This serine-threonine protein kinase number 19 is expressed from the MHC and predominantly in the nucleus. Protein kinases are involved in signal transduction pathways and play fundamental roles in the regulation of cell functions. This is a novel Ser/Thr protein kinase, that has Mn2+-dependent protein kinase activity that phosphorylates alpha -casein at Ser/Thr residues and histone at Ser residues. It can be covalently modified by the reactive ATP analogue 5'-p-fluorosulfonylbenzoyladenosine in the absence of ATP, and this modification is prevented in the presence of 1 mM ATP, indicating that the kinase domain of is capable of binding ATP [1].

1: The G11 gene located in the major histocompatibility complex encodes a novel nuclear serine/threonine protein kinase. Gomez-Escobar N, Chou CF, Lin WW, Hsieh SL, Campbell RD; J Biol Chem. 1998;273:30954-30960. PMID:9812991