Regulation of sleep-like behavior in C. elegans

描述（由申请人提供）：本研究的长期目标是了解睡眠和类睡眠状态的基因调控。睡眠-觉醒调节包括时钟定时和睡眠开始和偏移信号。睡眠状态的执行需要感觉门控，这是指睡眠期间反应性降低的现象。感觉门控是一种鲜为人知的睡眠基本特性，它将睡眠与安静的清醒状态区分开来。本研究旨在利用秀丽隐杆线虫的模式生物，促进我们对感觉门控机制的理解。该方法是研究在线虫生命周期中发生的嗜睡期。在本研究期间，需要验证的整体假设是EGL-4/PKG和cAMP信号在感觉神经元中拮抗作用，以调节昏睡期间的感觉输入，而减少的感觉输入反过来促进了类睡眠行为。这一全球性假设将通过四个具体目标得到检验。特异性目的1将检验嗜睡期间调节感觉反应的分子机制与调节化学感觉适应的分子机制相同的假设。这一假设将通过评估在昏睡期间感觉适应缺陷和感觉门控缺陷之间的关联来检验。此外，我们将测试动物在昏睡期间是否比昏睡之外更容易适应。特异性目的2将验证cAMP信号在感觉神经元中拮抗昏睡时感觉门控的假设。这一假设将通过表达pde-4基因来验证，pde-4通常会在感觉神经元中降解cAMP。此外，我们将评估egl-4和pde-4之间的基因顺序关系，以调节感觉门控。具体目标3将检验感觉输入调节类睡眠行为的假设。第三个目标将通过检查在昏睡期间抑制感觉输入以及减少感觉功能的突变和操作对睡眠样行为的影响来检验。最后的具体目标是进行基因筛选，以确定在功能突变体的egl-4增益中增强睡眠样行为所需的基因。考虑到睡眠和类睡眠状态的系统发育守恒，以及cgmp和camp依赖性信号通路的守恒，这些实验很可能会为其他物种的睡眠调节提供线索。提高对睡眠调节的理解将加强对睡眠障碍患者的诊断和治疗。公共卫生相关性：睡眠障碍和睡眠剥夺是尚未解决的主要公共卫生问题。本建议旨在增加我们对睡眠调节的理解，以加强对睡眠障碍患者的诊断和治疗。

DESCRIPTION (provided by applicant): The long-term goal of this research is to understand the genetic regulation of sleep and sleep-like states. Sleep-wake regulation consists of clock timing and of sleep onset and offset signals. Execution of the sleep state requires sensory gating, which refers to the phenomenon of reduced responsiveness during sleep. Sensory gating is a poorly-understood yet fundamental property of sleep that distinguishes it from quiet wakefulness. This proposal aims to advance our mechanistic understanding of sensory gating using the model organism Caenorhabditis elegans. The approach is to study lethargus, a sleep-like period that occurs during the life cycle of C. elegans. In this grant period, the global hypothesis to be tested is that EGL-4/PKG and cAMP signaling act antagonistically in sensory neurons to regulate sensory input during lethargus, and that reduced sensory input in turn facilitates sleep-like behavior. This global hypothesis will be tested through four specific aims. Specific aim 1 will test the hypothesis that the molecular mechanism that regulates sensory responsiveness during lethargus is the same molecular mechanism that regulates chemosensory adaptation. This hypothesis will be tested by assessing for an association between defects in sensory adaptation and defects in sensory gating during lethargus. Additionally, we will test whether animals adapt more readily during lethargus than outside of lethargus. Specific aim 2 will test the hypothesis that cAMP signaling acts in sensory neurons to antagonize sensory gating during lethargus. This hypothesis will be tested by expressing the gene pde-4, which normally degrades cAMP, in sensory neurons. In addition, we will assess the gene order relationship between egl-4 and pde-4 is regulating sensory gating. Specific aim 3 will test the hypothesis that sensory input regulates sleep-like behavior. This third aim will be tested by examining the effects on sleep-like behavior of dampening sensory input during lethargus and of mutants and operations that reduce sensory function. The final specific aim will perform a genetic screen to identify genes required for the enhanced sleep- like behavior in egl-4 gain of function mutants. Given the phylogenetic conservation of sleep and sleep-like states and the conservation of cGMP-and cAMP-dependent signaling pathways, it is likely that these experiments will shed light on sleep regulation in other species. Improved understanding of sleep regulation will enhance the diagnosis and treatment of people with sleep-disorders. PUBLIC HEALTH RELEVANCE: Sleep disorders and sleep deprivation are major unmet public health problems. This proposal aims to add to our understanding of sleep regulation, in order to enhance the diagnosis and treatment of patients with sleep disorders.