Picornavirales, a proposed order of positive-sense single-stranded RNA viruses with a pseudo-T = 3 virion architecture

  title={Picornavirales, a proposed order of positive-sense single-stranded RNA viruses with a pseudo-T = 3 virion architecture},
  author={Olivier Le Gall and Peter Christian and Claude M. Fauquet and Andrew M. Q. King and Nick J. Knowles and Nobuhiko Nakashima and Glyn Stanway and Alexander E. Gorbalenya},
  journal={Archives of Virology},
Despite the apparent natural grouping of “picorna-like” viruses, the taxonomical significance of this putative “supergroup” was never addressed adequately. We recently proposed to the ICTV that an order should be created and named Picornavirales, to include viruses infecting eukaryotes that share similar properties: (i) a positive-sense RNA genome, usually with a 5′-bound VPg and 3′-polyadenylated, (ii) genome translation into autoproteolytically processed polyprotein(s), (iii) capsid proteins… 
Polycipiviridae: a proposed new family of polycistronic picorna-like RNA viruses
The formation of a new virus family, Polycipiviridae, is proposed to classify this clade of arthropod-infecting polycistronic picorna-like viruses, and it is proposed that this family be divided into three genera: Chipolycivirus, Hupolycavirus and Sopolycvirus, with members of the latter infecting ants in at least 3 different subfamilies.
Aphis glycines virus 1, a new bicistronic virus with two functional internal ribosome entry sites, is related to a group of unclassified viruses in the Picornavirales.
In phylogenetic analyses based on capsid protein and RNA-dependent RNA polymerase sequences, ApGlV1 consistently clustered with a group of unclassified bicistronic picorna-like viruses discovered from arthropods and plants that may represent a novel family in the order Picornavirales.
The Nonstructural Protein 2C of a Picorna-Like Virus Displays Nucleic Acid Helix Destabilizing Activity That Can Be Functionally Separated from Its ATPase Activity
It is revealed that a picorna-like virus 2C protein displays RNA helix destabilizing and strand annealing acceleration activity, which may be critical for picornaviral replication and pathogenesis, and should foster the understanding of picornA-like viruses and viral RNA chaperones.
A Novel Rice Curl Dwarf-Associated Picornavirus Encodes a 3C Serine Protease Recognizing Uncommon EPT/S Cleavage Sites
It is shown that the two polyproteins of RCDaV can be cleaved into 12 mature proteins, and it is found that seven unclassified picornaviruses also encode a 3Cpro similar to R CDaV, and use the highly conserved EPT/S as the cleavage site.
Secoviridae: A Family of Plant Picorna-Like Viruses with Monopartite or Bipartite Genomes
A recent update in the taxonomy of plant picorna-like viruses has led to the creation of the family Secovirids, which amalgamates the previous families Comoviridae and Sequiviridae as well as the genera Cheravirus, Sequivirus and Torradovirus.
Structure of Nora virus at 2.7 Å resolution and implications for receptor binding, capsid stability and taxonomy
The structure of Nora virus is solved and it is proposed that Nora virus, and a small group of related viruses, should have its own family within the order Picornavirales.


High diversity of unknown picorna-like viruses in the sea
It is reported, on the basis of analysis of RdRp sequences amplified from marine virus communities, that a diverse array of picorna-like viruses exists in the ocean and fell within four monophyletic groups that probably belong to at least two new families.
Evolutionary and taxonomic implications of conserved structural motifs between picornaviruses and insect picorna-like viruses
It is proposed that the picornaviruses, Cricket paralysis-like viruses and IFV/SBV group are a natural assemblage that had a structure based upon the CrPV/picornavirus paradigm and a genome encoding a single major coat protein.
RNA helicase: a novel activity associated with a protein encoded by a positive strand RNA virus.
The PPV CI protein, which belongs to the potyvirus group of positive strand RNA viruses, is shown to be able to unwind RNA duplexes, and this is the first report on a helicase activity associated with a protein encoded by an RNA virus.
Genetics, Pathogenesis and Evolution of Picornaviruses
Naturally Occurring Dicistronic Cricket Paralysis Virus RNA Is Regulated by Two Internal Ribosome Entry Sites
The cricket paralysis virus genome is an example of a naturally occurring, functionally dicistronic eukaryotic mRNA whose translation is controlled by two IRES elements located at the 5′ end and in the middle of the mRNA, arguing that eukARYotic mRNAs can express multiple proteins not only by polyprotein processing, reinitiation and frameshifting but also by using multiple IRES Elements.
Evidence for common ancestry of a chestnut blight hypovirulence-associated double-stranded RNA and a group of positive-strand RNA plant viruses.
Comparison of the organization of the conserved domains within the encoded polyproteins of the respective viruses indicated that the proposed subsequent evolution involved extensive genome rearrangement.
The phylogeny of RNA-dependent RNA polymerases of positive-strand RNA viruses.
  • E. Koonin
  • Biology
    The Journal of general virology
  • 1991
Phylogenetic analysis using three independent methods of three construction confirmed the separation of the positive-strand RNA viral polymerases into three supergroups and revealed some unexpected clusters within the supergroups.
Sequence analysis of the parsnip yellow fleck virus polyprotein: evidence of affinities with picornaviruses.
Despite these similarities in sequence and in genome organization to viruses in the picorna-like supergroup, PYFV is distinct from all other plant and animal viruses described, which justifies placing it in a separate plant virus genus for which the name 'sequivirus' has been proposed.
Similarity in gene organization and homology between proteins of animal picornaviruses and a plant comovirus suggest common ancestry of these virus families.
The amino acid sequences deduced from the nucleic acid sequences of several animal picornaviruses and cowpea mosaic virus and CPMV, a plant virus, were compared to conclude that the proteinases encoded by these viruses are probably cysteine proteinases, mechanistically related, but not homologous to papain.