Complete genome sequence of garlic latent virus, a member of the carlavirus family

The complete genome sequence of the garlic latent virus (GLV) has been determined. The whole GLV genome consists of 8,353 nucleotides, excluding the 3′-end poly(A)⁺ tail, and contains six open-reading frames (ORFs). Putative proteins that were encoded by the reading frames contain the motifs that were conserved in carlavirus-specific RNA replicases, NTP-dependent DNA helicases, two viral membrane-bound proteins, a viral coat protein, and a zinc-finger. Over-all, the GLV genome shows structural features that are common in carlaviruses. An in vitro translation analysis revealed that the zinc-finger protein is not produced as a transframe protein with the coat protein by ribosomal frameshifting. A Northern blot analysis showed that GLV-specific probes hybridized to garlic leaf RNA fragments of about 2.6 and 1.5 kb long, in addition to the 8.5 kb whole genome. The two subgenomic RNAs might be encapsidated into smaller viral particles. In garlic plants, 700 nm long flexuous rodshaped virus particles were observed in the immunoelectron microscopy using polyclonal antibodies against the GLV coat proteins.