Inhibition of protein kinase C by N-myristoylated peptide substrate analogs.
Inhibition of protein kinase C by N-myristoylated peptide substrate analogs.
复制标题
DOI：
10.1021/bi00095a020
复制
发表时间：
1993-11
期刊：
影响因子：
2.9
通讯作者：
N. Ward;C. O'brian
中科院分区：
文献类型：
--
作者：
N. Ward;C. O'brian
蛋白激酶C（PKC）是一个密切相关的磷脂依赖性蛋白激酶家族。PKC的完全活性的、磷脂非依赖性催化片段通过酶的有限蛋白水解产生。催化片段允许简化的测定系统用于分析与催化结构域相互作用的PKC抑制剂。最近，我们报道了合成肽底物Arg-Lys-Arg-Thr-Leu-Arg-Arg-Leu（RKRTLRRL）的N-肉豆蔻酰化将完全缺乏对PKC及其催化片段的组蛋白激酶反应的抑制活性的肽转化为有效抑制这两种反应的肽。N-豆蔻酰化没有改变肽作为PKC底物的效力，并且通过肽的N-豆蔻酰化获得对催化片段的抑制活性的基础仍然不清楚。在这份报告中，我们提出了一种N-肉豆蔻酰化肽抑制催化片段的机制，该机制是基于N-肉豆蔻酰-RKRTLRRL的几种非磷酸化类似物的抑制效力的比较，非磷酸化N-肉豆蔻酰-RKRTLRRL类似物抑制催化片段的组蛋白激酶活性的动力学分析，以及N-肉豆蔻酰化肽系列对PKC的内在ATP酶活性的抑制作用的分析。我们的研究结果支持了一种机制，其中N-豆蔻酰化肽抑制的催化片段结合PKC自由，但不是复杂的PKC-ATP，在蛋白质底物结合位点。（250字处删节）
Protein kinase C (PKC) is a family of closely related phospholipid-dependent protein kinases. A fully active, phospholipid-independent catalytic fragment of PKC is produced by limited proteolysis of the enzyme. The catalytic fragment allows a simplified assay system for the analysis of PKC inhibitors that interact with the catalytic domain. Recently, we reported that N-myristoylation of the synthetic peptide substrate Arg-Lys-Arg-Thr-Leu-Arg-Arg-Leu (RKRTLRRL) transformed a peptide that completely lacked inhibitory activity against the histone kinase reactions of PKC and its catalytic fragment into a peptide that potently inhibited both of these reactions. N-Myristoylation did not alter the potency of the peptide as a PKC substrate, and the basis for the acquisition of inhibitory activity against the catalytic fragment by N-myristoylation of the peptide remained unclear. In this report, we propose a mechanism for catalytic fragment inhibition by the N-myristoylated peptide that is based on a comparison of the inhibitory potencies of several nonphosphorylatable analogs of N-myristoyl-RKRTLRRL, a kinetic analysis of the inhibition of the histone kinase activity of the catalytic fragment by nonphosphorylatable N-myristoyl-RKRTLRRL analogs, and an analysis of the inhibitory effects of the N-myristoylated peptide series on the intrinsic ATPase activity of PKC. Our results support a mechanism in which the N-myristoylated peptides inhibit the catalytic fragment by binding to PKCfree, but not to the complex PKC-ATP, at the protein-substrate binding site.(ABSTRACT TRUNCATED AT 250 WORDS)