Notes on Genus: Coltivirus
Type member: Colorado tick fever virus
This is one of the animal virus genera in the family Reoviridae
. Viruses previously classifed as subgroup B of the genus (which have smaller genomes and have been isolated from mosquitoes rather than ticks) are now separated into the genus Seadornavirus
. The name derives from the type member, Col
ck fever virus.
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.
Linear, double stranded RNA in 12 segments. Each virion contains a single copy of the entire genome. Total genome c.
29000 nucleotides long. The segments migrate as three size classes in electrophoresis.
Genus Genomic Organization
Each segment has a single ORF. The RNA polymerase is encoded by the largest segment, but the location and functions of some of the other encoded proteins have still to be determined.
Type Member Genomic Organization
|Protein ||Protein Size|
|1||4350||VP1 ||163.0||RNA polymerase|
|3||3586||VP3 ||135.0||RNA replication factors|
|5||2432||VP5 ||83.8|| Guanylyltransferase|
|6||2141||VP6 ||77.6||Nucleotide binding, NTPase|
|7||2133||VP7 ||76.2||RNA replication factors|
|8||2029||VP8 ||73.9|| |
|9||1884||VP9 ||67.3||Kinase, helicase|
|12||675||VP12 ||20.4||RNA replication factors|