Characterization of the sleep-regulation role of the Rab GTPase, lightoid

描述（由申请人提供）：睡眠是一种高度保守的行为，是迄今为止研究的所有动物的适当健康和认知所必需的，但尚未描述睡眠的功能。黑腹果蝇表现出许多哺乳动物睡眠的特征，包括唤醒阈值增加，固定不动，以及昼夜节律和稳态驱动的调节。虽然近年来在了解调节果蝇昼夜节律的神经回路和分子通路方面取得了很大进展，但对稳态驱动对睡眠的调节知之甚少。在最近的一次筛选涉及调节睡眠行为的基因的研究中，我们发现，缺乏功能性Rab GT3基因拷贝的果蝇，比背景对照至少每24小时少睡200分钟。此外，其他人的工作表明：（1）ltd的表达是时钟依赖性的，（2）ltd的表达是睡眠/觉醒调节的，（3）ltd是适当的长期记忆所必需的，（4）ltd是人类基因Rab 32的同源物，Rab 32的功能是定位PKA，一种已知的睡眠调节剂。本研究的目的是通过以下三种方法来更好地了解ltd调节睡眠行为的机制：（1）我将分析4个ltd等位基因对睡眠行为的几个方面的影响，包括总睡眠时间，睡眠时间，睡眠次数，睡眠潜伏期，剥夺后的睡眠反弹和总寿命。(2)我将使用定量PCR方法分析ltd的调节，以确定ltd是否受昼夜节律驱动、稳态睡眠驱动或光线的调节。(3)为了确定哪些大脑区域足以发挥其睡眠调节作用，我将使用几种GAL 4驱动程序进行组织特异性拯救实验，这些驱动程序驱动大脑已知睡眠调节区域的表达。这里提出的工作将提供一个更好的了解新的睡眠基因，有限责任公司，如何调节睡眠。此外，基于其与分子钟，学习和记忆以及PKA的联系，对ltd的拟议研究可以提供睡眠生物学这些不同方面之间的分子联系。最后，这项工作将确定ltd作为一个很好的候选人，以帮助诊断睡眠障碍，如失眠症和嗜睡症，以及一个潜在的药物靶点，提供治疗。我们对睡眠的功能和调节感兴趣。目前，我们使用果蝇，一种最近被证明是睡眠行为的优秀模型的动物，来帮助理解神经回路如何控制睡眠/觉醒行为，以及识别可用于识别和治疗人类睡眠障碍的新基因。

DESCRIPTION (provided by applicant): Sleep is a highly conserved behavior that is required for proper health and cognition in all animals studied to date, yet a function for sleep has not been described. Drosophila melanogaster exhibits many of the hallmarks of mammalian sleep, including increased arousal threshold, consolidated immobility, and regulation by both circadian rhythm and a homeostatic drive. Although great strides have been made in recent years towards understanding the neural circuitry and molecular pathways that regulate circadian rhythm in Drosophila, the regulation of sleep by the homeostatic drive is poorly understood. In a recent screen for genes involved in regulating sleep behavior, we found that flies lacking a functional copy of the Rab GTPase, lightoid (ltd), sleep at least 200min per 24h less than background controls. In addition, work by others has suggested that (1) the expression of ltd is Clock-dependent, (2) the expression of ltd is sleep/wake-regulated, (3) ltd is required for proper long-term memory, and (4) ltd is a homologue of the human gene, Rab32, which functions to localize PKA, a known regulator of sleep. The goal of the proposed project is to better understand the mechanism by which ltd regulates sleep behavior by taking 3 approaches: (1) I will analyze 4 ltd alleles for several aspects of sleep behavior, including overall sleep duration, sleep bout length, number of sleep bouts, latency to sleep, sleep rebound after deprivation, and total life span. (2) I will analyze the regulation of ltd using a quantitative PCR approach to determine if ltd is regulated by circadian drive, the homeostatic sleep drive, or light. (3) To determine in which brain regions ltd is sufficient to perform its sleep-regulation role, I will perform a tissue-specific rescue experiment with several GAL4 drivers that drive expression in known sleep-regulating areas of brain. The work proposed here will provide a better understanding of how the new sleep gene, ltd, regulates sleep. Furthermore, based on its connections to the molecular clock, learning & memory, and PKA, the proposed investigation of ltd could provide a molecular link between these disparate aspects of sleep biology. Finally, this work will identify ltd as an excellent candidate to aid in the diagnosis of sleep disorders such as insomina and somnabalism, as well as a potential drug target to offer treatment. We are interested in the function and regulation of sleep. Currently, we use the fruitfly, an animal that has recently been shown to be an excellent model for sleep behavior, to help understand how neural circuits control sleep/wake behavior, as well as to identify new genes that could be used to identify and treat sleep disorders in humans.