Recovery of Siniperca chuatsi rhabdovirus from cloned cDNA

Siniperca chuatsi rhabdovirus (SCRV) is an important pathogen that infects mandarin fish. A reverse genetics system is an important technical platform for virus research. In this study, the minigenome in which the enhanced green fluorescent protein gene is flanked by the viral genomic ends of SCRV and transcribed using a T7 promoter-terminator cassette was constructed. Co-transfection of the minigenome construct with SCRV-supporting plasmids of N, P, and L in BSRT7 cells resulted in the expression of the reporter gene. Transcription of a positive-strand RNA copy from cDNA of the SCRV genome along with the viral N, P, and L proteins resulted in the recovery of infectious SCRV in cells. Viral titre up to 10⁸  PFU/ml was achieved. Recombinant SCRV was verified by the detection of a unique restriction site engineered into the SCRV genome. The phenotypes of the recombinant SCRV and the parental virus were evaluated by plaque size, replication kinetics in vitro, and pathogenicity in vivo. The recovered SCRV from cDNA showed similar phenotypes compared to the parental virus. The established reverse genetics system is of great significance and value for the functional genome study of SCRV and for laying a foundation for the development of the viral vector and SCRV vaccine.