Initiation at the third in-frame AUG codon of open reading frame 3 of the hepatitis E virus is essential for viral infectivity in vivo |
| |
| Authors: | Huang Y W Opriessnig T Halbur P G Meng X J |
| |
| Affiliation: | Center for Molecular Medicine and Infectious Diseases, Department of Biomedical Sciences and Pathobiology, Virginia Polytechnic Institute and State University, 1410 Price's Fork Road, Blacksburg, VA 24601, USA. |
| |
| Abstract: | To determine the initiation strategy of the hepatitis E virus (HEV) open reading frame 3 (ORF3), we constructed five HEV mutants with desired mutations in the ORF1 and ORF2 junction region and tested their levels of in vivo infectivity in pigs. A mutant with a C-terminally truncated ORF3 is noninfectious in pigs, indicating that an intact ORF3 is required for in vivo infectivity. Mutations with substitutions in the first in-frame AUG in the junction region or with the same T insertion at the corresponding position of HEV genotype 4 did not affect the virus infectivity or rescue, although mutations with combinations of the two affected virus recovery efficiency, and a single mutation at the third in-frame AUG completely abolished virus infectivity in vivo, indicating that the third in-frame AUG in the junction region is required for virus infection and is likely the authentic initiation site for ORF3. A conserved double stem-loop RNA structure, which may be important for HEV replication, was identified in the junction region. This represents the first report of using a unique homologous pig model system to study the molecular mechanism of HEV replication and to systematically and definitively identify the authentic ORF3 initiation site. |
| |
| Keywords: | |
| 本文献已被 PubMed 等数据库收录！ |
|
