Analysis of clock proteins in their non-circadian roles

生物钟是进化保守的行为和生理的协调者 流程。人类生物钟的故障会导致严重的疾病，如睡眠 疾病和癌症。生物钟的计时是由分子反馈环完成的，分子反馈环 涉及几个时钟基因及其蛋白质。周期(PER)和永恒(TIM)两个基因的作用 已经在时钟反馈回路中得到了很好的建立，时钟反馈回路在模式生物中运行 黑腹果蝇。这两个基因的产物，蛋白质PER和TIM，转位到 细胞核并随后降解；这两个事件对于时钟功能是必不可少的。 令人惊讶的是，在卵巢中，这些蛋白质的表现不同。它们的水平不会循环；相反，它们 在任何时候都保持稳定和细胞质。我们有证据表明非昼夜节律的表达 卵巢中的PER和TIM可能在产卵调节中起重要作用。我们 假设时钟基因可能与信号通路的组成部分相互作用 管理代谢动态平衡和营养分配。我们建议使用生化和遗传技术 在两个具体目标上检验这一假设的工具。首先，我们将学习遗传和生化 卵巢中PER和TIM的相互作用及生殖力测定 相关表型。第二，我们将进行蛋白质相互作用筛选，以确定新的蛋白质 可能与细胞质中的PER和TIM相互作用。这项研究的结果将给我们 对时钟蛋白非昼夜节律表达的功能意义的重要见解。 越来越多的证据表明，被认为只起时钟成分作用的基因 还有其他重要的多效性作用。在苍蝇和哺乳动物中，它们的行为都是非昼夜节律的。 因此，理解模式生物体中时钟基因的非昼夜节律功能应该 为与人类健康相关的类似过程提供有价值的见解。

Circadian clocks are evolutionary conserved coordinators of behavioral and physiological processes. Malfunctions of circadian clocks in humans lead to serious pathologies such as sleep disorders and cancer. Circadian timekeeping is accomplished by molecular feedback loops that involve several clock genes and their proteins. The role of two genes period(per)and timeless(tim) has been well established in the clock feedback loop, which operates in the model organism Drosophila melanogaster. The products of these two genes, proteins PER and TIM,translocate to cell nuclei and are subsequently degraded; both events are essential for clock function. Surprisingly, in the ovary, these proteins behave differently. Their levels do not cycle; instead, they remain stable and cytoplasmic at all times. We have evidence that non-circadian expression of PER and TIM in the ovary may have important functions in the modulation of egg production. We hypothesize that clock genes may be interacting with components of signaling pathways that govern metabolic homeostasis and nutrient allocation. We propose to use biochemical and genetic tools to test this hypothesis in two specific aims. First, we will study genetic and biochemical interactions of PER and TIM in the ovary and test their functional significance using fecundity related phenotypes. Second, we will perform protein interaction screens to identify novel proteins that may interact with cytoplasmic PER and TIM. Results obtained in this study will give us important insights into the functional significance of non-circadian expression of clock proteins. There is increasing evidence that genes that were thought to act exclusively as clock components have other important pleiotropic roles. They act in a non-circadian manner in both fly and mammals. Therefore, understanding the non-circadian functions of clock genes in a model organism should provide valuable insights into similar processes related to human health.