The transcriptional response of Drosophila melanogaster to infection with the sigma virus (Rhabdoviridae).
BACKGROUND
Bacterial and fungal infections induce a potent immune response in Drosophila melanogaster, but it is unclear whether viral infections induce an antiviral immune response. Using microarrays, we examined the changes in gene expression in Drosophila that occur in response to infection with the sigma virus, a negative-stranded RNA virus (Rhabdoviridae) that occurs in wild populations of D. melanogaster.


RESULTS
We detected many changes in gene expression in infected flies, but found no evidence for the activation of the Toll, IMD or Jak-STAT pathways, which control immune responses against bacteria and fungi. We identified a number of functional categories of genes, including serine proteases, ribosomal proteins and chorion proteins that were overrepresented among the differentially expressed genes. We also found that the sigma virus alters the expression of many more genes in males than in females.


CONCLUSIONS
These data suggest that either Drosophila do not mount an immune response against the sigma virus, or that the immune response is not controlled by known immune pathways. If the latter is true, the genes that we identified as differentially expressed after infection are promising candidates for controlling the host's response to the sigma virus.
Carpenter
Jennifer
J
Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom. jenny@jennycarpenter.com
Hutter
Stephan
S
Baines
John F
JF
Roller
Julia
J
Saminadin-Peter
Sarah S
SS
Parsch
John
J
Jiggins
Francis M
FM
D000818:Animals; D001483:Base Sequence; D017931:DNA Primers; D015536:Down-Regulation; D004331:Drosophila melanogaster / Q000235:genetics* / Q000276:immunology / Q000821:virology; D005260:Female; D008297:Male; D016133:Polymerase Chain Reaction; D012209:Rhabdoviridae / Q000472:pathogenicity*; D015854:Up-Regulation
D017931:DNA Primers