多胺盐酸盐对整合到核小体核心颗粒中的磷酸化H2B组蛋白去磷酸化的影响。

Effects of polyamine hydrochlorides on dephosphorylation of phosphorylated H2B histone integrated into nucleosome core particles.

作者信息

Kinohara N, Usui H, Yoshikawa K, Takeda M

出版信息

J Biochem. 1984 Feb;95(2):597-600. doi: 10.1093/oxfordjournals.jbchem.a134646.

DOI:10.1093/oxfordjournals.jbchem.a134646

Abstract

The rate of dephosphorylation of isolated P-H2B histone by pig heart phosphoprotein phosphatase (Mr = 224,000) and its catalytic subunit (Mr = 31,000) was suppressed more than 95% at low ionic strength when the substrate was integrated into nucleosome core particles. The suppressed rate was increased 13-43-fold by polyamine hydrochlorides and Mg(CH3COO)2 at the optimal ionic strength of 0.2-0.38 M. Phosphatase activity toward integrated P-H2B histone was distributed in both rat liver cytosol and nuclear extracts. The phosphatase activities in these fractions showed similar specific activities and were also increased 10-32-fold by 10 mM spermine.4HCl.

摘要

当底物整合到核小体核心颗粒中时，在低离子强度下，猪心磷酸蛋白磷酸酶（Mr = 224,000）及其催化亚基（Mr = 31,000）对分离出的磷酸化组蛋白H2B的去磷酸化速率被抑制了95%以上。在0.2 - 0.38 M的最佳离子强度下，多胺盐酸盐和醋酸镁可使被抑制的速率提高13 - 43倍。对整合的磷酸化组蛋白H2B的磷酸酶活性分布在大鼠肝脏胞质溶胶和核提取物中。这些组分中的磷酸酶活性表现出相似的比活性，并且在加入10 mM精胺·4HCl后也提高了10 - 32倍。