Isolation, Identification, and Genomic Analysis of a Novel Reovirus from Healthy Grass Carp and Its Dynamic Proliferation In Vitro and In Vivo

A new grass carp reovirus (GCRV), healthy (HGCRV), was isolated from in 2019. Its complete genome sequence determined and contained 11 dsRNAs with a total size of 23,688 bp 57.2 mol% G+C content, encoding 12 proteins. All segments had conserved 5' 3' termini. Sequence comparisons showed that HGCRV closely related to GCRV-873 (GCRV-I; 69.57–96.71% protein identity) but shared only 22.65–45.85% 23.37–43.39% identities GCRV-HZ08 Hubei disease (HGDRV), respectively. RNA-dependent RNA-polymerase (RdRp) protein-based phylogenetic analysis clustered Aquareovirus-C (AqRV-C) prior joining branch common other aquareoviruses. Further using VP6 amino acid sequences Chinese GCRV strains the same evolutionary cluster as GCRV-I. Thus, could be isolate GCRV-I is distantly known GCRVs. Grass infected did not exhibit signs hemorrhage. Interestingly, induced typical cytopathic effect fish cell lines, such shrank, apoptosis, plague-like syncytia. proliferate liver (L28824), gibel brain (GiCB), reaching titer up 7.5 × 104 copies/μL.