A single-particle analysis method for detecting membrane remodelling and curvature sensing

Area of Science:

• Cell Biology
• Biophysics
• Molecular Biology

Background:

• Cell membrane shape is critical for organelle function.
• Understanding protein-mediated membrane remodeling is essential.

Purpose of the Study:

• To develop a novel assay for detecting protein-induced membrane curvature preference and remodeling.
• To investigate protein interactions with membrane curvature at physiologically relevant concentrations.

Main Methods:

• Utilized free-floating liposomes to assess protein-membrane interactions.
• Measured curvature preference and membrane remodeling activities of various protein domains.

Main Results:

• Validated known curvature preferences of BAR domains.
• Discovered high-curvature preference for AKT PH and HRS FYVE domains.
• Confirmed membrane vesiculation by EPN1 ENTH domain and showed similar activity for PiCALM and Hip1R ANTH domains.
• Found endophilin N-BAR domain's curvature sensitivity inversely correlates with membrane charge, with helix deletion enhancing specificity.

Conclusions:

• The developed assay is a versatile tool for qualitative assessment of membrane curvature sensing and remodeling by proteins.
• Provides new insights into the mechanisms of protein-lipid interactions in membrane dynamics.