DNA Origami Voltage Sensors for Transmembrane Potentials with Single-Molecule Sensitivity

Area of Science:

• Biotechnology and Nanotechnology
• Molecular and Cellular Biology
• Biophysics

Background:

• Neuronal signal transmission involves transmembrane potential changes.
• Existing methods for monitoring membrane potential include optical dyes and genetically encoded indicators.
• There is a need for alternative, non-genetic voltage sensing technologies.

Purpose of the Study:

• To present a DNA nanotechnology-based system for sensing transmembrane potential.
• To demonstrate the functionality of this system on liposomes.
• To modularly incorporate and optimize membrane targeting and voltage sensing capabilities.

Main Methods:

• Utilized DNA origami to construct the nanostructure.
• Incorporated a hydrophobic red dye as a membrane anchor and an anionic green dye as a sensing unit.
• Measured voltage-induced displacement via fluorescence resonance energy transfer (FRET) changes.

Main Results:

• Successfully demonstrated functionality on liposomes.
• Observed a FRET change of approximately 5% for a transmembrane potential change of 100 mV.
• Molecular dynamics simulations supported the sensor's working mechanism.

Conclusions:

• The developed DNA nanotechnology system effectively senses transmembrane potential changes.
• This approach offers a modular and non-genetically encoded alternative for membrane sensing.
• The system shows potential for future applications in studying cellular electrophysiology.