Evaluating the mTOR Pathway in Physiological and Pharmacological Settings

Methods Enzymol. 2017:587:405-428. doi: 10.1016/bs.mie.2016.09.068. Epub 2016 Nov 9.

Abstract

Mammalian/mechanistic target of rapamycin (mTOR) is an evolutionarily conserved genuine protein kinase, which phosphorylates serine/threonine in response to growth factors and nutrients. It functions as a catalytic core in two distinct multiprotein complexes: mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). mTORC1 promotes cell growth and proliferation by positively regulating translation, transcription, and lipid biosynthesis in response to growth factors and amino acids, whereas it inhibits autophagy, an essential degradation and recycling pathway. mTORC2 regulates cell survival and cytoskeleton organization. Mechanistic insights into the function and regulation of mTOR complexes have been provided in various experimental settings and monitoring mTOR activity has been a most valuable way to judge whether levels of environmental cues such nutrients and growth factors can satisfy cellular needs for cell growth, proliferation, and autophagic response. Here, we describe useful methods to access mTOR activity in different experimental settings.

Keywords: Autophagy; Rag; Rapamycin; Rheb; TSC; Translation; mTOR; mTORC1; mTORC2.

MeSH terms

  • Animals
  • Autophagy
  • Autophagy-Related Protein-1 Homolog / metabolism
  • Blotting, Western / methods*
  • Cell Culture Techniques
  • Fluorescent Antibody Technique / methods
  • Humans
  • Immunoprecipitation / methods*
  • Mechanistic Target of Rapamycin Complex 1
  • Mechanistic Target of Rapamycin Complex 2
  • Monomeric GTP-Binding Proteins / metabolism
  • Multiprotein Complexes / metabolism
  • Neuropeptides / metabolism
  • Phosphorylation
  • Ras Homolog Enriched in Brain Protein
  • Signal Transduction
  • TOR Serine-Threonine Kinases / analysis
  • TOR Serine-Threonine Kinases / genetics
  • TOR Serine-Threonine Kinases / immunology
  • TOR Serine-Threonine Kinases / metabolism*
  • Transfection / methods*

Substances

  • Multiprotein Complexes
  • Neuropeptides
  • RHEB protein, human
  • Ras Homolog Enriched in Brain Protein
  • MTOR protein, human
  • Autophagy-Related Protein-1 Homolog
  • Mechanistic Target of Rapamycin Complex 1
  • Mechanistic Target of Rapamycin Complex 2
  • TOR Serine-Threonine Kinases
  • Monomeric GTP-Binding Proteins