Mutation of I176R in the E coding region weakens Japanese encephalitis virus neurovirulence, but not its growth rate in BHK-21 cells
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Previously, we isolated the Japanese encephalitis virus (JEV) strain SCYA201201. In this study, we passed the SCYA201201 strain in Syrian baby hamster kidney (BHK-21) cells 120 times to obtain the SCYA201201-0901 strain, which exhibited an attenuated phenotype in mice. Comparison of SCYA201201-0901 amino acid sequences with those of other JEV strains revealed a single mutation, I176R, in the E coding region. Using reverse genetic technology, we provide evidence that this single E-I176R mutation does not affect virus growth in BHK-21 cells but significantly decreases JEV neurovirulence in mice. This study provides critical information for understanding the molecular mechanism of JEV attenuation.
This work was supported by the National Program on Key Research Project of China (2016YFD0500403).
Compliance with ethical standards
Conflict of interest
The authors declare that there is no conflict of interest.
All animal experiments were approved by the Committee of the Ethics on Animal Care and Experiments at Sichuan Agricultural University. All experimental procedures were carried out in accordance with the approved guidelines.
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