EXPRESSION AND LOCALIZATION OF COMPLEXIN IN MOUSE EGGS

BELLO, OSCAR D; ZANETTI, MARÍA N.; RODRÍGUEZ, FACUNDO; CAPPA, ANDREA I. ; MAYORGA, LUIS S.; MICHAUT, MARCELA A.

San Luis

Congreso; XLVII Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2011

Argentine Society for Biochemistry and Molecular Biology

Cortical granule exocytosis is one of the most important steps, which occurs after sperm-egg fusion, at fertilization. Cortical granule exocytosis is induced by the spermatozoon and blocks polyspermy to enable a successful embryonic development. Induction of cortical granule exocytosis depends on intracellular calcium mobilization in the egg; however little is known about the signal transduction pathway downstream of calcium mobilization. Our general aim is to identify the proteins involved in cortical granule exocytosis, analyze their functions, and arrange them in a working model. We hypothesized that cortical granule exocytosis is controlled by a conserved protein machinery that involves SNAREs, Rabs, and additional proteins that are key for calciumregulated exocytosis, such as complexin. The aim of this work was to investigate the expression and localization of complexin in mouse eggs. U sing an antibody that recognizes two isoforms of complexin, Western blots results demonstrated that complexin is expressed in mouse eggs. Immunofluorescence studies showed that complexin localized specifically at the cortical region of mouse eggs, which is enriched in cortical granules. Our results suggest that complexin might be involved in cortical granule exocytosis. H owever, further studies are necessary to identify the specific isoform/s of complexin expressed in mouse eggs.