Genetic characterization, molecular epidemiology, and phylogenetic relationships of insect-specific viruses in the taxon Negevirus

Abstract

The recently described taxon Negevirus is comprised of a diverse group of insect-specific viruses isolated from mosquitoes and phlebotomine sandflies. In this study, a comprehensive genetic characterization, molecular, epidemiological and evolutionary analyses were conducted on nearly full-length sequences of 91 new negevirus isolates obtained in Brazil, Colombia, Peru, Panama, USA and Nepal. We demonstrated that these arthropod restricted viruses are clustered in two major phylogenetic groups with origins related to three plant virus genera (Cilevirus, Higrevirus and Blunevirus). Molecular analyses demonstrated that specific host correlations are not present with most negeviruses; instead, high genetic variability, wide host-range, and cross-species transmission were noted. The data presented here also revealed the existence of five novel insect-specific viruses falling into two arthropod-restrictive virus taxa, previously proposed as distinct genera, designated Nelorpivirus and Sandewavirus. Our results provide a better understanding of the molecular epidemiology, evolution, taxonomy and stability of this group of insect-restricted viruses.

Natural infection by Culex flavivirus in Culex quinquefasciatus mosquitoes captured in Cuiabá, Mato Grosso Mid‐Western Brazil

“…Negevirus ORF1 (756 bp) phylogenetic analysis revealed a major split in two groups, named Nelorpivirus and Sandewavirus , with a different ancestral origin, corroborating previous observations indicating that geography may also play a role in Negevirus evolution and sub‐speciation (Nunes et al , ). Santana and Siriri viruses formed a cluster inside Sandewavirus subgroup, very close to other negeviruses identified in mosquitoes worldwide (Vasilakis et al , ; Kallies et al , ).…”

“…quinquefasciatus in tropical regions (Bittar et al , ). Moreover, the cysteine residues and potential glycosylation sites found in CxFV sequences in the present study are associated with genomic secondary structure maintenance, pathogenicity and viral infectivity in their hosts (Murrell et al , ; Nunes et al , ).…”

Deciphering the Virome of Culex vishnui Subgroup Mosquitoes, the Major Vectors of Japanese Encephalitis, in Japan

“…Negevirus was recently described as a diverse group of ISVs isolated from mosquitoes and phlebotomine sandflies [30]. In this study, two novel negevirus-like sequences were found in C. vishnui subgroup mosquitoes.…”

A decade of RNA virus metagenomics is (not) enough

“…Even when sequencing discrete organisms such as a singular honeybee, the co-existence of eukaryotic parasites means that imputation of viral host cannot be exact (Runckel et al, 2011). Host promiscuity seems to be a common theme among newly-described RNA viruses (Nunes et al, 2017). Highly-indexed libraries, chemical linkage of RNA species, and physical partitioning through single cell transcriptomics currently provide the best potential solution to the host imputation problem in complex mixtures (Burton et al, 2014;Chow et al, 2015;Turner et al, 2009).…”