Research Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, UK
Research Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, UK.
Proc Biol Sci. 2017 Dec 20;284(1869). doi: 10.1098/rspb.2017.2237.
The sexes perform different reproductive roles and have evolved sometimes strikingly different phenotypes. One focal point of adaptive divergence occurs in the context of diet and metabolism, and males and females of a range of species have been shown to require different nutrients to maximize their fitness. Biochemical analyses in have confirmed that dimorphism in dietary requirements is associated with molecular sex differences in metabolite titres. In addition, they also showed significant within-sex genetic variation in the metabolome. To date however, it is unknown whether this metabolic variation translates into differences in reproductive fitness. The answer to this question is crucial to establish whether genetic variation is selectively neutral or indicative of constraints on sex-specific physiological adaptation and optimization. Here we assay genetic variation in consumption and metabolic fitness effects by screening male and female fitness of thirty genotypes across four protein-to-carbohydrate ratios. In addition to confirming sexual dimorphism in consumption and fitness, we find significant genetic variation in male and female dietary requirements. Importantly, these differences are not explained by feeding responses and probably reflect metabolic variation that, in turn, suggests the presence of genetic constraints on metabolic dimorphism.
性别在生殖方面扮演不同的角色，并且在进化过程中已经发展出有时非常不同的表型。适应分歧的一个焦点出现在饮食和代谢方面，许多物种的雄性和雌性都需要不同的营养物质来最大限度地提高它们的适应性。[期刊名称]中的生化分析证实，饮食需求的二态性与代谢物浓度的分子性别差异有关。此外，它们还显示出代谢组内显著的性别间遗传变异。然而，迄今为止，尚不清楚这种代谢变化是否会转化为生殖适应性的差异。这个问题的答案对于确定遗传变异是选择中性的，还是表明对特定性别生理适应和优化的限制至关重要。在这里，我们通过在四种蛋白质与碳水化合物比例下筛选 30 种基因型的雄性和雌性适应性来检测消耗和代谢适应性的遗传变异。除了证实消耗和适应性方面的性别二态性外，我们还发现了雄性和雌性饮食需求方面的显著遗传变异。重要的是，这些差异不能用摄食反应来解释，可能反映了代谢变异，这反过来表明代谢二态性存在遗传限制。
