大鼠离体肝细胞核蛋白质磷酸化和去磷酸化的一些特性

Some characteristics of phosphorylation and dephosphorylation of proteins of isolated rat liver nuclei.

作者信息

Szeszák F

出版信息

Acta Biochim Biophys Acad Sci Hung. 1976;11(2-3):113-9.

Abstract

The phosphorylation and dephosphorylation reactions of the proteins of isolated rat liver nuclei were examined in the presence of ATP. It was shown that the plateau value of the phosphorus incorporation at high concentrations of ATP is the result of an equilibrium of phosphorylation and dephosphorylation. The data of 32P-labelling experiments and those of chemical determination of net change of phosphorus content were compared. The activity of an efficient protein phosphatase in rat liver nuclei is demonstrated. It was shown that the pool of protein-phosphorus in the nuclei is heterogeneous as regards its turnover rate. A protein-phosphorus fraction of high turnover dominates the picture of phosphorylation and dephosphorylation reactions when studied with [gamma-32P] ATP in vitro.

摘要

在ATP存在的情况下，对分离的大鼠肝细胞核蛋白质的磷酸化和去磷酸化反应进行了研究。结果表明，在高浓度ATP条件下磷掺入的平台值是磷酸化和去磷酸化平衡的结果。比较了32P标记实验的数据和磷含量净变化的化学测定数据。证实了大鼠肝细胞核中存在一种高效的蛋白质磷酸酶。结果表明，细胞核中蛋白质磷库在周转率方面是异质的。当在体外使用[γ-32P]ATP进行研究时，高周转率的蛋白质磷组分在磷酸化和去磷酸化反应中占主导地位。