Title:
|
Human blue cone opsin regeneration involves secondary retinal binding with analog specificity
|
Author:
|
Srinivasan, Sundaramoorthy; Fernández Sampedro, Miguel Ángel; Morillo Cazorla, Margarita; Ramon Portés, Eva; Jiménez Rosés, Mireia; Cordomi, Arnau; Garriga Solé, Pere
|
Other authors:
|
Universitat Politècnica de Catalunya. Departament d'Enginyeria Química; Universitat Politècnica de Catalunya. GBMI - Grup de Biotecnologia Molecular i Industrial |
Abstract:
|
Human color vision is mediated by the red, green, and blue cone visual pigments. Cone opsins are G-protein-coupled receptors consisting of an opsin apoprotein covalently linked to the 11-cis-retinal chromophore. All visual pigments share a common evolutionary origin, and red and green cone opsins exhibit a higher homology, whereas blue cone opsin shows more resemblance to the dim light receptor rhodopsin. Here we show that chromophore regeneration in photoactivated blue cone opsin exhibits intermediate transient conformations and a secondary retinoid binding event with slower binding kinetics. We also detected a fine-tuning of the conformational change in the photoactivated blue cone opsin binding site that alters the retinal isomer binding specificity. Furthermore, the molecular models of active and inactive blue cone opsins show specific molecular interactions in the retinal binding site that are not present in other opsins. These findings highlight the differential conformational versatility of human cone opsin pigments in the chromophore regeneration process, particularly compared to rhodopsin, and point to relevant functional, unexpected roles other than spectral tuning for the cone visual pigments |
Abstract:
|
Peer Reviewed |
Subject(s):
|
-Àrees temàtiques de la UPC::Ciències de la visió::Biologia ocular -Color vision -G proteins -- Receptors -Ligands (Biochemistry) -Color vision -G protein-coupled receptor -Retinoid -Ligand binding -Allostery -Spectroscopy -Proteïnes G -- Receptors -Sentit del color -Lligands (Bioquímica) |
Rights:
|
Attribution-NonCommercial-NoDerivs 3.0 Spain
http://creativecommons.org/licenses/by-nc-nd/3.0/es/ |
Document type:
|
Article - Submitted version Article |
Share:
|
|