Identifying Cardiomyopathy Genes in Mice and Drosophila

鉴定小鼠和果蝇的心肌病基因

基本信息

批准号：
7141888
负责人：
Howard A Rockman
金额：
$ 38.88万
依托单位：
DUKE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-09-29 至 2010-08-31
项目状态：
已结题

项目摘要

DESCRIPTION (provided by applicant): Genetic approaches, preferentially in model systems that both allow accurate measurement of heart function as well as efficient genetic screening, are necessary for substantial progress in identifying the genetic basis of heart failure. In proposal, we will test the hypothesis that the powerful mutagen, N-ethyl-N- nitrosourea (ENU), mutagenesis in mice, and gene-deletion screens in Drosophila, will lead to the discovery of novel disease-causing and disease-modifying genes for human heart failure. In order to test these hypotheses, we have performed a recessive mutagenesis screen in adult mice at 8 and 16 weeks of age using non-invasive echocardiography to screen for abnormalities in cardiac function and have already identified a heritable region on chromosome 1 that maps to a cardiomyopathic phenotype. To complement the mouse studies we propose to use the fly to identify novel cardiomyopathic genes. Drosophila genetics provides more than 19,000 molecularly-defined P-elements inserted throughout the Drosophila genome that facilitate the generation of high-density genomic coverage. We have developed an innovative approach to phenotype cardiac function in adult awake Drosophila and have identified a P-element mutation in the short gastrulation (sog) gene that results in dilated cardiomyopathy. Based on our preliminary findings, we propose that mouse and Drosophila genetics can identify novel genes and mechanisms that are responsible for human dilated cardiomyopathies. Accordingly, we propose the following specific aims: Aim 1: To identify novel genes causing cardiomyopathy using an ENU phenotype-driven recessive screen in adult mice. We propose to map the disease causing gene located on chromosome 1 in the ENU family with abnormal cardiac function. Aim 2: To investigate the biochemical and genetic mechanisms through which mutations in the dpp/BMP signaling pathway lead to dilated cardiomyopathy in adult Drosophila. Genetic complementation experiments will be performed in Drosophila to prove that sog deficiency causes cardiomyopathy. Aim 3: To test whether decreased antagonism of the BMP pathway in mice, will result in a cardiomyopathic phenotype under conditions of pressure overload. TAG experiments will be performed in knock out mice deficient in the endogenous mammalian BMP antagonists chordin and noggin. Aim 4: To identify novel genes causing cardiomyopathy by performing a genome-wide screen of deletion mutants in Drosophila. Flies heterozygous for PiggyBac derived deletion mutants from the Exelixis collection will be screened for cardiomyopathy using optical coherence tomography followed by fine mapping of the disease-causing gene(s). Thus, these four integrated aims will harness the power of mouse and Drosophila genetics to identify and evaluate novel candidate genes for their role in cardiomyopathy.

描述（由申请人提供）：在模型系统中优先允许精确测量心脏功能以及有效的遗传筛查，对于识别心脏衰竭的遗传基础是必不可少的进展，遗传方法优先。在提案中，我们将检验以下假设：强大的诱变剂N-乙基-N-硝酸盐（ENU），小鼠中的诱变以及果蝇中的基因 - 缺失筛查将导致发现新型引起疾病的疾病和疾病疾病基因的人类心脏故障。为了检验这些假设，我们使用非侵入性超声心动图在成年小鼠的成年小鼠中进行了隐性诱变筛查，以筛选心脏功能异常的筛查，并已经确定了1号染色体上可遗传的区域，该区域将其映射到心肌病态型。为了补充小鼠研究，我们建议使用果蝇鉴定新型心肌病基因。果蝇遗传学提供了整个果蝇基因组中插入的19,000多个分子定义的P元素，可促进高密度基因组覆盖率的产生。我们已经开发了一种创新的方法来在成年绿色果蝇中表型心脏功能，并确定了短胃（SOG）基因中的P元素突变，从而导致心肌病扩张。根据我们的初步发现，我们建议小鼠和果蝇遗传学可以鉴定出负责人扩张心肌病的新型基因和机制。因此，我们提出了以下特定目的：目标1：使用成年小鼠中使用ENU表型驱动的隐性筛查来鉴定引起心肌病的新基因。我们建议绘制疾病，导致基因位于心脏功能异常的ENU家族中的1号染色体上。目标2：研究生化和遗传机制，通过这些机制，DPP/BMP信号传导途径中的突变导致成年果蝇的心肌病扩张。遗传互补实验将在果蝇中进行，以证明SOG缺乏会导致心肌病。目标3：为了测试小鼠BMP途径的拮抗作用是否减少，在压力超负荷条件下会导致心肌病的表型。 TAG实验将在敲除内源性哺乳动物BMP拮抗剂Chordin和Noggin缺乏的小鼠中进行。 AIM 4：通过在果蝇中进行全基因组缺失突变体的全基因组筛选来鉴定引起心肌病的新基因。从Exelixis收集中衍生出的缺失突变体的果冻将使用光学相干性层析成像进行筛查以进行心肌病，然后对疾病引起疾病的基因进行精细映射。因此，这四个综合目标将利用小鼠和果蝇遗传学的力量识别和评估新型候选基因在心肌病中的作用。