Limits...
The impact of host diet on Wolbachia titer in Drosophila.

Serbus LR, White PM, Silva JP, Rabe A, Teixeira L, Albertson R, Sullivan W - PLoS Pathog. (2015)

Bottom Line: Furthermore, genetic ablation of insulin-producing cells located in the Drosophila brain abolished the yeast impact on oocyte titer.Furthermore, dietary yeast increased somatic Wolbachia titer overall, though not in the central nervous system.These findings highlight the interactions between Wolbachia and germline cells as strongly nutrient-sensitive, and implicate conserved host signaling pathways by which nutrients influence Wolbachia titer.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological Sciences, Florida International University Modesto A. Maidique Campus, Miami, Florida, United States of America; Biomolecular Sciences Institute, Florida International University Modesto A. Maidique Campus, Miami, Florida, United States of America.

ABSTRACT
While a number of studies have identified host factors that influence endosymbiont titer, little is known concerning environmental influences on titer. Here we examined nutrient impact on maternally transmitted Wolbachia endosymbionts in Drosophila. We demonstrate that Drosophila reared on sucrose- and yeast-enriched diets exhibit increased and reduced Wolbachia titers in oogenesis, respectively. The yeast-induced Wolbachia depletion is mediated in large part by the somatic TOR and insulin signaling pathways. Disrupting TORC1 with the small molecule rapamycin dramatically increases oocyte Wolbachia titer, whereas hyper-activating somatic TORC1 suppresses oocyte titer. Furthermore, genetic ablation of insulin-producing cells located in the Drosophila brain abolished the yeast impact on oocyte titer. Exposure to yeast-enriched diets altered Wolbachia nucleoid morphology in oogenesis. Furthermore, dietary yeast increased somatic Wolbachia titer overall, though not in the central nervous system. These findings highlight the interactions between Wolbachia and germline cells as strongly nutrient-sensitive, and implicate conserved host signaling pathways by which nutrients influence Wolbachia titer.

No MeSH data available.


Related in: MedlinePlus

Host diet significantly impacts Wolbachia titer in Drosophila oogenesis.Stage 10A oocytes are outlined in red. Propidium iodide indicates Drosophila nuclei as large circles and Wolbachia as small puncta. A) D. melanogaster oocyte exposed to standard fly food. B) D. melanogaster oocyte exposed to yeast paste. Graphs indicate the average number of Wolbachia nucleoids within single focal planes of stage 10A oocytes. C) Oocyte Wolbachia titer comparison between control food and yeast paste conditions. D) Wolbachia titer response in D. melanogaster to 1:3 dilutions of water, corn syrup (CS), or yeast paste into standard food. Scale bar: 50 μm.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4380406&req=5

ppat.1004777.g002: Host diet significantly impacts Wolbachia titer in Drosophila oogenesis.Stage 10A oocytes are outlined in red. Propidium iodide indicates Drosophila nuclei as large circles and Wolbachia as small puncta. A) D. melanogaster oocyte exposed to standard fly food. B) D. melanogaster oocyte exposed to yeast paste. Graphs indicate the average number of Wolbachia nucleoids within single focal planes of stage 10A oocytes. C) Oocyte Wolbachia titer comparison between control food and yeast paste conditions. D) Wolbachia titer response in D. melanogaster to 1:3 dilutions of water, corn syrup (CS), or yeast paste into standard food. Scale bar: 50 μm.

Mentions: Nutrient availability strongly affects the life cycle of cultured bacteria, raising questions about how host nutrient conditions affect intracellular Wolbachia bacteria. As D. melanogaster in nature preferentially consume yeast [40–45], we tested the effect of dietary yeast on Wolbachia titer in vivo. Female flies were aged first for two days on standard food, then fed yeast paste for 3 days, and examined for Wolbachia titer in oogenesis. Ovarian tissues were stained with propidium iodide to label Wolbachia DNA, and the Wolbachia nucleoids imaged in oocytes of stage 10 egg chambers by confocal microscopy [38]. This analysis demonstrated that yeast paste-fed oocytes carried far less Wolbachia than control oocytes (Fig. 2A-B) (S1 Table). Wolbachia were further quantified within single oocyte focal planes to determine relative titer for each condition [32]. This revealed that Wolbachia titer in yeast paste-fed oocytes was at 27% of the control level. Oocytes treated with standard fly food exhibited an average of 229 +/- 21.1 Wolbachia puncta (n = 30), as compared to yeast paste-fed oocytes that carried 62.6 +/- 4.33 Wolbachia (n = 29) (p < 0.001) (Fig. 2C). This indicates that host exposure to yeast paste significantly reduces Wolbachia titer in oogenesis.


The impact of host diet on Wolbachia titer in Drosophila.

Serbus LR, White PM, Silva JP, Rabe A, Teixeira L, Albertson R, Sullivan W - PLoS Pathog. (2015)

Host diet significantly impacts Wolbachia titer in Drosophila oogenesis.Stage 10A oocytes are outlined in red. Propidium iodide indicates Drosophila nuclei as large circles and Wolbachia as small puncta. A) D. melanogaster oocyte exposed to standard fly food. B) D. melanogaster oocyte exposed to yeast paste. Graphs indicate the average number of Wolbachia nucleoids within single focal planes of stage 10A oocytes. C) Oocyte Wolbachia titer comparison between control food and yeast paste conditions. D) Wolbachia titer response in D. melanogaster to 1:3 dilutions of water, corn syrup (CS), or yeast paste into standard food. Scale bar: 50 μm.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4380406&req=5

ppat.1004777.g002: Host diet significantly impacts Wolbachia titer in Drosophila oogenesis.Stage 10A oocytes are outlined in red. Propidium iodide indicates Drosophila nuclei as large circles and Wolbachia as small puncta. A) D. melanogaster oocyte exposed to standard fly food. B) D. melanogaster oocyte exposed to yeast paste. Graphs indicate the average number of Wolbachia nucleoids within single focal planes of stage 10A oocytes. C) Oocyte Wolbachia titer comparison between control food and yeast paste conditions. D) Wolbachia titer response in D. melanogaster to 1:3 dilutions of water, corn syrup (CS), or yeast paste into standard food. Scale bar: 50 μm.
Mentions: Nutrient availability strongly affects the life cycle of cultured bacteria, raising questions about how host nutrient conditions affect intracellular Wolbachia bacteria. As D. melanogaster in nature preferentially consume yeast [40–45], we tested the effect of dietary yeast on Wolbachia titer in vivo. Female flies were aged first for two days on standard food, then fed yeast paste for 3 days, and examined for Wolbachia titer in oogenesis. Ovarian tissues were stained with propidium iodide to label Wolbachia DNA, and the Wolbachia nucleoids imaged in oocytes of stage 10 egg chambers by confocal microscopy [38]. This analysis demonstrated that yeast paste-fed oocytes carried far less Wolbachia than control oocytes (Fig. 2A-B) (S1 Table). Wolbachia were further quantified within single oocyte focal planes to determine relative titer for each condition [32]. This revealed that Wolbachia titer in yeast paste-fed oocytes was at 27% of the control level. Oocytes treated with standard fly food exhibited an average of 229 +/- 21.1 Wolbachia puncta (n = 30), as compared to yeast paste-fed oocytes that carried 62.6 +/- 4.33 Wolbachia (n = 29) (p < 0.001) (Fig. 2C). This indicates that host exposure to yeast paste significantly reduces Wolbachia titer in oogenesis.

Bottom Line: Furthermore, genetic ablation of insulin-producing cells located in the Drosophila brain abolished the yeast impact on oocyte titer.Furthermore, dietary yeast increased somatic Wolbachia titer overall, though not in the central nervous system.These findings highlight the interactions between Wolbachia and germline cells as strongly nutrient-sensitive, and implicate conserved host signaling pathways by which nutrients influence Wolbachia titer.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological Sciences, Florida International University Modesto A. Maidique Campus, Miami, Florida, United States of America; Biomolecular Sciences Institute, Florida International University Modesto A. Maidique Campus, Miami, Florida, United States of America.

ABSTRACT
While a number of studies have identified host factors that influence endosymbiont titer, little is known concerning environmental influences on titer. Here we examined nutrient impact on maternally transmitted Wolbachia endosymbionts in Drosophila. We demonstrate that Drosophila reared on sucrose- and yeast-enriched diets exhibit increased and reduced Wolbachia titers in oogenesis, respectively. The yeast-induced Wolbachia depletion is mediated in large part by the somatic TOR and insulin signaling pathways. Disrupting TORC1 with the small molecule rapamycin dramatically increases oocyte Wolbachia titer, whereas hyper-activating somatic TORC1 suppresses oocyte titer. Furthermore, genetic ablation of insulin-producing cells located in the Drosophila brain abolished the yeast impact on oocyte titer. Exposure to yeast-enriched diets altered Wolbachia nucleoid morphology in oogenesis. Furthermore, dietary yeast increased somatic Wolbachia titer overall, though not in the central nervous system. These findings highlight the interactions between Wolbachia and germline cells as strongly nutrient-sensitive, and implicate conserved host signaling pathways by which nutrients influence Wolbachia titer.

No MeSH data available.


Related in: MedlinePlus