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Updated: Sep 28, 2026

Spatial and Temporal Analysis of Active ERK in the C. elegans Germline
08:40

Spatial and Temporal Analysis of Active ERK in the C. elegans Germline

Published on: November 29, 2016

Activation of ERK, controlled by Rac1 and Cdc42 via Akt, is required for anoikis

Wilfrid Rul1, Olivier Zugasti, Pierre Roux

  • 1Institut de Génétique Moléculaire, CNRS UMR5535, 1919 Route de Mende, F-34293 Montpellier Cedex 5, France.

Annals of the New York Academy of Sciences
|December 18, 2002
PubMed

Insights

Inhibiting Rac1 or Cdc42 signaling in fibroblasts triggers apoptosis, dependent on p53. This pathway involves MAPK ERK activation, with moderate levels promoting cell death and sustained levels promoting survival.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Cancer Research

Background:

  • Rho family GTPases, Rac1 and Cdc42, regulate cell survival.
  • Anchorage-dependent cell survival is crucial for tissue integrity.
  • Apoptosis, or programmed cell death, is a fundamental biological process.

Purpose of the Study:

  • To investigate the role of Rac1 and Cdc42 signaling in anoikis (anchorage-dependent cell death).
  • To elucidate the downstream signaling pathways involved in Rac1/Cdc42-induced apoptosis.
  • To determine the specific role of MAPK ERK activation in this process.

Main Methods:

  • Utilized murine fibroblasts (both immortalized and primary cells).
  • Inhibited Rac1 and Cdc42 signaling pathways.
  • Analyzed p53 activation and MAPK ERK pathway signaling (including PI(3)K, Akt, Raf, MEK, and Ras).

Main Results:

  • Inhibition of Rac1 or Cdc42 induced apoptosis, mimicking anchorage loss.
  • p53 tumor suppressor and its activation were essential for this cell death.
  • Rac1/Cdc42 inhibition activated the MAPK ERK pathway via PI(3)K, Akt, Raf, and MEK.
  • Moderate ERK activation was pro-apoptotic, while sustained ERK activation promoted survival.

Conclusions:

  • Rac1 and Cdc42 signaling are critical regulators of anchorage-dependent cell survival.
  • The p53 pathway and specific levels of ERK activation are key mediators of anoikis.
  • Understanding these pathways offers potential therapeutic targets for cancer treatment.

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