RNase E searches for cleavage sites in RNA by linear diffusion: direct evidence from single-molecule FRET.
Nucleic Acids Res
; 52(11): 6674-6686, 2024 Jun 24.
Article
en En
| MEDLINE
| ID: mdl-38647084
ABSTRACT
The ability of obstacles in cellular transcripts to protect downstream but not upstream sites en masse from attack by RNase E has prompted the hypothesis that this mRNA-degrading endonuclease may scan 5'-monophosphorylated RNA linearly for cleavage sites, starting at the 5' end. However, despite its proposed regulatory importance, the migration of RNase E on RNA has never been directly observed. We have now used single-molecule FRET to monitor the dynamics of this homotetrameric enzyme on RNA. Our findings reveal that RNase E slides along unpaired regions of RNA without consuming a molecular source of energy such as ATP and that its forward progress can be impeded when it encounters a large structural discontinuity. This movement, which is bidirectional, occurs in discrete steps of variable length and requires an RNA ligand much longer than needed to occupy a single RNase E subunit. These results indicate that RNase E scans for cleavage sites by one-dimensional diffusion and suggest a possible molecular mechanism.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
ARN
/
Transferencia Resonante de Energía de Fluorescencia
/
Endorribonucleasas
Idioma:
En
Revista:
Nucleic Acids Res
Año:
2024
Tipo del documento:
Article
País de afiliación:
Estados Unidos