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Type Species |
(PEMV-1) |
PEMV-1 occurs as part of a complex with PEMV-2 (an umbravirus). PEMV-1 is readily transmitted mechanically, a property dependent on its multiplication in cells co-infected with PEMV-2, but aphid transmissibility can be lost after several mechanical passages. Virions are found in mesopyll tissue as well as in vascular tissue. PEMV-1 will multiply when inoculated to isolated leaf protoplasts, but there is no evidence that it can spread in plants.
Enamovirus particles are of two distinct sizes, approximately 25 nm and 28 nm in diameter for the top (T) and bottom (B) components, respectively. A 180 subunit arrangement in a T = 3 icosahedron has been proposed for the B component and a 150 subunit arrangement lacking quasi-equivalence has been suggested for the T component. They have Mr of about 5.6 106 (B component) and 4.5 106 (T component). The virions have buoyant densities in CsCl solutions of 1.42 g/cm3 (B component) and S20w of 107-122S (B component) or 91-106S (T component).
Genome size is 5706 nts (PEMV-1). The PEMV-1 genome contains an ORF0, but does not contain either an ORF6 or an ORF4 (present in luteoviruses and poleroviruses). The PEMV-1 genome contains an ORF5 of about 730 nts. The non-coding intergenic region between ORF2 and ORF3 is about 200 nts in length. A protein is associated with virion RNA of PEMV-1. Virions of some strains of PEMV-1 + PEMV-2 contain a 717 nts satellite RNA in addition to genomic RNA.
List of Species Demarcation Criteria in the Genus
Not applicable.
Official virus species names are in italics. Tentative virus species names, alternative names ( ), strains or serotypes are not italicized. Virus names, CMI/AAB description numbers ( ), genome sequence accession numbers [ ], and assigned abbreviations ( ) are:
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Pea enation mosaic virus-1 (257) |
[L04573] |
(PEMV-1) |
Tentative Species in the Genus
None reported.
List of Unassigned Species in the Family
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Barley yellow dwarf virus - GPV |
[L10356] |
(BYDV-GPV) |
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Barley yellow dwarf virus - RMV (32) |
[Z14123, L12757, L12758, L12759] |
(BYDV-RMV) |
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Barley yellow dwarf virus - SGV (32) |
[U06865] |
(BYDV-SGV) |
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Bean leafroll virus (286) |
[X53865, U15978] |
(BLRV) |
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(Legume yellows virus) |
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(Michigan alfalfa virus) |
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(Pea leafroll virus) (286) |
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Carrot red leaf virus (249) |
(CtRLV) | |
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Chickpea stunt disease associated virus |
[Y11530] |
(CpSDaV) |
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Groundnut rosette assistor virus |
[Z68894] |
(GRAV) |
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Indonesian soybean dwarf virus |
(ISDV) | |
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Soybean dwarf virus (179) |
[L24049] |
(SbDV) |
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(Strawberry mild yellow edge associated virus) |
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(Subterranean clover red leaf virus) |
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Sweet potato leaf speckling virus |
(SPLSV) | |
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Tobacco necrotic dwarf virus (234) |
(TNDV) | |
Phylogenetic Relationships in the Family
Phylogenetic analysis of the predicted amino acid sequences of the polymerase (ORF2), CP (ORF3), and readthrough protein (ORF5) separate the members of the family Luteoviridae into the three genera (Fig. 3). SbDV, an unassigned species, groups with different genera depending on which sequence is analyzed. The CP sequences of BYDV-GPV, CpSDaV, GRAV and SPLSV group with the poleroviruses; BYDV-SGV with the luteoviruses and BLRV with SbDV. The CP sequence of BYDV-RMV forms a distinct branch from PEMV-1 and the other luteoviruses.
Viruses in the family Luteoviridae have replication-related proteins which are sufficiently similar to those in other genera to suggest evolutionary relationships. The putative luteovirus polymerases resemble those of members of the family Tombusviridae. In contrast, polymerases of poleroviruses and enamoviruses resemble those of viruses in the genus Sobemovirus. These polymerase types are thought to be very distant in evolutionary terms and it has been suggested that the origin of these genomes was recombination between ancestral genomes containing the CP genes characteristic of the family Luteoviridae and genomes containing either of the two polymerase types.
Enamo: sigla from Pea enation mosaic virus.
Luteo: from latin luteus, “yellow”.
Polero: sigla from Potato leaf roll virus.
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