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Updated: Aug 19, 2026

Development and Application of Rapamycin-regulated Tyrosine Phosphatases
06:56

Development and Application of Rapamycin-regulated Tyrosine Phosphatases

Published on: September 6, 2024

Signaling by target of rapamycin proteins in cell growth control

Ken Inoki1, Hongjiao Ouyang, Yong Li

  • 1Life Science Institute, University of Michigan Medical School, 5450 Medical Science I Bldg., Ann Arbor, MI 48109-0606, USA.

Microbiology and Molecular Biology Reviews : MMBR
|March 10, 2005
PubMed

Insights

The target of rapamycin (TOR) pathway controls cell growth by integrating various signals. Recent discoveries reveal TSC1-TSC2 and Rheb as key regulators in TOR signaling, advancing our understanding of cell growth control.

Area of Science:

  • Cellular Biology
  • Molecular Signaling
  • Biochemistry

Background:

  • Target of rapamycin (TOR) proteins are crucial regulators of cell growth, integrating signals from nutrients, growth factors, and energy status.
  • TOR signaling impacts cell growth through targets like ribosomal S6 kinase 1 (S6K) and eukaryotic initiation factor 4E binding protein 1 (4EBP1), affecting translational control.

Purpose of the Study:

  • To review the current understanding of target of rapamycin (TOR) signaling regulation.
  • To discuss the role of TOR as a signaling nexus controlling cell growth in normal development and tumorigenesis.

Main Methods:

  • Literature review of recent breakthroughs in TOR signaling research.
  • Analysis of the molecular mechanisms underlying TOR activation and regulation.

Main Results:

  • Identification of tuberous sclerosis complex (TSC1-TSC2) as negative regulators of TOR signaling.
  • Discovery of Rheb GTPase as a direct downstream target of TSC1-TSC2 and a positive regulator of TOR function.

Conclusions:

  • The TSC1-TSC2-Rheb pathway is a critical determinant of TOR activation.
  • Understanding TOR regulation provides insights into controlling cell growth during development and in diseases like cancer.

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