TROPONIN-TROPOMYOSIN INTERACTIONS - FLUORESCENCE STUDIES OF THE BINDING OF TROPONIN, TROPONIN-T, AND CHYMOTRYPTIC TROPONIN-T FRAGMENTS TO SPECIFICALLY LABELED TROPOMYOSIN
TROPONIN-TROPOMYOSIN INTERACTIONS - FLUORESCENCE STUDIES OF THE BINDING OF TROPONIN, TROPONIN-T, AND CHYMOTRYPTIC TROPONIN-T FRAGMENTS TO SPECIFICALLY LABELED TROPOMYOSIN
复制标题
DOI：
10.1021/bi00305a018
复制
发表时间：
1984-01-01
期刊：
影响因子：
2.9
通讯作者：
LEHRER, SS
中科院分区：
文献类型：
--
作者：
MORRIS, EP;LEHRER, SS
[兔]肌钙蛋白和原肌球蛋白之间的相互作用进行了研究，通过荧光探针，N-（1-苯胺基萘-4-基）马来酰亚胺（ANM），连接到半胱氨酸-190残基的原肌球蛋白。肌钙蛋白和肌钙蛋白T与ANM-原肌球蛋白的结合产生标记荧光的显著增加。结合曲线的分析表明，肌钙蛋白和肌钙蛋白T均以1：1的化学计量结合。获得肌钙蛋白T的几个糜蛋白酶片段，并通过消化分离的肌钙蛋白T或整个肌钙蛋白进行表征。肌钙蛋白T的N端片段（略小于整个分子的2/3）与原肌球蛋白结合，而不影响标记荧光;由肌钙蛋白T分子其余部分组成的C端片段导致标记荧光显著增强。从整个肌钙蛋白中分离出含有C-末端肌钙蛋白T片段以及肌钙蛋白I和肌钙蛋白C的复合物，其也增强了标记荧光。这些观察结果表明肌钙蛋白T和原肌球蛋白之间的附着区域延长。
The interaction between [rabbit] troponin and tropomyosin was studied by means of a fluorescent probe, N-(1-anilinonaphth-4-yl)maleimide (ANM), attached to the cysteine-190 residues of tropomyosin. The binding of troponin and troponin T to ANM-tropomyosin produces substantial increases in the label fluorescence. Analysis of the binding profiles indicates that both troponin and troponin T bind with a 1:1 stoichiometry. Several chymotryptic fragments of troponin T were obtained and characterized by digestion of isolated troponin T or whole troponin. An N-terminal fragment from troponin T which is slightly < 2/3 of the whole molecule binds to tropomyosin without affecting the label fluorescence; a C-terminal fragment composed of the rest of the troponin T molecule causes a substantial enhancement of the label fluorescence. A complex containing the C-terminal troponin T fragment together with troponin I and troponin C was isolated from whole troponin, which also enhanced the label fluorescence. These observations indicate an elongated region of attachment between troponin T and tropomyosin.