Birnaviridae
Baltimore Classification
Higher order taxa
Viruses; dsRNA viruses; Birnaviridae
Genera
Aquabirnavirus, Avibirnavirus, Entomobirnavirus
Description and Significance
Birnaviruses infect animals: vertebrates, insects, molluscs and crustaceans. They are bi-RNA viruses and have double stranded RNA genomes in two components.
Genome Structure
The genome of Binyaviridae is segmented and consists of linear double-stranded RNA. Minor species of non-genomic nucleic acid are also found in virions. The complete genome is 5880-6400 nucleotides long. Segment A has been fully sequenced and the complete sequence is 3100-3200 nucleotides long while segment B is 2750-2850 nucleotides long. The genome guanine+cytosine content is 45.5-54.5 %. The 5'-end of the genome has a cap on both segments genome-linked protein (VPg). The multipartite genome is found in one type of particle only. (source ICTV dB Descriptions)
The virions of a birnaviridae have a simple construction. The virions are not enveloped and consist of a capsid. The capsid is round and exhibits icosahedral symmetry.
