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Updated: Jul 23, 2025
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Detection of Small GTPase Prenylation and GTP Binding Using Membrane Fractionation and GTPase-linked Immunosorbent Assay
Published on: November 11, 2018
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RAS GTPases and Interleaflet Coupling in the Plasma Membrane.
Junchen Liu1, Neha Arora1, Yong Zhou2,3
1Department of Integrative Biology and Pharmacology, McGovern Medical School, University of Texas Health Science Center, Houston, Texas 77030, USA.
Cold Spring Harbor Perspectives in Biology
|July 18, 2023
Summary
RAS proteins, crucial in cancer, signal at the plasma membrane. This review explores how RAS-lipid interactions and interleaflet coupling influence cancer signaling and tumor microenvironments.
Area of Science:
- Molecular Cell Biology
- Cancer Biology
- Biophysics
Background:
- RAS genes are frequently mutated in various cancers.
- RAS proteins signal primarily from the inner leaflet of the plasma membrane (PM).
- Understanding the PM's unique environment is key to RAS function.
Purpose of the Study:
- To review RAS-lipid interactions at the plasma membrane.
- To explore interleaflet coupling mechanisms in RAS signaling.
- To understand how RAS integrates extracellular cues with intracellular signaling.
Main Methods:
- Superresolution imaging
- Molecular dynamic simulations
- Biophysical assays
Main Results:
- RAS proteins sort specific lipids and form signaling nanoclusters on the inner PM.
- RAS proteins sense and respond to components of the outer PM leaflet.
- Interleaflet coupling allows integration of extracellular and intracellular information.
Conclusions:
- RAS-lipid interactions and interleaflet coupling are critical for RAS signaling.
- Mutant RAS can modify tumor microenvironments through PM communication.
- Further research into PM communication mechanisms is warranted.
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