Regulation of taste neuron morphology and function

项目摘要： 味觉传导细胞检测我们食物中的化学物质，并将此信息传达给外周味觉 神经节神经元（味觉神经元），将这些信息传递到大脑。味觉神经元的轴突在 分枝特征，有的分枝少，有的分枝多。然而，目前还不清楚如何 这些不同的形态是可塑性和/或功能的基础。我们的目标是澄清 味觉神经元的形态、可塑性、遗传类型和功能，以便深入了解外周 味觉系统的组织。味觉神经元形态可能是连接差异的基础，但也是 可能是由可塑性调节的。即使在成年人中，味觉感受器细胞也会不断更新， 吸引并连接到神经纤维，并且神经元形态的一些变化可能作为该过程的一部分而发生。 此外，神经元分支之间的差异可能具有功能重要性。比如说， 简单分支的神经元只能与少数味觉传导细胞连接，而严重分支的神经元只能与少数味觉传导细胞连接， 可能连接到更多的味觉传导细胞。目前，这些差异的重要性， 趋同性不明确。在这个项目中，我们建议调查调节味觉差异的因素 神经元形态和神经元之间的分支特征，并将这些因素与神经元功能相关联。 具体来说，在目标1中，我们将确定味觉神经元轴突形态的哪些方面是稳定的， 随着时间的推移而改变。在目标2中，我们将确定神经元形态的哪些方面是由 内在因素（即，细胞类型）以及该因子与功能的关系。最后，在目标3中，我们将确定 神经元形态的哪些方面由外在（即，神经营养因子 以及这些特征与神经元功能的关系。我们假设味蕾内部的分支是受 而味蕾外的分支是由内在和外在的组合来调节的。 特征，影响味觉神经元的敏感性和调谐宽度。

Project Summary: Taste-transducing cells detect chemicals in our food and communicate this information to peripheral taste ganglion neurons (taste neurons), which carry this information to the brain. The axons of taste neurons vary in branching characteristics, some branching little and others branching a great deal. However, it is unclear how these differing morphologies underly plasticity and/or function. Our goal here is to clarify the relationship between taste neuron morphology, plasticity, genetic type, and function in order to gain insight into the peripheral organization of the taste system. Taste neuron morphology may underlie differences in connectivity, but is also likely regulated by plasticity. Even in adults, taste receptor cells undergo continuous renewal and must constantly attract and connect to nerve fibers, and some variation in neuron morphology likely occurs as part of this process. Additionally, differences between neurons in their branching likely have functional importance. For example, simply branched neurons can only connect with a few taste-transducing cells, while heavily branched neurons likely connect to many more taste-transducing cells. Currently, the significance of these differences in convergence are unclear. In this project, we propose to investigate factors that regulate differences in taste neuron morphology and branching characteristics between neurons and relate these factors to neuron function. Specifically, in Aim 1, we will determine which aspects of the axon morphologies of taste neurons are stable and which change over time. In Aim 2, we will determine which aspects of neuron morphologies are determined by an intrinsic factor (i.e., cell type) and how this factor correlates with function. Finally, in Aim 3, we will determine which aspects of neuron morphologies are determined by extrinsic (i.e., neurotrophins) developmental factors and how these features relate to neuron function. We hypothesize that branching inside the taste bud is regulated by plasticity, while branching outside the taste bud is regulated by a combination of intrinsic and extrinsic features, which influence taste neuron sensitivity and breadth of tuning.