Notes on Genus: Coltivirus


Type member: Colorado tick fever virus


General Description

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, Colorado tick 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
Protein Functions
14350VP1 163.0RNA polymerase
23909VP2 137.0Methyltansferase
33586VP3 135.0RNA replication factors
43157VP4 112.4
52432VP5 83.8 Guanylyltransferase
62141VP6 77.6Nucleotide binding, NTPase
72133VP7 76.2RNA replication factors
82029VP8 73.9
91884VP9 67.3Kinase, helicase
101880VP10 68.9
11998VP11 28.4
12675VP12 20.4RNA replication factors