Department of Human and Molecular Genetics, School of Medicine, Virginia Commonwealth University, Richmond, VA, 23298, USA.
Department of Molecular and Integrative Physiology and Geriatrics Center, University of Michigan, Ann Arbor, MI, 48109, USA.
Sci Rep. 2021 Oct 8;11(1):20044. doi: 10.1038/s41598-021-99483-7.
The Drosophila model is used to investigate the effects of diet on physiology as well as the effects of genetic pathways, neural systems and environment on feeding behavior. We previously showed that Blue 1 works well as a dye tracer to track consumption of agar-based media in Drosophila in a method called Con-Ex. Here, we describe Orange 4 as a novel dye for use in Con-Ex studies that expands the utility of this method. Con-Ex experiments using Orange 4 detect the predicted effects of starvation, mating status, strain, and sex on feeding behavior in flies. Orange 4 is consumed and excreted into vials linearly with time in Con-Ex experiments, the number of replicates required to detect differences between groups when using Orange 4 is comparable to that for Blue 1, and excretion of the dye reflects the volume of consumed dye. In food preference studies using Orange 4 and Blue 1 as a dye pair, flies decreased their intake of food laced with the aversive tastants caffeine and NaCl as determined using Con-Ex or a more recently described modification called EX-Q. Our results indicate that Orange 4 is suitable for Con-Ex experiments, has comparable utility to Blue 1 in Con-Ex studies, and can be paired with Blue 1 to assess food preference via both Con-Ex and EX-Q.
果蝇模型被用于研究饮食对生理的影响，以及遗传途径、神经系统和环境对摄食行为的影响。我们之前曾表明，Blue 1 可以很好地用作示踪染料，通过一种称为 Con-Ex 的方法追踪果蝇对琼脂基培养基的消耗。在这里，我们将 Orange 4 描述为一种用于 Con-Ex 研究的新型染料，它扩展了这种方法的用途。使用 Orange 4 进行的 Con-Ex 实验检测到饥饿、交配状态、品系和性别的预期影响对果蝇摄食行为的影响。在 Con-Ex 实验中，Orange 4 随时间线性地被消耗和排泄到小瓶中，使用 Orange 4 检测组间差异所需的重复次数与 Blue 1 相当，并且染料的排泄反映了消耗的染料量。在使用 Orange 4 和 Blue 1 作为染料对的食物偏好研究中，果蝇减少了对含有令人厌恶的味觉剂咖啡因和 NaCl 的食物的摄入，这是通过 Con-Ex 或最近描述的称为 EX-Q 的方法确定的。我们的结果表明，Orange 4 适合 Con-Ex 实验，在 Con-Ex 研究中与 Blue 1 具有相当的用途，并且可以与 Blue 1 配对，通过 Con-Ex 和 EX-Q 来评估食物偏好。
