Age, tissue, genotype and virus infection regulate Wolbachia levels in Drosophila.
Wolbachia
DCV
FHV
in-situ localization
native host-Wolbachia associations
tissue-tropism
Journal
Molecular ecology
ISSN: 1365-294X
Titre abrégé: Mol Ecol
Pays: England
ID NLM: 9214478
Informations de publication
Date de publication:
06 2020
06 2020
Historique:
received:
20
12
2018
accepted:
28
04
2020
pubmed:
12
5
2020
medline:
5
6
2021
entrez:
12
5
2020
Statut:
ppublish
Résumé
The bacterial symbiont Wolbachia can protect insects against viral pathogens, and the varying levels of antiviral protection are correlated with the endosymbiont load within the insects. To understand why Wolbachia strains differ in their antiviral effects, we investigated the factors controlling Wolbachia density in five closely related strains in their natural Drosophila hosts. We found that Wolbachia density varied greatly across different tissues and between flies of different ages, and these effects depended on the host-symbiont association. Some endosymbionts maintained largely stable densities as flies aged while others increased, and these effects in turn depended on the tissue being examined. Measuring Wolbachia rRNA levels in response to viral infection, we found that viral infection itself also altered Wolbachia levels, with Flock House virus causing substantial reductions in symbiont loads late in the infection. This effect, however, was virus-specific as Drosophila C virus had little impact on Wolbachia in all of the five host systems. Because viruses have strong tissue tropisms and antiviral protection is thought to be cell-autonomous, these effects are likely to affect the virus-blocking phenomenon. However, we were unable to find any evidence of a correlation between Wolbachia and viral titres within the same tissues. We conclude that Wolbachia levels within flies are regulated in a complex host-symbiont-virus-dependent manner and this trinity is likely to influence the antiviral effects of Wolbachia.
Banques de données
Dryad
['10.5061/dryad.mcvdncjxp']
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
2063-2079Subventions
Organisme : Austrian Science Fund FWF
ID : P 28255
Pays : Austria
Informations de copyright
© 2020 John Wiley & Sons Ltd.
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