The Modulation of the Symbiont/Host Interaction between Wolbachia pipientis and Aedes fluviatilis Embryos by Glycogen Metabolism

Abstract

Wolbachia pipientis, a maternally transmitted bacterium that colonizes arthropods, may affect the general aspects of insect physiology, particularly reproduction. Wolbachia is a natural endosymbiont of Aedes fluviatilis, whose effects in embryogenesis and reproduction have not been addressed so far. In this context, we investigated the correlation between glucose metabolism and morphological alterations during A. fluviatilis embryo development in Wolbachia-positive (W+) and Wolbachia-negative (W−) mosquito strains. While both strains do not display significant morphological and larval hatching differences, larger differences were observed in hexokinase activity and glycogen contents during early and mid-stages of embryogenesis, respectively. To investigate if glycogen would be required for parasite-host interaction, we reduced Glycogen Synthase Kinase-3 (GSK-3) levels in adult females and their eggs by RNAi. GSK-3 knock-down leads to embryonic lethality, lower levels of glycogen and total protein and Wolbachia reduction. Therefore, our results suggest that the relationship between A. fluviatilis and Wolbachia may be modulated by glycogen metabolism.

The transcriptome of the mosquito Aedes fluviatilis (Diptera: Culicidae), and transcriptional changes associated with its native Wolbachia infection

“…aegypti [10, 11, 14], the effect was still broad in scope and encompassed a wide range of biological processes, many of which are held in common with Wolbachia infections in other mosquitoes. Metabolic effects of w Flu infection appear to be particularly prominent [71], especially those associated with protein and lipid metabolism, and it is possible that the strain maintains the characteristic of a Jekyll and Hyde infection by both parasitising and providing key metabolites [26, 99]. And our results suggest that native strains such as w Flu likely have a greater impact on mosquito host biology than previously thought.…”

“…aegypti [11, 38, 70]. Previous work indicates that w Flu infection leads to elevated levels of glycogen [71], a major carbohydrate reserve, in developing embryos. While it is unclear if this effect occurs in adults, we did see elevated levels of β-glucosidase, which encodes an enzyme involved in the breakdown of complex carbohydrates including glycogen.…”

“…The effect on these genes likely arises due to the strong presence of w Flu in the ovaries, and may contribute to further differences in egg nutritional content, as is seen with glycogen [71]. …”

Whole genome screen reveals a novel relationship between Wolbachia levels and Drosophila host translation

“…that Wolbachia relies on several aspects of these broad categories. For example, Wolbachia can alter host iron, carbohydrate and lipid metabolism [72][73][74][75][76]. Further, Wolbachia interacts with host cytoskeleton such as microtubules for transport and host actin [32,34,35,77].…”

Non-Classical Gluconeogenesis-Dependent Glucose Metabolism in Rhipicephalus microplus Embryonic Cell Line BME26

“…Specifically, a GSK3 knockdown (around 90%) in female mosquito Aedes fluviatilis prevented them from developing their ovaries as well as egg laying. So, in a new experiment, GSK3 transcription was reduced by 30% to evaluate the effect of GSK3 inhibition on insect embryogenesis [ 44 ]. Similarly, we induced a higher efficiency in GSK3 silencing in the BME26 cells previously, leading to cell death (data not shown).…”