Phosphorylation of calponin mediated by protein kinase C in association with contraction in porcine coronary artery.
Calponin is an actin-associated regulatory protein in smooth muscle. We report that both endothelin-1 (ET-1) and phorbol 12, 13-dibutyrate (PDBu) caused a significant increase in phosphorylation of calponin during contraction of porcine coronary artery, while high levels of KCl were ineffective. This phosphorylation was predominantly catalyzed by activation of protein kinase C(PKC). In addition, the level of phosphorylation of calponin increased closely in association with the size of the contractile force induced by PDBu. Thus, the phosphorylation of calponin in vivo by PKC might modulate in part the contraction of smooth muscle that occurs in response to ET-1 or PDBu.
Mino
T
T
Department of Molecular and Cellular Pharmacology, Mie University School of Medicine, Japan.
Yuasa
U
U
Naka
M
M
Tanaka
T
T
D000818:Animals; D002135:Calcium-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D003331:Coronary Vessels / Q000187:drug effects / Q000502:physiology*; D015180:Electrophoresis, Gel, Two-Dimensional; D016232:Endothelins / Q000494:pharmacology; D066298:In Vitro Techniques; D007700:Kinetics; D008840:Microfilament Proteins; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology*; D009124:Muscle Proteins / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology*; D010449:Peptide Mapping; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology; D010748:Phosphopeptides / Q000302:isolation & purification; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism*; D013552:Swine; D000096985:Calponins
D002135:Calcium-Binding Proteins; D016232:Endothelins; D008840:Microfilament Proteins; D009124:Muscle Proteins; D015240:Phorbol 12,13-Dibutyrate; D010748:Phosphopeptides; D011493:Protein Kinase C; D000096985:Calponins