Login
Login

Macronovirus

{{Short description|Genus of virus}}

{{Use dmy dates|date=October 2023}}

{{Virusbox

| nam

| image = OPSR.Sarthro.Fig1l.v1.png-640x480.png

| image_alt =

| image_caption = Transmission electron micrographs of negatively-stained Extra small virus; bar = 50 nm

| taxon = Macronovirus

| subdivision_ranks = Species

| subdivision =

  • Macronovirus macrobrachii

| synonyms = * Macrobrachium satellite virus 1

| synonyms_ref = {{cite web|title=History of the taxon: Species: Macronovirus macrobrachii (2024 Release, MSL #40)|url=https://ictv.global/taxonomy/taxondetails?taxnode_id=202405047&taxon_name=Macronovirus%20macrobrachii|publisher=International Committee on Taxonomy of Viruses|access-date=22 March 2025}}

}}

Macronovirus is the only genus of the family Sarthroviridae. It contains one species: Extra small virus (XSV, Macronovirus macrobrachii).{{cite web|title=Virus Taxonomy: 2024 Release|url=https://ictv.global/taxonomy|publisher=International Committee on Taxonomy of Viruses|access-date=22 March 2025}}

It is found in The French West Indies, Thailand, Taiwan, China, and India.{{cite web |title=Macronovirus ~ ViralZone report|url=https://viralzone.expasy.org/7918 |website=ViralZone |access-date=12 August 2023 |language=en }}{{Creative Commons text attribution notice|cc=by4|from this source=yes}}

Etymology

The genus name, Macronovirus, is a combination of Macro, from the host Macrobrachium rosenbergii and no, from helper virus nodavirus.

The family name, Sarthroviridae, is a combination of S, from Small and arthro, from host arthropoda.{{cite web |title=Sarthroviridae ~ ViralZone report|url=https://viralzone.expasy.org/7917 |website=ViralZone |access-date=12 August 2023 |language=en }}{{Creative Commons text attribution notice|cc=by4|from this source=yes}}

Hosts

Macronovirus's cell tropism is muscle and connective cells of diseased animals, and its natural hosts are arthropods.

Structure

The virion of XSV has a genome consisting of linear single-stranded RNA of positive polarity, 0.8kb in size, with two genes. This encodes two capsid proteins, CP-17 and CP-16. The virion is non-enveloped, spherical, with a capsid of about 15 nm with icosahedral symmetry. The virion is constructed from two capsid proteins CP-17 and CP-16. It has a Monopartite, linear, ssRNA(+) genome.

Gene expression

The virion RNA is infectious and serves as both the genome and viral messenger RNA.

Replication

Its replication is cytoplasmic, and has 8 steps.

  1. Attachement to host receptors mediates entry into the host cell.
  2. Uncoating, and release of the viral genomic RNA into the cytoplasm.
  3. Viral RNA is translated in a polyprotein to produce replication proteins.
  4. Replication by helper virus occurs in viral factories made of membrane vesicles derived from the ER. A dsRNA genome is synthesized from the genomic ssRNA(+).
  5. The dsRNA genome is transcribed/replicated thereby providing viral mRNAs/new ssRNA(+) genomes.
  6. Expression of the capsid proteins.
  7. Assembly of new virus particles.
  8. Virus release.

Disease

Whitish muscle disease, which develops in post-larvae of freshwater prawn Macrobrachium rosenbergii and is caused by Macrobrachium rosenbergii nodavirus (MrNV) and its associate Extra small virus. Main symptom is a whitish appearance of the muscles, particularly noticeable in the abdomen. Mortalities can reach 100%.

References

{{Reflist}}

{{Taxonbar|from1=Q24802361|from2=Q24806027|from3=Q24809514}}

Category:Virus genera

Category:Riboviria