Pol IV and RDR2: A two-RNA-polymerase machine that produces double-stranded RNA.
Science
; 374(6575): 1579-1586, 2021 Dec 24.
Article
en En
| MEDLINE
| ID: mdl-34941388
ABSTRACT
DNA methylation affects gene expression and maintains genome integrity. The DNA-dependent RNA polymerase IV (Pol IV), together with the RNA-dependent RNA polymerase RDR2, produces double-stranded small interfering RNA precursors essential for establishing and maintaining DNA methylation in plants. We determined the cryoelectron microscopy structures of the Pol IVRDR2 holoenzyme and the backtracked transcription elongation complex. These structures reveal that Pol IV and RDR2 form a complex with their active sites connected by an interpolymerase channel, through which the Pol IVgenerated transcript is handed over to the RDR2 active site after being backtracked, where it is used as the template for double-stranded RNA (dsRNA) synthesis. Our results describe a 'backtracking-triggered RNA channeling' mechanism underlying dsRNA synthesis and also shed light on the evolutionary trajectory of eukaryotic RNA polymerases.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
ARN Polimerasas Dirigidas por ADN
/
ARN Polimerasa Dependiente del ARN
/
ARN Bicatenario
/
Arabidopsis
/
ARN de Planta
/
Proteínas de Arabidopsis
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Science
Año:
2021
Tipo del documento:
Article
País de afiliación:
China