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Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells
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Target of rapamycin (TOR): balancing the opposing forces of protein synthesis and degradation

P B Dennis1, S Fumagalli, G Thomas

  • 1Friedrich Miescher Institute, Maulbeerstrasse 66, CH-4058, Basel, Switzerland.

Current Opinion in Genetics & Development
|March 11, 1999
PubMed

Insights

Cellular growth requires integrating signals, with the target of rapamycin (TOR) pathway mediating environmental cues. Rapamycin studies reveal TOR controls protein synthesis and turnover, highlighting key research questions on its upstream signals and downstream mechanisms.

Area of Science:

  • Cell Biology
  • Molecular Signaling
  • Biochemistry

Background:

  • Cellular growth depends on integrating mitogenic and nutritional signals.
  • The target of rapamycin (TOR) pathway is a key mediator of environmental cues for cell growth.
  • Rapamycin, an immunosuppressant, has been instrumental in dissecting TOR signaling.

Purpose of the Study:

  • To elucidate the role of the target of rapamycin (TOR) pathway in integrating growth signals.
  • To identify signaling components downstream of TOR.
  • To understand the mechanisms of TOR-mediated control over protein synthesis and turnover.

Main Methods:

  • Utilizing the immunosuppressant rapamycin to probe TOR signaling.
  • Investigating downstream effectors of TOR.
  • Analyzing changes in protein synthesis and turnover.

Main Results:

  • Identified downstream signaling components influenced by TOR.
  • Demonstrated that both protein synthesis and protein turnover are regulated by TOR.
  • Established TOR as a central regulator integrating growth-promoting signals.

Conclusions:

  • The TOR pathway is crucial for cellular decision-making regarding growth based on environmental conditions.
  • Further research is needed to identify specific proliferative and anti-proliferative signals upstream of TOR.
  • Understanding TOR signal transduction is key to comprehending cell growth regulation.

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