CK1 epsilon, Active

CK1? is a member of the CK1 family of serine/threonine protein kinases which play an important role in diverse cell processes, including DNA replication and repair. CK1? is a regulator of Yes-associated protein (YAP) transcription coactivator which is a key regulator of organ size and a candidate human oncogene. CK1? is activated by CCK2R and this then phosphorylates PKD2 at Ser244. Phosphorylation of PKD2 leads to its nuclear accumulation and efficient phosphorylation of nuclear PKD2 substrates in human gastric cancer cells (1). CKI? can phosphorylate topoisomerase (topo) IIalpha at serine-1106 and this regulates the enzyme activity and sensitivity to topo II-targeted drugs (2).