Cul3 and the BTB adaptor insomniac are key regulators of sleep homeostasis and a dopamine arousal pathway in Drosophila.
Cul3 and the BTB adaptor insomniac are key regulators of sleep homeostasis and a dopamine arousal pathway in Drosophila.
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DOI：
10.1371/journal.pgen.1003003
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发表时间：
2012
期刊：
影响因子：
4.5
通讯作者：
Allada R
中科院分区：
文献类型：
--
作者：
Pfeiffenberger C;Allada R
睡眠是自平衡调节的，因此睡眠驱动力反映了先前清醒的持续时间。然而，尽管发现了对睡眠很重要的基因，但一个连贯的睡眠稳态分子模型还没有出现。为了更好地了解睡眠的功能和调节，我们在果蝇身上采用了反向遗传学的方法。插入BTB结构域蛋白CG32810/失眠(INC)显示了迄今为止观察到的最强的基线睡眠表型之一，∼10小时睡眠减少。重要的是，这与对睡眠剥夺的稳态反应减少有关，这与睡眠稳态被扰乱是一致的。敲除与INC相互作用的蛋白E3泛素连接酶CUL3会导致睡眠时间减少、巩固和内环境稳定，这表明蛋白质周转在介导INC效应中起着重要作用。有趣的是，Inc和CUL3在有丝分裂后神经元发育过程中的表达有助于它们的成年睡眠功能。与多巴胺能信号增加的果蝇类似，Inc和CUL3的缺失会导致成年果蝇对机械刺激的高唤醒能力。此外，INC睡眠持续时间表型可以通过药物抑制酪氨酸羟基酶来挽救，酪氨酸羟化酶是多巴胺生物合成的限速酶。综上所述，这些结果确立了Inc.和CUL3在设定果蝇睡眠稳态和多巴胺能兴奋途径方面的重要新角色。睡眠是一种基本的行为，大约占我们生活的三分之一；然而，其潜在的功能仍然是一个谜。果蝇已经成为理解睡眠行为的重要模型系统，表现出与哺乳动物睡眠的几个行为和遗传相似之处，包括巩固的不动、对一系列刺激的唤醒阈值的提高、内环境平衡驱动以及被证实的兴奋剂和镇静剂的操纵。我们测试了候选睡眠基因的中断，并确定了一种名为失眠症的基因，它表现出迄今为止最强大和最健壮的睡眠表型之一，包括对睡眠剥夺的自稳反应受到抑制。我们发现了一个与INC和已知的蛋白质降解调节因子CUL3相互作用的基因的相似表型，CUL3将睡眠稳态与蛋白质周转联系起来。重要的是，我们发现失眠症在大脑中一个已知的唤醒系统中发挥作用，正如神经递质多巴胺所定义的那样。这项工作发现了一种新的多巴胺能唤醒途径的分子成分，为睡眠稳态的遗传基础提供了重要的见解。考虑到苍蝇和哺乳动物系统的保守性，这些研究可能会导致对调节人类睡眠稳态和唤醒的分子有新的见解。
Sleep is homeostatically regulated, such that sleep drive reflects the duration of prior wakefulness. However, despite the discovery of genes important for sleep, a coherent molecular model for sleep homeostasis has yet to emerge. To better understand the function and regulation of sleep, we employed a reverse-genetics approach in Drosophila. An insertion in the BTB domain protein CG32810/insomniac (inc) exhibited one of the strongest baseline sleep phenotypes thus far observed, a ∼10 h sleep reduction. Importantly, this is coupled to a reduced homeostatic response to sleep deprivation, consistent with a disrupted sleep homeostat. Knockdown of the INC-interacting protein, the E3 ubiquitin ligase Cul3, results in reduced sleep duration, consolidation, and homeostasis, suggesting an important role for protein turnover in mediating INC effects. Interestingly, inc and Cul3 expression in post-mitotic neurons during development contributes to their adult sleep functions. Similar to flies with increased dopaminergic signaling, loss of inc and Cul3 result in hyper-arousability to a mechanical stimulus in adult flies. Furthermore, the inc sleep duration phenotype can be rescued by pharmacological inhibition of tyrosine hydroxylase, the rate-limiting enzyme for dopamine biosynthesis. Taken together, these results establish inc and Cul3 as important new players in setting the sleep homeostat and a dopaminergic arousal pathway in Drosophila. Sleep is an essential behavior that encompasses roughly a third of our lives; however, the underlying function remains a mystery. The fruit fly has emerged as an important model system for understanding sleep behavior, exhibiting several behavioral and genetic similarities with mammalian sleep, including consolidated immobility, an elevation of arousal threshold to a range of stimuli, homeostatic drive, and manipulation by proven stimulants and sedatives. We tested disruptions of candidate sleep genes and identified a gene called insomniac that exhibits one of the strongest and most robust sleep phenotypes to date, including a suppressed homeostatic response to sleep deprivation. We find similar phenotypes for a gene previously shown to interact with inc and a known regulator of protein degradation, Cul3, linking sleep homeostasis to protein turnover. Importantly, we find that insomniac functions in a known arousal system in the brain, as defined by the neurotransmitter dopamine. This work provides an important insight into the genetic basis of sleep homeostasis with the discovery of a new molecular component of a dopaminergic arousal pathway. Given the conservation of fly and mammalian systems, these studies may lead to new insights into the molecules that mediate sleep homeostasis and arousal in humans.
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DOI：
10.1126/science.1202839
发表时间：
2011-06-24
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Bushey D;Tononi G;Cirelli C
通讯作者：
Cirelli C
DOI：
10.1126/science.1166673
发表时间：
2009-04-03
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Gilestro GF;Tononi G;Cirelli C
通讯作者：
Cirelli C
影响因子：
11.4
作者：
Allada, R;Kadener, S;Rosbash, M
通讯作者：
Rosbash, M
影响因子：
3.7
作者：
Djagaeva I;Doronkin S
通讯作者：
Doronkin S
影响因子：
64.8
作者：
Cirelli, C;Bushey, D;Tononi, G
通讯作者：
Tononi, G