Males and females typically pursue divergent reproductive strategies and accordingly require different dietary compositions to maximise their fitness. Here we move from identifying sex-specific optimal diets to understanding the molecular mechanisms that underlie male and female responses to dietary variation in Drosophila melanogaster. We examine male and female gene expression on male-optimal (carbohydrate-rich) and female-optimal (protein-rich) diets. We find that the sexes share a large core of metabolic genes that are concordantly regulated in response to dietary composition. However, we also observe smaller sets of genes with divergent and opposing regulation, most notably in reproductive genes which are over-expressed on each sex's optimal diet. Our results suggest that nutrient sensing output emanating from a shared metabolic machinery are reversed in males and females, leading to opposing diet-dependent regulation of reproduction in males and females. Further analysis and experiments suggest that this reverse regulation occurs within the IIS/TOR network.
All data generated or analysed during this study are included in the supplementary datafiles.We compare our results to data from three papers, with results discussed throughout our paper.- Dobson, A.J., He, X., Blanc, E., Bolukbasi, E., Feseha, Y., Yang, M., and Piper, M.D.W. (2018). Tissue-specific transcriptome profiling of Drosophila reveals roles for GATA transcription factors in longevity by dietary restriction. Aging and Mechanisms of Disease 4, 5.- Graze, R.M., Tzeng, R.Y., Howard, T.S., and Arbeitman, M.N. (2018). Perturbation of IIS/TOR signaling alters the landscape of sex-differential gene expression in Drosophila. BMC Genomics 19, 893- Tiebe, M., Lutz, M., De La Garza, A., Buechling, T., Boutros, M., and Teleman, A.A. (2015). REPTOR and REPTOR-BP Regulate Organismal Metabolism and Transcription Downstream of TORC1. Dev Cell 33, 272-284.
Data from: Sex-specific transcriptomic responses to changes in the nutritional environmentDryad Digital Repository, doi:10.5061/dryad.2q1301v.
- M Florencia Camus
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Laurent Keller, University of Lausanne, Switzerland
© 2019, Camus et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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