mtDNA Rearrangements in Human Development and Disease

描述(申请人提供)：线粒体在真核细胞的细胞器中是不寻常的，因为它们拥有自己的基因组，线粒体DNA。线粒体DNA的复制和转录以及线粒体DNA编码蛋白的翻译对于氧化磷酸化产生ATP是必不可少的。人类线粒体DNA的进化分析和分子研究表明，人类线粒体DNA发生了重组。线粒体DNA的重组发生在健康个体中的低水平，并导致线粒体DNA重排的积累，其水平随着年龄的增加而增加。在高水平下，线粒体DNA重排可能导致线粒体功能障碍和人类疾病。由于缺乏合适的mtDNA标记来检测重组，在细胞内实验观察mtDNA重组是困难的。这里描述了一种使用唯一标记的人类mtDNA的模型系统，该mtDNA允许检测分子间和分子内重组mtDNA。这一分析系统将用于鉴定线粒体DNA重组的产物，并确定它们的形成率。随后，将研究重组mtDNA在细胞中形成的机制。这些研究可能导致对致病性线粒体DNA重排的形成机制以及涉及线粒体DNA的基本细胞过程，包括线粒体DNA的维持、复制和修复机制的重大洞察。

DESCRIPTION (provided by applicant): Mitochondria are unusual among the organelles of a eukaryotic cell in that they possess their own genome, the mtDNA. The replication and transcription of mtDNA and the translation of the mtDNA-encoded proteins is essential for the production of ATP by oxidative phosphorylation. Evolutionary analyses and molecular studies of human mtDNA indicate that recombination of human mtDNA occurs. Recombination of mtDNA occurs at low levels in healthy individuals and results in the accumulation of mtDNA rearrangements, whose levels increase with age. At high levels, mtDNA rearrangements can result in mitochondrial dysfunction and human disease. It is difficult to observe mtDNA recombination experimentally in cells because of the lack of appropriate mtDNA markers to detect recombination. A model system is described here that uses uniquely marked human mtDNAs that permit the detection of inter-molecular and intra-molecular recombinant mtDNAs. This system of analysis will be used to identify the products of mtDNA recombination and to determine their rates of formation. Subsequently, the mechanisms by which recombinant mtDNAs are formed in cells will be investigated. These investigations are likely to lead to significant insights into the mechanism for formation of pathogenic mtDNA rearrangements, as well as into fundamental cellular processes involving mtDNA including mtDNA maintenance, replication, and repair mechanisms.