Description_x000D_ General description_x000D_ TLK1 or tousled-like kinase 1 is a nuclear serine/threonine kinase that is potentially involved in the regulation of chromatin assembly. TLK1 is first described in Arabidopsis. TLK1 is a novel target of the DNA damage checkpoint that is rapidly inactivated upon exposure to ionizing radiation (IR) and the inactivation is directly mediated by the S-phase DNA damage checkpoint. The suppression of TLK1 activity after double-strand breaks in the DNA, replication blockade, or low doses of ultraviolet irradiation requires ATM, NBS and CHK1._x000D_ Physical form_x000D_ Supplied in 50mM Tris-HCl, pH 7.5, 150mM NaCl, 10mM glutathione, 0.1mM EDTA, 0.25mM DTT, 0.1mM PMSF, 25% glycerol._x000D_ Preparation Note_x000D_ after opening, aliquot into smaller quantities and store at -70 °C. Avoid repeating handling and multiple freeze/thaw cycles_x000D_ Legal Information_x000D_ PRECISIO is a registered trademark of Sigma-Aldrich Co. LLC