Successful introgression of wMel Wolbachia into Aedes aegypti populations in Fiji, Vanuatu and Kiribati.

Pacific Island countries have experienced periodic dengue, chikungunya and Zika outbreaks for decades. The prevention and control of these mosquito-borne diseases rely heavily on control of Aedes aegypti mosquitoes, which in most settings are the primary vector. Introgression of the intracellular bacterium Wolbachia pipientis (wMel strain) into Ae.

Antiviral strains associate with endoplasmic reticulum membranes and induce lipid droplet formation to restrict dengue virus replication.

are a genus of insect endosymbiotic bacteria which includes strains Mel and AlbB that are being utilized as a biocontrol tool to reduce the incidence of -transmitted viral diseases like dengue. However, the precise mechanisms underpinning the antiviral activity of these strains are not well defined. Here, we generated a panel of -derived cell lines infected with antiviral strains Mel and AlbB or the non-antiviral strain Pip to understand host cell morphological changes specifically induced by antiviral strains.

Enhancing the scalability of Wolbachia-based vector-borne disease management: time and temperature limits for storage and transport of Wolbachia-infected Aedes aegypti eggs for field releases.

Background: Introgression of the bacterial endosymbiont Wolbachia into Aedes aegypti populations is a biocontrol approach being used to reduce arbovirus transmission. This requires mass release of Wolbachia-infected mosquitoes. While releases have been conducted using a variety of techniques, egg releases, using water-soluble capsules containing mosquito eggs and larval food, offer an attractive method due to its potential to reduce onsite resource requirements.

Transient Introgression of into Populations Does Not Elicit an Antibody Response to Surface Protein in Community Members.

is an endosymbiotic bacterium that can restrict the transmission of human pathogenic viruses by mosquitoes. Recent field trials have shown that dengue incidence is significantly reduced when is introgressed into the local population. Female are anautogenous and feed on human blood to produce viable eggs.

Trash to Treasure: How Insect Protein and Waste Containers Can Improve the Environmental Footprint of Mosquito Egg Releases.

Release and subsequent establishment of -infected in native mosquito populations has successfully reduced mosquito-borne disease incidence. While this is promising, further development is required to ensure that this method is scalable and sustainable. Egg release is a beneficial technique that requires reduced onsite resources and increases community acceptance; however, its incidental ecological impacts must be considered to ensure sustainability.

Assessment of fitness and vector competence of a New Caledonia wMel Aedes aegypti strain before field-release.

Background: Biological control programs involving Wolbachia-infected Aedes aegypti are currently deployed in different epidemiological settings. New Caledonia (NC) is an ideal location for the implementation and evaluation of such a strategy as the only proven vector for dengue virus (DENV) is Ae. aegypti and dengue outbreaks frequency and severity are increasing.

Mel genome remains stable after 7 years in Australian field populations.

Infection of Mel in imparts two signature features that enable its application for biocontrol of dengue. First, the susceptibility of mosquitoes to viruses such as dengue and Zika is reduced. Second, a reproductive manipulation is caused that enables Mel introgression into wild-type mosquito populations.

Using to Eliminate Dengue: Will the Virus Fight Back?

Recent field trials have demonstrated that dengue incidence can be substantially reduced by introgressing strains of the endosymbiotic bacterium into Aedes aegypti mosquito populations. This strategy relies on reducing the susceptibility of to disseminated infection by positive-sense RNA viruses like dengue. However, RNA viruses are well known to adapt to antiviral pressures.

Deleterious Impact on Egg Development: The Potential Role of Nutritional Parasitism.

The artificial introduction of the endosymbiotic bacterium, into mosquitoes reduces the ability of mosquitoes to transmit human pathogenic viruses and is now being developed as a biocontrol tool. Successful introgression of -carrying into native mosquito populations at field sites in Australia, Indonesia and Malaysia has been associated with reduced disease prevalence in the treated community. In separate field programs, is also being used as a mosquito population suppression tool, where the release of male only -infected prevents the native mosquito population from producing viable eggs, subsequently suppressing the wild population.

Modulation of acyl-carnitines, the broad mechanism behind -mediated inhibition of medically important flaviviruses in .

-infected mosquitoes are refractory to flavivirus infections, but the role of lipids in -mediated virus blocking remains to be elucidated. Here, we use liquid chromatography mass spectrometry to provide a comprehensive picture of the lipidome of cells infected with only, either dengue or Zika virus only, and -infected cells superinfected with either dengue or Zika virus. This approach identifies a class of lipids, acyl-carnitines, as being down-regulated during infection.

Novel phenotype of Wolbachia strain wPip in Aedes aegypti challenges assumptions on mechanisms of Wolbachia-mediated dengue virus inhibition.

The bacterial endosymbiont Wolbachia is a biocontrol tool that inhibits the ability of the Aedes aegypti mosquito to transmit positive-sense RNA viruses such as dengue and Zika. Growing evidence indicates that when Wolbachia strains wMel or wAlbB are introduced into local mosquito populations, human dengue incidence is reduced. Despite the success of this novel intervention, we still do not fully understand how Wolbachia protects mosquitoes from viral infection.

Multiple Wolbachia strains provide comparative levels of protection against dengue virus infection in Aedes aegypti.

The insect bacterium Wolbachia pipientis is being introgressed into Aedes aegypti populations as an intervention against the transmission of medically important arboviruses. Here we compare Ae. aegypti mosquitoes infected with wMelCS or wAlbB to the widely used wMel Wolbachia strain on an Australian nuclear genetic background for their susceptibility to infection by dengue virus (DENV) genotypes spanning all four serotypes.

Differential suppression of persistent insect specific viruses in trans-infected wMel and wMelPop-CLA Aedes-derived mosquito lines.

Wolbachia suppresses the replication of +ssRNA viruses such as dengue and Zika viruses in Aedes aegypti mosquitoes. However, the range of viruses affected by this endosymbiont is yet to be explored. Recently, novel insect-specific viruses (ISVs) have been described from numerous mosquito species and mosquito-derived cell lines.

Controlling vector-borne diseases by releasing modified mosquitoes.

Aedes mosquito-transmitted diseases, such as dengue, Zika and chikungunya, are becoming major global health emergencies while old threats, such as yellow fever, are re-emerging. Traditional control methods, which have focused on reducing mosquito populations through the application of insecticides or preventing breeding through removal of larval habitat, are largely ineffective, as evidenced by the increasing global disease burden. Here, we review novel mosquito population reduction and population modification approaches with a focus on control methods based on the release of mosquitoes, including the release of Wolbachia-infected mosquitoes and strategies to genetically modify the vector, that are currently under development and have the potential to contribute to a reversal of the current alarming disease trends.

Novel Wolbachia-transinfected Aedes aegypti mosquitoes possess diverse fitness and vector competence phenotypes.

Wolbachia pipientis from Drosophila melanogaster (wMel) is an endosymbiotic bacterium that restricts transmission of human pathogenic flaviviruses and alphaviruses, including dengue, Zika, and chikungunya viruses, when introduced into the mosquito vector Aedes aegypti. To date, wMel-infected Ae. aegypti have been released in field trials in 5 countries to evaluate the effectiveness of this strategy for disease control.

Gut microbiota in Drosophila melanogaster interacts with Wolbachia but does not contribute to Wolbachia-mediated antiviral protection.

Animals experience near constant infection with microorganisms. A significant proportion of these microbiota reside in the alimentary tract. There is a growing appreciation for the roles gut microbiota play in host biology.

The Drosophila bag of marbles Gene Interacts Genetically with Wolbachia and Shows Female-Specific Effects of Divergence.

Many reproductive proteins from diverse taxa evolve rapidly and adaptively. These proteins are typically involved in late stages of reproduction such as sperm development and fertilization, and are more often functional in males than females. Surprisingly, many germline stem cell (GSC) regulatory genes, which are essential for the earliest stages of reproduction, also evolve adaptively in Drosophila.

Adaptive evolution of genes involved in the regulation of germline stem cells in Drosophila melanogaster and D. simulans.

Population genetic and comparative analyses in diverse taxa have shown that numerous genes involved in reproduction are adaptively evolving. Two genes involved in germline stem cell regulation, bag of marbles (bam) and benign gonial cell neoplasm (bgcn), have been shown previously to experience recurrent, adaptive evolution in both Drosophila melanogaster and D. simulans.

Reduced fertility of Drosophila melanogaster hybrid male rescue (Hmr) mutant females is partially complemented by Hmr orthologs from sibling species.

The gene Hybrid male rescue (Hmr) causes lethality in interspecific hybrids between Drosophila melanogaster and its sibling species. Hmr has functionally diverged for this interspecific phenotype because lethality is caused specifically by D. melanogaster Hmr but not by D.

Genotype-by-environment interactions and adaptation to local temperature affect immunity and fecundity in Drosophila melanogaster.

Natural populations of most organisms harbor substantial genetic variation for resistance to infection. The continued existence of such variation is unexpected under simple evolutionary models that either posit direct and continuous natural selection on the immune system or an evolved life history "balance" between immunity and other fitness traits in a constant environment. However, both local adaptation to heterogeneous environments and genotype-by-environment interactions can maintain genetic variation in a species.

Two Dobzhansky-Muller genes interact to cause hybrid lethality in Drosophila.

The Dobzhansky-Muller model proposes that hybrid incompatibilities are caused by the interaction between genes that have functionally diverged in the respective hybridizing species. Here, we show that Lethal hybrid rescue (Lhr) has functionally diverged in Drosophila simulans and interacts with Hybrid male rescue (Hmr), which has functionally diverged in D. melanogaster, to cause lethality in F1 hybrid males.

Recurrent positive selection at bgcn, a key determinant of germ line differentiation, does not appear to be driven by simple coevolution with its partner protein bam.

Surveys of nucleotide sequence polymorphism in Drosophila melanogaster and Drosophila simulans were performed at 2 interacting loci crucial for gametogenesis: bag-of-marbles (bam) and benign gonial cell neoplasm (bgcn). At the polymorphism level, both loci appear to be evolving under the expectations of the neutral theory. However, ratios of polymorphism and divergence for synonymous and nonsynonymous mutations depart significantly from neutral expectations for both loci consistent with a previous observation of positive selection at bam.