Modulation of actomyosin ATPase by goniodomin A differs in types of cardiac myosin.
Goniodomin A causes the conformational change of actin to modify actomyosin ATPase activity [Furukawa, K.-I., Sakai, K., Watanabe, S., Maruyama, K., Murakami, M., Yamaguchi, K., Ohizumi, Y., 1993. Goniodomin A induces modulation of actomyosin ATPase activity mediated through conformational change of actin. J. Biol. Chem. 268, 26026-26031]. Goniodomin A inhibited the ATPase activities of atrial myofibrils, myosin B and reconstituted actomyosin in a concentration-dependent manner. Interestingly, these ATPase activities of ventricular muscle were enhanced by goniodomin A (3 x 10(-8)-3 x 10(-7) M), but were decreased when the concentration was further raised. The stimulatory effect of goniodomin A was significantly inhibited by troponin tropomyosin complex. These results suggest that goniodomin A affects actin to modify cardiac actomyosin ATPase activity, and that this modulation differs in types of cardiac myosin.
Yasuda
M
M
Department of Pharmacology, School of Pharmaceutical Sciences, Showa University, Tokyo, Japan.
Nakatani
K
K
Matsunaga
K
K
Murakami
M
M
Momose
K
K
Ohizumi
Y
Y
D000818:Animals; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004987:Ethers / Q000494:pharmacology*; D006168:Guinea Pigs; D018942:Macrolides / Q000494:pharmacology*; D008297:Male; D009206:Myocardium / Q000201:enzymology / Q000378:metabolism*; D009218:Myosins / Q000037:antagonists & inhibitors / Q000378:metabolism*
D004791:Enzyme Inhibitors; D004987:Ethers; D018942:Macrolides; C059668:goniodomin A; D009218:Myosins