Ribosomal Protein S6 Kinase Alpha 2 (RPS6Ka2)

RPS6Ka2 encodes a member of the RSK (ribosomal S6 kinase) family of serine/threonine kinases. This kinase contains 2 non-identical kinase catalytic domains and phosphorylates various substrates, including members of the mitogen-activated kinase (MAPK) signalling pathway. The activity of this protein has been implicated in controlling cell growth and differentiation. Alternate transcriptional splice variants, encoding different isoforms, have been characterized.The deduced 733-amino acid RSK3 protein has 84% and 75% sequence identity with RSK2 (RPS6KA3) and RSK1 (RPS6KA1), respectively. RSK3 has a unique N-terminal sequence which contains a putative bipartite nuclear localization signal. Immunoblot analysis of human cell lysates detected an 83-kD RSK protein.