TOR Complexes and the Maintenance of Cellular Homeostasis

Trends Cell Biol. 2016 Feb;26(2):148-159. doi: 10.1016/j.tcb.2015.10.003. Epub 2015 Nov 4.

Abstract

The Target of Rapamycin (TOR) is a conserved serine/threonine (ser/thr) kinase that functions in two, distinct, multiprotein complexes called TORC1 and TORC2. Each complex regulates different aspects of eukaryote growth: TORC1 regulates cell volume and/or mass by influencing protein synthesis and turnover, while TORC2, as detailed in this review, regulates cell surface area by influencing lipid production and intracellular turgor. TOR complexes function in feedback loops, implying that downstream effectors are also likely to be involved in upstream regulation. In this regard, the notion that TORCs function primarily as mediators of cellular and organismal homeostasis is fundamentally different from the current, predominate view of TOR as a direct transducer of extracellular biotic and abiotic signals.

Keywords: Target Of Rapamycin (TOR); eisosome; growth; homeostasis; membrane tension; osmotic control; sphingolipid.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Cell Physiological Phenomena*
  • Cell Size
  • Homeostasis* / genetics
  • Humans
  • Lipid Metabolism / physiology
  • Mechanistic Target of Rapamycin Complex 1
  • Mechanistic Target of Rapamycin Complex 2
  • Multiprotein Complexes / physiology*
  • TOR Serine-Threonine Kinases / physiology*
  • Yeasts

Substances

  • Multiprotein Complexes
  • TOR Serine-Threonine Kinases
  • Mechanistic Target of Rapamycin Complex 1
  • Mechanistic Target of Rapamycin Complex 2