PMID- 23737530 OWN - NLM STAT- MEDLINE DCOM- 20131104 LR - 20211021 IS - 1083-351X (Electronic) IS - 0021-9258 (Print) IS - 0021-9258 (Linking) VI - 288 IP - 30 DP - 2013 Jul 26 TI - Nuclear factor of activated T cells c1 mediates p21-activated kinase 1 activation in the modulation of chemokine-induced human aortic smooth muscle cell F-actin stress fiber formation, migration, and proliferation and injury-induced vascular wall remodeling. PG - 22150-62 LID - 10.1074/jbc.M113.454082 [doi] AB - Recent literature suggests that cyclin-dependent kinases (CDKs) mediate cell migration. However, the mechanisms were not known. Therefore, the objective of this study is to test whether cyclin/CDKs activate Pak1, an effector of Rac1, whose involvement in the modulation of cell migration and proliferation is well established. Monocyte chemotactic protein 1 (MCP1) induced Pak1 phosphorylation/activation in human aortic smooth muscle cells (HASMCs) in a delayed time-dependent manner. MCP1 also stimulated F-actin stress fiber formation in a delayed manner in HASMCs, as well as the migration and proliferation of these cells. Inhibition of Pak1 suppressed MCP1-induced HASMC F-actin stress fiber formation, migration, and proliferation. MCP1 induced cyclin D1 expression as well as CDK6 and CDK4 activities, and these effects were dependent on activation of NFATc1. Depletion of NFATc1, cyclin D1, CDK6, or CDK4 levels attenuated MCP1-induced Pak1 phosphorylation/activation and resulted in decreased HASMC F-actin stress fiber formation, migration, and proliferation. CDK4, which appeared to be activated downstream of CDK6, formed a complex with Pak1 in response to MCP1. MCP1 also activated Rac1 in a time-dependent manner, and depletion/inhibition of its levels/activation abrogated MCP1-induced NFATc1-cyclin D1-CDK6-CDK4-Pak1 signaling and, thereby, decreased HASMC F-actin stress fiber formation, migration, and proliferation. In addition, smooth muscle-specific deletion of NFATc1 led to decreased cyclin D1 expression and CDK6, CDK4, and Pak1 activities, resulting in reduced neointima formation in response to injury. Thus, these observations reveal that Pak1 is a downstream effector of CDK4 and Rac1-dependent, NFATc1-mediated cyclin D1 expression and CDK6 activity mediate this effect. In addition, smooth muscle-specific deletion of NFATc1 prevented the capacity of vascular smooth muscle cells for MCP-1-induced activation of the cyclin D1-CDK6-CDK4-Pak1 signaling axis, affecting their migration and proliferation in vitro and injury-induced neointima formation in vivo. FAU - Kundumani-Sridharan, Venkatesh AU - Kundumani-Sridharan V AD - Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA. FAU - Singh, Nikhlesh K AU - Singh NK FAU - Kumar, Sanjay AU - Kumar S FAU - Gadepalli, Ravisekhar AU - Gadepalli R FAU - Rao, Gadiparthi N AU - Rao GN LA - eng GR - R01 HL069908/HL/NHLBI NIH HHS/United States GR - R01 HL103575/HL/NHLBI NIH HHS/United States GR - HL103575/HL/NHLBI NIH HHS/United States GR - HL069908/HL/NHLBI NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural DEP - 20130604 PL - United States TA - J Biol Chem JT - The Journal of biological chemistry JID - 2985121R RN - 0 (Actins) RN - 0 (CCL2 protein, human) RN - 0 (Chemokine CCL2) RN - 0 (NFATC Transcription Factors) RN - 0 (NFATC1 protein, human) RN - 136601-57-5 (Cyclin D1) RN - EC 2.7.11.1 (PAK1 protein, human) RN - EC 2.7.11.1 (p21-Activated Kinases) RN - EC 2.7.11.22 (Cyclin-Dependent Kinase 4) RN - EC 2.7.11.22 (Cyclin-Dependent Kinase 6) SB - IM MH - Actins/metabolism MH - Animals MH - Aorta/pathology/physiopathology MH - Blotting, Western MH - Cell Movement/*drug effects MH - Cell Proliferation/*drug effects MH - Cells, Cultured MH - Chemokine CCL2/*pharmacology MH - Cyclin D1/genetics/metabolism MH - Cyclin-Dependent Kinase 4/genetics/metabolism MH - Cyclin-Dependent Kinase 6/genetics/metabolism MH - Enzyme Activation MH - Humans MH - Mice MH - Mice, Inbred C57BL MH - Mice, Transgenic MH - Microscopy, Fluorescence MH - Models, Biological MH - Myocytes, Smooth Muscle/*drug effects/metabolism MH - NFATC Transcription Factors/genetics/*metabolism MH - RNA Interference MH - Signal Transduction/drug effects MH - Stress Fibers/*metabolism MH - Vascular System Injuries/physiopathology MH - p21-Activated Kinases/*metabolism PMC - PMC3724667 OTO - NOTNLM OT - Cell Growth OT - Cell Migration OT - Cyclin-dependent Kinase (CDK) OT - NFAT Transcription Factor OT - Vascular Smooth Muscle Cells EDAT- 2013/06/06 06:00 MHDA- 2013/11/05 06:00 PMCR- 2014/07/26 CRDT- 2013/06/06 06:00 PHST- 2013/06/06 06:00 [entrez] PHST- 2013/06/06 06:00 [pubmed] PHST- 2013/11/05 06:00 [medline] PHST- 2014/07/26 00:00 [pmc-release] AID - S0021-9258(20)45508-5 [pii] AID - M113.454082 [pii] AID - 10.1074/jbc.M113.454082 [doi] PST - ppublish SO - J Biol Chem. 2013 Jul 26;288(30):22150-62. doi: 10.1074/jbc.M113.454082. Epub 2013 Jun 4.