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MAPKAP1

Function

Subunit of mTORC2, which regulates cell growth and survival in response to hormonal signals. mTORC2 is activated by growth factors, but, in contrast to mTORC1, seems to be nutrient-insensitive. mTORC2 seems to function upstream of Rho GTPases to regulate the actin cytoskeleton, probably by activating one or more Rho-type guanine nucleotide exchange factors. mTORC2 promotes the serum-induced formation of stress-fibers or F-actin. mTORC2 plays a critical role in AKT1 'Ser-473' phosphorylation, which may facilitate the phosphorylation of the activation loop of AKT1 on 'Thr-308' by PDK1 which is a prerequisite for full activation. mTORC2 regulates the phosphorylation of SGK1 at 'Ser-422'. mTORC2 also modulates the phosphorylation of PRKCA on 'Ser-657'. Within mTORC2, MAPKAP1 is required for complex formation and mTORC2 kinase activity. MAPKAP1 inhibits MAP3K2 by preventing its dimerization and autophosphorylation. Inhibits HRAS and KRAS signaling. Enhances osmotic stress-induced phosphorylation of ATF2 and ATF2-mediated transcription. Involved in ciliogenesis, regulates cilia length through its interaction with CCDC28B independently of mTORC2 complex.

Sequence similarities

Belongs to the SIN1 family.

Tissue specificity

Ubiquitously expressed, with highest levels in heart and skeletal muscle.

Cellular localization

  • Cell membrane
  • Peripheral membrane protein
  • Cytoplasmic vesicle
  • Nucleus

Alternative names

  • Target of rapamycin complex 2 subunit MAPKAP1
  • TORC2 subunit MAPKAP1
  • Mitogen-activated protein kinase 2-associated protein 1
  • Stress-activated map kinase-interacting protein 1
  • SAPK-interacting protein 1
  • mSIN1
  • MAPKAP1
  • SIN1
  • MIP1

Target type

Proteins

Molecular weight

59123Da