Notes on Genus: Seadornavirus

icosahedra

Type member: Kadipiro virus

General Description

This is one of the animal virus genera in the family Reoviridae. Members were previously classified as subgroup B of the genus Coltivirus with which they share some similarity. Both genera have 12 genome segments but in the genus Seadornavirus the total genome is smaller, the segment sizes are more evenly spaced than in the coltiviruses and the viruses have been isolated from mosquitoes rather than ticks. The name reflects their position as South eastern Asia dodeca RNA viruses.

Morphology

Virions isometric (icosahedral), 60-80 nm in diameter, with two concentric capsid shells surrounding a core of c.50nm diameter. The particle surface is relatively smooth.

Genome

Linear, double stranded RNA in 12 segments. Each virion contains a single copy of the entire genome. Total genome c.21000 nucleotides long.

Genus Genomic Organization

Each segment has a single ORF. The RNA polymerase is encoded by the largest segment, but the functions of most of the other encoded proteins have still to be determined.

Type Member Genomic Organization

Segment 1 (3774 nt) encodes the RNA polymerase (VP1) protein of 138.5 kDa
Segment 2 (3035 nt) encodes the VP2 protein (108.3 kDa)
Segment 3 (2415 nt) encodes the VP3 protein (85.5 kDa)
Segment 4 (2121 nt) encodes the VP4 protein (69.3 kDa)
Segment 5 (1947 nt) encodes the VP5 protein (64.0 kDa)
Segment 6 (1670 nt) encodes the VP6 protein (56.2 kDa)
Segment 7 (1259 nt) encodes the VP7 protein (38.9 kDa)
Segment 8 (1114 nt) encodes the VP8 protein (33.2 kDa)
Segment 9 (1054 nt) encodes the VP9 protein (32.9 kDa)
Segment 10 (946 nt) encodes the VP10 protein (29.7 kDa)
Segment 11 (894 nt) encodes the VP 11 protein (28.7 kDa)
Segment 12 (756 nt) encodes the VP12 protein (20.6 kDa )