Src Regulates Distinct Pathways for Cell Volume Control through Vav and Phospholipase CÎ

• Published in: The Journal of biological chemistry 2005-07, Vol.280 (27), p.25548
• Main Authors: Elisabeth T. Barfod, Ann L. Moore, Richard F. Melnick, Steven D. Lidofsky
• Format: Article
• Language: English
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.M411717200

Cell volume recovery in response to swelling requires reorganization of the cytoskeleton and fluid efflux. We have previously shown that electrolyte and fluid efflux via K + and Cl – channels is controlled by swelling-induced activation of phospholipase Cγ (PLCγ). Recently, integrin engagement has been suggested to trigger responses to swelling through activation of Rho family GTPases and Src kinases. Because both PLCγ and Rho GTPases can be regulated by Src during integrin-mediated cytoskeletal reorganization, we sought to identify swelling-induced Src effectors. Upon hypotonic challenge, Src was rapidly activated in transient plasma membrane protrusions, where it colocalized with Vav, an activator of Rho GTPases. Inhibition of Src with PP2 attenuated phosphorylation of Vav. PP2 also attenuated phosphorylation of PLCγ, and inhibited swelling-mediated activation of K + and Cl – channels and cell volume recovery. These findings suggest that swelling-induced Src regulates cytoskeletal dynamics, through Vav, and fluid efflux, through PLCγ, and thus can coordinate structural reorganization with fluid balance to maintain cellular integrity.