Pressure modulation of Ras-membrane interactions and intervesicle transfer
Shobhna Kapoor1, Alexander Werkmüller, Roger S Goody
1Physical Chemistry I-Biophysical Chemistry, Faculty of Chemistry, TU Dortmund University, Otto-Hahn-Strasse 6, D-44227 Dortmund, Germany.
Journal of the American Chemical Society
|April 9, 2013
Summary
High hydrostatic pressure (HHP) affects N-Ras protein interactions with cell membranes. This study reveals pressure influences N-Ras membrane association, dissociation, and clustering, suggesting a role in mechanosensing.
Area of Science:
- Biophysics
- Cell Biology
- Molecular Signaling
Background:
- Plasma membrane proteins are exposed to mechanical stresses like high hydrostatic pressure (HHP).
- Small GTPases, such as Ras, are involved in pressure-sensitive signaling pathways.
- The precise impact of mechanical forces on biological processes remains largely unknown.
Purpose of the Study:
- To investigate the effects of HHP on the membrane association, dissociation, and transfer of N-Ras.
- To determine kinetic parameters and volumetric properties of N-Ras membrane interactions under pressure.
- To explore the potential of lipidated signaling molecules as mechanosensors.
Main Methods:
- Utilized a Förster Resonance Energy Transfer (FRET)-based assay.
- Quantified kinetic parameters and volumetric properties of N-Ras membrane processes.
- Examined N-Ras behavior in different lipid membrane compositions and organizations.
Main Results:
- HHP promotes the membrane association of N-Ras.
- HHP's effect on N-Ras dissociation varies with lipid membrane properties.
- HHP enhances N-Ras clustering, particularly in heterogeneous membranes.
Conclusions:
- Membrane-associated proteins like N-Ras are sensitive to mechanical pressure.
- Lipidated signaling molecules may act as mechanosensors, converting mechanical stimuli into chemical signals.
- Findings offer insights into pressure-regulated signaling in extreme environments like the deep sea.
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