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Updated: May 9, 2025
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Method to Visualize and Analyze Membrane Interacting Proteins by Transmission Electron Microscopy
Published on: March 5, 2017
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Asymmetric membrane properties through a protein lens.
Joseph H Lorent1, Angela Cabrera-Jojoa2,3, Kandice R Levental4
1Cellular and Molecular Pharmacology (FACM), Louvain Drug Research Institute, UCLouvain, Avenue Mounier 73/1, B-1200 Brussels, Belgium. joseph.lorent@uclouvain.be.
Faraday Discussions
|May 6, 2025
Summary
Transmembrane domains (TMDs) in cell membranes show specific structural adaptations to asymmetric lipid bilayers. These TMD properties can predict the characteristics of their surrounding membranes.
Area of Science:
- Biophysics
- Molecular Biology
- Cell Biology
Background:
- Plasma membranes exhibit lipid asymmetry, influencing transmembrane protein behavior.
- Single-pass transmembrane proteins (spTMPs) possess transmembrane domains (TMDs) adapted to membrane constraints.
Purpose of the Study:
- Analyze structural features of TMDs across life to understand their interaction with asymmetric membranes.
- Predict species-specific membrane properties based on TMD characteristics.
Main Methods:
- Comparative analysis of TMD structural features (ASA, hydrophobicity, aromaticity, charge) across diverse species.
- Molecular dynamics simulations of a representative spTMP in an asymmetric lipid bilayer.
Main Results:
- Eukaryotic plasma membrane TMDs show consistent asymmetries, while bacterial TMDs vary significantly.
- TMDs in eukaryotic Golgi and ER membranes exhibit inverted profiles compared to plasma membranes.
- Simulations revealed strong correlations between TMD hydrophobicity and acyl-chain density, and TMD charge and phosphate group density.
- Phospholipid unsaturation correlated with TMD phenylalanine location; membrane midplane showed hydrophobic residue accumulation.
Conclusions:
- TMD structural properties are complementary to the properties of their asymmetric lipid bilayers.
- TMD characteristics can serve as predictive indicators for the properties of their host membranes.
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