PLCβ3 mediates cortactin interaction with WAVE2 in MCP1-induced actin polymerization and cell migration.
Monocyte chemotactic protein 1 (MCP1) stimulates vascular smooth muscle cell (VSMC) migration in vascular wall remodeling. However, the mechanisms underlying MCP1-induced VSMC migration have not been understood. Here we identify the signaling pathway associated with MCP1-induced human aortic smooth muscle cell (HASMC) migration. MCP1, a G protein-coupled receptor agonist, activates phosphorylation of cortactin on S405 and S418 residues in a time-dependent manner, and inhibition of its phosphorylation attenuates MCP1-induced HASMC G-actin polymerization, F-actin stress fiber formation, and migration. Cortactin phosphorylation on S405/S418 is found to be critical for its interaction with WAVE2, a member of the WASP family of cytoskeletal regulatory proteins required for cell migration. In addition, the MCP1-induced cortactin phosphorylation is dependent on PLCβ3-mediated PKCδ activation, and siRNA-mediated down-regulation of either of these molecules prevents cortactin interaction with WAVE2, affecting G-actin polymerization, F-actin stress fiber formation, and HASMC migration. Upstream, MCP1 activates CCR2 and Gαq/11 in a time-dependent manner, and down-regulation of their levels attenuates MCP1-induced PLCβ3 and PKCδ activation, cortactin phosphorylation, cortactin-WAVE2 interaction, G-actin polymerization, F-actin stress fiber formation, and HASMC migration. Together these findings demonstrate that phosphorylation of cortactin on S405 and S418 residues is required for its interaction with WAVE2 in MCP1-induced cytoskeleton remodeling, facilitating HASMC migration.
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163.
Jagadeesh
J
Janjanam
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163.
Giri Kumar
GK
Chandaka
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163.
Sivareddy
S
Kotla
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163 rgadipar@uthsc.edu.
Gadiparthi N
GN
Rao
D000199:Actins / Q000235:genetics / Q000378:metabolism; D001011:Aorta / Q000254:growth & development / Q000378:metabolism; D002465:Cell Movement / Q000235:genetics*; D018932:Chemokine CCL2 / Q000235:genetics / Q000378:metabolism*; D051356:Cortactin / Q000235:genetics / Q000378:metabolism*; D003599:Cytoskeleton / Q000235:genetics / Q000378:metabolism; D006801:Humans; D018485:Muscle Fibers, Skeletal / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000254:growth & development* / Q000378:metabolism; D054799:Phospholipase C beta / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D051300:Wiskott-Aldrich Syndrome Protein Family / Q000378:metabolism
D000199:Actins; C111835:CCL2 protein, human; D018932:Chemokine CCL2; D051356:Cortactin; C120152:WASF2 protein, human; D051300:Wiskott-Aldrich Syndrome Protein Family; C518039:PLCB3 protein, human; D054799:Phospholipase C beta