Rhodospsin is a G-protein-coupled receptor that is responsible for vision in dim light. Light isomerizes the protein's retinal chromophore and triggers concerted movements of several transmembrane helices. Here, an approach involving mutant rhodopsins and infrared spectroscopy enabled changes in the electrostatic environment to be seen as rhodopsin proceeded along its activation pathway. Early conformational changes were observed that precede the well-known larger movements of the transmembrane helices.
- Shixin Ye
- Ekaterina Zaitseva
- Reiner Vogel
