Interspecies Comparative Analyses Reveal Distinct Carbohydrate-Responsive Systems among Drosophila Species

Abstract

Highlights d The generalists adapt to various nutrient balances, whereas the specialists cannot d The generalists regulate carbohydrate-responsive gene expression by Activin signaling d The specialist species are defective in carbohydrateresponsive gene regulation d The specialist D. sechellia accumulates various metabolites and reduces adaptation

Divergence of Drosophila species: Longevity and reproduction under different nutrient balances

“…In this study, we examined life spans and egg laying of two generalists and three specialists under the two different dietary conditions, the carbohydrate-rich M diet and the proteinrich P diet. One principal finding from this study is that the diet to which larvae of each specialist species has adapted (Watanabe et al, 2019) ensures a longer life span of adult males of that same species (Figure 1c-f). For example, D. melanogaster larvae adapt to both M and P diets equally and there was no dramatic difference in the life span of adult males (Figure 1c).…”

“…Approaches toward identification of causative loci on the D. sechellia genome have just begun (Melvin et al, 2018). Our previous analysis also suggests that D. sechellia may have a defect in TGF-β/activin signaling and additional defects in unidentified adaptive systems (Watanabe et al, 2019). This is partly because the phenotypes of D. sechellia and D. elegans larvae are very similar to those of D. melanogaster mutants of…”

“…We previously carried out comparative analyses of gene expression and metabolism in male larvae of individual species on the two diets (Watanabe et al, 2019). On the M diet, the generalist D. melanogaster controls expression of various metabolic genes, maintains metabolic homeostasis and successfully adapts to the carbohydrate-rich diet.…”

“…diet ("Pupariation rate" in Table 1; Watanabe et al, 2019). Therefore, adult males of each specialist live longer on the diet to which its larvae are better adapted ("Life span" in "Between diets" in Table 1).…”

“…studies of gene expression, metabolism and adaptations under various controlled dietary conditions (Markow & O'Grady, 2007;Matzkin, Johnson, Paight, Bozinovic, & Markow, 2011;Melvin et al, 2018;Nazario-Yepiz, Loustalot-Laclette, Carpinteyro-Ponce, Abreu-Goodger, & Markow, 2017). To study how the generalists adapt to diversified diets and achieve consistent growth milestones, we recently compared adaptability of larvae, including pupariation rates of larvae, of five Drosophila species to diets with distinct nutrient balances (Watanabe et al, 2019). The species comprise two generalists, D. melanogaster and D. simulans, which breed on various fruits and vegetables, and three specialists, D. sechellia, D. elegans and D. erecta, which reproduce on specific fruits or flowers ( Figure 1a and Table 1; Hirai & Kimura, 1997;Markow & O'Grady, 2008;Rio, Couturier, Lemeunier, & Lachaise, 1983;Tsacas & Bächli, 1981).…”