Identifying the role of the ocular immune response in age-related sleep disturbances

项目摘要 睡眠是进化过程中的一种保守功能，对维持健康和促进长寿至关重要。 随着年龄的增长，睡眠质量下降，通常先于疾病发作，并与疾病发作相关。 然而，睡眠衰老的机制尚不清楚。在人类和果蝇中， 果蝇，内源性生物钟，设置24小时的睡眠和活动节奏， 受到从眼睛接收的光输入的影响。然而，随着年龄的增长，视力会下降， 抑制昼夜节律。伴随着这种下降，是免疫系统的慢性激活。一 免疫应答的中心调节因子是转录因子核因子κ-B（NF-κB），其在 苍蝇和哺乳动物都协调对细菌病原体和损害信号的反应。使用 利用生物信息学方法，我们在果蝇中发现，NF-κB调控的基因表达升高， 感光细胞中的蛋白质。考虑到这一观察结果，我们测试了假设， 发生在眼睛随着年龄的增长而驱动睡眠衰老。我们发现，抑制NF-κB B同源物， 感光细胞维持总睡眠时间和睡眠巩固随着年龄的增长，这表明， 眼部免疫反应驱动睡眠衰老。此外，我们发现， 持续黑暗抑制了果蝇头部NF-κ B调控基因的表达，表明NF-κB 活动由光调节。这项建议以这些初步调查结果为基础，有两个具体目标。在目标1中， 我们将鉴定出眼睛中受NF-κB调节的基因，这些基因驱动睡眠衰老。完成 为此，我们编制了一份基因清单，这些基因的表达在光感受器中发生了显着变化， 老了，老了。我们将抑制光感受器中的每一个候选基因， 这些基因的功能丧失睡眠表型模仿了调味品的效果。在目标#2中，我们将坚定地建立 光和光转导信号级联是否促进光感受器中的NF-κB活性。为 为此，我们将使用现有的基于内切酶的NF-κB基因报告基因， 感光细胞利用果蝇强大的遗传工具，我们将能够测试 参与光转导信号级联的基因影响NF-κB荧光素酶报告基因活性， 以确定光调节NF-κB的机制。最终，这项工作将揭示 通过眼睛衰老影响睡眠衰老，并将确定保守的遗传目标， 在哺乳动物中调节以随年龄保持睡眠质量。

Project Summary Sleep is a conserved function across evolution that is critical for maintaining health and promoting longevity. With age, there are declines in sleep quality that often precede, and are associated with, the onset of disease. However, the mechanisms responsible for sleep senescence are unclear. In both humans and the fruit fly, Drosophila melanogaster, endogenous circadian clocks that set 24h rhythms in sleep and activity are influenced by light input received from the eye. However, with age, there are declines in vision and a dampening of circadian rhythms. Concomitant with this decline, is a chronic activation of the immune system. A central regulator of the immune response is the transcription factor Nuclear Factor Kappa-B (NF-κB), which in both flies and mammals coordinates the response to bacterial pathogens and damage signals. Using a bioinformatics approach in Drosophila, we identified that genes regulated by NF-κB show elevated expression in the photoreceptor cells with age. With this observation in mind, we tested the hypothesis that changes that occur in the eye with age drive sleep senescence. We found that inhibiting the NF-κB homolog, relish, in the photoreceptor cells maintains total sleep time and sleep consolidation with age, suggesting that increases in the ocular immune response drives sleep senescence. Furthermore, we have identified that housing flies in constant darkness suppresses the expression of NF-κB-regulated genes in the fly head, indicating that NF-κB activity is regulated by light. This proposal builds on these preliminary findings with two specific aims. In Aim#1, we will identify genes that are regulated by NF-κB in the eye and that drive sleep senescence. To accomplish this, we have compiled a list of genes whose expression is significantly changed in the photoreceptors with age, and with loss of relish. We will inhibit each of these candidate genes in the photoreceptors and identify genes whose loss-of-function sleep phenotype mimics the effect of relish. In Aim #2, we will firmly establish whether light and the phototransduction signaling cascade promotes NF-κB activity in the photoreceptors. For this, we will use an existing luciferase-based genetic reporter for NF-κB that we can express in the photoreceptor cells. Using the powerful genetic tools available to Drosophila, we will be able to test whether genes involved in the phototransduction signaling cascade affect NF-κB luciferase reporter activity, allowing us to pinpoint the mechanism through which light regulates NF-κB. Ultimately, this work will reveal the mechanism through which eye aging affects sleep senescence, and will identify conserved genetic targets that may be modulated in mammals for preserving sleep quality with age.