Roniviridae
Roniviridae | |
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Virus classification | |
Group: | Group IV ((+)ssRNA) |
Order: | Nidovirales |
Family: | Roniviridae |
Genera | |
Roniviridae is a family of virus of the order Nidovirales. The name is derived from their rod like shape - rod like nidoviridae.
Virology
The viruses in this family are enveloped, bacilliform-shaped, about 150–200 nanometers (nm) in length and 40–60 nm in diameter. The envelope has surface projections. These surface projections are prominent, distinctive peplomers surrounded by a prominent fringe. The nucleocapsid is elongated and has a helical symmetry with a diameter of 20–30 nm.
The genome is non segmented, linear, positive sense single-stranded RNA 26 kilobases in length. It is capped, and polyadenylated.
The genome encodes 6 open reading frames (ORF). The 5' and largest OFRs (OFR1a and ORF 1b) encode the RNA polymerase and other non structural proteins. OFR 1a is encoded by the genomic RNA. ORF 1b is encoded by a frameshift within OFR 1a and the sequence 3' of ORF 1b. The structural proteins (N, Gp116, Gp64 and ORF 4) are transcribed as sub genomic RNAs.
Protein encoded with the genome include a cysteine protease, RNA-dependent RNA polymerase, helicase and metal ion binding domains, nucleoprotein, and S glycoproteins.
Taxonomy
There is one genus in this family – Okavirus.