Zhang Yali V, Aikin Timothy J, Li Zhengzheng, Montell Craig
Neuroscience Research Institute and Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
Neuroscience Research Institute and Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
Neuron. 2016 Aug 17;91(4):863-877. doi: 10.1016/j.neuron.2016.07.013. Epub 2016 Jul 28.
Food texture has enormous effects on food preferences. However, the mechanosensory cells and key molecules responsible for sensing the physical properties of food are unknown. Here, we show that akin to mammals, the fruit fly, Drosophila melanogaster, prefers food with a specific hardness or viscosity. This food texture discrimination depends upon a previously unknown multidendritic (md-L) neuron, which extends elaborate dendritic arbors innervating the bases of taste hairs. The md-L neurons exhibit directional selectivity in response to mechanical stimuli. Moreover, these neurons orchestrate different feeding behaviors depending on the magnitude of the stimulus. We demonstrate that the single Drosophila transmembrane channel-like (TMC) protein is expressed in md-L neurons, where it is required for sensing two key textural features of food-hardness and viscosity. We propose that md-L neurons are long sought after mechanoreceptor cells through which food mechanics are perceived and encoded by a taste organ, and that this sensation depends on TMC. VIDEO ABSTRACT.
食物质地对食物偏好有着巨大影响。然而，负责感知食物物理特性的机械感觉细胞和关键分子尚不清楚。在这里，我们表明，与哺乳动物类似，果蝇（黑腹果蝇）更喜欢具有特定硬度或粘度的食物。这种食物质地辨别取决于一种先前未知的多树突（md-L）神经元，它延伸出精细的树突分支，支配着味觉毛的基部。md-L神经元对机械刺激表现出方向选择性。此外，这些神经元根据刺激的强度协调不同的进食行为。我们证明，果蝇单一的跨膜通道样（TMC）蛋白在md-L神经元中表达，在那里它是感知食物硬度和粘度这两个关键质地特征所必需的。我们提出，md-L神经元是长期以来一直寻找的机械感受器细胞，通过它食物的力学特性被味觉器官感知和编码，并且这种感觉依赖于TMC。视频摘要。
