Structural basis of plp2-mediated cytoskeletal protein folding by TRiC/CCT.
Sci Adv
; 9(11): eade1207, 2023 03 17.
Article
em En
| MEDLINE
| ID: mdl-36921056
ABSTRACT
The cytoskeletal proteins tubulin and actin are the obligate substrates of TCP-1 ring complex/Chaperonin containing TCP-1 (TRiC/CCT), and their folding involves co-chaperone. Through cryo-electron microscopy analysis, we present a more complete picture of TRiC-assisted tubulin/actin folding along TRiC adenosine triphosphatase cycle, under the coordination of co-chaperone plp2. In the open S1/S2 states, plp2 and tubulin/actin engaged within opposite TRiC chambers. Notably, we captured an unprecedented TRiC-plp2-tubulin complex in the closed S3 state, engaged with a folded full-length ß-tubulin and loaded with a guanosine triphosphate, and a plp2 occupying opposite rings. Another closed S4 state revealed an actin in the intermediate folding state and a plp2. Accompanying TRiC ring closure, plp2 translocation could coordinate substrate translocation on the CCT6 hemisphere, facilitating substrate stabilization and folding. Our findings reveal the folding mechanism of the major cytoskeletal proteins tubulin/actin under the coordination of the biogenesis machinery TRiC and plp2 and extend our understanding of the links between cytoskeletal proteostasis and related human diseases.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tubulina (Proteína)
/
Actinas
/
Proteínas do Citoesqueleto
/
Proteínas com Domínio MARVEL
Limite:
Humans
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article