mtDNA Rearrangements in Human Development and Disease

描述（由申请人提供）：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，即mtDNA。mtDNA的复制和转录以及mtDNA编码蛋白的翻译对于通过氧化磷酸化产生ATP是必不可少的。对人类线粒体DNA的进化分析和分子生物学研究表明，人类线粒体DNA存在重组现象。在健康个体中，线粒体DNA的重排发生在低水平，并导致线粒体DNA重排的积累，其水平随年龄增长而增加。在高水平上，mtDNA重排可导致线粒体功能障碍和人类疾病。由于缺乏合适的mtDNA标记物来检测重组，因此很难在细胞中实验观察mtDNA重组。这里描述了一个模型系统，它使用独特标记的人类mtDNA，允许检测分子间和分子内的重组mtDNA。该分析系统将用于鉴定mtDNA重组产物并确定其形成速率。随后，将研究重组mtDNA在细胞中形成的机制。这些研究可能会导致对致病性mtDNA重排形成机制的重要见解，以及涉及mtDNA的基本细胞过程，包括mtDNA的维持，复制和修复机制。

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.