title: RhoA/rho-associated kinase mediates fibroblast contractile force generation.
abstract: The intracellular signals governing contractile force generation by non-muscle cells remain uncertain. Our aim was to test the hypothesis that the rhoA/rho-associated kinase signaling pathway is a principal mediator of contractile force generation in non-muscle cells. We measured myosin II regulatory light chain (MLC) phosphorylation and directly quantitated force generation by chicken embryo fibroblasts in the absence and presence of selective inhibitors of rhoA, and its downstream effector, rho-associated kinase. Inactivation of rhoA, with C3 transferase, inhibited serum-stimulated MLC phosphorylation and contractile force generation. Y-27632, an inhibitor of rho-associated kinase, reduced basal contractile tension, and inhibited both serum and endothelin-1 stimulated MLC phosphorylation and contractile force generation. The results of this study provide novel evidence indicating that the rhoA/rho-associated kinase signaling pathway is a principal mediator of MLC phosphorylation and consequent contractile force generation by non-muscle cells.
authors.affiliation: Department of Medicine, University of California Los Angeles School of Medicine, Los Angeles, California 90095, USA.
authors.forename: H F
authors.initials: HF
authors.lastname: Yee
authors.forename: A C
authors.initials: AC
authors.lastname: Melton
authors.forename: B N
authors.initials: BN
authors.lastname: Tran
mesh_terms: D036002:ADP Ribose Transferases / Q000494:pharmacology; D000577:Amides / Q000494:pharmacology; D000818:Animals; D001905:Botulinum Toxins; D002478:Cells, Cultured; D002642:Chick Embryo; D003470:Culture Media / Q000494:pharmacology; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D019332:Endothelin-1 / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005347:Fibroblasts / Q000166:cytology / Q000502:physiology*; D047908:Intracellular Signaling Peptides and Proteins; D018994:Myosin Light Chains / Q000187:drug effects / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011725:Pyridines / Q000494:pharmacology; D013997:Time Factors; D054460:rho-Associated Kinases; D020742:rhoA GTP-Binding Protein / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D000577:Amides; D003470:Culture Media; D016895:Culture Media, Serum-Free; D019332:Endothelin-1; D004791:Enzyme Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; D018994:Myosin Light Chains; D011725:Pyridines; C108830:Y 27632; D036002:ADP Ribose Transferases; C063007:exoenzyme C3, Clostridium botulinum; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D001905:Botulinum Toxins; D020742:rhoA GTP-Binding Protein