The Role of Cryptochromes in Circadian Regulation of Metabolism

项目概要/摘要 昼夜节律在生物体中普遍存在，使它们能够预测和适应可预测的 24-小时昼夜循环。它们的功能是在时间上协调生理过程，例如 新陈代谢，在有机体中。因此，昼夜节律的破坏导致去兴奋化， 生物钟和复杂的代谢紊乱，如糖尿病。时钟控制的机制 下游代谢途径尚未完善。在这种关系中的核心角色之一是 核心时钟基因隐花色素（Cryptochrome，Cry）。CRY是维持节律和确定周期长度所必需的， 但它也与糖尿病和葡萄糖耐量有关。直到最近，人们还认为， 仅在细胞核中;我们最近的意外发现表明它也抑制细胞质中的异生 通过与Gsα的相互作用。与此同时，核CRY也调节胚胎异生，尽管是通过 完全不同的路径。总之，这种双管齐下的方法使CRY能够微调其对 葡萄糖稳态;然而，它在两个亚细胞区域的存在使得很难研究它的 具体的分室机制。为了克服这一挑战，我们创造了两种独特的试剂， 为每一个地区呐喊。将在原子和细胞水平上研究胞质CRY，以确定其结合 以及它们的相互作用如何决定它们的生化功能。核CRY将于 基因组规模，以揭示其与其他转录因子在增强子中的相互作用， 异源基因染色体构象捕获技术将使我们能够模拟整个细胞核 肝细胞特异性增强子结构。在治疗方面，我们将描述 从我们的筛选中鉴定出的新型时钟修饰化合物的作用。这些化合物具有 潜在的识别新的时钟基因和调节代谢，铺平了道路，走向临床翻译。 使用这些技术来研究CRY如何控制植物异生将是一个概念验证， 生物钟在调节组织特异性代谢途径中实现精确性。这些研究的成功将 显著提高对生物钟和生理或疾病之间串扰的理解 国家，以及提供了一个概念验证模型，应用基于细胞的研究结果，以改善人类健康。

Project Summary / Abstract Circadian rhythms are pervasive among organisms, allowing them to anticipate and adapt to the predictable 24-hour day-night cycle. Their function is to temporally coordinate physiological processes, such as metabolism, within the organism. Consequently, the disruption of circadian rhythms leads to desynchronized internal clocks and complex metabolic disorders, such as diabetes. The mechanism of how the clock controls downstream metabolic pathways is not well-established. One of the central players in this relationship is the core clock gene Cryptochrome (Cry). CRY is necessary to maintain rhythmicity and determine period length, but it has also been implicated in diabetes and glucose tolerance. Until recently, CRY was thought to function only in the nucleus; our recent unanticipated findings indicate it also inhibits gluconeogenesis in the cytoplasm through its interaction with Gsα. In parallel, nuclear CRY also regulates gluconeogenesis, albeit through a completely different pathway. Together, this two-pronged approach allows CRY to fine-tune its regulation of glucose homeostasis; however, its presence in two subcellular locales has made it difficult to study its compartment-specific mechanisms. To overcome this challenge, we created two unique reagents that localize CRY to each region. Cytosolic CRY will be studied at the atomic and cellular level to identify its binding partners and how their interactions determine their biochemical functions. Nuclear CRY will be investigated on the genomic scale to uncover its interactions with other transcription factors in the enhancers of gluconeogenesis genes. Chromosome conformation capture techniques will enable us to model nucleus-wide hepatocyte-specific enhancer architecture. On the therapeutic front, we will characterize the mechanism of action of novel clock-modifying chemical compounds identified from our screens. These compounds have the potential to identify novel clock genes and to regulate metabolism, paving the way towards clinical translation. The use of these techniques to study how CRY controls gluconeogenesis will be a proof-of-concept for how the clock achieves precision in modulating a tissue-specific metabolic pathway. The success of these studies will significantly improve the understanding of the crosstalk between the biological clock and physiology or disease states, as well as provide a proof-of-concept model for applying cell-based findings in improving human health.