Target of rapamycin (TOR): balancing the opposing forces of protein synthesis and degradation

Curr Opin Genet Dev. 1999 Feb;9(1):49-54. doi: 10.1016/s0959-437x(99)80007-0.


Mitogenic and nutritional signals must be integrated for a cell to grow. The target of rapamycin (TOR) is emerging as an effector for signals which indicate to the cell whether the external environment is conducive for growth. Use of the immunosuppressant rapamycin, a bacterial macrolide, has been instructive in identifying potential signaling components downstream of TOR, leading to the observation that both protein synthesis and turnover are under TOR control. The central issues concerning TOR are the identification of the proliferative and anti-proliferative signals which mediate its function and the mechanisms by which these signals are transduced to downstream molecules.

Publication types

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

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacology*
  • Cell Cycle Proteins
  • Drug Resistance
  • Fungal Proteins / genetics
  • Fungal Proteins / physiology
  • Humans
  • Mutation
  • Phosphatidylinositol 3-Kinases*
  • Phosphotransferases (Alcohol Group Acceptor) / genetics
  • Phosphotransferases (Alcohol Group Acceptor) / physiology*
  • Protein Kinases*
  • Proteins / drug effects
  • Proteins / metabolism
  • Saccharomyces cerevisiae Proteins*
  • Sirolimus / pharmacology*
  • TOR Serine-Threonine Kinases


  • Anti-Bacterial Agents
  • Cell Cycle Proteins
  • Fungal Proteins
  • Proteins
  • Saccharomyces cerevisiae Proteins
  • Protein Kinases
  • Phosphatidylinositol 3-Kinases
  • Phosphotransferases (Alcohol Group Acceptor)
  • MTOR protein, human
  • TOR Serine-Threonine Kinases
  • TOR1 protein, S cerevisiae
  • Sirolimus