Serum- and glucocorticoid-Inducible kinase SGK1 regulates reorganization of actin cytoskeleton in mast cells upon degranulation

摘要

Aggregation of the high-affinity IgE receptor (FceRI) on mast cells (MCs) causes MC degranulation, a process that involves cortical F-actin disassembly. Actin depolymerization may be triggered by increase of cytosolic Ca2+. Entry of Ca2+ through the Ca2+ release-activated Ca2+ (CRAC) channels is under powerful regulation by the serum- and glucocorticoid-inducible kinase SGK1. Moreover, FceRI-dependent degranulation is decreased in SGK1-deficient (sgkl) MCs. The present study addressed whether SGK1 is required for actin cytoskeleton rearrangement in MCs and whether modulation of actin architecture could underlie decreased degranulation of sgkl MCs.