被蛋白激酶C磷酸化的组蛋白H1是在磷酸酶1存在的情况下用于检测蛋白磷酸酶2A的选择性底物。

Histone H1 phosphorylated by protein kinase C is a selective substrate for the assay of protein phosphatase 2A in the presence of phosphatase 1.

作者信息

Jakes S, Schlender K K

机构信息

Department of Pharmacology, Medical College of Ohio, Toledo.

出版信息

Biochim Biophys Acta. 1988 Oct 13;967(1):11-6. doi: 10.1016/0304-4165(88)90182-1.

DOI:10.1016/0304-4165(88)90182-1

PMID:2844281

Abstract

A protein phosphatase assay, selective for protein phosphatase 2A, has been developed. Bovine histone H1 phosphorylated by protein kinase C and [gamma-32P]ATP, designated H1(C), was tested as the substrate for various preparations of protein phosphatases 1 and 2A. The phosphatase 2A preparations were 10-60-times more active with H1(C) as the substrate when compared to phosphorylase a. The phosphatase 1 enzymes showed very little dephosphorylation of the H1(C) substrate, the activity being less than 5% of the phosphorylase phosphatase activity. This preference and selectivity was demonstrated for purified phosphatase preparations in addition to fresh tissue extracts. The assay provides a rapid, simple assay for the routine analysis of phosphatase 2A in the presence of phosphatase 1, without the use of heat-stable inhibitor proteins.

摘要

已开发出一种对蛋白磷酸酶2A具有选择性的蛋白磷酸酶检测方法。用蛋白激酶C和[γ-32P]ATP磷酸化的牛组蛋白H1，命名为H1(C)，被用作蛋白磷酸酶1和2A各种制剂的底物进行测试。与磷酸化酶a相比，以H1(C)为底物时，蛋白磷酸酶2A制剂的活性高10至60倍。蛋白磷酸酶1对H1(C)底物的去磷酸化作用非常小，其活性低于磷酸化酶磷酸酶活性的5%。除新鲜组织提取物外，纯化的磷酸酶制剂也表现出这种偏好和选择性。该检测方法可在存在蛋白磷酸酶1的情况下，对蛋白磷酸酶2A进行常规分析，无需使用热稳定抑制蛋白，具有快速、简便的特点。