RESUMO
This report describes and characterizes a novel entomobirnavirus, designated Port Bolivar virus (PTBV), that was isolated from a pool of Aedes sollicitans mosquitoes collected in a saltwater marsh in East Texas, USA. Full genome sequencing and phylogenetic analyses indicate that PTBV is distinct but genetically related to Drosophila X virus and mosquito X virus, which are assigned to species in the genus Entomobirnavirus, family Birnaviridae. PTBV produced cytopathic effect (CPE) in cultures of mosquito (C6/36) cells, but not in Vero cell cultures. Ultrastructural studies of PTBV in infected C6/36 cells demonstrated unenveloped virus particles about 55 nm in diameter.
Assuntos
Aedes/virologia , Entomobirnavirus/classificação , Entomobirnavirus/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Efeito Citopatogênico Viral , Entomobirnavirus/genética , Entomobirnavirus/ultraestrutura , Genoma Viral/genética , Vírus de Insetos/classificação , Vírus de Insetos/genética , Vírus de Insetos/fisiologia , Vírus de Insetos/ultraestrutura , Filogenia , RNA Viral/genética , Especificidade da Espécie , Texas , Vírion/ultraestruturaRESUMO
We investigated whether small RNA (sRNA) sequenced from field-collected mosquitoes and chironomids (Diptera) can be used as a proxy signature of viral prevalence within a range of species and viral groups, using sRNAs sequenced from wild-caught specimens, to inform total RNA deep sequencing of samples of particular interest. Using this strategy, we sequenced from adult Anopheles maculipennis s.l. mosquitoes the apparently nearly complete genome of one previously undescribed virus related to chronic bee paralysis virus, and, from a pool of Ochlerotatus caspius and Oc. detritus mosquitoes, a nearly complete entomobirnavirus genome. We also reconstructed long sequences (1503-6557 nt) related to at least nine other viruses. Crucially, several of the sequences detected were reconstructed from host organisms highly divergent from those in which related viruses have been previously isolated or discovered. It is clear that viral transmission and maintenance cycles in nature are likely to be significantly more complex and taxonomically diverse than previously expected.
Assuntos
Dípteros/virologia , Vírus de Insetos/classificação , Vírus de Insetos/genética , RNA Viral , Animais , Sequência de Bases , Códon , Culicidae/virologia , Entomobirnavirus/classificação , Entomobirnavirus/genética , Mutação da Fase de Leitura , Genoma Viral , Dados de Sequência Molecular , Filogenia , Polimorfismo Genético , Fases de Leitura , Reprodutibilidade dos Testes , Alinhamento de Sequência , Análise de Sequência de DNA , Regiões não TraduzidasRESUMO
Drosophila X virus (DXV), the prototype Entomobirnavirus, is a well-studied RNA virus model. Its origin is unknown, and so is that of the only other entomobirnavirus, Espirito Santo virus (ESV). We isolated an entomobirnavirus tentatively named Culex Y virus (CYV) from hibernating Culex pipiens complex mosquitoes in Germany. CYV was detected in three pools consisting of 11 mosquitoes each. Full-genome sequencing and phylogenetic analyses suggested that CYV and ESV define one sister species to DXV within the genus Entomobirnavirus. In contrast to the laboratory-derived ESV, the ORF5 initiation codon AUG was mutated to (1927)GUG in all three wild-type CYV isolates. Also in contrast to ESV, replication of CYV was not dependent on other viruses in insect cell culture. CYV could provide a wild-type counterpart in research fields relying on DXV and other cell culture-adapted strains.
