TLK1

TLK1 is a serine/threonine kinase of the tousled-like kinase (TLK) family, named after the Arabidopsis tousled mutant. It is activated during S phase, and its best-characterized substrates are the histone chaperones ASF1A and ASF1B and the DNA damage regulator Rad9, linking TLK1 to chromatin assembly, DNA replication and checkpoint control. Chk1- and Chk2-mediated phosphorylation inhibits TLK1 after DNA damage, transiently halting chromatin replication. TLK1 also participates in homologous recombination repair, and splice variants of TLK1 have been described in tumors.