Characterization of two near-infrared genetically encoded voltage indicators

Area of Science:

• Neuroscience
• Optical Imaging
• Biotechnology

Background:

• Genetically encoded voltage indicators (GEVIs) are crucial for optical imaging of neuronal activity.
• Near-infrared (NIR) GEVIs offer advantages for in vivo mammalian brain monitoring.
• The availability and comprehensive evaluation of high-performing NIR GEVIs remain limited.

Purpose of the Study:

• To characterize and compare two recent NIR GEVIs, Archon1 and nirButterfly.
• To provide data supporting researchers in selecting appropriate NIR GEVIs for their specific applications.
• To assess the suitability of these GEVIs for population imaging.

Main Methods:

• Side-by-side characterization of Archon1 and nirButterfly.
• Evaluation of brightness, sensitivity, and kinetics.
• Assessment in a population imaging context.

Main Results:

• nirButterfly demonstrated seven-fold higher brightness than Archon1.
• nirButterfly exhibited faster kinetics compared to Archon1 for population imaging.
• Archon1 produced larger signal amplitudes than nirButterfly.

Conclusions:

• Neither Archon1 nor nirButterfly universally outperforms the other across all key parameters (brightness, kinetics, sensitivity).
• The choice between Archon1 and nirButterfly depends on specific experimental requirements.
• This comparative characterization offers valuable insights for future in vitro and ex vivo experimental designs using NIR GEVIs.