Methanol traps the troponin-tropomyosin-actin complex in an "off-state".
We have investigated the effect of methanol at concentrations below 15% (v/v) on acto-heavy meromyosin (HMM)- and tropomyosin (Tm)-troponin (Tn)-acto-heavy meromyosin-ATPase activities. Methanol slightly enhanced ATPase activity of acto-HMM alone. It had no apparent effect on normalized Tm-Tn-acto-HMM-ATPase activity in the absence of Ca2+. In the presence of Ca2+, however, methanol markedly inhibited normalized Tm-Tn-acto-HMM ATPase activity. These results show that methanol affects the troponin-tropomyosin regulation of acto-HMM ATPase: methanol suppresses the Ca(2+)-sensitivity of the regulatory system and traps it in an "off-state."
Matsuura
Y
Y
Department of Physics, University of Tokyo.
Yoshimoto
Y
Y
Saeki
K
K
Wakabayashi
T
T
D000199:Actins / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D000251:Adenosine Triphosphatases / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D007700:Kinetics; D000432:Methanol / Q000494:pharmacology*; D008961:Models, Structural; D018482:Muscle, Skeletal / Q000378:metabolism; D011485:Protein Binding; D011817:Rabbits; D014335:Tropomyosin / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D014336:Troponin / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*
D000199:Actins; D014335:Tropomyosin; D014336:Troponin; D000251:Adenosine Triphosphatases; D000432:Methanol