This article lists the changes to virus taxonomy approved and ratified by the International Committee on Taxonomy of Viruses in February 2018. A total of 451 species, 69 genera, 11 subfamilies, 9 ...families and one new order were added to the taxonomy. The current totals at each taxonomic level now stand at 9 orders, 131 families, 46 subfamilies, 803 genera and 4853 species. A change was made to the International Code of Virus Classification and Nomenclature to allow the use of the names of people in taxon names under appropriate circumstances. An updated Master Species List incorporating the approved changes was released in March 2018 (
https://talk.ictvonline.org/taxonomy/
).
Members of the family Secoviridae are non-enveloped viruses with mono- or bipartite (RNA-1 and RNA-2) linear positive-sense ssRNA genomes with the size of the RNAs combined ranging from 9 to 13.7 kb. ...They are related to picornaviruses and are classified in the order Picornavirales. The majority of known members infect dicotyledonous plants and many are important plant pathogens (e.g. grapevine fanleaf virus and rice tungro spherical virus). This is a summary of the current International Committee on Taxonomy of Viruses (ICTV) report on the taxonomy of the family Secoviridae available at www.ictv.global/report/secoviridae.
This article lists the changes to virus taxonomy approved and ratified by the International Committee on Taxonomy of Viruses (ICTV) in April 2016.
Changes to virus taxonomy (the Universal Scheme of ...Virus Classification of the International Committee on Taxonomy of Viruses ICTV) now take place annually and are the result of a multi-stage process. In accordance with the ICTV Statutes (
http://www.ictvonline.org/statutes.asp
), proposals submitted to the ICTV Executive Committee (EC) undergo a review process that involves input from the ICTV Study Groups (SGs) and Subcommittees (SCs), other interested virologists, and the EC. After final approval by the EC, proposals are then presented for ratification to the full ICTV membership by publication on an ICTV web site (
http://www.ictvonline.org/
) followed by an electronic vote. The latest set of proposals approved by the EC was made available on the ICTV website by January 2016 (
https://talk.ictvonline.org/files/proposals/
). A list of these proposals was then emailed on 28 March 2016 to the 148 members of ICTV, namely the EC Members, Life Members, ICTV Subcommittee Members (including the SG chairs) and ICTV National Representatives. Members were then requested to vote on whether to ratify the taxonomic proposals (voting closed on 29 April 2016).
We mark the 50th anniversary of the International Committee on Taxonomy of Viruses (ICTV) by presenting a brief history of the organization since its foundation, showing how it has adapted to ...advancements in our knowledge of virus diversity and the methods used to characterize it. We also outline recent developments, supported by a grant from the Wellcome Trust (UK), that are facilitating substantial changes in the operations of the ICTV and promoting dialogue with the virology community. These developments will generate improved online resources, including a freely available and regularly updated ICTV Virus Taxonomy Report. They also include a series of meetings between the ICTV and the broader community focused on some of the major challenges facing virus taxonomy, with the outcomes helping to inform the future policy and practice of the ICTV.
We present a taxonomic proposal for revision of the family
Secoviridae
, a taxon of plant viruses in the order
Picornavirales
. We propose the reorganization of the genus
Sadwavirus
to create three ...new subgenera and to update the classification of five existing species. The proposed subgenera are “
Satsumavirus
” (one species:
Satsuma dwarf virus
), “
Stramovirus
” (two species:
Strawberry mottle virus
and
Black raspberry necrosis virus
) and “
Cholivirus
” (two species:
Chocolate lily virus A
and
Dioscorea mosaic associated virus
).
This article reports the changes to virus taxonomy approved and ratified by the International Committee on Taxonomy of Viruses (ICTV) in October 2018. Of note, the ICTV has approved, by an absolute ...majority, the creation of additional taxonomical ranks above those recognized previously. A total of 15 ranks (realm, subrealm, kingdom, subkingdom, phylum, subphylum, class, subclass, order, suborder, family, subfamily, genus, subgenus, and species) are now available to encompass the entire spectrum of virus diversity. Classification at ranks above genus is not obligatory but can be used by the authors of new taxonomic proposals when scientific justification is provided.
In 2018, the family
Arenaviridae
was expanded by inclusion of 1 new genus and 5 novel species. At the same time, the recently established order
Bunyavirales
was expanded by 3 species. This article ...presents the updated taxonomy of the family
Arenaviridae
and the order
Bunyavirales
as now accepted by the International Committee on Taxonomy of Viruses (ICTV) and summarizes additional taxonomic proposals that may affect the order in the near future.
This review focuses on the extensive membrane and organelle rearrangements that have been observed in plant cells infected with RNA viruses. The modifications generally involve the formation of ...spherules, vesicles, and/or multivesicular bodies associated with various organelles such as the endoplasmic reticulum and peroxisomes. These virus-induced organelles house the viral RNA replication complex and are known as virus factories or viroplasms. Membrane and organelle alterations are attributed to the action of one or two viral proteins, which additionally act as a scaffold for the assembly of a large complex of proteins of both viral and host origin and viral RNA. Some virus factories have been shown to align with and traffic along microfilaments. In addition to viral RNA replication, the factories may be involved in other processes such as viral RNA translation and cell-to-cell virus transport. Confining the process of RNA replication to a specific location may also prevent the activation of certain host defense functions.
Plant viruses recruit cellular translation factors not only to translate their viral RNAs but also to regulate their replication and potentiate their local and systemic movement. Because of the virus ...dependence on cellular translation factors, it is perhaps not surprising that many natural plant recessive resistance genes have been mapped to mutations of translation initiation factors eIF4E and eIF4G or their isoforms, eIFiso4E and eIFiso4G. The partial functional redundancy of these isoforms allows specific mutation or knock-down of one isoform to provide virus resistance without hindering the general health of the plant. New possible targets for antiviral strategies have also been identified following the characterization of other plant translation factors (eIF4A-like helicases, eIF3, eEF1A and eEF1B) that specifically interact with viral RNAs and proteins and regulate various aspects of the infection cycle. Emerging evidence that translation repression operates as an alternative antiviral RNA silencing mechanism is also discussed. Understanding the mechanisms that control the development of natural viral resistance and the emergence of virulent isolates in response to these plant defense responses will provide the basis for the selection of new sources of resistance and for the intelligent design of engineered resistance that is broad-spectrum and durable.
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