Association of syntenin-1 with M-RIP polarizes Rac-1 activation during chemotaxis and immune interactions

作者:Sala Valdes Monica; Gordon Alonso Monica; Tejera Emilio; Ibanez Anna; Roman Cabrero J; Ursa Angeles; Mittelbrunn Maria; Lozano Francisco; Sanchez Madrid Francisco; Yanez Mo Maria*
来源:Journal of Cell Science, 2012, 125(5): 1235-1246.
DOI:10.1242/jcs.094912

摘要

In this study, we describe that the PDZ protein syntenin-1 is a crucial element for the generation of signaling asymmetry during the cellular response to polarized extracellular cues. We analyze the role of syntenin-1 in the control of asymmetry in two independent models of T cell polarization - the migratory response to chemoattractants and the establishment of cognate interactions between T cells and antigen-presenting cells (APCs). A combination of mutant, biochemical and siRNA approaches demonstrate that syntenin-1 is vital for the generation of polarized actin structures such as the leading edge and the contact zone with APCs. We found that the mechanism by which syntenin-1 controls actin polymerization relies on its mandatory role for activation of the small GTPase Rac. Syntenin-1 controls Rac through a specific association with the myosin phosphatase Rho interacting protein (M-RIP), which occurs in response to phosphorylation of syntenin-1 by Src at Tyr4. Our data indicate the key role of syntenin-1 in the generation of functional asymmetry in T cells and provide a novel mechanistic link between receptor activation and actin polymerization and accumulation in response to extracellular stimulation.

  • 出版日期2012-3-1