Retinal degeneration in mice expressing the constitutively active G90D rhodopsin mutant.
Hum Mol Genet
; 29(6): 881-891, 2020 04 15.
Article
em En
| MEDLINE
| ID: mdl-31960909
ABSTRACT
Rhodopsin is the G protein-coupled receptor in rod photoreceptor cells that initiates vision upon photon capture. The light receptor is normally locked in an inactive state in the dark by the covalently bound inverse agonist 11-cis retinal. Mutations can render the receptor active even in the absence of light. This constitutive activity can desensitize rod photoreceptor cells and lead to night blindness. A G90D mutation in rhodopsin causes the receptor to be constitutively active and leads to congenital stationary night blindness, which is generally thought to be devoid of retinal degeneration. The constitutively active species responsible for the night blindness phenotype is unclear. Moreover, the classification as a stationary disease devoid of retinal degeneration is also misleading. A transgenic mouse model for congenital stationary night blindness that expresses the G90D rhodopsin mutant was examined to better understand the origin of constitutive activity and the potential for retinal degeneration. Heterozygous mice for the G90D mutation did not exhibit retinal degeneration whereas homozygous mice exhibited progressive retinal degeneration. Only a modest reversal of retinal degeneration was observed when transducin signaling was eliminated genetically, indicating that some of the retinal degeneration occurred in a transducin-independent manner. Biochemical studies on purified rhodopsin from mice indicated that multiple species can potentially contribute to the constitutive activity causing night blindness.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Degeneração Retiniana
/
Rodopsina
/
Transducina
/
Cegueira Noturna
/
Células Fotorreceptoras Retinianas Bastonetes
/
Mutação
Tipo de estudo:
Etiology_studies
Limite:
Animals
Idioma:
En
Revista:
Hum Mol Genet
Assunto da revista:
BIOLOGIA MOLECULAR
/
GENETICA MEDICA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Estados Unidos