Premium
DNA damage control: regulation and functions of checkpoint kinase 1
Author(s) -
Smits Veronique A. J.,
Gillespie David A.
Publication year - 2015
Publication title -
the febs journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.981
H-Index - 204
eISSN - 1742-4658
pISSN - 1742-464X
DOI - 10.1111/febs.13387
Subject(s) - g2 m dna damage checkpoint , microbiology and biotechnology , chek1 , biology , dna re replication , dna pkcs , dna replication , eukaryotic dna replication , dna damage , dna repair , mitosis , kinase , cell cycle checkpoint , genetics , protein kinase a , cell cycle , dna , gene
Checkpoint kinase 1 (Chk1) is a master regulator of the DNA damage and replication checkpoints in vertebrate cells. When activated via phosphorylation by its upstream regulatory kinase, ATR , Chk1 prevents cells with damaged or incompletely replicated DNA from entering mitosis, and acts to stabilize stalled replication forks and suppress replication origin firing when DNA synthesis is inhibited. Chk1 blocks mitosis by maintaining high levels of inhibitory tyrosine phosphorylation of the mitotic cyclin‐dependent kinase 1; however, the mechanisms that underlie replication fork stabilization and suppression of origin firing are less well defined. Although Chk1 function is evidently acutely regulated during these responses, how this occurs at the molecular level is incompletely understood. Recent evidence that Chk1 contains a ‘kinase‐associated 1’ domain within its regulatory C‐terminal region promises new insights. Additional modifications catalysed by other protein kinases, such as cyclin‐dependent kinase 1, Akt, and RSK , can combine with ubiquitylation to regulate Chk1 subcellular localization and protein stability. Interestingly, it is clear that Chk1 has less well‐defined functions in homologous recombination, chromatin modification, gene expression, spindle checkpoint proficiency, and cytokinesis. Here, we provide an overview of Chk1 regulation and functions, with an emphasis on unresolved questions that merit further research.