Catalytic domain of the Serine/Threonine Kinase, Protein Kinase B alpha (also called Akt1)
STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. PKB-alpha is predominantly expressed in endothelial cells. It is critical for the regulation of angiogenesis and the maintenance of vascular integrity. It also plays a role in adipocyte differentiation. Mice deficient in PKB-alpha exhibit perinatal morbidity, growth retardation, reduction in body weight accompanied by reduced sizes of multiple organs, and enhanced apoptosis in some cell types. PKB-alpha activity has been reported to be frequently elevated in breast and prostate cancers. In some cancer cells, PKB-alpha may act as a suppressor of metastasis. PKB contains an N-terminal pleckstrin homology (PH) domain and a C-terminal catalytic domain. The PKB-alpha 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.
Jiyao W et al.(2023). "The conserved domain database in 2023.",