mRNA structural dynamics shape Argonaute-target interactions.
Nat Struct Mol Biol
; 27(9): 790-801, 2020 09.
Article
en En
| MEDLINE
| ID: mdl-32661421
ABSTRACT
Small interfering RNAs (siRNAs) promote RNA degradation in a variety of processes and have important clinical applications. siRNAs direct cleavage of target RNAs by guiding Argonaute2 (AGO2) to its target site. Target site accessibility is critical for AGO2-target interactions, but how target site accessibility is controlled in vivo is poorly understood. Here, we use live-cell single-molecule imaging in human cells to determine rate constants of the AGO2 cleavage cycle in vivo. We find that the rate-limiting step in mRNA cleavage frequently involves unmasking of target sites by translating ribosomes. Target site masking is caused by heterogeneous intramolecular RNA-RNA interactions, which can conceal target sites for many minutes in the absence of translation. Our results uncover how dynamic changes in mRNA structure shape AGO2-target recognition, provide estimates of mRNA folding and unfolding rates in vivo, and provide experimental evidence for the role of mRNA structural dynamics in control of mRNA-protein interactions.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
ARN Mensajero
/
Proteínas Argonautas
Límite:
Humans
Idioma:
En
Revista:
Nat Struct Mol Biol
Asunto de la revista:
BIOLOGIA MOLECULAR
Año:
2020
Tipo del documento:
Article
País de afiliación:
Países Bajos