Figure 1.
Genetics and genomics of PARV4.
(A) Neighbour-joining phylogenetic tree reconstructed using amino acid sequences of ORF-1 (nonstructural protein) of Parvovirinae species. Sequences downloaded from NCBI (https://www.ncbi.nlm.nih.gov/genbank/). Sequences were selected based on completeness of sequence (minimum 621 amino acids per sequence), date of publication (all published between 2002 and 2010), and to provide representative viruses within each of the major Parvovirinae genera. Alignments and tree reconstruction were performed using Clustalw2 (http://www.ebi.ac.uk/Tools/msa/clustalw2). Subfamilies Densovirinae and Parvovirinae are indicated by dashed ovals. Genera within Parvovirinae are indicated by solid-coloured ovals and labelled with newly proposed genus nomenclature [23]. Viruses known to cause human infection are marked ‘*’. PARV4 genotypes 1–3 are in a new genus variously termed Partetravirus or Tetraparvovirus, together with animal parvoviruses (bovine and porcine hokovirus and PARV4-like viruses infecting nonhuman primates [8]) to which they are most closely related [2], [23]. Individual taxa are as follows, with GenBank ID in square brackets: PARV_1 = PARV4 genotype 1 [ACD71480.1]; PARV_2 = PARV4 genotype 2 [ABV71690.1]; PARV_3 = PARV4 genotype 3 [ACF94533.1]; PARV4_ch = PARV4-like virus of chimpanzees [AFD01617]; PARV4_co = PARV4-like virus of colobus monkey [AFD01599]; PHoV = porcine hokovirus [ADN44557.1]; BHoV = bovine hokovirus [ABY67685.1]; AAV_1 = adeno-associated virus 1 [AAU05367.1]; AAV_7 = adeno-associated virus 7 [YP_077177.1]; AAV_8 = adeno-associated virus 8 [YP_077179.1]; B19 = human parvovirus B19 [ABC87246.1]; AMDV = Aleutian mink disease virus [ACY54678.1]; MVM = minute virus of mice [ABB01353.1]; AADV = Aedes aegypti densovirus [YP_002854229.1]. Percentage amino acid sequence identity for tetraparvoviruses in comparison to PARV_1, calculated for NS1 protein using ClustalW2, are as follows: PARV4 _2, 96.4%; PARV4_3, 97.0%; PARV4_ch, 91.5%; PARV4_co, 67.8%; BHoV, 59.5%; PHoV, 58.1%. (B) Neighbour-joining phylogenetic tree reconstructed using full-length nucleotide sequences of species within the Tetraparvovirus subfamily. Methods and individual isolates as for Figure 1A. Percentage nucleotide sequence identity in comparison to PARV_1, calculated for full-length sequence using ClustalW2, are as follows: PARV4 _2, 92.1%; PARV4_3, 92.9%; PARV4_ch, 83.3%; PARV4_co, 71.3%; BHoV, 65.1%; PHoV, 65.3%. (C) Schematic diagram of PARV4 genome. Diagram based on NCBI Reference Sequence: NC_007018.1 [1]. Open Reading Frame 1 (ORF-1) encodes Non-Structural Protein 1 (NS-1); this region is responsible for potentially cytopathic effects of the virus [2]. Open Reading Frame 2 (ORF-2) comprises overlapping proteins Viral Protein 1 (VP-1) and Viral Protein 2 (VP-2), which encode structural capsid proteins. Protein lengths are shown as number of amino acids (aa). Additional Reading Frames (ARFs) are conserved across PARV4 genotypes; shown as ARF-1 (67 amino acids) and ARF-2 (86 amino acids) [5].
Table 1.
Clinical symptoms reported in subjects with PARV4 infection.