Internal initiation of translation in retroviral vectors carrying picornavirus 5' nontranslated regions
- Resource Type
- Authors
- Mohammed A. Adam; N Ramesh; A D Miller; W R Osborne
- Source
- Journal of Virology. 65:4985-4990
- Subject
- Picornavirus
Adenosine Deaminase
Genetic Vectors
Immunology
Gene Expression
Regulatory Sequences, Nucleic Acid
Biology
Virus Replication
Microbiology
Dogs
Eukaryotic translation
Virology
Gene expression
Animals
Humans
Coding region
Vector (molecular biology)
Cloning, Molecular
Encephalomyocarditis virus
Peptide Chain Initiation, Translational
Gene
Cells, Cultured
Polyribonucleotide Nucleotidyltransferase
Genetics
Messenger RNA
Translation (biology)
biology.organism_classification
Cell biology
Poliovirus
Retroviridae
Insect Science
Research Article
- Language
- ISSN
- 1098-5514
0022-538X
Previous work has shown that picornavirus 5' nontranslated regions (NTRs) can initiate internal translation of downstream coding regions both in vitro and in transient in vivo assays. We have used 5' NTR sequences from encephalomyocarditis virus and poliovirus to construct retroviral vectors that are designed to express two proteins from a single mRNA. Inclusion of 5' NTR sequences did not adversely affect vector titer. Protein expression was studied with stable cell lines generated by vector infection of mouse NIH 3T3 cells and human and canine skin fibroblasts. Expression of a coding region in the downstream position was at levels from 25 to 100% of the same coding region in the upstream position. Expression of downstream coding regions in control vectors that did not contain the 5' NTR sequences was very low, in agreement with the predictions of the scanning model for eukaryotic translation. These experiments demonstrate coordinate expression of two coding regions from a single mRNA in stable cell lines and provide further support for the model of internal translation initiation by sequences in the 5' NTRs of picornaviruses.