Anti-Rsk 2/MAPKAP Kinase 1b/RPS6KA3 Picoband® Antibody

Ribosomal protein S6 kinase, 90kDa, polypeptide 3, also known as RPS6KA3, is an enzyme that in humans is encoded by the RPS6KA3 gene. It is mapped to Xp22.12. This gene 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. Mutations in this gene have been associated with Coffin-Lowry syndrome (CLS) .

Ribosomal protein S6 kinase alpha-3; S6K-alpha-3; 90 kDa ribosomal protein S6 kinase 3; p90-RSK 3; P90rsk3; Insulin-stimulated protein kinase 1; ISPK-1; MAP kinase-activated protein kinase 1b; MAPK-activated protein kinase 1b; MAPKAP kinase 1b; MAPKAPK-1b; Ribosomal S6 kinase 2; RSK-2; pp90RSK2; RPS6KA3; ISPK1; MAPKAPK1B; RSK2

Auditory System, Domain Families, Epigenetics and Nuclear Signaling, Hlh/Leucine Zipper, Neurogenesis, Neurology Process, Neuroscience, Nuclear, Sensory System, Signaling Pathways, Stem Cells, Transcription

Serine/threonine-protein kinase that acts downstream of ERK (MAPK1/ERK2 and MAPK3/ERK1) signaling and mediates mitogenic and stress-induced activation of the transcription factors CREB1, ETV1/ER81 and NR4A1/NUR77, regulates translation through RPS6 and EIF4B phosphorylation, and mediates cellular proliferation, survival, and differentiation by modulating mTOR signaling and repressing pro-apoptotic function of BAD and DAPK1. In fibroblast, is required for EGF-stimulated phosphorylation of CREB1 and histone H3 at 'Ser-10', which results in the subsequent transcriptional activation of several immediate-early genes. In response to mitogenic stimulation (EGF and PMA), phosphorylates and activates NR4A1/NUR77 and ETV1/ER81 transcription factors and the cofactor CREBBP. Upon insulin-derived signal, acts inly on the transcription regulation of several genes by phosphorylating GSK3B at 'Ser-9' and inhibiting its activity. Phosphorylates RPS6 in response to serum or EGF via an mTOR-independent mechanism and promotes translation initiation by facilitating assembly of the preinitiation complex. In response to insulin, phosphorylates EIF4B, enhancing EIF4B affinity for the EIF3 complex and stimulating cap-dependent translation. Is involved in the mTOR nutrient-sensing pathway by ly phosphorylating TSC2 at 'Ser-1798', which potently inhibits TSC2 ability to suppress mTOR signaling, and mediates phosphorylation of RPTOR, which regulates mTORC1 activity and may promote rapamycin-sensitive signaling independently of the PI3K/AKT pathway. Mediates cell survival by phosphorylating the pro-apoptotic proteins BAD and DAPK1 and suppressing their pro-apoptotic function. Promotes the survival of hepatic stellate cells by phosphorylating CEBPB in response to the hepatotoxin carbon tetrachloride (CCl4) . Is involved in cell cycle regulation by phosphorylating the CDK inhibitor CDKN1B, which promotes CDKN1B association with 14-3-3 proteins and prevents its translocation to the nucleus and inhibition of G1 progression. In LPS-stimulated dendritic cells, is involved in TLR4-induced macropinocytosis, and in myeloma cells, acts as effector of FGFR3-mediated transformation signaling, after phosphorylation at Tyr-529 by FGFR3. Negatively regulates EGF-induced MAPK1/3 phosphorylation via phosphorylation of SOS1. Phosphorylates SOS1 at 'Ser-1134' and 'Ser-1161' that create YWHAB and YWHAE binding sites and which contribute to the negative regulation of MAPK1/3 phosphorylation. Phosphorylates EPHA2 at 'Ser-897', the RPS6KA-EPHA2 signaling pathway controls cell migration .

1. Delaunoy, J.-P., Abidi, F., Zeniou, M., Jacquot, S., Merienne, K., Pannetier, S., Schmitt, M., Schwartz, C. E., Hanauer, A. Mutations in the X-linked RSK2 gene (RPS6KA3) in patients with Coffin-Lowry syndrome. Hum. Mutat. 17: 103-116, 2001. 2. Delaunoy, J. P., Dubos, A., Marques Pereira, P., Hanauer, A. Identification of novel mutations in the RSK2 gene (RPS6KA3) in patients with Coffin-Lowry syndrome. Clin. Genet. 70: 161-166, 2006. 3. Field, M., Tarpey, P., Boyle, J., Edkins, S., Goodship, J., Luo, Y., Moon, J., Teague, J., Stratton, M. R., Futreal, P. A., Wooster, R., Raymond, F. L., Turner, G. Mutations in the RSK2 (RPS6KA3) gene cause Coffin-Lowry syndrome and nonsyndromic X-linked mental retardation. Clin. Genet. 70: 509-515, 2006.

Store at -20°C for one year from date of receipt. After reconstitution, at 4°C for one month. It can also be aliquotted and stored frozen at -20°C for six months. Avoid repeated freeze-thaw cycles.