A topological switch in CFTR modulates channel activity and sensitivity to unfolding.
Nat Chem Biol
; 17(9): 989-997, 2021 09.
Article
en En
| MEDLINE
| ID: mdl-34341587
ABSTRACT
The cystic fibrosis transmembrane conductance regulator (CFTR) anion channel is essential to maintain fluid homeostasis in key organs. Functional impairment of CFTR due to mutations in the cftr gene leads to cystic fibrosis. Here, we show that the first nucleotide-binding domain (NBD1) of CFTR can spontaneously adopt an alternate conformation that departs from the canonical NBD fold previously observed. Crystallography reveals that this conformation involves a topological reorganization of NBD1. Single-molecule fluorescence resonance energy transfer microscopy shows that the equilibrium between the conformations is regulated by adenosine triphosphate binding. However, under destabilizing conditions, such as the disease-causing mutation F508del, this conformational flexibility enables unfolding of the ß-subdomain. Our data indicate that, in wild-type CFTR, this conformational transition of NBD1 regulates channel function, but, in the presence of the F508del mutation, it allows domain misfolding and subsequent protein degradation. Our work provides a framework to design conformation-specific therapeutics to prevent noxious transitions.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Regulador de Conductancia de Transmembrana de Fibrosis Quística
Tipo de estudio:
Diagnostic_studies
Límite:
Humans
Idioma:
En
Revista:
Nat Chem Biol
Asunto de la revista:
BIOLOGIA
/
QUIMICA
Año:
2021
Tipo del documento:
Article
País de afiliación:
Bélgica