MODULATION OF SMOOTH-MUSCLE ACTOMYOSIN ATPASE BY THIN FILAMENT ASSOCIATED PROTEINS
MODULATION OF SMOOTH-MUSCLE ACTOMYOSIN ATPASE BY THIN FILAMENT ASSOCIATED PROTEINS
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DOI：
10.1016/0006-291x(86)90426-2
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发表时间：
1986-05-14
影响因子：
3.1
通讯作者：
CHACKO, S
中科院分区：
文献类型：
--
作者：
HORIUCHI, KY;MIYATA, H;CHACKO, S
Caldesmon与砂囊肌动蛋白和含有一定量原肌凝蛋白的肌动蛋白相结合。当肌动蛋白含有结合的原肌凝蛋白时，caldesmon与肌动蛋白的结合抑制肌动蛋白活化磷酸化肌凝蛋白的mg - atp酶活性。这种抑制的逆转需要Ca2+钙调素；但它的发生没有完全释放束缚的caldesmon。虽然caldesmon的磷酸化在atp酶测定中发生，但caldesmon的磷酸化与被抑制的肌动球蛋白atp酶的释放之间的直接相关性并没有一致观察到。
Caldesmon binds equally to both gizzard actin and actin containing stoichiometric amounts of bound tropomyosin. The binding of caldesmon to actin inhibits the actin-activation of the Mg-ATPase activity of phosphorylated myosin when the actin contains bound tropomyosin. The reversal of this inhibiton requires Ca2+-calmodulin; but it occurs without complete release of bound caldesmon. Although phosphorylation of the caldesmon occurs during the ATPase assay, a direct correlation between caldesmon phosphorylation and the release of the inhibited actomyosin ATPase is not consistently observed.