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Complexity of the TOR signaling network

Ken Inoki1, Kun-Liang Guan

  • 1Life Sciences Institute, Department of Biological Chemistry, Institute of Gerontology, University of Michigan, Ann Arbor, MI 48109, USA.

Trends in Cell Biology
|March 7, 2006
PubMed

Insights

The target of rapamycin (TOR) pathway, a key regulator of cell growth, involves two distinct complexes (TORC1 and TORC2) with varied functions. New research reveals greater complexity in TOR signaling across species.

Area of Science:

  • Molecular Biology
  • Cellular Biology
  • Biochemistry

Background:

  • The target of rapamycin (TOR) is a highly conserved serine/threonine kinase.
  • TOR is a central regulator of cell growth, responding to diverse signals like nutrients and stress.
  • Two distinct TOR complexes, TORC1 and TORC2, have been identified with different substrates and functions.

Purpose of the Study:

  • To discuss recent findings on the complexity of TOR signaling.
  • To highlight the distinct roles of TORC1 and TORC2 in various organisms.
  • To provide an updated overview of TOR pathway regulation.

Main Methods:

  • Literature review of recent studies on TOR signaling.
  • Comparative analysis of TOR complex functions in yeast, flies, and mammals.
  • Synthesis of current knowledge on TOR pathway regulation and substrates.

Main Results:

  • TOR signaling is more complex than previously understood.
  • TORC1 and TORC2 exhibit distinct and crucial physiological roles.
  • TOR pathway regulation and function are conserved yet divergent across eukaryotes.

Conclusions:

  • The TOR pathway, through TORC1 and TORC2, plays a fundamental role in cell growth regulation.
  • Understanding TOR complex diversity is key to comprehending cellular responses to environmental cues.
  • Further research will continue to unravel the intricate mechanisms of TOR signaling.

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