Surface localization of the sea urchin egg receptor for sperm.
Surface localization of the sea urchin egg receptor for sperm.
复制标题
海胆卵子精子受体的表面定位。
DOI：
10.1006/dbio.1997.8507
复制
发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Foltz,KR
中科院分区：
文献类型：
--
作者：
Giusti,AF;Hoang,KM;Foltz,KR
The sea urchin egg receptor for sperm is thought to be involved in species-specific sperm–egg interactions at the egg surface. Recent revisions in the deduced amino acid sequence of the cloned cDNAs indicate that the protein encoded does not possess the common structural hallmarks of a membrane protein. Thus, investigation of the localization and association of the protein with the egg surface is crucial. We describe and characterize a new monoclonal antibody raised against recombinant sperm receptor protein. This antibody, in conjunction with several polyclonal antibodies, was used to study the receptor protein in eggs. Immunoprecipitation studies indicated that the antibodies recognize the highMr(ca. 350 K) sperm receptor protein which copurified with egg plasma membrane–vitelline layer complexes. The sperm receptor protein was solubilized only by detergents and not by treatments designed to solubilize peripherally associated or lipid-anchored membrane proteins, suggesting a tight association with the membrane fraction. Confocal immunofluorescence microscopy of live eggs indicated surface staining. Finally, lysylendoproteinase C treatment of live eggs resulted in a loss of the highMrreceptor protein epitopes, and the concomitant release of a 70-kDa proteolytic fragment, which correlated with a reduced ability of the eggs to be fertilized. Taken together, these data indicate that at least some fraction of the sperm receptor protein is present on the egg surface, a requisite locale for a sperm binding protein.
