Using DNA origami to study nanoscale organization of plasma membranes

Area of Science:

• Cellular Biology
• Biophysics
• Nanotechnology

Background:

• Plasma membrane (PM) nanodomains are crucial for cellular processes but difficult to study due to their small size and instability.
• Existing super-resolution microscopy and single particle tracking methods face limitations in resolving nanodomain dynamics in living cells.

Purpose of the Study:

• To develop a novel method for investigating the architecture and dynamics of plasma membrane nanodomains in living cells.
• To utilize DNA origami probes with precisely controlled lipid anchors for nanoscale membrane surface sampling.

Main Methods:

• Fabrication of fluorescent DNA origami probes with tunable lipid anchors for insertion into the plasma membrane.
• Single particle tracking of DNA origami probes to analyze their diffusion and infer nanodomain organization.
• Investigating the role of actin cytoskeleton and mechanical forces on nanodomain stability and probe mobility.

Main Results:

• Stable immobilization of DNA origami probes requires interaction with multiple nanodomains, indicating dense nanodomain packing.
• PM nanodomains are smaller than 20 nm and their stability is influenced by the actin cytoskeleton.
• Mechanical stretching reversibly alters nanodomain organization and probe mobility, highlighting mechanotransduction roles.

Conclusions:

• The DNA origami probe approach offers a powerful tool for mapping nanoscale membrane architecture and dynamics in living cells.
• This method provides mechanistic insights into how cells regulate PM nanodomain organization in response to biochemical and mechanical cues.
• The study reveals the dynamic nature and mechanical sensitivity of plasma membrane nanodomains.