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Nitrogen Cavitation and Differential Centrifugation Allows for Monitoring the Distribution of Peripheral Membrane Proteins in Cultured Cells
Published on: August 18, 2017
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Ras and the Plasma Membrane: A Complicated Relationship.
Yong Zhou1, Priyanka Prakash1, Alemayehu A Gorfe1
1Department of Integrative Biology and Pharmacology, University of Texas Health Science Center at Houston, Houston, Texas 77030.
Cold Spring Harbor Perspectives in Medicine
|December 13, 2017
Summary
Ras proteins form distinct nanoclusters on the plasma membrane, crucial for cell signaling. Their assembly depends on G-domain interactions and membrane lipids, offering new ways to regulate signaling pathways.
Area of Science:
- Molecular Biology
- Cell Signaling
- Biophysics
Background:
- Ras signal transduction primarily occurs at the plasma membrane (PM).
- Ras isoforms (H-, N-, K-Ras) segregate into distinct nanoclusters on the PM.
- Spatial segregation into GTP-bound and GDP-bound nanoclusters is critical for effector activation.
Purpose of the Study:
- To elucidate the mechanisms underlying Ras nanocluster assembly.
- To understand the role of the Ras G-domain and membrane lipids in nanoclustering.
- To identify novel regulatory mechanisms for Ras signaling gain.
Main Methods:
- Analysis of Ras carboxy-terminal membrane anchor lipid-sorting specificity.
- Investigating Ras G-domain conformational changes upon guanine nucleotide binding.
- Studying Ras homodimerization as a prerequisite for nanoclustering.
Main Results:
- Ras nanoclusters exhibit distinct lipid compositions due to membrane anchor specificity.
- Ras G-domain conformation changes influence membrane anchor interactions.
- Ras G-domain homodimerization is essential for nanocluster formation.
Conclusions:
- Ras nanoclustering is regulated by G-domain interactions with the membrane anchor and lipid composition.
- Modulating Ras dimerization, PM lipid composition, or phospholipid dynamics can tune Ras signaling.
- These findings offer novel therapeutic targets for regulating Ras signaling.
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