Gene interactions and pathways from curated databases and text-mining
J Biol Chem 2007, PMID: 17565979

P-Rex1 links mammalian target of rapamycin signaling to Rac activation and cell migration.

Hernández-Negrete, Ivette; Carretero-Ortega, Jorge; Rosenfeldt, Hans; Hernández-García, Ricardo; Calderón-Salinas, J Victor; Reyes-Cruz, Guadalupe; Gutkind, J Silvio; Vázquez-Prado, José

Polarized cell migration results from the transduction of extra-cellular cues promoting the activation of Rho GTPases with the intervention of multidomain proteins, including guanine exchange factors. P-Rex1 and P-Rex2 are Rac GEFs connecting Gbetagamma and phosphatidylinositol 3-kinase signaling to Rac activation. Their complex architecture suggests their regulation by protein-protein interactions. Novel mechanisms of activation of Rho GTPases are associated with mammalian target of rapamycin (mTOR), a serine/threonine kinase known as a central regulator of cell growth and proliferation. Recently, two independent multiprotein complexes containing mTOR have been described. mTORC1 links to the classical rapamycin-sensitive pathways relevant for protein synthesis; mTORC2 links to the activation of Rho GTPases and cytoskeletal events via undefined mechanisms. Here we demonstrate that P-Rex1 and P-Rex2 establish, through their tandem DEP domains, interactions with mTOR, suggesting their potential as effectors in the signaling of mTOR to Rac activation and cell migration. This possibility was consistent with the effect of dominant-negative constructs and short hairpin RNA-mediated knockdown of P-Rex1, which decreased mTOR-dependent leucine-induced activation of Rac and cell migration. Rapamycin, a widely used inhibitor of mTOR signaling, did not inhibit Rac activity and cell migration induced by leucine, indicating that P-Rex1, which we found associated to both mTOR complexes, is only active when in the mTORC2 complex. mTORC2 has been described as the catalytic complex that phosphorylates AKT/PKB at Ser-473 and elicits activation of Rho GTPases and cytoskeletal reorganization. Thus, P-Rex1 links mTOR signaling to Rac activation and cell migration.

Document information provided by NCBI PubMed

Text Mining Data

Rac → mTOR signaling: " Rapamycin, a widely used inhibitor of mTOR signaling , did not inhibit Rac activity and cell migration induced by leucine, indicating that P-Rex1, which we found associated to both mTOR complexes, is only active when in the mTORC2 complex "

Manually curated Databases

  • IRef Biogrid Interaction: RICTOR — MLST8 (physical association, affinity chromatography technology)
  • IRef Biogrid Interaction: RICTOR — MTOR (physical association, affinity chromatography technology)
  • IRef Biogrid Interaction: PREX2 — MTOR (physical association, affinity chromatography technology)
  • IRef Biogrid Interaction: MLST8 — RPTOR (physical association, affinity chromatography technology)
  • IRef Biogrid Interaction: RICTOR — PREX1 (physical association, affinity chromatography technology)
  • IRef Biogrid Interaction: PREX1 — RPTOR (physical association, affinity chromatography technology)
  • IRef Biogrid Interaction: RPTOR — MTOR (physical association, affinity chromatography technology)
  • IRef Biogrid Interaction: PREX1 — MTOR (direct interaction, two hybrid)
  • IRef Biogrid Interaction: PREX1 — MTOR (physical association, affinity chromatography technology)
  • IRef Intact Interaction: Complex of PREX1-MTOR-PREX1 (association, pull down)
  • IRef Intact Interaction: Complex of PREX1-RPTOR-MTOR (association, anti tag coimmunoprecipitation)
  • IRef Intact Interaction: PREX2 — MTOR (physical association, pull down)
  • IRef Intact Interaction: PREX1 — MTOR (physical association, pull down)
  • IRef Intact Interaction: PREX1 — MTOR (physical association, two hybrid)
  • IRef Intact Interaction: PREX1 — MTOR (direct interaction, pull down)
  • IRef Intact Interaction: PREX1 — MTOR (physical association, anti tag coimmunoprecipitation)
  • IRef Intact Interaction: PREX1 — MTOR (physical association, anti bait coimmunoprecipitation)
  • IRef Intact Interaction: Complex of MTOR-RICTOR-PREX1 (association, anti tag coimmunoprecipitation)
In total, 8 gene pairs are associated to this article in curated databases