Conversion of a Ca2+-dependent myosin light chain kinase from skeletal muscle to a Ca2+-independent form.
Conversion of a Ca2+-dependent myosin light chain kinase from skeletal muscle to a Ca2+-independent form.
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Ca2 依赖性肌球蛋白轻链激酶从骨骼肌转化为 Ca2 不依赖性形式。
DOI：
10.1016/0006-291x(83)91206-8
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发表时间：
1983
影响因子：
3.1
通讯作者：
Hartshorne,DJ
中科院分区：
文献类型：
--
作者：
Srivastava,S;Hartshorne,DJ
兔骨骼肌球蛋白轻链激酶（myosin light chain kinase，myosin light chain在蛋白水解过程中占主导地位的条件是重要的，Ca 2+依赖性的损失是通过Ca 2 +-钙调蛋白-激酶复合物的水解实现的。使用肌球蛋白和分离的轻链作为底物，发现缺乏Ca 2+和钙调素依赖性。Ca 2+非依赖性形式（Mrapproximate 65，000）的比活性与天然酶的比活性相似，即，2 ~ 5 μmol磷酸转移min-1 mg-1激酶。65，000-道尔顿片段被cAMP依赖性蛋白激酶的催化亚基磷酸化，每个片段掺入约0.8摩尔磷酸盐。
The Ca2+- and calmodulin-dependent myosin light chain kinase of rabbit skeletal muscle was converted to a Ca2+-independent form by limited proteolysis with α-chymotrypsin. The conditions prevailing during proteolysis are important and the loss of Ca2+-dependence was achieved best by hydrolysis of the Ca2+-calmodulin-kinase complex. The lack of Ca2+- and calmodulin-dependence was found using both myosin and isolated light chains as substrates. The specific activity of the Ca2+-independent form (Mrapproximately 65,000) was similar to that of the native enzyme, i.e., 2 to 5 μmol phosphate transferred min−1mg−1kinase. The 65,000-dalton fragment was phosphorylated by the catalytic subunit of the cAMP-dependent protein kinase and approximately 0.8 moles phosphate were incorporated per fragment.