Ribosomal S6 Kinase 1 (RSK1, S6K-alpha 1, 90 kDa Ribosomal Protein S6 Kinase 1, MAP kinase-activated protein kinase 1a, or MAPKAPK1A) is an immediate downstream effector of mitogen activated protein kinases and therefore promotes cell proliferation and survival. It has serine/threonine kinase activity and may play a role in mediating the growth-factor and stress-induced activation of the transcription factor CREB. The C-terminal region of RSK1 is reported to be an ERK docking site, where serine 732 phosphorylation status is critical for RSK1 activation. When serine 732 is not phosphorylated, ERK1/2 binds to the ERK docking site of RSK1, and upon stimulation, activates RSK1. The activated RSK1 then autophosphorylates serine 732, leading to the dissociation of ERK from RSK1 and termination of activation by ERK. RSK1 is studied in cancer research and is known to inactive tumor supressor complexes and death kinases.
This affinity purified antibody was prepared from whole rabbit serum produced by repeated immunizations with a synthetic peptide corresponding to a region near the C-terminal end of human RSK1 protein.