CHEK1
CHEK1 (checkpoint kinase 1, also known as CHK1) is a serine/threonine-protein kinase required for checkpoint-mediated cell cycle arrest after DNA damage or in the presence of unreplicated DNA. It integrates signals from the upstream kinases ATM and ATR. Browse Assay Genie's current range of CHEK1 research reagents below, or read on for the biology behind the target.
CHEK1 is a serine/threonine-protein kinase that sits at the centre of the DNA damage response. It is required for checkpoint-mediated cell cycle arrest when cells encounter DNA damage or unreplicated DNA. The kinase acts to integrate signals from ATM and ATR, two cell cycle proteins involved in DNA damage responses, which also associate with chromatin in meiotic prophase I. One defined substrate is the protein phosphatase CDC25A: phosphorylation of CDC25A by CHEK1 is required for cells to delay cell cycle progression in response to double-strand DNA breaks.
The CHEK1 gene encodes a member of the Ser/Thr protein kinase family, classed by UniProt within the protein kinase superfamily, CAMK Ser/Thr protein kinase family, NIM1 subfamily. HGNC places it in the checkpoint kinase 1 family, and the enzyme carries the classification EC 2.7.11.1. Its UniProt-annotated subcellular locations are the nucleus, chromosome, cytoplasm and the centrosome, a microtubule organising centre. Several alternatively spliced transcript variants have been described for the gene. One annotated isoform acts as an endogenous repressor of isoform 1: it interacts with and antagonises CHK1 to promote the S to G2/M phase transition. Orthologous genes, named Chek1, are recorded in both mouse and rat, which allows the pathway to be studied in rodent systems.
The official symbol CHEK1 replaced the older CHK1 designation, and earlier gene names, such as CHK1 (checkpoint, S.pombe) homolog, reflect its identification through homology with the fission yeast checkpoint gene. Researchers studying cell cycle control, replication stress and genome stability often examine CHEK1 alongside its partner kinase CHEK2, and alongside its regulators and substrates, to understand how cells pause division to repair damaged DNA.
CHEK1 is required for checkpoint-mediated arrest after DNA damage, making it a central readout for how cells detect and respond to genotoxic stress.
By phosphorylating CDC25A, CHEK1 enables cells to delay cell cycle progression in response to double-strand DNA breaks.
CHEK1 integrates signals from ATM and ATR, so it is used to study how upstream damage sensors are coupled to downstream arrest.
CHEK1 acts when unreplicated DNA is present, and its upstream kinases associate with chromatin in meiotic prophase I.
CHEK1 is a serine/threonine-protein kinase required for checkpoint-mediated cell cycle arrest in response to DNA damage or unreplicated DNA. It integrates signals from ATM and ATR, and its phosphorylation of CDC25A is required for cells to delay cell cycle progression after double-strand DNA breaks.
CHEK1 is also written CHK1, and the protein is named serine/threonine-protein kinase Chk1. Older names include CHK1 (checkpoint, S.pombe) homolog. Several alternatively spliced transcript variants exist, and one annotated isoform represses isoform 1 by antagonising CHK1 to promote the S to G2/M transition.
Yes. The gene has orthologues named Chek1 in both mouse and rat, and its older names refer to a homology with the S. pombe checkpoint gene. Check the datasheet of any product for its validated reactivity.
Partner checkpoint kinases, upstream DNA damage sensors and cell cycle regulators related to CHEK1 with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt O14757; product specifications from Assay Genie datasheets.