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Microscopy of Fission Yeast Sexual Lifecycle
07:47

Microscopy of Fission Yeast Sexual Lifecycle

Published on: March 9, 2016

TOR signaling in fission yeast

Yoko Otsubo1, Masayuki Yamamato

  • 1Department of Biophysics and Biochemistry, Graduate School of Science, University of Tokyo, Hongo, Tokyo, Japan.

Critical Reviews in Biochemistry and Molecular Biology
|August 30, 2008
PubMed

Insights

Fission yeast possesses two TOR kinases, Tor1 and Tor2, with distinct roles in cell cycle and development. This microbe offers a model for studying TOR signaling pathways, even though rapamycin has limited effects on its growth.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Yeast Genetics

Background:

  • Fission yeast, like higher eukaryotes, exhibits a TSC/Rheb/TOR signaling pathway.
  • Two distinct TOR complexes, TORC1 and TORC2, have been identified in fission yeast.
  • TORC1 contains Tor2, while TORC2 contains Tor1, suggesting specialized functions.

Purpose of the Study:

  • To investigate the opposing functions of fission yeast TORC1 and TORC2.
  • To explore the role of TOR signaling in G1 arrest and sexual development.
  • To understand the effects of rapamycin on fission yeast TOR pathways.

Main Methods:

  • Analysis of TORC1 and TORC2 composition and function.
  • Investigation of G1 arrest and sexual development pathways.
  • Detailed examination of rapamycin's effects on cellular functions.

Main Results:

  • Fission yeast TORC1 (containing Tor2) and TORC2 (containing Tor1) display opposing roles in promoting G1 arrest and sexual development.
  • Rapamycin does not inhibit wild-type fission yeast growth but impacts specific TOR-mediated cellular functions.
  • The identified TOR pathway components and their functions are conserved across eukaryotes.

Conclusions:

  • Fission yeast TORC1 and TORC2 have divergent functions in regulating cell cycle and development.
  • Despite resistance to growth inhibition, rapamycin reveals specific roles for TOR signaling in fission yeast.
  • Fission yeast serves as a valuable model organism for dissecting conserved TOR signaling pathways.

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