New Continuum Approaches for Determining Protein-Induced Membrane Deformations.

Area of Science:

• Biophysics
• Computational Biology
• Membrane Protein Dynamics

Background:

• Transmembrane proteins influence and are influenced by lipid bilayers, affecting biological processes like ion channel gating and membrane shape.
• Continuum elastic models are computationally efficient for studying protein-membrane interactions but often fail to reproduce atomistic simulation details.
• Accurate protein representation is key to improving continuum model predictions of membrane distortions.

Purpose of the Study:

• To develop and validate a hybrid continuum-atomistic model for simulating protein-membrane interactions.
• To assess the model's accuracy against fully atomistic simulations for ion channels.
• To investigate the role of membrane bending in the function of TRPV1 channels.

Main Methods:

• Development of a hybrid model coupling continuum membrane mechanics with atomistic protein representation.
• Validation using simulations of gramicidin in a POPC membrane.
• Application to study membrane deformation around TRPV1 voltage sensors.

Main Results:

• The hybrid model accurately reproduces membrane distortions and protein orientation observed in atomistic simulations.
• Calculations show excellent agreement with gramicidin-channel/POPC-membrane simulations.
• Membrane bending around TRPV1 voltage sensors significantly stabilizes channel insertion by exposing charged residues.

Conclusions:

• Hybrid continuum-atomistic models offer a computationally efficient and accurate approach for studying protein-membrane dynamics.
• The model successfully captures complex membrane deformations induced by transmembrane proteins.
• Membrane bending plays a critical role in the stability and function of ion channels like TRPV1.