Visualizing the chaperone-mediated folding trajectory of the G protein ß5 ß-propeller.
Mol Cell
; 83(21): 3852-3868.e6, 2023 Nov 02.
Article
em En
| MEDLINE
| ID: mdl-37852256
ABSTRACT
The Chaperonin Containing Tailless polypeptide 1 (CCT) complex is an essential protein folding machine with a diverse clientele of substrates, including many proteins with ß-propeller domains. Here, we determine the structures of human CCT in complex with its accessory co-chaperone, phosducin-like protein 1 (PhLP1), in the process of folding Gß5, a component of Regulator of G protein Signaling (RGS) complexes. Cryoelectron microscopy (cryo-EM) and image processing reveal an ensemble of distinct snapshots that represent the folding trajectory of Gß5 from an unfolded molten globule to a fully folded ß-propeller. These structures reveal the mechanism by which CCT directs Gß5 folding through initiating specific intermolecular contacts that facilitate the sequential folding of individual ß sheets until the propeller closes into its native structure. This work directly visualizes chaperone-mediated protein folding and establishes that CCT orchestrates folding by stabilizing intermediates through interactions with surface residues that permit the hydrophobic core to coalesce into its folded state.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Chaperonas Moleculares
/
Proteínas de Ligação ao GTP
Limite:
Humans
Idioma:
En
Revista:
Mol Cell
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Estados Unidos