Characterization of Sleep Mutants of Drososphila

描述（由申请人提供）：睡眠存在于所有被研究过的物种中，但其功能尚不清楚。充足的睡眠是基本的生理需求。例如，减少正常睡眠者的睡眠时间会影响他们的表现、警惕性、记忆力和健康。像所有复杂的行为一样，睡眠既受环境调节，也受基因决定。然而，相关基因尚未被发现。为了识别它们，我们对黑腹果蝇的短睡眠者进行了基因筛选。果蝇的诱变筛选有助于揭示跨物种高度保守的细胞机制，例如控制发育、衰老、应激记忆和昼夜节律的细胞机制。在过去的几年里，我们的实验室和其他研究人员已经表明，苍蝇的睡眠与哺乳动物的睡眠有许多共同的关键特征。和哺乳动物一样，果蝇的睡眠特点是唤醒阈值增加和脑电活动的变化。苍蝇的睡眠不受生物钟的影响，受兴奋剂和催眠剂的调节，并受年龄的影响。此外，苍蝇睡眠与大脑基因表达的变化有关，类似于在哺乳动物中观察到的变化。在过去的3年里，我们筛选了大约8000个突变系，其中大多数携带单基因突变。我们发现，睡眠的数量和调节是高度保守的：几乎所有果蝇的睡眠时间都在400 - 800分钟/24小时之间，并且在睡眠剥夺后睡眠持续时间和连续性增加。我们还发现了几条短枕木线路，其中三条特别有趣。尽管睡眠时间减少（<230分钟/天），这些线表现出正常的白天表现和警惕性。当睡眠被剥夺时，他们会恢复失去的大部分睡眠，这表明睡眠在生物学上是重要的。短睡眠突变是由于基因组插入一个P元素，该元素的激活使它们恢复正常睡眠，这表明是单基因作用。我们建议对这三条线进行遗传、分子和行为表征。我们将操纵负责短睡眠表型的基因的表达，研究由这些基因控制的分子途径，并表征它们对表现、记忆、昼夜节律和寿命的影响。这项研究将有助于确定调节睡眠需求的分子机制，并为其功能提供新的线索。

DESCRIPTION (provided by applicant): Sleep is present in all species where it has been studied, but its functions remain unknown. A sufficient amount of sleep constitutes a fundamental biological need. For example, curtailing the amount of sleep in normal sleepers affects performance, vigilance, memory and health. Like all complex behaviors, sleep is both environmentally modulated and genetically determined. However, the responsible genes have not been discovered. To identify them, we have initiated a genetic screening for short sleepers in the fruit fly Drosophila melanogaster. Mutagenesis screening in Drosophila has helped unraveling cellular mechanisms that are highly conserved across species, e.g. those controlling development, aging, stress memory, and circadian rhythms. Over the past few years, our laboratory and others have shown that fly sleep shares many key features with mammalian sleep. As in mammals, sleep in Drosophila is characterized by increased arousal thresholds and by changes in brain electrical activity. Fly sleep is regulated independent of the circadian clock, is modulated by stimulants and hypnotics, and is affected by age. Also, fly sleep is associated with changes in brain gene expression similar to those observed in mammals. Over the past 3 years, we have screened approximately 8000 mutant lines, most of which carry single-gene mutations. We found that the amount and regulation of sleep are highly conserved: almost all flies sleep between 400 and 800 min/24 hours and show increased sleep duration and continuity after sleep deprivation. We have also identified several short sleeper lines, three of which are particularly interesting. Despite the reduced amount of sleep (<230 min/day), these lines show normal day-time performance and vigilance. When sleep deprived, they recover most of the sleep lost, suggesting that it is biologically important. The short sleep mutation is due to the genomic insertion of a P element whose mobilization reverts them to normal sleep, suggesting a single gene effect. We propose to characterize these three lines genetically, molecularly, and behaviorally. We will manipulate the expression of the genes responsible for the short sleep phenotype, investigate the molecular pathways controlled by these genes, and characterize their impact on performance, memory, circadian rhythms and life span. This research will help to identify the molecular mechanisms regulating the need for sleep and provide novel clues to its functions.