RNA Virus

A RNA Virus is a virus that has RNA (ribonucleic acid) as its genetic material.

• Context:
  • It can range from being a Single-Stranded RNA Virus to being a Double-Stranded RNA Virus.
  • …
• Example(s):
  • a Common Cold Virus.
  • a Flu Virus.
  • a Coronavirus, such as a Betacoronavirus, such as: SARS-Cov-2.
  • a Caliciviridae, such as Norovirus.
  • …
• Counter-Example(s):
  • a DNA Virus.
• See: Enveloped Virus, Ebola Virus, Rabies Virus.

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References

2020

• (Wikipedia, 2020) ⇒ https://en.wikipedia.org/wiki/RNA_virus Retrieved:2020-2-25.
  • An RNA virus is a virus that has RNA (ribonucleic acid) as its genetic material. This nucleic acid is usually single-stranded RNA (ssRNA) but may be double-stranded RNA (dsRNA). Notable human diseases caused by RNA viruses include Ebola virus disease, SARS, rabies, common cold, influenza, hepatitis C, hepatitis E, West Nile fever, polio, measles, and coronavirus. The International Committee on Taxonomy of Viruses (ICTV) classifies RNA viruses as those that belong to Group III, Group IV or Group V of the Baltimore classification system of classifying viruses and does not consider viruses with DNA intermediates in their life cycle as RNA viruses. Viruses with RNA as their genetic material which also include DNA intermediates in their replication cycle are called retroviruses, and comprise Group VI of the Baltimore classification. Notable human retroviruses include HIV-1 and HIV-2, the cause of the disease AIDS. Another term for RNA viruses that explicitly excludes retroviruses is ribovirus.

2018

• (Wolf et al., 2018) ⇒ Yuri I. Wolf, Darius Kazlauskas, Jaime Iranzo, Adriana Lucía-Sanz, Jens H. Kuhn, Mart Krupovic, Valerian V. Dolja, and Eugene V. Koonin. (2018). “Origins and Evolution of the Global RNA Virome.” MBio 9(6).
  • ABSTRACT: Viruses with RNA genomes dominate the eukaryotic virome, reaching enormous diversity in animals and plants. The recent advances of metaviromics prompted us to perform a detailed phylogenomic reconstruction of the evolution of the dramatically expanded global RNA virome. The only universal gene among RNA viruses is the gene encoding the RNA-dependent RNA polymerase (RdRp). We developed an iterative computational procedure that alternates the RdRp phylogenetic tree construction with refinement of the underlying multiple-sequence alignments. The resulting tree encompasses 4,617 RNA virus RdRps and consists of 5 major branches; 2 of the branches include positive-sense RNA viruses, 1 is a mix of positive-sense (+) RNA and double-stranded RNA (dsRNA) viruses, and 2 consist of dsRNA and negative-sense (−) RNA viruses, respectively. This tree topology implies that dsRNA viruses evolved from +RNA viruses on at least two independent occasions, whereas −RNA viruses evolved from dsRNA viruses. Reconstruction of RNA virus evolution using the RdRp tree as the scaffold suggests that the last common ancestors of the major branches of +RNA viruses encoded only the RdRp and a single jelly-roll capsid protein. Subsequent evolution involved independent capture of additional genes, in particular, those encoding distinct RNA helicases, enabling replication of larger RNA genomes and facilitating virus genome expression and virus-host interactions. Phylogenomic analysis reveals extensive gene module exchange among diverse viruses and horizontal virus transfer between distantly related hosts. Although the network of evolutionary relationships within the RNA virome is bound to further expand, the present results call for a thorough reevaluation of the RNA virus taxonomy.

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