The Complete Genome Sequence of Perina nuda Picorna-like Virus, An Insect-Infecting RNA Virus with a Genome Organization Similar to That of the Mammalian Picornaviruses

Abstract

Perina nuda picorna-like virus (PnPV) is an insect-infecting RNA virus with morphological and physicochemical characters similar to the Picornaviridae. In this article, we determine the complete genome sequence and analyze the gene organization of PnPV. The genome of PnPV consists of 9476 nucleotides (nts) excluding the poly(A) tail and contains a single large open reading frame (ORF) of 8958 nts (2986 codons) flanked by 473 and 45 nt noncoding regions on the 5' and 3' ends, respectively. Northern blotting did not detect the presence of any subgenomic RNA. The PnPV genome codes for four structural proteins (CP1-4), and determination of their N-terminal sequences by Edman degradation, showed that all four are located in the 5' region of the genome. The 3' part of the PnPV genome contains the consensus sequence motifs for picornavirus RNA helicase, cysteine protease, and RNA-dependent RNA polymerase (RdRp) in that order from the 5' to the 3' end. In all of these characters, the genome organization of PnPV resembles the mammalian picornaviruses and two other insect picorna-like viruses, infectious flacherie virus (IFV) of the silkworm and Sacbrood virus (SBV) of the honeybee. In a phylogenetic tree based on the eight conserved domains in the RdRp sequence, PnPV formed a separate cluster with IFV and SBV, which suggests that these three insect picorna-like viruses might constitute a novel group of insect-infecting RNA viruses.

A novel virus isolated from the aphid Brevicoryne brassicae with similarity to Hymenoptera picorna-like viruses

“…)] and resembles the hairpin structures found close to the 59 termini of the genomic RNAs of Perina nuda virus (PnV) and Ectropis obliqua picorna-like virus (EoPV) (Ongus et al, 2006;Wang et al, 2004;Wu et al, 2002 )], which do not have much in common with those identified in other iflaviruses (Ongus et al, 2006). High diversity of the 59-NTR secondary structure elements has been reported, for example, in the family Picornaviridae (Witwer et al, 2001).…”

A case for “StopGo”: Reprogramming translation to augment codon meaning of GGN by promoting unconventional termination (Stop) after addition of glycine and then allowing continued translation (Go)

“…The first PnPV 2A-encoding RNA sequence, codons 556-573, with the potential to code for QGWVPDLTVDGDVESNPG is at the 39 end of the cp1 gene and the first codon, 574, of the adjacent cp2 gene specifies proline. This proline was confirmed by N-terminal sequence analysis (Wu et al 2002). The second PnPV 2A-encoding RNA sequence, codons 1173-1190, with the potential to code for GGGQKDLTQDGDIESNPG, is in the vicinity of the predicted 39 end of the cp4 gene and the 39 adjacent codon, 1191, is a proline codon (Wu et al 2002).…”

“…The single-stranded RNA Perina nuda picorna-like virus, PnPV, which infects a moth, has these features and also has an additional 2A-encoding sequence where only the upstreamencoded product is present in the virion ( Fig. 1; Wu et al 2002). This virus can be readily propagated in a homologous insect cell line (Wu et al 2002).…”

“…1; Wu et al 2002). This virus can be readily propagated in a homologous insect cell line (Wu et al 2002).…”

“…The PnPV genome has a single ORF that has 2986 codons and does not generate subgenomic RNAs (Wu et al 2002). It is 89% identical at the amino acid level to Ectropis obliqua picorna-like virus (Wang et al 2004;Lu et al 2006), and less so (25%) to Infectious flacherie virus (Isawa et al 1998).…”