Discovery of novel tepovirus genomes with a nucleic acid-binding protein homolog by systematic analysis of plant transcriptome data

Some plant RNA viruses in the family Betaflexiviridae encode a nucleic acid-binding protein (NABP) that facilitates infection by suppressing the host RNA silencing response. Previously, no members of the genus Tepovirus within this family were known to possess a NABP homolog. In this study, we identified the genome sequences of 21 novel Betaflexiviridae viruses: 17 represent new members of Tepovirus , and four may be founding members of a new genus closely related to the genus Vitivirus . Notably, five of these newly identified tepoviruses contain a NABP-like open reading frame (ORF). Sequence comparison and phylogenetic analysis of NABP homologs suggest these tepoviruses independently acquired a NABP-like ORF from diverse sources. The identification of 17 novel viruses substantially enhances our understanding of the genetic diversity within the genus Tepovirus . This study further highlights the role of recombination in the genome evolution and diversity of Betaflexiviridae .