Closteroviridae. Closteroviridae

Description of Closteroviridae adapted from ICTVdb Virion Properties Morphology Virions consist of a capsid. Virus capsid is not enveloped. Capsid/nucleocapsid is elongated with helical symmetry. The capsid is filamentous and very flexuous with a length of 650-900 nm, or 1200-2200 nm and a width of 10-13 nm. Pitch of helix is 3.4-3.7 nm. Physicochemical and Physical Properties Virions have a buoyant density in CsCl of 1.33-1.34 g cm-3. Nucleic Acid The Mr of the genome constitutes 5% of the virion by weight. The genome is monopartite, only one particle size is recovered of linear, positive-sense, single-stranded RNA. The complete genome is 7500-19500 nucleotides long. The genome sequence has termini with potential hairpin structure (near 3'-end). The 5'-end of the genome has a probably methylated nucleotide cap. Proteins The viral genome encodes structural proteins and non-structural proteins. Lipids Lipids are not reported.