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Assessing cell size and cell cycle regulation in cells with altered TOR activity

Megan Cully1, Julian Downward

  • 1Signal Transduction Laboratory, Cancer Research UK London Research Institute, London, UK.

Methods in Molecular Biology (Clifton, N.J.)
|November 30, 2011
PubMed

Insights

Target of rapamycin (TOR) is a key regulator of cell growth. Researchers developed methods to measure cell size, providing an indirect way to assess TOR activity in cell cultures and Drosophila wings.

Area of Science:

  • Cellular Biology
  • Developmental Biology
  • Molecular Biology

Background:

  • The Target of Rapamycin (TOR) pathway is a central regulator of cell growth and organismal development.
  • TOR integrates numerous pro-growth and anti-growth signals, acting as a critical hub for cellular homeostasis.
  • Cell size serves as a reliable indirect indicator of TOR pathway activity.

Purpose of the Study:

  • To describe and validate methods for analyzing cell size.
  • To establish cell size as a readout for Target of Rapamycin (TOR) activity.
  • To demonstrate the applicability of these methods in both cell culture and in vivo models.

Main Methods:

  • Cell culture techniques for growing and maintaining cells.
  • Microscopy and image analysis for precise cell size measurements.
  • Analysis of cell size in the wing imaginal discs of Drosophila melanogaster.

Main Results:

  • Established robust protocols for quantifying cell size.
  • Demonstrated a correlation between cell size and TOR pathway status.
  • Successfully applied cell size analysis in both in vitro and in vivo systems.

Conclusions:

  • Cell size analysis is a practical and informative method for assessing TOR activity.
  • These methods facilitate the study of growth regulation in diverse biological contexts.
  • The described techniques can be widely adopted for research on cell growth and development.

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