RPS6Ks
The RPS6Ks (ribosomal S6 kinases) family comprises growth factor-regulated serine/threonine kinases, known also as p90(rsk). Homologs of RPS6Ks exist in several species.
In humans, the RPS6Ks family contains 3 closely regulated members: RPS6KA1 (previous RSK1) (MIM.601684), RPS6KA2 (previous RSK3) (MIM.601685) and RPS6KA3 (previous RSK2) (MIM.300075).
The highly conserved feature of all members of the RPS6Ks family is the presence of 2 nonidentical kinase catalytic domains.
RPS6Ks are implicated in the activation of the mitogen-activated kinase cascade through MAP kinases kinases (MAP2Ks) and the stimulation of cell proliferation (at the transition between phases G0 and G1 of the cell cycle) and differentiation.