检查点激酶Chk1对蛋白激酶CK2调节性β亚基的磷酸化：体外CK2β磷酸化位点的鉴定

Phosphorylation of the regulatory beta-subunit of protein kinase CK2 by checkpoint kinase Chk1: identification of the in vitro CK2beta phosphorylation site.

作者信息

Kristensen Lars P, Larsen Martin R, Højrup Peter, Issinger Olaf-Georg, Guerra Barbara

机构信息

Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.

出版信息

FEBS Lett. 2004 Jul 2;569(1-3):217-23. doi: 10.1016/j.febslet.2004.05.069.

DOI:10.1016/j.febslet.2004.05.069

PMID:15225637

Abstract

The regulatory beta-subunit of protein kinase CK2 mediates the formation of the CK2 tetrameric form and it has functions independent of CK2 catalytic subunit through interaction with several intracellular proteins. Recently, we have shown that CK2beta associates with the human checkpoint kinase Chk1. In this study, we show that Chk1 specifically phosphorylates in vitro the regulatory beta-subunit of CK2. Chymotryptic peptides and mutational analyses have revealed that CK2beta is phosphorylated at Thr213. Formation of a stable complex between CK2beta and Chk1 is not affected by the modification of Thr213 but it does require the presence of an active Chk1 kinase.

摘要

蛋白激酶CK2的调节性β亚基介导CK2四聚体形式的形成，并且通过与几种细胞内蛋白质相互作用而具有独立于CK2催化亚基的功能。最近，我们已经表明CK2β与人类检查点激酶Chk1相关联。在本研究中，我们表明Chk1在体外特异性磷酸化CK2的调节性β亚基。胰凝乳蛋白酶肽段和突变分析表明CK2β在Thr213处被磷酸化。CK2β与Chk1之间稳定复合物的形成不受Thr213修饰的影响，但确实需要活性Chk1激酶的存在。