Chk1 蛋白, Human (sf9, GST)

The serine/threonine protein kinase CHK1 is essential for checkpoint-mediated cell cycle arrest and DNA repair. It may negatively regulate cell cycle progression and maintain genomic integrity during the normal cell cycle. The kinase recognizes the consensus sequence [R-X-X-S/T] and phosphorylates CDC25A, CDC25B, and CDC25C. Phosphorylation of CDC25A inhibits its activity and promotes proteolysis, while increasing tyrosine phosphorylation of CDK-cyclin complexes. In addition, the kinase phosphorylates RAD51 and TP53, enhancing DNA repair and cell cycle arrest. Chk1 Protein, Human (sf9, GST) is the recombinant human-derived Chk1 protein, expressed by Sf9 insect cells , with N-GST labeled tag. The total length of Chk1 Protein, Human (sf9, GST) is 476 a.a., with molecular weight of ~80 kDa.

丝氨酸/苏氨酸蛋白激酶 CHK1 对于检查点介导的细胞周期停滞和 DNA 损伤或未复制 DNA 引起的 DNA 修复激活至关重要。它还可能在正常细胞周期中负面调节细胞周期进程，利用各种机制来维持基因组完整性。该激酶识别底物共识序列 [R-X-X-S/T] 并磷酸化 CDC25A、CDC25B 和 CDC25C。
CDC25A 在特定残基处的磷酸化会为 14-3-3 蛋白产生结合位点，从而抑制其活性，而额外的磷酸化会促进 CDC25A 的蛋白水解。抑制 CDC25 会导致 CDK-细胞周期蛋白复合物的酪氨酸磷酸化增加，从而阻止细胞周期进程。该激酶还会磷酸化 RAD51 和 TP53，分别增强 DNA 修复和促进细胞周期停滞。此外，它通过磷酸化 TLK1 来调节染色质组装，并可能通过 PCNA 调节参与复制叉的维持。它还可以磷酸化组蛋白 H3.1，导致某些基因的表观遗传抑制，并磷酸化 RB1 以促进其与 E2F 转录因子的相互作用。此外，它通过调节 PABIR1/FAM122A 和稳定 WEE1 水平和活性来减少复制压力并激活 G2/M 检查点。

The specific activity was determined to be > 15 nmol/min/mg using CHKtide peptide (KKKVSRSGLYRSPSMPENLNRPR) as substrate.

Human

Sf9 insect cells

N-GST

AAM78553.1 (M1-T476)

1111  [NCBI]

Approximately 80 kDa

Greater than 85% as determined by reducing SDS-PAGE

溶液.

Supplied as a 0.2 μm filtered solution of 20 mM Tris, 500 mM NaCl, pH 7.4, 10% glycerol, 2 mM GSH.

<1 EU/μg, determined by LAL method.

Please use rapid thawing with running water to thaw the protein.

Stored at -80°C for 1 year. It is stable at -20°C for 3 months after opening. It is recommended to freeze aliquots at -80°C for extended storage. Avoid repeated freeze-thaw cycles.

Shipping with dry ice.