?
 
C-terminal catalytic domain of the Serine/Threonine Kinases, Ribosomal S6 kinases STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. RSKs contain an N-terminal kinase domain (NTD) from the AGC family and a C-terminal kinase domain (CTD) from the CAMK family. They are activated by signaling inputs from extracellular regulated kinase (ERK) and phosphoinositide dependent kinase 1 (PDK1). ERK phosphorylates and activates the CTD of RSK, serving as a docking site for PDK1, which phosphorylates and activates the NTD, which in turn phosphorylates all known RSK substrates. RSKs act as downstream effectors of mitogen-activated protein kinase (MAPK) and play key roles in mitogen-activated cell growth, differentiation, and survival. Mammals possess four RSK isoforms (RSK1-4) from distinct genes. RSK proteins are also referred to as MAP kinase-activated protein kinases (MAPKAPKs), 90 kDa ribosomal protein S6 kinases (p90-RSKs), or p90S6Ks. The RSK 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.",