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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
Summary
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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