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00.060.0.09. Oryzavirus
Cite this publication as: ICTVdB Management (2006).
00.060.0.09. Oryzavirus. In: ICTVdB - The Universal Virus Database,
version 4. Büchen-Osmond, C. (Ed), Columbia University, New York, USA
Cite this site as: ICTVdB - The Universal Virus Database, version 4.
http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/
This is a description of a
plant and invertebrate (viruses replicate in both hosts and are
transmitted by viruliferous planthoppers to Poacea) virus
at the genus level.
ICTVdB Virus Code: 00.060.0.09. Virus accession number:
060009GE. Obsolete virus code: 60.0.9.; superceded accession number: 60090000.
NCBI Taxon Identifier NCBI Taxonomy ID:
10992.
Name, Synonyms and Lineage
Synonym(s): Plant
reovirus subgroup 3. Virus is of the family
00.060.
Reoviridae.
Virions consist of a capsid, a core, and a nucleoprotein
complex. Virus capsid is not enveloped. Capsid/nucleocapsid is round and
exhibits icosahedral symmetry. The capsid is isometric. The
capsid shells of virions are composed of a single inner capsid layer. The outer
shell is not present. Capsids appear round. The capsid surface structure reveals
a regular pattern with distinctive features. The capsomer arrangement is clearly
visible, or is not obvious. Surface projections are distinct "B"-type
spikes protruding from the 12 vertices. The spikes are 8-10 nm long,
23-26 nm wide at the base and 14-17 nm at the top, that overlie the
core). Inner capsids consist of a 65-80 nm. The core subcore is
spherical (and smooth with no spikes) with a diameter of 50 nm.
Only one species is recovered in preparations.
Electron microscopic preparation and references: Virus preparation
contains few virions, or many virions.
There are 1 sedimenting component(s) found in purified
preparations, or 2 sedimenting component(s) found in purified preparations.
A260/A280 ratio is 1.8. The thermal inactivation point
(TIP) is at 70-75-80°C. The longevity in vitro (LIV) is 3
days. Although the titer is dependent on the host, the decimal exponent (DEX) of
the dilution end point is usually around 6-7.
The
genome is segmented and consists of ten segments of linear
double-stranded RNA. Minor species of non-genomic nucleic
acid are not found in virions. The complete genome is
26640-26650-26660 nucleotides long. RNA-1 is sequenced,
and complete sequence is about 3850-3875-3900
nucleotides long. RNA-2 is sequenced, but only an estimate is available,
complete sequence is 3820-3860-3900 nucleotides long. RNA-3
is sequenced, but only an estimate is given, complete sequence is 3800
nucleotides long. RNA-4 has been sequenced, but only an estimate is provided;
complete sequence is 3700-3750-3800 nucleotides long. RNA-5 has been
sequenced, but only an estimate is presented, complete sequence is
2700-2725-2750 nucleotides long. RNA-6 has been sequenced,
but only an estimate is given, complete sequence is
2300-2450-2600 nucleotides long, has been sequenced, but only
an estimate is presented; complete sequence is 1950 nucleotides long. RNA-8
has been sequenced, but only an estimate is available,
complete sequence is 1900 nucleotides long. RNA-9 has been sequenced,
complete sequence is about 1200
nucleotides long. RNA-10 has been sequenced, but only an estimate is
available; complete sequence is 1160 nucleotides long. The 5'-terminal
sequence has conserved regions; terminal repeats at the 5'-end are 6
nucleotides long (5' GAUAAA....GUGC 3'). The 3'-terminus has conserved
nucleotide sequences; of 4 nucleotides in length; sequence has conserved
regions; in some RNA segments (but different from those of phytoreoviruses or
Fijiviruses).
GenBank records for
nucleotide sequences;
complete genome sequences.
The viral
genome encodes structural proteins and non-structural proteins. Virions consist
of 6 structural protein(s), or 8 structural protein(s).
Lipids are
absent.
Genome Organization and Replication
By
itself, genomic nucleic acid is not infectious.
Translation: The genome replicates in
cytoplasmic viroplasma.
Natural Host
Domain
Viral hosts belong to the Domain
Eucarya.
Domain Eucarya
Kingdom Plantae.
Kingdom Plantae
Phylum Magnoliophyta
(Angiosperms, Class Liliopsida (Monocotyledonae).
Severity and Occurrence of
Disease
Host: Signs and symptoms persist.
Virus is transmitted by a vector. Virus is transmitted by
mechanical inoculation, or not transmitted by mechanical inoculation; not
transmitted by grafting; not transmitted by contact between hosts; not
transmitted by seeds; not transmitted by pollen.
Vector Transmission:
Virus is transmitted by arthropods, by insects
of the order Hemiptera, family Delphacidae. Virus is transmitted in a persistent
manner; retained when the vector moults; replicates in the vector; not
transmitted congenitally to the progeny of the vector; does not require a helper
virus for vector transmission.
Experimental Hosts and Symptoms
Under
experimental conditions susceptibility to infection by virus is found in few
families. Susceptible host species are found in the Family Gramineae. The
following species were susceptible to experimental virus infection:
Alopecurus aequalis, Echinochloa crus-galli, Echinochloa
crus-galli var. formosensis, Echinochloa crus-galli var.
oryzicola, Eleusine coracana, Hordeum vulgare,
Imperata cylindrica, Imperata cylindrica var. major,
Lolium multiflorum, Oryza latifolia, Oryza nivara,
Oryza sativa, Setaria italica, Triticum aestivum,
Zea mays.
Experimentally infected insusceptible Hosts: Families
containing insusceptible hosts: Gramineae. Species inoculated with virus that do
not show signs of susceptibility: Cynodon dactylon, Echinochloa
colona, Eleusine indica, Hordeum vulgare, Leersia
hexandra, Saccharum officinarum, Sorghum bicolor,
Triticum aestivum.
Histopathology: Virions are found in the cytoplasm.
Cytopathology: Inclusions are present in infected cells.
Inclusion bodies in the host cell are found in the cytoplasm. Cytoplasmic
inclusions are viroplasma. Inclusions contain mature virions.
The virus occurs in Bangladesh, or China, or India, or
Indonesia, or Japan, or Malaysia, or the Philippines, or Sri Lanka, or Taiwan,
or Thailand.
Type species 00.060.0.09.001.
Rice ragged stunt virus .
List of Species in the
Genus.
Data Sources and
Contributions
The description has been compiled from data in the
ICTV Report presented by Holmes IH, Boccardo G, Estes MK, Furuichi MK,
Hoshino Y, Joklik WK, McCrae M, Mertens PPC, Milne RG, Samal KSK, Shikata E,
Winton JR, Uyeda I, Nuss DL.
The
following generic references are cited in the most recent ICTV Report.
PubMed References.
A description of the virus is found
in DPV, a database for plant viruses developed by the Association of Applied
Biologists (AAB), with the number
294.
Taxonomic Proposals and Changes
Rice ragged
stunt was suggested as new genus because it has a distinct morphology unlike any
other reo-like virus (though it somewhat resembles 60.0.6. Cypovirus
without the matrix protein). The size distribution of the 10 dsRNA segments is
unlike that of other Reoviridae. No serological relationships with any other
plant reo-like virus. On the other hand, the symptoms, cytopathology,
vector type and number of RNA segments, are similar to those of Fijivirus.