Activation of Xenopus Chk1 by mutagenesis of threonine‐377

FEBS Letters

Dunphy, William G¹  Wang, Sophie X¹ 

[1] Division of Biology 216-76, Howard Hughes Medical Institute, California Institute of Technology, 1200 East California Blvd., Pasadena, CA 91125, USA

关键词: Chk1;    Phosphorylation;    Mitosis;    Cdc25;    Checkpoint control;   

DOI  :  10.1016/S0014-5793(00)02370-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Xenopus Chk1 (Xchk1) is required for the checkpoint-associated delay of the cell cycle in frog egg extracts containing unreplicated or UV-damaged DNA. Phosphorylation of Xchk1 at multiple sites in the SQ/TQ domain (residues 314–366) in response to unreplicated or UV-damaged DNA results in elevation of its kinase activity. We have found that mutagenesis of Thr-377 in the conserved Thr–Arg–Phe (TRF) motif of Xchk1 also leads to a substantial increase in kinase activity. Thr-377 does not appear to be a site of phosphorylation in Xchk1. These findings suggest that Thr-377 may play a role in suppressing the activity of Xchk1.

【 授权许可】

Unknown