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Strategies for Tracking Anastasis, A Cell Survival Phenomenon that Reverses Apoptosis
12:55

Strategies for Tracking Anastasis, A Cell Survival Phenomenon that Reverses Apoptosis

Published on: February 16, 2015

Ras signalling and apoptosis

J Downward1

  • 1Imperial Cancer Research Fund, London, UK. downward@icrf.icnet.uk

Current Opinion in Genetics & Development
|April 8, 1998
PubMed

Insights

Ras proteins can promote or prevent cell death (apoptosis) by controlling different pathways. Understanding these Ras protein effects is crucial for cell survival research.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Biochemistry

Background:

  • Ras proteins play a dual role in regulating apoptosis, with effects varying by cell type.
  • Ras controls multiple effector pathways, including PI3-kinase (survival) and Raf (survival inhibition).
  • Mechanisms underlying Ras's influence on apoptosis, particularly Raf's role, require further elucidation.

Purpose of the Study:

  • To investigate the complex mechanisms by which Ras proteins regulate apoptosis.
  • To clarify the specific roles of effector pathways like PI3-kinase and Raf in Ras-mediated apoptosis.
  • To understand how Ras activation influences cell survival and death signaling.

Main Methods:

  • Analysis of Ras protein activation and its downstream signaling.
  • Investigating the impact of PI3-kinase and Raf pathways on apoptosis.
  • Utilizing cell-based assays to monitor apoptosis regulation.
  • Examining the activation of PKB/Akt and NF-kappa B in response to Ras signaling.

Main Results:

  • Ras proteins can either promote or inhibit apoptosis, contingent on cellular context.
  • PI3-kinase activation by Ras leads to a survival signal via PKB/Akt.
  • Raf activation by Ras can contribute to the inhibition of survival pathways.
  • Ras signaling can protect cells from apoptosis through PKB/Akt or NF-kappa B activation.

Conclusions:

  • Ras proteins exert complex, context-dependent control over apoptosis.
  • Multiple Ras effector pathways, including PI3-kinase/PKB/Akt and Raf, are critical for this regulation.
  • Ras-mediated protection from apoptosis can occur via PI3-kinase/PKB/Akt or NF-kappa B activation pathways.

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