DEAD-box protein DDX3 associates with eIF4F to promote translation of selected mRNAs.
EMBO J
; 31(18): 3745-56, 2012 Sep 12.
Article
em En
| MEDLINE
| ID: mdl-22872150
ABSTRACT
Here, we have characterized a step in translation initiation of viral and cellular mRNAs that contain RNA secondary structures immediately at the vicinity of their m(7)GTP cap. This is mediated by the DEAD-box helicase DDX3 which can directly bind to the 5' of the target mRNA where it clamps the entry of eIF4F through an eIF4G and Poly A-binding protein cytoplasmic 1 (PABP) double interaction. This could induce limited local strand separation of the secondary structure to allow 43S pre-initiation complex attachment to the 5' free extremity of the mRNA. We further demonstrate that the requirement for DDX3 is highly specific to some selected transcripts, cannot be replaced or substituted by eIF4A and is only needed in the very early steps of ribosome binding and prior to 43S ribosomal scanning. Altogether, these data define an unprecedented role for a DEAD-box RNA helicase in translation initiation.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Regulação da Expressão Gênica
/
Fator de Iniciação 4F em Eucariotos
/
RNA Helicases DEAD-box
Tipo de estudo:
Risk_factors_studies
Limite:
Humans
Idioma:
En
Revista:
EMBO J
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
França