RHODOPSIN KINASE INHIBITION BY RECOVERIN - FUNCTION OF RECOVERIN MYRISTOYLATION
RHODOPSIN KINASE INHIBITION BY RECOVERIN - FUNCTION OF RECOVERIN MYRISTOYLATION
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DOI：
10.1074/jbc.270.41.24127
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发表时间：
1995-10-13
影响因子：
4.8
通讯作者：
BOWNDS, MD
中科院分区：
文献类型：
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作者：
CALVERT, PD;KLENCHIN, VA;BOWNDS, MD
Recoverin是一种钙离子结合蛋白，可能通过赋予钙离子对视紫红质激酶的敏感性而在脊椎动物光感受器光适应中发挥作用。它的氨基末端的甘氨酸是异构酰化的(主要是肉豆蔻酰化的)。最近的研究表明，恢复素肉豆蔻酰化是其依赖于钙离子的膜结合和协同结合所必需的。我们已经解决了几个关于恢复肉豆蔻酰化在抑制视紫红质激酶方面的作用的问题。我们发现：1)恢复蛋白的肉豆蔻酸化不是视紫红质激酶抑制所必需的，2)恢复蛋白的肉豆蔻酸化导致视紫红质激酶抑制的协同的钙依赖，以及3)非肉豆蔻酸化的恢复蛋白上的每个钙结合位点部分抑制视紫红质激酶。已有的数据表明，活体视紫红质激酶抑制中的恢复素肉豆蔻酸化的功能是诱导强烈的钙依赖，并将这种依赖带入活体的生理钙浓度范围。
Recoverin is a Ca2+-binding protein that may play a role in vertebrate photoreceptor light adaptation by imparting Ca2+ sensitivity to rhodopsin kinase. It is heterogeneously acylated (mostly myristoylated) at its aminoterminal glycine. Recent studies have shown that recoverin myristoylation is necessary for its Ca2+-dependent membrane association and cooperative Ca2+ binding. We have addressed several issues concerning the role of recoverin myristoylation with respect to inhibition of rhodopsin kinase. We find that 1) myristoylation of recoverin is not necessary for inhibition of rhodopsin kinase, 2) myristoylation of recoverin induces a cooperative Ca2+-dependence for rhodopsin kinase inhibition, and 3) each Ca2+-binding site on the nonmyristoylated recoverin partially inhibits rhodopsin kinase. The available data suggest that the functions of recoverin myristoylation in the living rod are to induce a sharp Ca2+ dependence of rhodopsin kinase inhibition and to bring this dependence into the rod's physiological Ca2+ concentration range.