Development of a reverse genetics system for Japanese encephalitis virus strain SA14-14-2
Japanese encephalitis virus SA14-14-2 (JEV SA14-14-2) is a widely used vaccine in China and other southeastern countries to prevent Japanese encephalitis in children. In this study, a stable infectious cDNA clone of JEV SA14-14-2 with a low copy number pACYC177 vector dependent on the T7 promoter and T7 terminator was developed. Two introns were inserted into the capsid gene and envelope gene of JEV cDNA for gene stability. Hepatitis delta virus ribozyme (HDVr) was engineered into the 3′ UTR cDNA of JEV for authentic 3′ UTR transcription. The rescued virus showed biological properties indistinguishable from those of the parent strain (JEV SA14-14-2). The establishment of a JEV SA14-14-2 reverse genetics system lays the foundation for the further development of other flavivirus vaccines and viral pathogenesis studies.
KeywordsJapanese encephalitis virus Infectious clone Intron T7 terminator
This work was supported by the National Key Research and Development Program of China (Grant No. 2016YFD0500400).
XX, HW, YG, SY, and BZ conceived and designed the experiments. GL, HJ, XN, YZ, NF, ZC, ST, WG, FY, LL, YZ, ZC, and NL performed the experiments and provided experiments materials or ideas.
Compliance with ethical standards
Conflict of interest
The authors have no conflict of interest to declare.
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