The Effect of mWAKE in the Subfornical Organ on the Circadian Regulation of Water Consumption

项目摘要/摘要 昼夜节律对人类健康很重要。在分子水平上，它们是由一个自主的细胞控制的 分子时钟通常在不同的组织中同步。在哺乳动物中，这些局部时钟是 由视交叉上核(SCN)协调，后者是昼夜节律的起搏器。这一领域以前的大部分工作 集中在SCN如何调节神经元的生理和行为，以及局部时钟在 对这些过程的研究相对较少。特别是，大脑中额外的SCN振荡器的功能是 人们对此知之甚少。我们的实验室之前在果蝇体内发现了一种完全清醒的分子，它的作用是 以细胞自主的方式抑制神经元的活动，从而减少夜间的唤醒。 从苍蝇到哺乳动物，包括老鼠和人类，WAKE都是保守的。在老鼠身上，我们的实验室最近发现 小鼠的尾巴位于穹隆下器(SFO)。众所周知，这个大脑区域负责调节行为。 控制液体平衡和用水量。此外，SFO已被证明表现出强劲的循环 本地时钟振荡器，此外，用水量受到昼夜节律的控制。我的初步数据 建议mWAKE的减少会导致饮酒量的增加，特别是在夜间。加在一起， 这些发现让我假设，mWAKE通常会在夜间抑制促进口渴的SFO神经元。 由于SCN特有的机制也已被证明调节饮酒的昼夜节律方面，这个系统 可允许表征本地和中央时钟机制之间在调节 动机行为。在目标1中，我建议检查mWAKE在SFO中的表达是否具有节律性 并对SFO中mWAKE+细胞的性质进行了表征。在《目标2》中，我将调查 MWAKE对SFO神经元活性及mWAKE和mWAKE+细胞调节功能的影响 有节奏的用水量。这些研究应该为局部时钟如何帮助调节神经元提供新的见解 调节节律行为的活动。因为局部生物钟和SCN之间的去同步可能是 由轮班等常见活动产生，并可能与不良的健康结果有关，这些 有一天，研究可能会为未来的治疗提供与生物钟失调有关的信息。最后，提出了 实验将为我提供一个坚实的平台，以加强我的技术技能和概念背景 再加上我计划进行的职业和职业发展方面的培训，这将使我为未来做好准备 在生物医学研究中，成功地成为一名独立的调查者和不同学生的导师。

Project Summary/Abstract Circadian rhythms are important for human health. At a molecular level, they are controlled by a cell-autonomous molecular clock which is generally synchronized across different tissues. In mammals, these local clocks are coordinated by the suprachiasmatic nucleus (SCN), the circadian pacemaker. Most previous work in this field has focused on how the SCN regulates neuronal physiology and behavior, and the function of local clocks in these processes is relatively understudied. In particular, the functions of extra-SCN oscillators in the brain are poorly understood. Our lab previously identified a molecule Wide Awake (WAKE) in Drosophila, which acts downstream of the clock to reduce arousal at night by inhibiting neuronal activity in a cell-autonomous manner. WAKE is conserved from flies to mammals, including mice and humans. In mice, our lab has recently found that WAKE in mice is enriched in the subfornical organ (SFO). This brain region is known to regulate behaviors controlling fluid balance and water consumption. Moreover, the SFO has been shown to exhibit robust cycling of local clock oscillators, and furthermore water consumption is under circadian control. My preliminary data suggest that loss of mWAKE results in an increase in drinking, specifically during the night. Taken together, these findings lead me to hypothesize that mWAKE normally inhibits thirst-promoting SFO neurons at night. Because SCN-specific mechanisms have also been shown to regulate circadian aspects of drinking, this system may allow for characterization of the interplay between local and central clock mechanisms in regulating a motivated behavior. In Aim 1, I propose to examine whether mWAKE expression in the SFO is rhythmic and under clock control and to characterize the nature of mWAKE+ cells in the SFO. In Aim 2, I will investigate the effects of mWAKE on SFO neuronal activity and the function of mWAKE and mWAKE+ cells in regulating rhythmic water consumption. These studies should provide new insights into how local clocks help tune neuronal activity to modulate rhythmic behaviors. Because desynchrony between local body clocks and the SCN can be produced by common activities such as shift work and is likely associated with poor health outcomes, these studies may one day inform future therapies related to dysregulation of circadian clocks. Finally, the proposed experiments will provide a solid platform for me to strengthen my technical skills and conceptual background and, combined with my proposed training in career and professional development, will position me for future success as an independent investigator and a mentor for diverse students in biomedical research.