TY - JOUR
T1 - Enhancement of smooth muscle contraction with protein phosphatase inhibitor 1
T2 - Activation of inhibitor 1 by cGMP-dependent protein kinase
AU - Tokui, Toshiya
AU - Brozovich, Frank
AU - Ando, Shoji
AU - Ikebe, Mitsuo
PY - 1996/3/27
Y1 - 1996/3/27
N2 - New method for purification of phosphatase inhibitor 1 (PPI-1) was developed which avoid the phosphorylation of PPI-1 during the purification and provides a high yield of highly pure preparation. Using this preparation, it was shown that PPI-1 was stoichiometrically phosphorylated by cGMP-dependent protein kinase at Thr-35 and the phosphorylated PPI-1 potently inhibited protein phosphatase 1. Addition of the phosphorylated PPI-1 to β-escin-skinned single smooth muscle cells resulted in force development of the cells at the submaximal pCa2+. The results suggest that the phosphorylation of PPI-1 can be the mechanism for modifying the Ca2+ sensitivity of smooth muscle contractile response.
AB - New method for purification of phosphatase inhibitor 1 (PPI-1) was developed which avoid the phosphorylation of PPI-1 during the purification and provides a high yield of highly pure preparation. Using this preparation, it was shown that PPI-1 was stoichiometrically phosphorylated by cGMP-dependent protein kinase at Thr-35 and the phosphorylated PPI-1 potently inhibited protein phosphatase 1. Addition of the phosphorylated PPI-1 to β-escin-skinned single smooth muscle cells resulted in force development of the cells at the submaximal pCa2+. The results suggest that the phosphorylation of PPI-1 can be the mechanism for modifying the Ca2+ sensitivity of smooth muscle contractile response.
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U2 - 10.1006/bbrc.1996.0480
DO - 10.1006/bbrc.1996.0480
M3 - Article
C2 - 8607841
AN - SCOPUS:0029934224
VL - 220
SP - 777
EP - 783
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 3
ER -