Amino acid residue at position 188 determines the UV-sensitive bistable property of vertebrate non-visual opsin Opn5.
Commun Biol
; 5(1): 63, 2022 01 18.
Article
em En
| MEDLINE
| ID: mdl-35042952
ABSTRACT
Opsins are G protein-coupled receptors specialized for photoreception in animals. Opn5 is categorized in an independent opsin group and functions for various non-visual photoreceptions. Among vertebrate Opn5 subgroups (Opn5m, Opn5L1 and Opn5L2), Opn5m and Opn5L2 bind 11-cis retinal to form a UV-sensitive resting state, which is inter-convertible with the all-trans retinal bound active state by photoreception. Thus, these opsins are characterized as bistable opsins. To assess the molecular basis of the UV-sensitive bistable property, we introduced comprehensive mutations at Thr188, which is well conserved among these opsins. The mutations in Opn5m drastically hampered 11-cis retinal incorporation and the bistable photoreaction. Moreover, T188C mutant Opn5m exclusively bound all-trans retinal and thermally self-regenerated to the original form after photoreception, which is similar to the photocyclic property of Opn5L1 bearing Cys188. Therefore, the residue at position 188 underlies the UV-sensitive bistable property of Opn5m and contributes to the diversification of vertebrate Opn5 subgroups.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Raios Ultravioleta
/
Proteínas de Xenopus
/
Opsinas
/
Aminoácidos
/
Proteínas de Membrana
Tipo de estudo:
Diagnostic_studies
Limite:
Animals
Idioma:
En
Revista:
Commun Biol
Ano de publicação:
2022
Tipo de documento:
Article