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Small noncoding RNA modulates Japanese encephalitis virus replication and translation in trans
Yi-Hsin Fan1, Muthukumar Nadar, Chiu-Chin Chen
1Department of Life Science and Institute of Biotechnology, National Dong Hwa University, Hualien 97401, Taiwan.
Virology Journal
|November 2, 2011
Summary
The Japanese encephalitis virus (JEV) small subgenomic flaviviral RNA (sfRNA) inhibits viral translation and replication. This study reveals sfRNA
Area of Science:
- Virology
- Molecular Biology
- RNA Biology
Background:
- The 3'-untranslated region (UTR) of Japanese encephalitis virus (JEV) contains sequence and structural elements crucial for regulating viral translation and replication.
- Small subgenomic flaviviral RNA (sfRNA), derived from conserved 3'-UTR regions, accumulates in JEV-infected cells, but its function remains unelucidated.
Purpose of the Study:
- To investigate the functional role of sfRNA in the Japanese encephalitis virus life cycle.
- To determine the impact of sfRNA on viral translation and replication processes.
Main Methods:
- Northern blot and real-time RT-PCR were employed to analyze sfRNA accumulation kinetics relative to viral antigenome synthesis.
- Functional assays involved transfecting cells with sfRNA to assess its effects on antigenome levels and viral translation using reporter mRNA systems.
Main Results:
- sfRNA accumulation coincided with the plateau of minus-strand RNA (antigenome) synthesis, suggesting a regulatory role.
- Transfection of sfRNA inhibited antigenome synthesis, indicating a negative feedback mechanism.
- Both in vivo and in vitro experiments demonstrated that sfRNA significantly suppresses JEV translation.
Conclusions:
- Small subgenomic flaviviral RNA (sfRNA) acts in trans to modulate both viral translation and replication.
- sfRNA plays a critical role in regulating the JEV life cycle by inhibiting key viral processes.
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