Serine/threonine-protein kinase which is required for checkpoint-mediated cell cycle arrest and activation of DNA repair in response to the presence of DNA damage or unreplicated DNA . May also negatively regulate cell cycle progression during unperturbed cell cycles . This regulation is achieved by a number of mechanisms that together help to preserve the integrity of the genome . Recognizes the substrate consensus sequence [R-X-X-S/T] . Binds to and phosphorylates CDC25A, CDC25B and CDC25C . Phosphorylation of CDC25A at ''Ser-178'' and ''Thr-507'' and phosphorylation of CDC25C at ''Ser-216'' creates binding sites for 14-3-3 proteins which inhibit CDC25A and CDC25C . Phosphorylation of CDC25A at ''Ser-76'', ''Ser-124'', ''Ser-178'', ''Ser-279'' and ''Ser-293'' promotes proteolysis of CDC25A . Phosphorylation of CDC25A at ''Ser-76'' primes the protein for subsequent phosphorylation at ''Ser-79'', ''Ser-82'' and ''Ser-88'' by NEK11, which is required for polyubiquitination and degradation of CDCD25A . Inhibition of CDC25 leads to increased inhibitory tyrosine phosphorylation of CDK-cyclin complexes and blocks cell cycle progression . Also phosphorylates NEK6 . Binds to and phosphorylates RAD51 at ''Thr-309'', which promotes the release of RAD51 from BRCA2 and enhances the association of RAD51 with chromatin, thereby promoting DNA repair by homologous recombination . Phosphorylates multiple sites within the C-terminus of TP53, which promotes activation of TP53 by acetylation and promotes cell cycle arrest and suppression of cellular proliferation . Also promotes repair of DNA cross-links through phosphorylation of FANCE . Binds to and phosphorylates TLK1 at ''Ser-743'', which prevents the TLK1-dependent phosphorylation of the chromatin assembly factor ASF1A . This may enhance chromatin assembly both in the presence or absence of DNA damage . May also play a role in replication fork maintenance through regulation of PCNA . May regulate the transcription of genes that regulate cell-cycle progression through the phosphorylation of histones (By similarity). Phosphorylates histone H3.1 (to form H3T11ph), which leads to epigenetic inhibition of a subset of genes (By similarity). May also phosphorylate RB1 to promote its interaction with the E2F family of transcription factors and subsequent cell cycle arrest . Phosphorylates SPRTN, promoting SPRTN recruitment to chromatin . Reduces replication stress and activates the G2/M checkpoint, by phosphorylating and inactivating PABIR1/FAM122A and promoting the serine/threonine-protein phosphatase 2A-mediated dephosphorylation and stabilization of WEE1 levels and activity . .; [Isoform 2]: Endogenous repressor of isoform 1, interacts with, and antagonizes CHK1 to promote the S to G2/M phase transition. .

Serine/threonine-protein kinase Chk1 (EC 2.7.11.1) (CHK1 checkpoint homolog) (Cell cycle checkpoint kinase) (Checkpoint kinase-1),CHEK1 CHK1

o14757

Mouse

Monoclonal

IgG2b

KGAKRPRVTSGGVSESPSGFSKHIQSNLDFSPVNSASSEENVKYSSSQPEPRTGLSLWDTSPSYIDKLVQGISFSQPTCP

Human

IHC,IP

IHC 1:100
IP 1:100

54kD

Supplied as solution in phosphate buffered saline containing 0.09% sodium azide

Store at +4°C short term. Store at -20°C long term. Avoid freeze / thaw cycle.