Related Experiment Video
Updated: Jun 2, 2026

Imaging Calcium in Drosophila at Egg Activation
Published on: August 6, 2016
Involvement of cAMP and calmodulin in endocytic yolk uptake during Xenopus laevis oogenesis
Melchor Emilio Luque1, María de los Angeles Serrano, María Eugenia Mónaco
1Instituto Superior de Investigaciones Biológicas (CONICET), Universidad Nacional de Tucumán, Departamento de Biología del Desarrollo, San Miguel de Tucumán, Argentina.
Abstract:
The aim of the present study was to show the participation and physiological role of calmodulin (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 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 of CaM during the endocytic signalling pathway.
Related Concept Videos
Calmodulin-dependent Signaling
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
Feedback Regulation of Calcium Concentration
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Overview of Secretory Vesicles
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
Fertilization

