SPERM MOTILITY IN ANURA CORRELATES WITH PKC DEPENDENT ATP-SYNTHASE PHOSPHORYLATION AND ACTIVATION OF CALCINEURIN

MAIDAGAN, PM; O´BRIEN ED; MORALES ES; KRAPF D Y ARRANZ SE

Chascomús

Congreso; XV ANNUAL MEETING OF THE ARGENTINE BIOLOGY SOCIETY (XV JORNADAS ANUALES DE LA SOCIEDAD ARGENTINA DE BIOLOGÍA); 2013

Sociedad Argentina de Biología

SPERM MOTILITY IN ANURA CORRELATES WITH PKC DEPENDENT ATP-SYNTHASE PHOSPHORYLATION AND ACTIVATION OF CALCINEURIN Maidagan P, Morales E, O?Brien E, Visconti P E, Krapf D, Arranz S. Área Biología, Fac Bioquímica y Farmacia, UNR. IBR (CONICET-UNR) E-mail: pmaidagan@fbioyf.unr.edu.ar An exposure of Amphibian sperm to low osmolarity solutions triggers its motility. This process is associated to phosphorylation events by PKA. We have recently identified a phosphorylation/dephosphorylation PCK dependent pathway, also associated with sperm motility and regulated by Calcineurin. The purpose of this study was to advance on the characterization of this pathway and its connection with the PKA dependent one. We observed phosphorylation of ATP-synthase enzyme during the hipoosmotic shock in correlation to a decrease of cellular ATP levels. Simultaneously, we detected dephosphorylation of PKC substrates in the tail region. Pharmacological assays with Ciclosporin-A enabled as to show that dephosphorylation is mediated by calcineurin and its inhibition impaires motility. Our results indicate that both, dephosphorylation of PKC substrates in the flagellum and phosphorylation of ATP-synthase, are necessary events for the activation of the sperm motility in Rhinella arenarum.