Identification of a novel member of the family Betaflexiviridae from the hallucinogenic plant Salvia divinorum

Abstract

Betaflexiviridae is a family of plant-infecting RNA viruses with 11 recognized genera, of which genomes have diverse organization with three to six open reading frames (ORFs). A genome sequence of a novel Betaflexiviridae species, named Salvia divinorum RNA virus 1 (SdRV1), was identified in Salvia divinorum, herbal mint plant with hallucinogenic properties. The SdRV1 genome was predicted to have four ORFs encoding a replicase polyprotein (REP), a movement protein (MP), a coat protein (CP), and a putative nucleic acid-binding protein (NBP). Phylogenetic analyses based on the REP, MP, and CP sequences indicated that SdRV1 is most closely related to members of the genus Citrivirus. However, the genome organization of SdRV1 is the same as that of the genus Prunevirus. Moreover, the SdRV1 NBP had greatest sequence similarity with members of the genus Carlavirus. A complex evolutionary history involving ancestors of these three genera might have resulted in the unique phylogenetic position of SdRV1, which could be considered the founding member of a new genus in the family Betaflexiviridae. The genome sequence of SdRV1 might be useful for studies on the evolution of Betaflexiviridae.