Description of Luteoviridae
adapted from
ICTVdb
Virion Properties
Morphology
Virions consist of a
capsid. Virus capsid is not enveloped, round with icosahedral
symmetry. The isometric capsid has a diameter of 25-30 nm.
Capsids appear round, or hexagonal in outline. The capsomer
arrangement is clearly visible, or is not obvious. The capsid
consists of 32 capsomers.
Electron microscopic preparation and references: Virus
preparation contains few virions.
Physicochemical and Physical Properties
Virions have a buoyant density in
CsCl of 1.38-1.42 g cm
-3.
Nucleic Acid
The Mr of the genome constitutes 28-37% of the
virion by weight. The genome is not segmented and contains a
single molecule of linear positive-sense, single-stranded RNA.
Minor species of non-genomic nucleic acid are also found in
virions. The encapsidated nucleic acid is mainly of genomic
origin, but virions may also contain satellite RNA. The genome is
sequenced, and complete sequence is about 5600-6044-6900
nucleotides long. The 5'-end of the genome has a genome-linked
protein (VPg).
Proteins
Proteins constitute about 70-72% of
the particle weight.
The viral genome encodes structural proteins and
non-structural proteins. Virions consist of 1 structural
protein(s), or 2 structural protein(s), or 4 structural
protein(s).
Non-Structural Proteins: Virus-coded
non-structural proteins have been isolated, or identified by
sequence analysis and 3 non-structural protein(s) are found, or 6
non-structural protein(s) are found.
Lipids
Lipids are absent.
Genome Organization and Replication
By itself, genomic nucleic acid is infectious.
Translation: The genome
replicates in the cytoplasm.