PARTICIPATION OF ZINC IN THE ASSOCIATION OF CRISP1 TO RAT SPERM DURING EPIDIDYMAL MATURATION

VASEN G; MALDERA JA; WEIGEL MUÑOZ M; COHEN DJ; CUASNICÚ PS

Buenos Aires

Jornada; XII Jornadas Multidisciplinarias de la Sociedad Argentina de Biología (SAB); 2010

Sociedad Argentina de Biología (SAB)

PARTICIPATION OF ZINC IN THE ASSOCIATION OFCRISP1 TO RAT SPERM DURING EPIDIDYMAL MATURATIONVasen G, Maldera JA, Weigel Muñoz M, Cohen DJ, Cuasnicú PS.IByME, CONICET, Buenos Aires, Argentina.E-mail: vasen@dna.uba.arPrevious results from our laboratory indicated the participation ofZinc (Zn2+) in the association of epididymal CRISP1 with the spermsurface during maturation. Based on this observation, the aim ofthe present work has been to investigate the molecular mechanismby which Zn2+ is involved in this process. Flow cytometry assaysusing biotinylated CRISP1 confirmed the requirement of the cationfor the binding of the protein to epididymal caput sperm. Posteriorlocalization studies by fluorescent microscopy revealed theassociation of CRISP1 with the flagellum of caput sperm and toboth the head and tail of caudal cells. While the analysis of thetryptophan fluorescence spectrum did not show conformationalchanges in CRISP1 after its exposure to Zn2+, native gel electrophoresisrevealed the formation of high molecular complexes inducedby the incubation of the protein with the cation. These complexeswere also detected in epididymal luminal fluid and wereabsent when the samples were pretreated with EDTA. Altogether,these results support the participation of a molecular complexformed by CRISP1 and Zn2+ in the association of the