The genetic basis for tissue specific sensitivities to mitochondrial stress

组织对线粒体应激特异性敏感性的遗传基础

基本信息

批准号：
8691817
负责人：
PATRICK H O'FARRELL
金额：
$ 34.41万
依托单位：
UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-09-19 至 2016-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8691817
关键词：
Address Affect Alleles Biosensor Blindness Cause of Death Cells Chemicals Complex DNA Sequence Defect Development Diagnosis Disease Dose Drosophila genus Ectopic Expression Engineering Environment Environmental Risk Factor Experimental Models Exposure to Eye Failure Fertility Functional disorder Gene Mutation Genes Genetic Genetic Engineering Genetic Models Genetic Polymorphism Goals Growth Health Healthcare Human Hypertrophy Lead Mammals Mitochondria Modeling Mutate Mutation Mutation Detection Nature Nuclear Oligomycins Oxidative Phosphorylation Parkin gene Pharmaceutical Preparations Phenotype Point Mutation Population Protein Isoforms Proteins Provider RNA Interference Respiratory Chain Role Rotenone Specificity Sterility Stress Syndrome Testing Testis Tissues Toxic effect Toxicant exposure Toxin Ursidae Family Work base cell growth cell transformation cell type chemical genetics cytochrome c cytochrome c oxidase empowered environmental chemical fly improved inhibitor/antagonist male mitochondrial dysfunction mitochondrial genome mutant novel strategies prevent research study sensor stressor tool toxicant transdetermination tumor progression

项目摘要

ABSTRACT Our goal is to understand how mutations and inhibitors that disrupt general mitochondrial functions can cause syndromes with marked tissue specificity. We are developing new experimental models in which we can bring the powerful genetic tools in Drosophila to bear on this question. We will test whether the tissue specificity of genetic and chemical stressors occurs because they target interactions between general mitochondrial functions and tissue specific genes. A particular mutant of Drosophila Cytochrome oxidase subunit 1 is male sterile, and otherwise normal. We hypothesize that this highly specific phenotype is the result of a failure of this allele to work conjunction with a testis specific isoform of one of the other respiratory chain proteins. Indeed, ectopic expression of the somatic version of Cytochrome c in the testis suppresses the sterility phenotype. The proposed experiments will rigorously test whether this sterility is due to a specific deficit in the partnership of the mutant Cytochrome oxidase and the testis specific isoform of Cytochrome c. Additionally, we will engineer the fly eye as a biosensor for disruption of isoform-specific interactions of mitochondrial functions, and will apply it to identify mutations and chemicals interfering with these interactions. We will also explore tissue specificity resulting from a synergy of two defects, where a tissue specific defect sensitizes a tissue to diverse genetic and chemical stressors. Eye specific knockdown of E2F compromised growth to produce a slightly reduced eye. It also sensitized the eye to mitochondrial stress. A low dose of oligomycin that is without notable effect in other tissues, synergizes with E2F:RNAi in the eye to produce tissue transformations (e.g. antennae growing out of the eye) and hypertrophy. We hypothesize that this dysgenesis/hypertrophy relies on two inputs with a biologically universal relationship. Any mutation that inhibits growth of a specific tissue creates a selective environment favoring cells that can escape the growth limitation by transforming to another cell type (transdetermination). A second stress that destabilizes developmental fate would produce the fodder for this selection. Mitochondrial stress appears to provide this destabilizing input. We will test this model and screen for natural mutations and environmental chemicals contributing to the synergizing inputs. Since mammals express numerous proteins as tissue-specific isoforms, they carry many genes that can mutate to create a selection for transdetermination. Without synergizing input, these mutations would have little impact and could accumulate. Thus, we suspect that the human population has a large and insidious pool of "polymorphisms" that creates a diversity of chemical sensitivities. Recognition of sensitizing mutations should empower application of DNA sequencing to personalized health-care.

抽象的我们的目标是了解破坏一般线粒体功能的突变和抑制剂如何导致具有明显组织特异性的综合征。我们正在开发新的实验模型，我们可以将果蝇中强大的遗传工具可以解决这个问题。我们将测试是否具有组织特异性遗传和化学应激源的发生是因为它们针对一般线粒体之间的相互作用功能和组织特异性基因。果蝇细胞色素氧化酶亚基 1 的特殊突变体是雄性无菌，其他正常。我们假设这种高度特异性的表型是失败的结果该等位基因与其他呼吸链蛋白之一的睾丸特异性亚型结合使用。事实上，睾丸中细胞色素 c 体细胞的异位表达抑制了不育表型。拟议的实验将严格测试这种不育是否是由于突变细胞色素氧化酶和细胞色素 c 睾丸特异性亚型的伙伴关系。此外，我们将把蝇眼设计成生物传感器，用于破坏线粒体的异构体特异性相互作用功能，并将应用它来识别突变和干扰这些相互作用的化学物质。我们还将探索两种缺陷协同作用产生的组织特异性，其中组织特异性缺陷使组织对不同的遗传和化学应激源敏感。 E2F 的眼睛特异性敲低受到损害生长产生稍微缩小的眼睛。它还使眼睛对线粒体压力敏感。低剂量寡霉素对其他组织没有显着影响，与眼睛中的 E2F:RNAi 协同产生组织转变（例如触角从眼睛中长出来）和肥大。我们假设这发育不全/肥大依赖于具有生物学普遍关系的两种输入。任何抑制的突变特定组织的生长创造了有利于细胞逃避生长限制的选择性环境通过转化为另一种细胞类型（转决定）。破坏发育命运的第二种压力将为这次选择提供饲料。线粒体应激似乎提供了这种不稳定的输入。我们将测试这个模型并筛选自然突变和环境化学物质，这些化学物质有助于协同投入。由于哺乳动物以组织特异性亚型的形式表达大量蛋白质，因此它们携带许多可以突变以产生转决定选择的基因。如果没有协同输入，这些突变影响很小并且可能会累积。因此，我们怀疑人口数量庞大且阴险的“多态性”池创造了多种化学敏感性。敏化的识别突变应该能够将 DNA 测序应用于个性化医疗保健。