Mechanisms of sensory hair cell reinnervation following lateral line cranial nerve damage in Danio rerio

斑马鱼侧线脑神经损伤后感觉毛细胞神经支配的机制

• 批准号: 10749736
• 负责人: Rohan Roy
• 金额: $ 5.27万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10749736
• 关键词: Acoustic Nerve; Affect; Auditory; Axon; Axotomy; Basement membrane; Brain; Brain-Derived Neurotrophic Factor; Cell membrane; Cell surface; Cells; Cochlea; Collagen; Confocal Microscopy; Cranial Nerves; Cues; Data; Development; Doctor of Philosophy; Epithelium; Extracellular Matrix; Fiber; Fishes; Fluorescence-Activated Cell Sorting; Ganglia; Genes; Genomics; Goals; Growth Cones; Hair Cells; Hearing; Human; Image; Imaging Techniques; Individual; Inner Hair Cells; Institution; Label; Labyrinth; Larva; Mammals; Mechanics; Memory; Mentorship; Microscopy; Modeling; Molecular; Natural regeneration; Nerve; Nerve Fibers; Nerve Regeneration; Nervous System; Neurites; Neurons; New York City; Olfactory Nerve; Organ; Organism; Pathology; Persons; Physical environment; Physiological; Population; Positioning Attribute; Publishing; Regenerative capacity; Regenerative research; Research Personnel; Resolution; Reverse Transcription; Role; Schwann Cells; Sensorineural Hearing Loss; Sensory; Sensory Hair; Signal Transduction; Structure; Synapses; System; Testing; Traction; Transgenes; Transgenic Organisms; United States; Universities; Zebrafish; afferent nerve; analog; axon growth; axon regeneration; axonal pathfinding; cell behavior; confocal imaging; deaf; deafness; experimental study; fluid flow; hearing impairment; hearing restoration; in vivo; insight; lateral line; mechanical signal; model organism; nerve damage; neuromast; neurotrophic factor; paracrine; prevent; programs; reinnervation; restoration; sensory mechanism; sound; supportive environment; transcriptome sequencing

PROJECT SUMMARY Loss of hearing is a prevalent sensory pathology in the United States that affects over 30 million people. A significant proportion of deafness is attributed to sensorineural hearing loss, which often involves the damage of afferent nerve fibers which relay auditory information from the mechanosensitive hair cells of the inner ear to the brain. The restoration of physiologic hearing would require the regeneration of afferent fibers into the sensory epithelium of the cochlea, followed by the reinnervation of appropriate hair cell targets. Nerve regeneration studies in humans and other mammalian models are lacking due to the limited accessibility of the inner ear. The zebrafish lateral line system, composed of superficial fluid-flow detecting hair cells and afferent nerve fibers, offers a simple and accessible model of nerve regeneration. In this model, there are likely various paracrine, juxtacrine, and neuron-autonomous signaling mechanisms working in coordination to guide axon pathfinding and target selection. Aim 1 of this proposal will determine the molecular cues expressed by target sensory hair cells to guide reinnervation by regenerating afferent axons of the lateral line. Following transection of the lateral line nerve, hair cells from the zebrafish will be isolated at multiple timepoints. In these hair cells, the expression changes of canonical and non-canonical molecular cues that may be used to attract axonal growth cones will be quantified through transcriptome sequencing. Aim 2 will investigate the neuronal bias for reinnervation of developmentally related hair cell populations. Although studies suggest that neurons retain a memory for their original hair cell targets, how this memory is established or maintained is unknown. A transgenic imaging technique will be used to label and trace clonal populations of regenerating axons following transection of the lateral line nerve. It is hypothesized that neurons prefer reinnervating hair cells that arose from a shared sensory placode during development. Aim 3 will reveal changes in the local physical environment of the regenerating nerve to allow entry of individual afferent fibers into their target organ. By imaging transgenic fish with fluorescently labeled Schwann cells and collagen, changes will be shown in Schwann cell tracts and the epithelial basement membrane to permit entry of individual axons into the zebrafish neuromast, which contains target hair cells. It is hypothesized that physical gaps form in Schwann cell and basement membrane layers in close proximity to denervated hair cells to allow passage of regenerating axons branching off the main nerve bundle. Together, these studies will elucidate the mechanisms governing afferent nerve regeneration and the reinnervation of hair cells, which may provide insight towards restoring hearing in the deafened human cochlea. These studies will be carried out under the direct mentorship of Dr. A. J. Hudspeth at The Rockefeller University and within the supportive environment of the Tri-Institutional MD-PhD Program in New York City.

项目摘要 在美国，听力丧失是一种普遍的感觉病理学，影响了3000万人。一个 耳聋的很大比例归因于感觉神经性听力损失，这通常涉及 传入的神经纤维将听觉信息从内耳的机械敏感毛细胞转移到 脑。恢复生理听力将需要将传入纤维再生到感官中 耳蜗的上皮，然后加重适当的毛细胞靶。神经再生 由于内耳的可及性有限，缺乏人类和其他哺乳动物模型的研究。这 斑马鱼侧线系统，由浅表流体流动检测毛细胞和传入神经纤维组成， 提供了一个简单易接收的神经再生模型。在此模型中，可能有各种旁分泌， 在协调方面起作用的近去二氨酸和神经元自主信号传导机制，以指导轴突探路和 目标选择。该提案的目标1将确定目标感觉表达的分子提示 毛细胞通过再生横向线的传入轴突来引导重新支配。在横断后 横向线神经，斑马鱼的毛细胞将在多个时间点分离。在这些毛细胞中， 可以用来吸引轴突生长的规范和非典型分子提示的表达变化 锥将通过转录组测序量化。 AIM 2将调查神经元偏差 加剧与发育相关的毛细胞群体。尽管研究表明神经元保留 对于原始的毛细胞目标的记忆，如何建立或维护此内存是未知的。一个 转基因成像技术将用于标记和追踪再生轴突的克隆种群 外侧线神经的横向。假设神经元更喜欢加强由此引起的毛细胞 在开发过程中共享的感官位置。 AIM 3将揭示当地物理环境的变化 再生神经，允许将个体传入纤维进入目标器官。通过成像 带有荧光标记的Schwann细胞和胶原蛋白的转基因鱼，将显示在Schwann细胞中 区域和上皮地下膜允许单个轴突进入斑马鱼神经瘤， 其中包含目标毛细胞。假设在Schwann细胞和地下室中形成了物理间隙 膜层紧密靠近隐居的毛细胞，以使再生轴突分支的通过 摆脱主神经束。这些研究将共同​​阐明控制传入神经的机制 再生和毛细胞的重新连接，这可能为恢复听力提供见识 聋哑的人耳蜗。这些研究将在A. J. Hudspeth博士的直接指导下进行 洛克菲勒大学以及在三机构MD-PHD计划的支持环境中 纽约市。