Molecular reconstruction of recurrent evolutionary switching in olfactory receptor specificity.
Elife
; 102021 10 22.
Article
en En
| MEDLINE
| ID: mdl-34677122
ABSTRACT
Olfactory receptor repertoires exhibit remarkable functional diversity, but how these proteins have evolved is poorly understood. Through analysis of extant and ancestrally reconstructed drosophilid olfactory receptors from the Ionotropic receptor (Ir) family, we investigated evolution of two organic acid-sensing receptors, Ir75a and Ir75b. Despite their low amino acid identity, we identify a common 'hotspot' in their ligand-binding pocket that has a major effect on changing the specificity of both Irs, as well as at least two distinct functional transitions in Ir75a during evolution. Moreover, we show that odor specificity is refined by changes in additional, receptor-specific sites, including those outside the ligand-binding pocket. Our work reveals how a core, common determinant of ligand-tuning acts within epistatic and allosteric networks of substitutions to lead to functional evolution of olfactory receptors.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Receptores Odorantes
/
Neuronas Receptoras Olfatorias
/
Evolución Molecular
/
Drosophila melanogaster
Límite:
Animals
Idioma:
En
Revista:
Elife
Año:
2021
Tipo del documento:
Article
País de afiliación:
Suiza