A functional interaction between CPI-17 and RACK1 proteins in bronchial smooth muscle cells.
CPI-17 is a phosphorylation-dependent inhibitor of smooth muscle myosin light chain. Using yeast two-hybrid system, we have identified the receptor for activated C kinase 1 (RACK1) as a novel interaction partner of CPI-17. The direct interaction and co-localization of CPI-17 with RACK1 were confirmed by immunoprecipitation and confocal microscopy analysis, respectively. An in vitro assay system using recombinant/purified proteins revealed that the PKC-mediated phosphorylation of CPI-17 was augmented in the presence of RACK1. These results suggest that RACK1 may play a role in PKC/CPI-17 signaling pathway.
Chiba
Yoshihiko
Y
Department of Pharmacology, School of Pharmacy, Hoshi University, Tokyo, Japan. chiba@hoshi.ac.jp
Tanabe
Miki
M
Sakai
Hiroyasu
H
Kimura
Shioko
S
Misawa
Miwa
M
D001980:Bronchi / Q000378:metabolism*; D002460:Cell Line; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D047468:Immunoprecipitation; D047908:Intracellular Signaling Peptides and Proteins; D009124:Muscle Proteins; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000378:metabolism*; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D000075370:Receptors for Activated C Kinase; D011956:Receptors, Cell Surface / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
D047908:Intracellular Signaling Peptides and Proteins; D009124:Muscle Proteins; D009363:Neoplasm Proteins; C107507:PPP1R14A protein, human; C419368:RACK1 protein, human; D000075370:Receptors for Activated C Kinase; D011956:Receptors, Cell Surface; D010749:Phosphoprotein Phosphatases; D019204:GTP-Binding Proteins