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Updated: Feb 22, 2026
10:03
Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
18.5K
The form and function of channelrhodopsin.
Karl Deisseroth1,2,3, Peter Hegemann4,5
1Department of Bioengineering, Stanford University, Stanford, CA, USA. deissero@stanford.edu hegemann@rz.hu-berlin.de.
Science (New York, N.Y.)
|September 16, 2017
Summary
Channelrhodopsins are light-gated ion channels that help algae find optimal light. Research has advanced understanding of these proteins, enabling new optogenetic tools for neuroscience.
Area of Science:
- Biophysics
- Molecular Biology
- Optogenetics
Background:
- Channelrhodopsins are light-gated ion channels crucial for single-celled algae's phototaxis.
- Algal photobehavior, regulated by channelrhodopsins, has been studied for over 150 years.
Purpose of the Study:
- To elucidate the fundamental principles governing light-gated ion channel function.
- To explore the creation of novel channelrhodopsins with tailored properties for optogenetics.
Main Methods:
- Engineering channelrhodopsins with modified kinetics and spectral properties.
- Determining high-resolution crystal structures of channelrhodopsins.
- Utilizing structural models for protein redesign, focusing on ion selectivity.
Main Results:
- Demonstrated control over channelrhodopsin kinetics over several orders of magnitude.
- Identified and designed channelrhodopsins with altered light absorption spectra.
- Achieved redesign of channelrhodopsins for specific ion selectivity based on structural insights.
Conclusions:
- Advances in channelrhodopsin research reveal core mechanisms of light-gated ion channel operation.
- These engineered proteins serve as powerful optogenetic tools for investigating neural function.
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