Mechanisms of slowpoke in regulating circadian behavior

描述（由申请人提供）：许多生物现象遵循每日循环时间的过程。昼夜节律紊乱与睡眠障碍、癌症和神经紊乱有关。此外，生物钟还控制着许多疾病过程和对药物的生理反应。为了更好地了解生物钟，我们进行了全基因组分析，以确定果蝇和小鼠的生物钟控制基因。我们发现，果蝇和它的脊椎同系物Kcnmal是两个物种中为数不多的受生物钟控制的基因之一。果蝇体内的慢速基因突变导致运动活动节律异常。这表明slo/Kcnmal在调节昼夜节律行为中起着重要作用。本建议的具体目的是首先通过免疫组织化学和原位杂交来表征慢表达细胞。使用GAL4-UAS系统，我们将测试这些细胞对节律性运动活动的需求。其次，通过分子、遗传和行为分析，我们将研究慢节奏在昼夜节律系统遗传层次中的位置。我们的研究还将扩展到Kcnmal在小鼠起搏器神经元中的节律性表达的生理功能。我们将测量Kcnmal sirna对起搏器细胞放电节律的影响。总之，了解slow和Kcnmal的功能是将分子“时钟”与生理和行为输出联系起来的关键一步。鉴于昼夜节律调节途径的普遍存在，以及昼夜节律周期对生物体整体健康和人类健康的重要性，本研究最终将有助于解剖人体时钟和生物钟调节活动。

DESCRIPTION (provided by applicant): Numerous biological phenomena follow a daily cycling time course. Disturbances of circadian rhythms are linked to sleep disorders, cancer and neurological disorders. In addition, the circadian clock also controls many disease processes and physiological responses to medications. To better understand circadian clocks, we have carried out genome-wide analysis to identify clock-controlled genes in Drosophila and mouse. We found Drosophila slowpoke (slo) or its vertebrate homolog, Kcnmal, to be one of the few genes that is controlled by the clock in both species. A mutation of slo in flies results in aberrant rhythms in locomotor activity. This suggests that slo/Kcnmal plays an important role in regulating circadian behavior. The specific aims of this proposal are to first characterize slo-expressing cells by immunohistochemistry and in situ hybridization. Using the GAL4-UAS system, we will test the requirement of these cells for rhythmic locomotor activity. Second, through molecular, genetic and behavioral analyses, we will investigate the placement of slo in the genetic hierarchy of the circadian system. Our study will also extend to the physiological function of rhythmically expressed Kcnmal in the mouse pacemaker neurons. We will measure the effect of Kcnmal siRNAs on the firing rhythm of pacemaker cells. Together, understanding the functions of slo and Kcnmal is a key step linking the molecular "clock" to physiological and behavioral outputs. Given the ubiquity of circadian-regulated pathways and the importance of circadian cycles to the overall fitness of organisms and to human health, this study will ultimately assist the dissection of the human clock and clock-regulated activity.