Transfer of Organelle Genes to the Nucleus

将细胞器基因转移到细胞核

• 批准号: 6635926
• 负责人: JEFFREY D PALMER
• 金额: $ 37.82万
• 依托单位: TRUSTEES OF INDIANA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-09-01 至 2005-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6635926
• 关键词: Arabidopsis; DNA directed RNA polymerase; angiosperms; biochemical evolution; cell nucleus; cytochrome oxidase; cytogenetics; developmental genetics; gene duplication; gene expression; gene induction /repression; gene mutation; genetic transcription; genome; introns; microarray technology; mitochondria; molecular cloning; nucleic acid hybridization; nucleic acid sequence; organelles; plant genetics; plant morphology; polymerase chain reaction; protein structure function

DESCRIPTION (Applicant's Abstract) The study of organelle genes is essential to our understanding of eukaryotic cellular and molecular biology. The proper functioning of organelles in eukaryotic cells involves a precise cooperation between nuclear and organellar genetic systems. Defects in this functioning have direct consequences for human health, as is evident from the intense interest in mitochondrially-inherited diseases. The primary goal of this proposal is to address a fundamental problem in the genetic coevolution of the eukaryotic cell: How are organelle genes functionally transferred to the nucleus during evolution, and what are the tempo, pattern, and consequences of these genetic relocations? All of this work is carried out in plants, which for several reasons should be viewed as a model to study functional gene transfer from organelles to nucleus. We propose to: 1) use DNA hybridization arrays to survey 20,000 species of plants in order to elucidate the fine-scale tempo and pattern of loss (and gain) of mitochondrial genes and introns, and to use these findings as the starting point for many of the more in-depth studies outlined below; 2) test, for several mitochondrial genes, the hypothesis that their many separate losses reflect remarkably high rates of functional gene transfer to the nucleus, and in so doing, to learn more about the mechanisms of functional gene transfer; 3) examine a few cases of gene transfer in-depth in order to characterize intermediate stages of transcompartmental duplication, to determine their persistence and the dynamics of mitochondrial vs. nuclear gene loss and silencing, and to investigate whether transcompartmental duplications are ever fixed; 4) identify plants with highly elevated rates of ongoing gene transfer and test the hypothesis that this is caused by highly elevated rates of reverse transcription; 5) determine whether mitochondrial genomes ever reacquire genes lost through transfer to the nucleus, and if so, whether this occurs by direct return from the nucleus of the same organism, or by lateral transfer from an unrelated organism; and. Our secondary goal is to determine the origin and pattern of transmission of an extraordinarily invasive genetic element - a homing group I intron that we showed has invaded mitochondrial coxi genes over 1,000 times through a massive wave of lateral transfers during recent angiosperm evolution.

描述(申请人的摘要)细胞器基因的研究对 我们对真核细胞和分子生物学的理解。适当的 真核细胞中细胞器的功能需要精确的合作 在核遗传系统和细胞器遗传系统之间。这一功能的缺陷 对人类健康有直接影响，从强烈的 对线粒体遗传性疾病的兴趣。这样做的主要目标是 该提案旨在解决生物遗传共同进化中的一个基本问题 真核细胞：细胞器基因是如何功能转移到 进化过程中的核心，以及它的节奏、模式和后果是什么 这些基因重排？所有这些工作都是在植物中进行的，为了 几个原因应该被视为研究功能性基因转移的模型 从细胞器到细胞核。 我们建议：1)使用DNA杂交阵列调查20,000个物种 植物，以阐明细微尺度的损失速度和模式(和 获得)线粒体基因和内含子，并将这些发现作为 下面概述的许多更深入研究的起点；2)测试， 对于几个线粒体基因来说，他们的许多独立丢失的假设 反映出功能基因转移到细胞核的比率非常高，以及 通过这样做，了解更多关于功能性基因转移的机制；3) 深入研究几个基因转移案例，以确定其特征 跨间隔复制的中间阶段，以确定其 线粒体与核基因丢失的持续性和动力学 沉默，并调查是否存在跨间隔复制 修复；4)识别正在进行的基因转移率极高的植物 并测试这一假设，即这是由极高的反转率造成的 转录；5)确定线粒体基因组是否会重新获得基因 通过转移到原子核而丢失，如果是，这种情况是否直接发生 从同一生物体的核返回，或通过横向转移从一个 不相关的生物体；以及。我们的次要目标是确定原点和 一种极具侵袭性的遗传元素-a的传播模式 我们发现的归巢I组内含子已经入侵了线粒体Coxi基因 1,000次通过大规模的横向转移浪潮在最近 被子植物的进化。