Sphingosine 1-phosphate and sphingosine kinase are involved in a novel signaling pathway leading to acrosomal exocytosis.

ABSTRACT: Regulated secretion is a central issue for the specific function of many cells; for instance, mammalian sperm acrosomal exocytosis is essential for egg fertilization. Sphingosine 1-phosphate is a bioactive sphingolipid that regulates crucial physiological processes. Here we report that this lipid triggers acrosomal exocytosis in human sperm by a mechanism involving a G(i)-coupled receptor. Real-time imaging showed a remarkable increase of cytosolic calcium upon activation with sphingosine 1-phosphate and pharmacological experiments indicate that the process requires extracellular calcium influx through voltage and store-operated calcium channels and efflux from intracellular stores through inositol 1,4,5-trisphosphate-sensitive calcium channels. Sphingosine 1-phosphate-induced exocytosis r

SUBMITTER: Suhaiman L 

PROVIDER: S-EPMC2871498 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature