Functional analysis of a non-coding RNA in the mammalian circadian clock system

哺乳动物生物钟系统中非编码RNA的功能分析

• 批准号: 10250353
• 负责人: Shihoko Kojima
• 金额: $ 32.53万
• 依托单位: VIRGINIA POLYTECHNIC INST AND ST UNIV
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10250353
• 关键词: Address; Animals; Antheraea; Antisense RNA; Behavior; Biochemistry; Biological; Biological Clocks; Biological Process; Biology; Cells; Characteristics; Consumption; Data; Feedback; Genes; Genetic Transcription; Goals; Health; Human; Jet Lag Syndrome; Knowledge; Lead; Light; Limb structure; Mammals; Mathematics; Messenger RNA; Modernization; Molecular; Names; Neurospora crassa; Noise; Outcome; Outcome Study; Output; Pathologic; Pattern; Periodicity; Phase; Physiological; Physiology; Play; Proteins; Regulation; Regulator Genes; Reporting; Role; Specificity; System; Testing; Therapeutic; Tissues; Transcript; Translations; Untranslated RNA; Work; base; circadian; circadian pacemaker; circadian regulation; design; gain of function; insight; lifestyle factors; loss of function; mathematical methods; molecular clock; novel; shift work; transcriptome

Circadian rhythmicity is a fundamental aspect of the temporal organization of cells in the body, and it modulates much of biochemistry, physiology, behavior, and pathological state. Essentially every cell in the body is capable of generating circadian rhythmicity in mammals, and within each cell, a set of clock genes (which are highly conserved among animals) form transcription–translation feedback loops that drive circadian oscillation. Even though the molecular basis of circadian rhythmicity is thought to be well-characterized, recent transcriptome analyses identified a novel transcript that appears to play an interesting role in these core clock loops. This transcript, Per2AS, is a natural antisense transcript, a class of non-coding RNAs (ncRNAs), of Period2 (Per2), one of the core clock genes. Per2AS is transcribed from the strand opposite to Per2 and its expression is rhythmic and antiphasic to Per2. Given that Per2AS expression is rhythmic and antiphasic to its sense partner and that rhythmic transcription is more energy-consuming than non-rhythmic transcription, it is hypothesized that Per2AS is a functional molecule and plays an important role in the mammalian circadian clock system. Even though ncRNAs were originally considered to be mere transcriptional noise and lack defined functions, a few dozen examples have expanded the scope of ncRNAs from mere “junk” to functional molecules having a wide spectrum of regulatory roles. In fact, antisense transcripts of a core clock gene have been reported in Neurospora crassa and Antheraea pernyi and been shown to confer robust and sustained rhythmicity, implying that sense-antisense interactions of a core clock gene constitute a common mechanism for circadian clock regulation across kingdoms. Three specific aims have been designed to test our central hypothesis and define the biological function of Per2AS in the mammalian circadian clock system. The first aim addresses whether the presence, rhythmicity, and phase of Per2AS expression relative to Per2 are biologically significant. The second aim takes advantage of traditional strategies and directly asks whether perturbations of Per2AS expression result in changes in the circadian clock machinery. The third aim, based on our preliminary data, focuses on specific molecules that Per2AS may regulate in order to shed light on the molecular function(s) of Per2AS. Successful completion of this study not only advances our knowledge of circadian biology but also of regulatory ncRNAs. Only in relatively few cases have interactions between sense and antisense RNA pairs been explored and the physiological importance and mode-of-action of these pairs remain poorly understood. Outcomes from the proposed project will have significant impact in understanding the role of antisense transcripts and shed light on the molecular mechanisms by which antisense transcripts elicit physiological functions without producing a protein. Deepening the understanding of the clock oscillatory mechanism and how a non-coding gene (i.e., Per2AS) contributes to the clock output will help us to, ultimately, develop therapeutics for people who suffer from disrupted internal clocks.

昼夜节律性是体内细胞时间组织的一个基本方面，它 调节许多生化、生理、行为和病理状态。基本上，每个单元格都在 哺乳动物的身体能够产生昼夜节律，在每个细胞内，有一组时钟基因 (在动物中高度保守)形成转录-翻译反馈环，驱动昼夜节律 振荡性。尽管昼夜节律性的分子基础被认为具有很好的特性，但最近 转录组分析发现了一个新的转录本，它似乎在这些核心时钟中扮演着有趣的角色 循环。这个转录本，Per2AS，是一种天然的反义转录本，是一类非编码RNA(NcRNAs)， Perdio2(PER2)，核心时钟基因之一。Per2AS是从与PER2相反的链转录而来的，其 表达是有节律性的，与PER2相反。鉴于Per2AS的表达是有节律性的且与其相反 且有节奏转录比非有节奏转录更耗能， 假设Per2AS是一个功能分子，并在哺乳动物的昼夜节律中发挥重要作用 时钟系统。尽管ncRNAs最初被认为仅仅是转录噪音和缺乏 在定义的函数中，几十个例子已经将ncRNA的范围从纯粹的“垃圾”扩展到了功能性 具有广泛调节作用的分子。事实上，核心时钟基因的反义转录本已经 在粗糙脉孢菌和Antheraea pernyi中已有报道，并被证明具有强大和持续的能力 节律性，意味着核心时钟基因的正义-反义相互作用构成了一种共同的机制 各王国的生物钟调节。我们设计了三个具体的目标来测试我们的中央 假设并定义Per2AS在哺乳动物生物钟系统中的生物学功能。第一个目标 解决与PER2相关的Per2AS表达的存在、节律性和阶段是否具有生物学意义 意义重大。第二个目的是利用传统策略，直接询问扰动是否 Per2AS的表达导致了生物钟机械的变化。第三个目标，基于我们初步的 数据，集中在Per2AS可能调节的特定分子上，以阐明分子 功能(S)的Per2AS。这项研究的成功完成不仅提高了我们对昼夜节律的认识 不仅是生物学上的，而且还有调控的ncRNA。只有在相对较少的情况下，Sense和Sense之间存在交互作用 已经探索了反义RNA对，这些对的生理重要性和作用模式仍然存在 人们对此知之甚少。拟议项目的结果将对理解该角色产生重大影响 并阐明了反义转录物引发的分子机制 生理功能而不产生蛋白质。加深对钟摆现象的认识 机制以及非编码基因(即Per2AS)如何对时钟输出做出贡献将最终帮助我们， 为体内生物钟紊乱的人开发治疗方法。