The CRL4DCAF1 cullin-RING ubiquitin ligase is activated following a switch in oligomerization state.
EMBO J
; 40(22): e108008, 2021 11 15.
Article
en En
| MEDLINE
| ID: mdl-34595758
The cullin-4-based RING-type (CRL4) family of E3 ubiquitin ligases functions together with dedicated substrate receptors. Out of the Ë29 CRL4 substrate receptors reported, the DDB1- and CUL4-associated factor 1 (DCAF1) is essential for cellular survival and growth, and its deregulation has been implicated in tumorigenesis. We carried out biochemical and structural studies to examine the structure and mechanism of the CRL4DCAF1 ligase. In the 8.4 Å cryo-EM map of CRL4DCAF1 , four CUL4-RBX1-DDB1-DCAF1 protomers are organized into two dimeric sub-assemblies. In this arrangement, the WD40 domain of DCAF1 mediates binding with the cullin C-terminal domain (CTD) and the RBX1 subunit of a neighboring CRL4DCAF1 protomer. This renders RBX1, the catalytic subunit of the ligase, inaccessible to the E2 ubiquitin-conjugating enzymes. Upon CRL4DCAF1 activation by neddylation, the interaction between the cullin CTD and the neighboring DCAF1 protomer is broken, and the complex assumes an active dimeric conformation. Accordingly, a tetramerization-deficient CRL4DCAF1 mutant has higher ubiquitin ligase activity compared to the wild-type. This study identifies a novel mechanism by which unneddylated and substrate-free CUL4 ligases can be maintained in an inactive state.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas Serina-Treonina Quinasas
/
Ubiquitina-Proteína Ligasas
Tipo de estudio:
Prognostic_studies
Límite:
Humans
Idioma:
En
Revista:
EMBO J
Año:
2021
Tipo del documento:
Article
País de afiliación:
Suiza
Pais de publicación:
Reino Unido