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Updated: Jun 29, 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
Rhodopsin: structural basis of molecular physiology
1Howard Hughes Medical Institute, Laboratory of Molecular Biology and Biochemistry, The Rockefeller University, New York, New York 10021, USA.
Physiological Reviews
|October 3, 2001
Summary
The crystal structure of rhodopsin reveals unique protein-chromophore interactions and structural features. This provides insights into the visual system
Area of Science:
- Structural biology
- Biochemistry
- Neuroscience
Background:
- The structure of rod cell visual pigment rhodopsin was recently solved at 2.8-A resolution.
- A decade of structure-function studies on rhodopsin can now be critically evaluated.
- The structural basis for unique vertebrate visual system properties can be explored.
Purpose of the Study:
- To provide a critical evaluation of rhodopsin structure-function studies.
- To explain the structural basis for unique physiological properties of the vertebrate visual system.
- To support the helix movement model of receptor activation for G protein-coupled receptors (GPCRs).
Main Methods:
- X-ray crystallography at 2.8-A resolution.
- Analysis of chromophore-protein interactions.
- Evaluation of mutagenesis and spectroscopic studies.
Main Results:
- Rhodopsin's ligand-binding pocket is compact with unpredicted chromophore-protein interactions.
- Transmembrane helices exhibit interruptions and kinks, stabilized by interhelical interactions.
- Structural elements support the helix movement model for GPCR activation.
Conclusions:
- The rhodopsin structure provides a basis for understanding visual system physiology.
- The cytoplasmic domain structure suggests a one-to-one complex with transducin.
- Future studies will elucidate GPCR-mediated signal transduction mechanisms.
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