Nora Virus VP4b and <i>ORF1</i> Circulate in Hemolymph of Infected <i>D. melanogaster</i> with Coordinate Expression of Vago and Vir-1

Study of the novel RNA virus, Nora virus, which is a persistent, picorna-like virus that replicates in the gut of <i>Drosophila melanogaster</i> offers insight into human innate immunity and other picorna-like viruses. Nora virus infection leads to a locomotor abnormality and upregulatio...

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Bibliographic Details
Main Authors: Amanda Macke, Wilfredo Lopez, Darby J. Carlson, Kimberly A. Carlson
Format: Article
Language:English
Published: MDPI AG 2020-08-01
Series:Vaccines
Subjects:
Online Access:https://www.mdpi.com/2076-393X/8/3/491
Description
Summary:Study of the novel RNA virus, Nora virus, which is a persistent, picorna-like virus that replicates in the gut of <i>Drosophila melanogaster</i> offers insight into human innate immunity and other picorna-like viruses. Nora virus infection leads to a locomotor abnormality and upregulation of two candidate target proteins, Vago and Virus-induced RNA 1 (Vir-1). These proteins are uncharacterized in response to Nora virus. We hypothesize that Nora virus is circulating in the hemolymph of Nora virus-infected <i>D. melanogaster</i>, allowing for migration beyond the primary site of replication in the gut. Analysis by qRT-PCR demonstrated biphasic viral load and corresponding <i>vago</i> and <i>vir-1</i> transcription levels, suggesting transcription of <i>vago</i> and <i>vir-1</i> occurs in response to viral infection. However, Vir-1 is also present in virus-free <i>D. melanogaster</i> suggesting basal expression or alternative functions. Presence of Nora virus RNA and the Viral Protein 4b (VP4b), in hemolymph of infected <i>D. melanogaster</i> supports the hypothesized circulation of Nora virus in the hemolymph. The study suggests that impaired locomotor function may be due to transport of Nora virus from the gut to the brain via the hemolymph.
ISSN:2076-393X