P23443

Background

Protein Name
Ribosomal protein S6 kinase beta-1
Gene Name
RPS6KB1
Organism
Homo sapiens

Annotations

Function
Serine/threonine-protein kinase that acts downstream of mTOR signaling in response to growth factors and nutrients to promote cell proliferation, cell growth and cell cycle progression. Regulates protein synthesis through phosphorylation of EIF4B, RPS6 and EEF2K, and contributes to cell survival by repressing the pro-apoptotic function of BAD. Under conditions of nutrient depletion, the inactive form associates with the EIF3 translation initiation complex. Upon mitogenic stimulation, phosphorylation by the mammalian target of rapamycin complex 1 (mTORC1) leads to dissociation from the EIF3 complex and activation. The active form then phosphorylates and activates several substrates in the pre-initiation complex, including the EIF2B complex and the cap-binding complex component EIF4B. Also controls translation initiation by phosphorylating a negative regulator of EIF4A, PDCD4, targeting it for ubiquitination and subsequent proteolysis. Promotes initiation of the pioneer round of protein synthesis by phosphorylating POLDIP3/SKAR. In response to IGF1, activates translation elongation by phosphorylating EEF2 kinase (EEF2K), which leads to its inhibition and thus activation of EEF2. Also plays a role in feedback regulation of mTORC2 by mTORC1 by phosphorylating RICTOR, resulting in the inhibition of mTORC2 and AKT1 signaling. Mediates cell survival by phosphorylating the pro-apoptotic protein BAD and suppressing its pro-apoptotic function. Phosphorylates mitochondrial URI1 leading to dissociation of a URI1-PPP1CC complex. The free mitochondrial PPP1CC can then dephosphorylate RPS6KB1 at Thr-412, which is proposed to be a negative feedback mechanism for the RPS6KB1 anti-apoptotic function. Mediates TNF-alpha-induced insulin resistance by phosphorylating IRS1 at multiple serine residues, resulting in accelerated degradation of IRS1. In cells lacking functional TSC1-2 complex, constitutively phosphorylates and inhibits GSK3B. May be involved in cytoskeletal rearrangement through binding to neurabin. Phosphorylates and activates the pyrimidine biosynthesis enzyme CAD, downstream of MTOR.

Mapping Statistics

Site Maximum Consensus Site Population Minimum Consensus Site Population Median Consensus Site Population
AAS 27 3 14.5
MT3 23 2 17.5
LBP 3 3 3.0
ATP 30 2 10.0
DFG 10 2 4.0
CMP 12 3 8.0
PMP 5 2 3.5
EDI 15 2 4.0
DRS 22 1 8.0
PDIG 18 2 8.0
PIF 18 17 17.5

Mapping Results

PDB ID Maximum Consensus Site Population
MPP site AAS site MT3 site LBP site ATP site DEF site DFG site CMP site PMP site EDI site DRS site PDIG site PIF site
Total Druggable Structures per Site 0 3 7 0 17 0 0 0 0 0 4 5 2
4L46 0 0 23 0 26 0 2 0 0 12 8 16 0
4RLO 0 27 0 0 23 0 10 0 0 0 19 3 0
3A62 0 0 5 0 20 0 7 8 0 2 14 18 0
3WF8 0 0 0 0 21 0 0 0 0 0 6 13 0
4L42 0 0 0 0 18 0 0 8 0 0 9 18 17
3WF6 0 0 0 0 24 0 8 4 0 2 9 8 0
3A61 0 0 0 0 18 0 2 0 0 15 17 18 0
3WF9 0 0 0 0 25 0 0 12 0 0 6 14 0
4RLP 0 20 16 3 24 0 0 8 0 0 3 0 0
4L43 0 0 19 0 24 0 0 0 0 11 11 8 0
4L44 0 0 21 0 30 0 0 0 0 7 13 7 0
3A60 0 20 0 0 27 0 4 0 0 2 22 2 0
4L3L 0 0 22 0 22 0 2 3 0 0 7 4 18
4L3J 0 0 21 0 25 0 6 3 2 0 6 5 0
4L45 0 0 19 0 27 0 0 0 5 0 10 3 0
3WF7 0 0 7 0 17 0 0 0 0 0 22 10 0
3WF5 0 0 0 0 22 0 2 0 0 4 8 11 0
3WE4 0 0 0 0 12 0 6 0 0 3 6 17 0