Family: Leishbuviridae

Scott Adkins, Katherine Brown, Juan Carlos de la Torre, Michele Digiaro, Holly R. Hughes, Sandra Junglen, Amy J. Lambert, Piet Maes, Marco Marklewitz, Gustavo Palacios, Takahide Sasaya (笹谷孝英), Massimo Turina, Yong-Zhen Zhang (张永振), and Jens H. Kuhn

*The citation for this ICTV Report chapter is the summary to be published as Adkins et al., (2023):

ICTV Virus Taxonomy Profile: Leishbuviridae, Journal of General Virology 2023, (in press)

Corresponding author: Jens H. Kuhn (kuhnjens@mail.nih.gov) 
Edited by: Jens H. Kuhn and Stuart G. Siddell
Posted: November 2023

Summary

Leishbuviridae is a family of negative-sense RNA viruses with genomes of about 8.0 kb (Table 1.Leishbuviridae). These viruses have been found in protists. The family includes a single genus with one species for one virus. The leishbuvirid genome consists of three monocistronic RNA segments with open reading frames (ORFs) that encode a nucleoprotein (NP), a glycoprotein (GP), and a large (L) protein containing an RNA-directed RNA polymerase (RdRP) domain.

Table 1.Leishbuviridae. Characteristics of members of the family Leishbuviridae

Virion

Morphology

Unknown

Nucleic acid

Leishbuvirids have three RNA segments (small [S], medium [M], and large [L]) of linear negative-sense RNA with a total length of about 8.0 kb (S segment: 0.7–0.8 kb; M segment: about 1.2 kb; and L segment: about 6.0 kb) (Akopyants et al., 2016, Grybchuk et al., 2018a).

Genome organization and replication

Viruses of the family Leishbuviridae have a tri-segmented genome with three ORFs that encode an NP, a GP, and an L protein containing an RdRP domain (Akopyants et al., 2016) (Figure 1.Leishbuviridae).

Figure 1.Leishbuviridae. Genome organization of Leptomonas moramango virus. ORFs are colored according to the predicted protein function (GP, glycoprotein gene; L, large protein gene; NP, nucleoprotein gene).

Biology

The only classified leishbuvirid, Leptomonas moramango virus (LEPMV), was detected in kinetoplastean protists (trypanosomatid Leptomonas moramango Yurchenko et al., 2014) in Madagascar (Akopyants et al., 2016).

Unclassified leishbuvirids have been detected in (protists of) dipteran insects, such as culicid mosquitoes (Culex quinquefasciatus Say, 1823 in Zambia [unpublished, L: LC772153; L: LC772154; L: LC772155; L: OL700099; L: OL700101; L: OL700102; L: OL700112] and Ochlerotatus communis (de Geer, 1776) in Sweden (Ortiz-Baez et al., 2022)), unspecified phorid and tephritid fruit flies (Bactrocera correcta (Bezzi, 1916)) in China (Li et al., 2015, Grybchuk et al., 2018a, Zhang et al., 2022), ephydrid shore flies in China (Hydrellia griseola (Fallén, 1913)) (unpublished, L: MZ209735), and sarcophagid flesh flies in Australia (Mahar et al., 2020); in hymenopteran insects, such as bumblebees (apid Bombus spp.) (Klocek et al., 2023), honeybees (apid Apis mellifera Linnaeus, 1758) in South Africa and the USA (Remnant et al., 2017, Grybchuk et al., 2018a); in brown salor spiders (araneid Neoscona nautica (L. Koch, 1875)) in China (Li et al., 2015, Grybchuk et al., 2018a); in leeches in China (Shi et al., 2016, Grybchuk et al., 2018a); and directly in kinetoplastean protists (trypanosomatid Blechomonas sp, Crithidia sp., Leptomonas sp., and Phytomonas sp.) in the Czech Republic, Ecuador, and Madagascar (Akopyants et al., 2016, Grybchuk et al., 2018a, Grybchuk et al., 2018b, Grybchuk et al., 2020, Neri et al., 2022, Macedo et al., 2023, Mendes Junior et al., 2023).

Derivation of names

Leishbuviridae: a portmanteau of Leishmania and bunyavirus, referring to a genus of Trypanosomatidae, that includes the host of isolation of Leptomonas moramango virus , and the order Bunyavirales, which includes the virus family

leptomonadis: from the host genus Leptomonas

Shilevirus: scrambled from Leishmania

Genus demarcation criteria

Not applicable (the family includes only a single genus).

Species demarcation criteria

Not applicable (the only genus includes only a single species).

Relationships within the family

Not applicable (the only genus includes only a single species).

Relationships with other taxa

Phylogenetic relationships of members of the family Leishbuviridae are shown in Figure 2.Leishbuviridae. Viruses in the family Leishbuviridae are most closely related to bunyaviral arenavirids, discoviridae, mypovirids, nairovirids, phenuivirids, and wupedevirids (Huang et al., 2019, Herath et al., 2020).

Figure 2.Leishbuviridae. Phylogenetic relationships of Leptomonas moramango virus with other members of the order Bunyavirales. L protein sequences were aligned using MUSCLE and a maximum likelihood tree was produced using FastTree with default settings. Branches are collapsed for members of families apart from Leishbuviridae. Numbers at nodes indicated bootstrap support > 70%.

Related, unclassified viruses

Virus names and virus abbreviations are not official ICTV designations.

* Incomplete genome