Sex-specific plasticity and the nutritional geometry of insulin-signaling gene expression in Drosophila melanogaster

Background

Sexual-size dimorphism (SSD) is replete among animals, but while the selective pressures that drive the evolution of SSD have been well studied, the developmental mechanisms upon which these pressures act are poorly understood. Ours and others’ research has shown that SSD in D. melanogaster reflects elevated levels of nutritional plasticity in females versus males, such that SSD increases with dietary intake and body size, a phenomenon called sex-specific plasticity (SSP). Additional data indicate that while body size in both sexes responds to variation in protein level, only female body size is sensitive to variation in carbohydrate level. Here, we explore whether these difference in sensitivity at the morphological level are reflected by differences in how the insulin/IGF-signaling (IIS) and TOR-signaling pathways respond to changes in carbohydrates and proteins in females versus males, using a nutritional geometry approach.

Results

The IIS-regulated transcripts of...

背景
性体型二态性（Sexual-size dimorphism, SSD）广泛存在于动物界。尽管驱动性体型二态性演化的选择压力已得到充分研究，但这些压力作用的发育机制仍不明晰。本团队及其他学者的研究表明，黑腹果蝇（D. melanogaster）的性体型二态性体现出雌性相较于雄性拥有更高水平的营养可塑性：即性体型二态性随膳食摄入量与体型的增加而增强，该现象被命名为性别特异性可塑性（sex-specific plasticity, SSP）。另有研究数据表明，尽管两性体型均会随蛋白质水平的波动发生改变，但仅雌性体型对碳水化合物水平的变化具有敏感性。本研究采用营养几何学研究方法，探究雌雄个体在胰岛素/胰岛素样生长因子信号通路（insulin/IGF-signaling, IIS）与TOR信号通路对碳水化合物、蛋白质变化的响应差异，是否能够反映上述形态层面的敏感性差异。
研究结果
胰岛素/胰岛素样生长因子信号通路调控的转录本...