Valosine containing protein is a substrate of cAMP-activated boar sperm tyrosine kinase.

Previously we reported that treatment of boar sperm with cAMP-elevating drugs induces tyrosine phosphorylation of a triton-insoluble 93 kDa protein (p93). We have isolated p93 by preparative SDS electrophoresis and blotting from urea-extracted boar sperm and identified it as a valosine containing protein (VCP) by mass spectrometry and microsequencing. With the use of antibodies to VCP and phosphotyrosine (pY) we found that both p93 and VCP are poorly extractable with triton and are solubilized in > 6 M urea.

Accumulation of the proteolytic marker peptide ubiquitin in the trophoblast of mammalian blastocysts.

Ubiquitination is a universal protein degradation pathway in which the molecules of 8.5-kDa proteolytic peptide ubiquitin are covalently attached to the epsilon-amino group of the substrate's lysine residues. Little is known about the importance of this highly conserved mechanism for protein recycling in mammalian gametogenesis and fertilization.

Monoclonal antibodies to intra-acrosomal proteins inhibit gamete binding in vitro.

The sperm-zona pellucida-binding assay in vitro was used as a functional test for zona pellucida-binding ability of boar spermatozoa after co-incubation with monoclonal antibodies against intra-acrosomal proteins. The effect of monoclonal antibodies ACR.2 against boar acrosin (55, 53, 45 and 38 kDa), and Hs-8 against boar intra-acrosomal protein (230, 110, 88, 60, 48 kDa) on boar spermatozoa-porcine oocyte binding was examined.

[Use of human sperm protein monoclonal antibodies in the diagnosis of sperm pathology and selection of a suitable assisted reproduction method for fertilization].

Objective: Use of monoclonal antibodies against sperm proteins in human medicine.

Design: Experimental and clinical studies.

Setting: Dep.