Presencia de una proteína epididimaria de rata (DE) en espermatozoides de ratón y su participación en la fertilización cruzada entre ambas especies.

D.COHEN, M.URRUTIA, P.CUASNICÚ.

Mar del Plata, Argentina.

Conferencia; XL Reunión Científica de la Sociedad Argentina de Investigación Clínica (SAIC).; 1995

Rat epididymal protein DE mediates gamete fusion through complementary sites localized on the egg surface. To investigate whether these egg components are involved in the development of rat oolemma fusibility, both the presence of DE-binding components and the ability of the oolemma to fuse with sperm during oogenesis were examined. Localization of DE-complementary sites by indirect immunofluorescence revealed the absence of fluorescent labeling on growing oocytes with a diameter < 50 microns, and the presence of a uniform staining over the entire surface of germinal vesicle oocytes with a diameter > 50 microns. This localization of oolemma components changed progressively to a patchy distribution during maturation. Whereas sperm incorporation was observed only in maturing oocytes, the development of the Hoechst transfer technique to evaluate membrane fusion revealed that germinal vesicle oocytes with a diameter > 50 microns were already competent to fuse with sperm.