracellular matrix (zona pellucida), and this defect may explain the observed infertility. These results suggest that calmegin functions as a chaperone for one or more sperm surface proteins that mediate the interactions between sperm and egg. The defective zona pellucida-adhesion phenotype of sperm from calmegin-deficient mice is reminiscent of certain cases of unexplained infertility in human males.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0028-0836
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
387
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
607-11
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
The putative chaperone calmegin is required for sperm fertility.
pubmed:affiliation
Research Institute for Microbial Diseases, Osaka University, Suita, Japan.
pubmed:publicationType
Journal Article