Target of rapamycin in yeast, TOR2, is an essential phosphatidylinositol kinase homolog required for G1 progression

Cell. 1993 May 7;73(3):585-96. doi: 10.1016/0092-8674(93)90144-f.

Abstract

The yeast TOR2 gene encodes an essential 282 kd phosphatidylinositol (PI) 3-kinase homolog. TOR2 is related to the catalytic subunit of bovine PI 3-kinase and to yeast VPS34, a vacuolar sorting protein also shown to have PI 3-kinase activity. The immunosuppressant rapamycin most likely acts by inhibiting PI kinase activity because TOR2 mutations confer resistance to rapamycin and because a TOR1 TOR2 double disruption (TOR1 is a nonessential TOR2 homolog) confers G1 arrest, as does rapamycin. Our results further suggest that 3-phosphorylated phosphoinositides, whose physiological significance has not been determined, are an important signal in cell cycle activation. In yeast, this signal may act in a signal transduction pathway similar to the interleukin-2 signal transduction pathway in T cells.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cattle
  • Cell Cycle / drug effects
  • Cell Cycle Proteins
  • Chromosome Mapping
  • Chromosomes, Fungal
  • Cloning, Molecular
  • DNA, Fungal / genetics
  • DNA, Fungal / isolation & purification
  • G1 Phase / drug effects
  • Genes, Fungal*
  • Genomic Library
  • Immunosuppressive Agents / pharmacology*
  • Molecular Sequence Data
  • Oligodeoxyribonucleotides
  • Phosphatidylinositol 3-Kinases
  • Phosphotransferases (Alcohol Group Acceptor)*
  • Phosphotransferases / genetics*
  • Phosphotransferases / metabolism*
  • Plasmids
  • Polyenes / pharmacology*
  • RNA, Fungal / genetics
  • RNA, Fungal / isolation & purification
  • Restriction Mapping
  • Saccharomyces cerevisiae / enzymology
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae Proteins
  • Sequence Deletion
  • Sequence Homology, Amino Acid
  • Sirolimus

Substances

  • Cell Cycle Proteins
  • DNA, Fungal
  • Immunosuppressive Agents
  • Oligodeoxyribonucleotides
  • Polyenes
  • RNA, Fungal
  • Saccharomyces cerevisiae Proteins
  • Phosphotransferases
  • Phosphatidylinositol 3-Kinases
  • Phosphotransferases (Alcohol Group Acceptor)
  • TOR2 protein, S cerevisiae
  • Sirolimus

Associated data

  • GENBANK/L33709
  • GENBANK/S60899
  • GENBANK/S60900
  • GENBANK/S60901
  • GENBANK/S60902
  • GENBANK/S60903
  • GENBANK/S60904
  • GENBANK/S60905
  • GENBANK/S60924
  • GENBANK/X71416