Back to basics: the untreated rabbit reticulocyte lysate as a competitive system to recapitulate cap/poly(A) synergy and the selective advantage of IRES-driven translation

Translation of most eukaryotic mRNAs involves the synergistic action between the 5′ cap structure and the 3′ poly(A) tail at the initiation step. The poly(A) tail has also been shown to stimulate translation of picornavirus internal ribosome entry sites (IRES)-directed translation. These effects hav...

Full description

Saved in:
Bibliographic Details
Published in:Nucleic acids research 2007-09, Vol.35 (18), p.e121-e121
Main Authors: Rifo, Ricardo Soto, Ricci, Emiliano P, Décimo, Didier, Moncorgé, Olivier, Ohlmann, Théophile
Format: Article
Language:English
Subjects:
Animals
Encephalomyocarditis virus - genetics
Foot-and-mouth disease virus
Globins - genetics
Hepatitis C virus
Methods Online
Models, Biological
Peptide Chain Initiation, Translational
Picornavirus
Poly A - metabolism
Polyadenylation
Rabbits
Reticulocytes - metabolism
RNA Caps - metabolism
RNA, Viral - chemistry
RNA-Binding Proteins
Citations: Items that cite this one
Online Access:Request full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Translation of most eukaryotic mRNAs involves the synergistic action between the 5′ cap structure and the 3′ poly(A) tail at the initiation step. The poly(A) tail has also been shown to stimulate translation of picornavirus internal ribosome entry sites (IRES)-directed translation. These effects have been attributed principally to interactions between eIF4G and poly(A)-binding protein (PABP) but also to the participation of PABP in other steps during translation initiation. As the rabbit reticulocyte lysate (RRL) does not recapitulate this cap/poly(A) synergy, several systems based on cellular cell-free extracts have been developed to study the effects of poly(A) tail in vitro but they generally exhibit low translational efficiency. Here, we describe that the non-nuclease-treated RRL (untreated RRL) is able to recapitulate the effects of poly(A) tail on translation in vitro. In this system, translation of a capped/polyadenylated RNA was specifically inhibited by either Paip2 or poly(rA), whereas translation directed by HCV IRES remained unaffected. Moreover, cleavage of eIF4G by FMDV L protease strongly stimulated translation directed by the EMCV IRES, thus recapitulating the competitive advantage that the proteolytic processing of eIF4G confers to IRES-driven RNAs.
ISSN:0305-1048
1362-4962
DOI:10.1093/nar/gkm682