Chk1, active, Recombinant, Human (CHEK1, Cell Cycle Checkpoint Kinase)

Chk1 is a 56kD Serine/Threonine protein kinase that was originally identified in fission yeast to play a role in activation of the DNA damage checkpoint in the G2 phase of the cell cycle (1). Chk1 appears to function downstream of several of the known fission yeast checkpoint gene products, including that encoded by Rad3, a gene with sequence similarity to the ATM gene mutated in patients with ataxia telangiectasia (2). Source: Recombinant full-length human Chk1 was expressed by baculovirus in Sf9 insect cells using an N-terminal GST tag. The gene accession number is NM_001274. Molecular Mass: The approximate molecular weight is 82kD (see Figure 1 below). Activity: The specific activity of Chk1 was determined to be 195 nmol/min/mg using a synthetic peptide substrate (KKKVSRSGLYRSPSMPENLNRPR). Storage: This product is stable at -70°C for at least 6 months from the date of receipt. For optimal storage, aliquot into smaller quantities after centrifugation and store at recommended temperature. Avoid repeated freeze-thaw cycles.