Integrated Signaling and Transcriptional Networks in Circadian Clock Neurons

描述（由申请人提供）：这是一种系统生物学方法，涉及建模，以通过光输入调节哺乳动物昼夜节律钟的相位来解决重要的生物医学问题。生物钟是所有生物体的重要组成部分，对于维持生物体与环境的时间同步以及生物体内过程的节奏编排至关重要。生物钟功能的破坏导致睡眠/觉醒周期的破坏，并与心肺功能障碍和癌症、胃肠道疾病、抑郁症和改变有关。哺乳动物生物钟被带入光暗周期的分子机制是一个非常重要的问题。充分理解这一功能是非常重要的。待开发的方法解决了在理解光激活细胞内信号传导的机制中的基本未满足的需要，所述细胞内信号传导导致调节哺乳动物细胞中的细胞功能的转录结果。我们的目标是在自同步的视交叉上核（SCN）昼夜节律细胞中将光引发的信号传导与视网膜-下丘脑（RHT）光刺激反应中的基因表达联系起来。SCN是主时钟，协调整个身体的许多生物节律。反映环境和内部状态的输入被传输到SCN细胞受体，这些受体通过复杂的信号通路与时钟相互作用，最终使其控制节律性生理功能。通过RHT激活的光信号传导是进入生物钟功能的所有输入的最佳特征。已经发现对光信号的昼夜节律响应是昼夜节律相位相关的。在同步SCN细胞行为的背景下，这些影响的鲁棒性，结合来自文献的RHT信号的丰富的相关信息，为我们的目标提供了有利的环境。我们的实验策略使用析因设计方法结合药理学信号抑制进行全基因组表达谱分析。我们将整合基因表现资料与启动子资讯学，进行转录调控网路分析。这些结果将与现有文献整合，并用于推导信号通路。然后，我们将在不同的相互作用水平上通过实验验证模型结构。其结果将是一个实验验证的网络的光信号传导的基因表达的影响，在SCN介导的信号蛋白和最终转录因子之间的相互作用-使新的和直接验证的广泛研究领域的信号和基因表达之间的联系，这样做在生理相关的模型系统。

DESCRIPTION (provided by applicant): This is a systems biology approach involving modeling to approach the significant biomedical question of the mechanisms by light inputs adjust the phase of the mammalian circadian clock. The circadian clock is a critical component of all living organisms and is critical for the maintenance of temporal synchrony of the organism with the environment and rhythmic orchestration of processes within the organism. Disruption of circadian clock function results in disrupted sleep/wake cycles and has been associated with cardiorespiratory dysfunction and cancer, gastrointestinal disorders, depression and altered. The molecular mechanism by which mammalian circadian clocks are entrained to light-dark cycles is a highly significant problem. A full understanding of this function is significant. The approaches to be developed address a fundamental unmet need in understanding the mechanisms by which light activates intracellular signaling that leads to transcriptional consequences which modulate cellular function in mammalian cells. Our objective is to link light-initiated signaling to gene expression in the response of retino-hypothalamic (RHT) light stimulation in auto-synchronized suprachiasmatic nucleus (SCN) circadian cells. The SCN is the master clock, coordinating numerous biological rhythms throughout the body. Inputs reflecting environmental and internal status are transmitted to SCN cell receptors that interact with the clock through complex signaling pathways, ultimately allowing it to control rhythmic physiological functions. Light signaling through RHT activation is the best characterized of all inputs into the circadian clock function. The circadian response to light signaling has been found to be circadian phase-related. The robustness of these effects in the context of synchronous SCN cellular behavior, in conjunction with the wealth of relevant information on RHT signaling from the literature, provides an advantageous environment for our objective. Our experimental strategy uses a factorial design approach to genome-wide expression profiling combined with pharmacological signaling inhibition. We will employ transcriptional regulatory network analysis by integrating gene expression data with promoter informatics. These results will be integrated with existing literature and used to derive signaling pathways. We will then experimentally validate the model structure at the various levels of interaction. The result will be an experimentally verified network of the gene expression effects of light signaling in SCN mediated by interactions between signaling proteins and ultimately transcription factors - making novel and directly validated links between the extensively studied fields of signaling and gene expression, and doing so in a physiologically relevant model system.