A positive-sense single-stranded RNA virus acquired a negative-sense open reading frame through recombination

Single stranded RNA viruses are broadly classified into positive-sense and negative-sense single-stranded RNA. This distinction is due to the different transcription and replication mechanisms. In this study, researchers identified and analyzed an RNA virus, Brine Shrimp Virga-like Virus 1 (BSVV1) found in brine shrimp. BSVV1’s genome included three Open Reading Frames (ORFs). ORF1 resembled the RdRp of Ips virga-like virus 1. ORF2 showed links to Hubei bunya-like virus 10. ORF3 had no known homologs. ORF2 was transcribed directly as in positive-sense viruses, but closely resembled the glycoprotein of various negative-sense bunyaviruses. This suggested ancient recombination between positive-sense and negative-sense RNA viruses. TEM imaging revealed non-enveloped viral particles (~50nm), but further studies are essential to confirm envelope absence or presence. The study established BSVV1 is globally distributed although its ecological spread is unclear requiring more research. BSVV1’s novel genome sequence shows significant evidence of recombination between distinct RNA virus phyla, offering new insights into virus evolution and diversity. Further studies should focus on understanding BSVV1’s protein functions and its impact on viral adaption.
(MKO)