title: Rho-kinase regulates myosin II activation in MDCK cells during recovery after ATP depletion.
abstract: Alterations in the actin cytoskeleton of renal tubular epithelial cells during periods of ischemic injury and recovery have important consequences for normal cell and kidney function. Myosin II has been demonstrated to be an important effector in organizing basal actin structures in some cell types. ATP depletion in vitro has been demonstrated to recapitulate alterations of the actin cytoskeleton in renal tubular epithelial cells observed during renal ischemia in vivo. We utilized this reversible cell culture model of ischemia to examine the correlation of the activation state and cellular distribution of myosin II with disruption of actin stress fibers in Madin-Darby canine kidney (MDCK) cells during ATP depletion and recovery from ATP depletion. We found that myosin II inactivation occurs rapidly and precedes dissociation of myosin II from actin stress fibers during ATP depletion. Myosin II activation temporally correlates with colocalization of myosin II to reorganizing stress fibers during recovery from ATP depletion. Furthermore, myosin activation and actin stress fiber formation were found to be Rho-associated Ser/Thr protein kinase dependent during recovery from ATP depletion.
authors.affiliation: Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA. tsutton2@iupui.edu
authors.forename: T A
authors.initials: TA
authors.lastname: Sutton
authors.forename: H E
authors.initials: HE
authors.lastname: Mang
authors.forename: S J
authors.initials: SJ
authors.lastname: Atkinson
mesh_terms: D000199:Actins / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism*; D000577:Amides / Q000494:pharmacology; D000818:Animals; D000968:Antimycin A / Q000494:pharmacology; D015687:Cell Hypoxia / Q000187:drug effects; D002460:Cell Line; D004285:Dogs; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006160:Guanosine Triphosphate / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D007668:Kidney; D007700:Kinetics; D018613:Microscopy, Confocal; D024462:Myosin Type II / Q000378:metabolism*; D009219:Myosin-Light-Chain Kinase / Q000037:antagonists & inhibitors; D010710:Phosphates / Q000378:metabolism; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011725:Pyridines / Q000494:pharmacology; D022502:Stress Fibers / Q000378:metabolism; D054460:rho-Associated Kinases
chemical_list: D000199:Actins; D000577:Amides; D004791:Enzyme Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; D010710:Phosphates; D011725:Pyridines; C108830:Y 27632; D000968:Antimycin A; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D009219:Myosin-Light-Chain Kinase; D024462:Myosin Type II