Isolation, genomic and biological characterizations of a rhabdovirus from mandarin fish (Siniperca chuatsi)

In this study, a mandarin fish (Siniperca chuatsi) rhabdovirus (SCRV) S3 was isolated, purified, and identified from live mandarin fish collected from a commercial market. The full-length genome of S3 is 11,582 bp and has a 36 bp insertion in the 5’-UTR of the genome. The genome homology between S3 and the representative species in the genera of Perhabdovirus, Spriviviruses, and Novirhabdoviruses is 29.6% ∼ 31.0%, 25.7% ∼ 25.8, and 0.3% respectively. The cell tropism study showed that S3 could not only infect fish-derived cells but also mammalian and human-derived cells at 28 °C. However, S3 had no infectivity to all the tested cells at 37 °C. The temperature was an important barrier to the infection of SCRV S3. The upper limit of temperature for S3 growth in cells is 32 °C and the lowest measurable virus replication temperature is 10 °C. The optimum growth temperature is 28 °C. The animal study showed that SCRV S3 exhibited strong pathogenicity to zebrafish. Mortality in blue zebrafish (Danio rerio) and red zebrafish (Danio rerio) at 28 °C was 53% and 73%, respectively. Zebrafish can be used as an infection model for SCRV. This study will aid in understanding the biological characterizations of SCRV and has important guiding significance for the effective prevention and control strategies of SCRV.