Catalytic domain of the Serine/Threonine Kinase, p38delta Mitogen-Activated Protein Kinase (also called MAPK13)
STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. p38delta/MAPK13 is found in skeletal muscle, heart, lung, testis, pancreas, and small intestine. It regulates microtubule function by phosphorylating Tau. It activates the c-jun promoter and plays a role in G2 cell cycle arrest. It also controls the degration of c-Myb, which is associated with myeloid leukemia and poor prognosis in colorectal cancer. p38delta is the main isoform involved in regulating the differentiation and apoptosis of keratinocytes. p38 kinases are MAPKs, serving as important mediators of cellular responses to extracellular signals. They are activated by the MAPK kinases MKK3 and MKK6, which in turn are activated by upstream MAPK kinase kinases including TAK1, ASK1, and MLK3, in response to cellular stresses or inflammatory cytokines. The p38delta subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.
Comment:includes ATP binding and substrate binding sites
Comment:based on the structure of human CDK2 bound with ATP and substrate peptide, on structures of p38alpha and p38beta bound with inhibitors, and on the structure of human p38gamma bound with MgAMP-PNP.