MPI of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, 01307 Dresden, Germany.
Biotechnologisches Zentrum, Technische Universität Dresden, Tatzberg 47/49, 01309 Dresden, Germany.
Biochim Biophys Acta Mol Cell Biol Lipids. 2020 Jul;1865(7):158683. doi: 10.1016/j.bbalip.2020.158683. Epub 2020 Mar 10.
During cold acclimation fruit flies switch their feeding from yeast to plant food, however there are no robust molecular markers to monitor this in the wild. Drosophila melanogaster is a sterol auxotroph and relies on dietary sterols to produce lipid membranes, lipoproteins and molting hormones. We employed shotgun lipidomics to quantify eight major food sterols in total lipid extracts of heads and genital tracts of adult male and female flies. We found that their sterol composition is dynamic and reflective of fly diet in an organ-specific manner. Season-dependent changes observed in the organs of wild-living flies suggested that the molar ratio between yeast (ergosterol, zymosterol) and plant (sitosterol, stigmasterol) sterols is a quantifiable, generic and unequivocal marker of their feeding behavior suitable for ecological and environmental population-based studies. The enrichment of phytosterols over yeast sterols in wild-living flies at low temperatures is consistent with switching from yeast to plant diet and corroborates the concomitantly increased unsaturation of their membrane lipids.
在冷驯化过程中，果蝇会将食物从酵母切换到植物性食物，但在野外没有可靠的分子标记物来监测这种情况。黑腹果蝇是固醇营养缺陷型，依赖于饮食中的固醇来产生脂膜、脂蛋白和蜕皮激素。我们采用 shotgun 脂质组学方法，定量分析了成年雌雄果蝇头部和生殖器总脂提取物中的八种主要食物固醇。我们发现，它们的固醇组成是动态的，并以器官特异性的方式反映了果蝇的饮食。在野外生活的果蝇器官中观察到的季节性变化表明，酵母（麦角固醇、酵母固醇）和植物（谷固醇、豆固醇）固醇之间的摩尔比是一种可量化的、通用的、明确的觅食行为标记物，适用于生态和环境的基于种群的研究。在低温下，野生果蝇中植物固醇相对于酵母固醇的富集与从酵母到植物性食物的转变一致，并证实了它们膜脂的不饱和度随之增加。
