Morphological and Molecular Characterization of a Cypovirus ( Reoviridae ) from the Mosquito Uranotaenia sapphirina (Diptera: Culicidae)

Abstract

A novel cypovirus has been isolated from the mosquito Uranotaenia sapphirina (UsCPV) and shown to cause a chronic infection confined to the cytoplasm of epithelial cells of the gastric ceca and posterior stomach. The production of large numbers of virions and inclusion bodies and their arrangement into paracrystalline arrays gives the gut of infected insects a distinctive blue iridescence. The virions, which were examined by electron microscopy, are icosahedral (55 to 65 nm in diameter) with a central core that is surrounded by a single capsid layer. They are usually packaged individually within cubic inclusion bodies (polyhedra, ϳ100 nm across), although two to eight virus particles were sometimes occluded together. The virus was experimentally transmitted per os to several mosquito species. The transmission rate was enhanced by the presence of magnesium ions but was inhibited by calcium ions. Most of the infected larvae survived to adulthood, and the adults retained the infection. Electrophoretic analysis of the UsCPV genome segments (using 1% agarose gels) generated a migration pattern (electropherotype) that is different from those of the 16 Cypovirus species already recognized. UsCPV genome segment 10 (Seg-10) showed no significant nucleotide sequence similarity to the corresponding segment of the other cypoviruses that have previously been analyzed, and it has different "conserved" termini. A BLAST search of the UsCPV deduced amino acid sequence also showed little similarity to Antheraea mylitta CPV-4 (67 of 290 [23%]) or Choristoneura fumiferana CPV-16 (33 of 111 [29%]). We conclude that UsCPV should be recognized as a member of a new Cypovirus species (Cypovirus 17, strain UsCPV-17).

A New Flavivirus and a New Vector: Characterization of a Novel Flavivirus Isolated from Uranotaenia Mosquitoes from a Tropical Rain Forest

“…Less is known about the host range of this mosquito genus, but among the few anthropophilic species, none are known to transmit pathogens (29,30). The only virus described is a cypovirus (Reoviridae) isolated from Uranotaenia sapphirina (31). Thus, the isolation of a novel flavivirus that clusters within the mosquito-borne viruses from Uranotaenia mashonaensis indicates that mosquitoes of this genus may also be involved in pathogen transmission.…”

Insecticidal Efficacy of Azadirachta indica, Nucleopolyhedrovirus and Chlorantraniliprole Singly or Combined against Field Populations fo Helicoverpa armigera Hübner (Lepidoptera: Noctuidae)

“…To recover the purified virus, the second instar larvae of H. armigera were infected with a suspension of NPV by spraying and the larvae were allowed to feed on artificial diet (Wakil et al, 2011) for 7 d. Then the midguts of the infected cadavers were homogenized in deionized water, filtered through muslin cloth and centrifuged at 16 000 rpm for 45 min (Shapiro et al, 2005;Green et al, 2006). The purified virus was given washes three times in distilled water, and held in 0.1 mM NaOH at 5 °C.…”

Structure and function of S9 segment of grass carp reovirus Anhui strain

“…Although the first AUG of S9 segment appears to be not in a very favorable context for initiation of translation (UGUAUGG) according to the consensus sequence (A/G)NNAUGG (N = any nucleoside), in most cases, the AUG nearest the 5 0 -terminal cap is exclusively used for initiation for protein synthesis in a ''scanning model'' [15,16]. The putative methionine start codon (nucleotides [23][24][25] is thus the first triplet rather than the others.…”

“…Amplification of the entire S9 segment was conducted using the full-length amplification of cDNA (FLAC) technique [21,25]. Online services (http://blast.ncbi.nlm.…”