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

• 批准号: 8334584
• 负责人: PATRICK H O'FARRELL
• 金额: $ 34.13万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 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/8334584
• 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 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

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，用于破坏线粒体的亚型特异性相互作用 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。