Genus: Macluravirus

Genus: Macluravirus

Distinguishing features

Macluraviruses resemble members of the genus Potyvirus in their transmission by aphids but virions are slightly shorter. Macluravirus genome structure is distinguished by (1) a shorter genome by the absence of P1 protein-coding region and a shorter HC-Pro; and (2) the absence of the aphid-transmission motif DAG in CP region (Kondo and Fujita 2012). Macluraviruses form a distinct group in phylogenetic analyses and have different polyprotein consensus cleavage sites.

Virion

Morphology

Virions are flexuous filaments mostly 650–675 nm×13–16 nm.

Physicochemical and physical properties

Virion Sedimentation coefficient S20,w is 155–158S; density in CsCl is 1.31–1.33 g cm−3.

Nucleic acid

Virions contain one molecule of linear positive-sense, ssRNA of about 8.0 kb.

Proteins

Macluraviruses have a single coat (capsid) protein (CP) of 33–34 kDa.

Genome organization and replication

The complete genome sequences of eight different macluraviruses are available. The aa sequences of macluravirus CPs show limited (14–23%) identity with CP sequences of some aphid-transmitted potyviruses. Macluraviruses show significant aa sequence identity in portions of the replicase protein with viruses in other genera of the family Potyviridae. The macluraviruses seem to have a genome organization and replication strategy typical of viruses in the family Potyviridae (Figure 2.Potyviridae), except that they lack the P1 coding region (Figure 1.Macluravirus). 

 

Figure 1.Macluravirus. Schematic diagram of the Chinese yam necrotic mosaic virus (CYNMV) genome. The polyprotein ORF is indicated by the large open box divided into putative mature proteins. The pretty interesting Potyviridae protein (PIPO) is represented by a small box. The untranslated regions (UTR) are represented by lines on each end of the large ORF. Activities of mature proteins are postulated by analogy with genus Potyvirus. Conventions are as for the potyvirus genome organization map (Figure 2.Potyviridae). CYNMV lacks a P1 cistron and has a shorter HC-Pro cistron than most potyviruses. Not to scale.

Biology

Host range

Current information suggests that most viruses have a narrow host range, infecting species in up to nine host families.

Transmission

The viruses are transmitted by aphids in a non-persistent manner and experimentally by mechanical inoculation.

Antigenicity

Moderately immunogenic. No serological relationships to members of the genus Potyvirus have been found except for a weak reaction between maclura mosaic virus and bean yellow mosaic virus.

Species demarcation criteria

See discussion under family description.

Member species

Exemplar isolate of the species
SpeciesVirus nameIsolateAccession numberRefSeq numberAvailable sequenceVirus Abbrev.
Alpinia mosaic virusAlpinia mosaic virusTWAF499025NC_043132Partial genomeAlpMV
Alpinia oxyphylla mosaic virusAlpinia oxyphylla mosaic virusAlpoMG978107NC_055493Complete genomeAloMV
Artichoke latent virusartichoke latent virusFR37KP405232NC_026759Complete genomeArLV
Artichoke latent virusRanunculus latent virusRN128DQ152193Partial genomeRanLV
Broad-leafed dock virus Abroad-leafed dock virus Aab032 AucklandKU053507NC_038560Complete genomeBDVA
Cardamom mosaic viruscardamom mosaic virusKSMF622947NC_039088Complete genomeCdMV
Chinese yam necrotic mosaic virusChinese yam necrotic mosaic virusPES3AB710145NC_018455Complete genomeCYNMV
Maclura mosaic virusMaclura mosaic virusUKU58771NC_043133Partial genomeMacMV
Narcissus latent virusNarcissus latent virusNZDQ450199NC_043134Partial genomeNLV
Yam chlorotic mosaic virusyam chlorotic mosaic virusYSKT724961NC_038561Complete genomeYCMV
Yam chlorotic necrosis virusyam chlorotic necrosis virusY-JishMG755240NC_055491Complete genomeYCNV

Virus names, the choice of exemplar isolates and virus abbreviations are not official ICTV designations.

Related, unclassified viruses

Virus name

Accession number

Virus abbreviation

large cardamom chirke virus

JN257715*

 LCCV

Virus names and virus abbreviations are not official ICTV designations.
* incomplete genome sequence