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Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells
10:27

Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells

Published on: March 9, 2012

The Ras GDP/GTP cycle is regulated by oxidizing agents at the level of Ras regulators and effectors

K Accorsi1, C Giglione, M Vanoni

  • 1Groupe de Biophysique-Equipe 2, Ecole Polytechnique, Palaiseau, France.

FEBS Letters
|March 15, 2001
PubMed

Insights

Reactive oxygen species (ROS) can indirectly influence the Ras pathway by affecting regulators like GEF and GAP, and effectors such as c-Raf-1. This study investigates ROS actions on Ras pathway components.

Area of Science:

  • Cellular Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Reactive oxygen species (ROS) are crucial for cellular function and signal transduction.
  • The Ras pathway is a key signaling pathway implicated in various cellular processes.

Purpose of the Study:

  • To investigate the specific effects of ROS on the Ras signaling pathway.
  • To identify which components of the Ras pathway are modulated by ROS.

Main Methods:

  • Analysis of oxidizing agents' effects on Ras, GTPase activating protein (GAP), and nucleotide exchange factor (GEF) activities.
  • Investigation of ROS effects on H-Ras and its effector c-Raf-1 binding using scintillation proximity assay.

Main Results:

  • ROS did not affect the intrinsic activities of H-Ras or Ras2p.
  • ROS reversibly inhibited the actions of GEF and GAP on Ras, with inhibition extent varying by agent.
  • ROS inhibited the binding of c-Raf-1 to H-Ras.

Conclusions:

  • ROS can indirectly influence the Ras activation state by targeting its regulators and effectors.
  • GEF, GAP, and c-Raf-1 are potential targets for ROS action within the Ras pathway.

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