从绵羊主动脉细肌丝中分离出的钙调蛋白的特性。

Properties of calponin isolated from sheep aorta thin filaments.

作者信息

Marston S B

机构信息

Department of Cardiac Medicine, National Heart and Lung Institute, London, UK.

出版信息

FEBS Lett. 1991 Nov 4;292(1-2):179-82. doi: 10.1016/0014-5793(91)80862-w.

DOI:10.1016/0014-5793(91)80862-w

PMID:1835699

Abstract

Calponin, a 35 kDa actin-binding protein, was shown to be a normal component of 'native' thin filaments prepared from sheep aorta. Actin, tropomyosin, caldesmon and calponin were present in molar ratios 14:2:1:0.9. Calponin was isolated from thin filaments in yield 0.5 mg/100 mg thin filament protein. Calponin inhibited actomyosin ATPase up to 85%, half maximal at 0.2 calponin/actin. Inhibition did not depend on tropomyosin, Ca2+ or Ca2+ calmodulin. Caldesmon inhibited actomyosin with a 10-fold greater potency than calponin in the presence of tropomyosin and inhibition could be reversed by Ca2+ calmodulin under certain conditions. Calponin had no effect on caldesmon inhibition or the reversal of inhibition.

摘要

钙调蛋白是一种35 kDa的肌动蛋白结合蛋白，已被证明是从羊主动脉制备的“天然”细肌丝的正常组成成分。肌动蛋白、原肌球蛋白、钙调蛋白结合蛋白和钙调蛋白的摩尔比为14:2:1:0.9。从细肌丝中分离出钙调蛋白，产率为0.5 mg/100 mg细肌丝蛋白。钙调蛋白对肌动球蛋白ATP酶的抑制作用高达85%，在钙调蛋白/肌动蛋白为0.2时达到半数最大抑制。抑制作用不依赖于原肌球蛋白、Ca2+或Ca2+钙调蛋白。在存在原肌球蛋白的情况下，钙调蛋白结合蛋白对肌动球蛋白的抑制效力比钙调蛋白高10倍，在某些条件下，Ca2+钙调蛋白可逆转这种抑制作用。钙调蛋白对钙调蛋白结合蛋白的抑制作用或抑制作用的逆转没有影响。