Analysis of nonsense mediated mRNA decay in Drosophila

果蝇中无义介导的 mRNA 衰减分析

基本信息

批准号：
8225334
负责人：
Mark M Metzstein
金额：
$ 26.55万
依托单位：
UNIVERSITY OF UTAH
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-05-05 至 2014-02-28
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): Organisms have evolved a number of molecular surveillance pathways to monitor and prevent cellular damage. One such system is the nonsense mediated decay (NMD) pathway. NMD functions to detect mRNAs with premature termination codons, such as occur in many inherited diseases, and target these mRNAs for rapid degradation and prevent the generation of truncated mutant proteins. However, NMD can exacerbate the effects of many inherited mutations: by targeting and degrading transcripts that otherwise would encode proteins with sufficient biochemical activity for normal function, the NMD pathway can essentially cause a complete loss of activity, and a subsequent disease. Thus inhibition of NMD has potential therapeutic benefit. However, NMD is an essential process in higher animals, including mammals, indicating the NMD pathway has important functions in normal cell biology. These functions are not well understood. Therefore, while NMD-inhibition therapies hold promise for treating certain genetic diseases, realizing this potential will require understanding the biological roles of NMD. To address this important question, we are using Drosophila to study the requirements for NMD during normal development and physiology. Specifically, we plan to determine whether NMD function is required in all tissues for organismal viability and identify the key targets mediating the biological roles of the NMD pathway in critical tissues. We are also using Drosophila to identify the cis-acting signals and trans-acting protein machinery that mediate NMD. We will identify cis-acting sequences directing endogenous targets for NMD-mediated degradation by combining microarray analysis of Drosophila NMD mutants with detailed bioinformatic analysis. To identify trans-acting components, we will use the genetic tools available in Drosophila to conduct efficient, large-scale genetic screens directed at identifying mutations that affect NMD. The screens are designed to identify novel components of the pathway, including those required for organismal viability. The screens will also identify new mutations in known NMD components, which will help define the molecular interactions among these components. Since the NMD pathway is conserved throughout evolution it is likely that the knowledge gained from these approaches will be applicable across a broad range of organisms, including humans.

描述（由申请人提供）：生物已经进化了许多分子监测途径，以监测和防止细胞损伤。这样的系统是胡说八道的介导（NMD）途径。 NMD的功能可检测具有过早终止密码子的mRNA，例如在许多遗传性疾病中发生，并靶向这些mRNA以快速降解并防止产生截短的突变蛋白。但是，NMD可以加剧许多遗传突变的影响：通过靶向和降解转录本，否则将对正常功能进行足够的生化活性编码蛋白质，NMD途径基本上可能导致活动的完全丧失，并随后疾病。因此，抑制NMD具有潜在的治疗益处。然而，NMD是包括哺乳动物在内的高等动物的重要过程，表明NMD途径在正常细胞生物学中具有重要功能。这些功能尚未很好地理解。因此，尽管NMD抑制疗法有望治疗某些遗传疾病，但意识到这种潜力将会需要了解NMD的生物学作用。为了解决这个重要的问题，我们正在使用果蝇在正常发育和生理学期间研究NMD的要求。具体而言，我们计划确定在所有组织中是否需要NMD功能才能实现生存力，并确定介导NMD途径在关键组织中的生物学作用的关键靶标。我们还使用果蝇来识别介导NMD的顺式作用信号和跨作用蛋白机制。我们将通过将果蝇NMD突变体的微阵列分析与详细的生物信息学分析相结合，从而确定指导内源性靶标的NMD介导的降解的顺式作用序列。为了识别跨作用成分，我们将使用果蝇中可用的遗传工具来进行有效的大规模遗传筛选，该筛选针对识别影响NMD的突变。屏幕旨在识别途径的新成分，包括生存能力所需的途径。屏幕还将在已知的NMD成分中识别新的突变，这将有助于定义这些组件之间的分子相互作用。由于NMD途径在整个进化过程中都保存下来，因此从这些方法中获得的知识很可能适用于包括人类在内的各种生物体。