Mechanisms that maintain and remodel the sensory cilium

维持和重塑感觉纤毛的机制

• 批准号: 9889126
• 负责人: Niels Ringstad
• 金额: $ 25.43万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9889126
• 关键词: Acute; Afferent Neurons; Behavior; Binding; Biochemical; Biological Assay; Blindness; Caenorhabditis elegans; Carbon Dioxide; Cell physiology; Cell surface; Cells; Cellular Membrane; Chronic; Cilia; Cues; Cyclic GMP; Dendrites; Destinations; Development; Differentiation and Growth; Dioxygenases; Disease; Dynein ATPase; Enzymes; Esthesia; Fluorescence Microscopy; Functional disorder; Genes; Genetic; Genetic Screening; Genetic Transcription; Golgi Apparatus; Guanylate Cyclase; Homologous Gene; Hypoxia; Hypoxia Inducible Factor; In Situ; Integral Membrane Protein; Invertebrates; Left; Life; Light; Measurement; Measures; Mediating; Membrane; Metabolism; Microbe; Microtubules; Modeling; Molecular; Motor; Mutation; Nematoda; Neurons; Odors; Organelles; Pathway interactions; Photoreceptors; Physiological; Process; Proteins; Proteome; Reproduction; Resolution; Retinal Degeneration; Retinal Diseases; Retinal Dystrophy; Rhodopsin; Role; Second Messenger Systems; Sensory; Signal Transduction; Site; Stimulus; Stress; Structure; Surface; System; Testing; Transducers; Vertebrate Photoreceptors; Vesicle; atrial natriuretic factor receptor A; base; cell type; disease-causing mutation; experimental study; extracellular; hypoxia inducible factor 1; in vivo; novel; particle; photoreceptor degeneration; programs; protein transport; receptor; recruit; response; tool; trafficking; vesicle transport

PROJECT SUMMARY Sensory neurons concentrate and organize molecules used to detect environmental stimuli into cilia, which are specialized microtubule-based structures on the cell surface that function as cellular antennas. The proteins that constitute the machinery of sensory transduction are synthesized elsewhere and must be separated from other cellular proteins and transported to the cilium. The importance of mechanisms that mediate trafficking of proteins to the sensory cilium is illustrated by disease-causing mutations that disrupt this process. Mutations that compromise ciliary trafficking of the photopigment rhodopsin or the enzyme guanylyl cyclase cause retinal dystrophies marked by photoreceptor degeneration and, ultimately, blindness. Despite the importance of protein trafficking to the cilium, its underlying molecular mechanisms remain poorly understood. We propose to use chemosensory BAG neurons of the nematode C. elegans as a model for discovery of mechanisms that select and transport cargo destined for the sensory cilium. Like vertebrate photoreceptor neurons, BAG neurons use cyclic GMP as a second messenger for sensory transduction, and the enzymes and effectors that control cyclic GMP signals and turn them into electrical signals are highly similar to those found in photoreceptor neurons. Trafficking of proteins to BAG cilia can be measured in situ using high-resolution fluorescence microscopy assays, and powerful genetic tools are available to acutely or chronically manipulate specific molecular pathways in BAG neurons and determine their function in trafficking to the cilium. Importantly, C. elegans permits discovery of novel factors that mediate ciliary trafficking through genetic screens and biochemical approaches. We propose to use this powerful experimental system to (1) delineate a molecular pathway that matches cargo destined for the sensory cilium with specific motors that will carry it through the dendrite to its destination, and (2) determine how trafficking mechanisms are regulated by physiological or developmental cues that trigger remodeling of the BAG cilium. These studies will advance understanding of a cellular process that is essential for sensory neuron function and viability and will integrate cellular trafficking mechanisms with physiological and developmental programs that impact sensory cilia in vivo.

项目概要 感觉神经元将用于检测环境刺激的分子集中并组织到纤毛中，纤毛是 细胞表面上基于微管的特殊结构，充当蜂窝天线。蛋白质 构成感觉转导机制的物质在别处合成，必须与 其他细胞蛋白质并转运至纤毛。调解贩运人口的机制的重要性 蛋白质与感觉纤毛的关系可以通过破坏这一过程的致病突变来说明。突变 损害感光色素视紫红质或鸟苷酸环化酶的纤毛运输，导致视网膜 以光感受器退化为标志的营养不良，最终导致失明。尽管很重要 蛋白质向纤毛的运输，其潜在的分子机制仍然知之甚少。我们建议 使用线虫的化学感应 BAG 神经元作为模型来发现机制 选择并运输运往感觉纤毛的货物。像脊椎动物的感光神经元一样，BAG 神经元使用环鸟苷酸作为感觉转导的第二信使，并且使用酶和效应器 控制循环 GMP 信号并将其转化为电信号与在 感光神经元。可以使用高分辨率原位测量蛋白质向 BAG 纤毛的运输 荧光显微镜检测和强大的遗传工具可用于急性或慢性操纵 BAG 神经元中的特定分子途径并确定它们在运输到纤毛中的功能。 重要的是，秀丽隐杆线虫允许发现通过遗传介导纤毛运输的新因子。 筛选和生化方法。我们建议使用这个强大的实验系统来（1）描绘一个 将运往感觉纤毛的货物与携带该货物的特定马达相匹配的分子途径 通过树突到达目的地，以及（2）确定如何通过树突来调节贩运机制 触发 BAG 纤毛重塑的生理或发育线索。这些研究将推进 了解对于感觉神经元功能和活力至关重要的细胞过程，并将整合 细胞运输机制与影响感觉纤毛的生理和发育程序 体内。