Initiation of protein synthesis by internal entry of ribosomes into the 5' nontranslated region of encephalomyocarditis virus RNA in vivo.
AUTOR(ES)
Jang, S K
RESUMO
Expression vectors that yield mono-, di-, and tricistronic mRNAs upon transfection of COS-1 cells were used to assess the influence of the 5' nontranslated regions (5'NTRs) on translation of reporter genes. A segment of the 5'NTR of encephalomyocarditis virus (EMCV) allowed translation of an adjacent downstream reporter gene (CAT) regardless of its position in the mRNAs. A deletion in the EMCV 5'NTR abolishes this effect. Poliovirus infection completely inhibits translation of the first cistron of a dicistronic mRNA that is preceded by the capped globin 5'NTR, whereas the second cistron preceded by the EMCV 5'NTR is still translated. We conclude that the EMCV 5'NTR contains an internal ribosomal entry site that allows cap-independent initiation of translation. mRNA containing the adenovirus tripartite leader is also resistant to inhibition of translation by poliovirus.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=248413Documentos Relacionados
- A segment of the 5' nontranslated region of encephalomyocarditis virus RNA directs internal entry of ribosomes during in vitro translation.
- Dual initiation sites of protein synthesis on foot-and-mouth disease virus RNA are selected following internal entry and scanning of ribosomes in vivo.
- In vitro characterization of an internal ribosomal entry site (IRES) present within the 5' nontranslated region of hepatitis A virus RNA: comparison with the IRES of encephalomyocarditis virus.
- RNA--protein interactions within the internal translation initiation region of encephalomyocarditis virus RNA.
- Internal entry of ribosomes is directed by the 5' noncoding region of classical swine fever virus and is dependent on the presence of an RNA pseudoknot upstream of the initiation codon.