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Microscopy of Fission Yeast Sexual Lifecycle
07:47

Microscopy of Fission Yeast Sexual Lifecycle

Published on: March 9, 2016

Fission yeast tor1 functions in response to various stresses including nitrogen starvation, high osmolarity, and high

M Kawai1, A Nakashima, M Ueno

  • 1Department of Chemistry, Faculty of Science, Shizuoka University, 836 Oya, Shizuoka, 422-8529, Japan.

Current Genetics
|June 21, 2001
PubMed

Insights

The target of rapamycin (TOR) protein Tor1 is essential for sexual development and stress response in Schizosaccharomyces pombe. Tor1 regulates cell cycle progression under nitrogen starvation, impacting fertility and survival under various environmental stresses.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Genetics

Background:

  • Target of rapamycin (TOR) proteins are crucial kinases regulating cell growth based on nutrient availability.
  • Two TOR-related genes exist in Schizosaccharomyces pombe, but their functions remain uncharacterized.
  • Sexual development and stress responses are vital cellular processes influenced by nutrient and environmental cues.

Purpose of the Study:

  • To investigate the function of the Schizosaccharomyces pombe tor1+ gene.
  • To determine Tor1's role in sexual development and response to nutrient starvation.
  • To analyze Tor1's involvement in cellular stress resistance.

Main Methods:

  • Gene expression analysis of ste11+ in tor1- cells.
  • Cell cycle analysis under nitrogen starvation.
  • Phenotypic analysis of tor1- cells under various stress conditions (high pH, salt, sorbitol, temperature).
  • Sensitivity assays using rapamycin, fluphenazine, and cyclosporin A.

Main Results:

  • tor1+ is required for sexual development induced by nitrogen starvation.
  • tor1- cells fail to arrest at the G1 phase after nitrogen starvation, unlike wild-type cells.
  • tor1- cells exhibit impaired growth under diverse stress conditions, including osmotic, alkaline, and thermal stress.
  • tor1- cells are sensitive to rapamycin, fluphenazine, and cyclosporin A, indicating Tor1's role in drug sensitivity.

Conclusions:

  • Tor1 is essential for initiating sexual development in response to nitrogen starvation.
  • Tor1 plays a critical role in regulating cell cycle progression during nutrient deprivation.
  • Tor1 is indispensable for survival and growth under a broad spectrum of environmental stresses.
  • Tor1 function is linked to pathways involving calmodulin and calcineurin.

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