The Bacterial Symbiont Wolbachia Induces Resistance to RNA Viral Infections in Drosophila melanogaster
Figure 4
Wolbachia Interaction with Other Viruses
(A) RT-PCR was done with Nora virus primers on RNA of VF-0058–3, VF-0058–3t, and Oregon R flies (left). PCR with RpL32 was done as control. Three–six-d-old males of VF-0058–3 and VF-0058–3t lines were injected with a virus extract of Oregon R flies and collected 3 d later. RNA was extracted and RT-PCR done with primers for Nora virus and RpL32. The same number of PCR cycles was done for both samples. The assay was repeated three more times, from infection of flies with virus extract, with similar results.
(B) Fifty 3–6-d-old males, per sample, of VF-0058–3 and VF-0058–3t lines were injected with 50 TCID50 FHV, and their survival was followed daily. The assay was repeated twice with males and once with females with similar results.
(C) Extracts of VF-0058–3 and VF-0058–3t flies 3, 6, and 9 d after injection with 50 TCID50 FHV or not injected were probed in a Western blot with anti-FHV. Anti-tubulin was used as a loading control.
(D) Titration, in cell culture, of FHV levels per fly of VF-0058–3 and VF-0058–3t flies 6 d after injection with 50 TCID50 FHV. Squares are replicates (10 per sample), lines are geometric means of replicates. Virus titres in VF-0058–3 and VF-0058–3t are not significantly different (Mann-Whitney test, p = 0.05764).
(E) Fifty 3–6-d-old males, per sample, of VF-0058–3 and VF-0058–3t lines were injected with 1,000 TCID50 IIV-6 or buffer, and their survival followed. The assay was repeated once with males and the IIV-6 injected flies survival curves were also repeated with females, with similar results.
(F) Iridescent-infected male 20 d after injection with 1000 TCID50 IIV-6 (right) and not infected same age male (left) are shown.
(G) Titration, in cell culture, of IIV-6 levels per fly of VF-0058–3 and VF-0058–3t flies 10 days after injection with 1000 TCID50 IIV-6. Squares are replicates (10 per sample), lines are geometric means of replicates. Virus titres in VF-0058–3 and VF-0058–3t are not significantly different (Mann-Whitney test, p = 0.08118).