Involvement of cAMP and calmodulin in endocytic yolk uptake during Xenopus laevis oogenesis

LUQUE, M.E.; SERRANO, M.A.; MÓNACO, M.E.; VILLECCO, E.I.; SÁNCHEZ, S.S.

ZYGOTE

CAMBRIDGE UNIV PRESS

Año: 2011 p. 1 - 9

0967-1994

The aim of the present study was to show the participation and physiological role of CaM and cAMP during vitellogenin endocytic uptake in the amphibian Xenopus laevis. The results showed a differential distribution of CaM in the ovary follicles during oogenesis. The CaM intracellular localization was not affected by gap junction’s downregulation and CaM inhibition did not completely abolished the endocytic activity of oocytes. We showed that the cAMP was able to completely rescue the endocytic competence in follicles in which gap junctional communication had been disrupted by octanol. Moreover cAMP was capable of restoring oocyte endocytic capability in the presence of octanol and Stelazine, a CaM inhibitor. We propose that, in Vtg uptake regulation, cAMP is upstream to CaM during the endocytic signalling pathway.