p90 Ribosomal S6 kinases‐ eclectic members of the human kinome

Abstract

The p90 ribosomal S6 kinase (RPS6KA1-6; RSK1-6) family represents an important family of conserved serine-threonine kinases among the higher eukaryotes. RSKs are identified by the presence of two non-identical and active kinase domains that is unique amongst the kinome. These kinases are involved in a multitude of essential processes in the cell, ranging from apoptosis and transcriptional regulation and activation of immediate early genes to the maintenance of the cell cycle and growth. They are also important in the regulation of the cell cycle in G2, meiosis I and II. The mutation and loss of catalytic activity of RSK2 causes Coffin-Lowry syndrome. This review provides a concise and focused perspective on the current understanding of the function of RSKs and their substrates.