Regulation of Mitochondrial DNA

线粒体在细胞功能中的作用越来越被研究人员所认识。线粒体编码自己的基因组（mtDNA），这是一种对其功能至关重要的分子。尽管第一次描述是在50多年前，但关于mtDNA是如何维持和表达的许多问题仍然存在。作为一名研究线粒体调控基本机制的研究者，我新成立的项目将探索mtDNA调控。除了研究线粒体和mtDNA的传统方法外，我们将利用我们开发的新方法将DNA转染到线粒体中。利用我们在mtDNA和线粒体细胞生物学方面的专业知识，拟议的研究包括三个目标，总体目标是了解蛋白质和序列元件如何调节mtDNA。

The role that mitochondria play in cellular function is increasingly being recognized by researchers. Mitochondria encode their own genome (mtDNA), a molecule that is essential for their function. Although first described over 50 years ago, many questions remain about how mtDNA is maintained and expressed. As a researcher studying the basic mechanisms regulating mitochondria, my newly established program will explore mtDNA regulation. In addition to traditional means of studying mitochondria and mtDNA, we will utilize novel methods we have developed to transfect DNA into mitochondria. Taking advantage of our expertise in mtDNA and mitochondrial cell biology, the proposed research comprises three aims with an overall goal of understanding how proteins and sequence elements regulate mtDNA. Aim 1: To determine how the balanced expression of mtDNA is controlled The relative rates of transcription from the three mitochondrial promoters balances mitochondrial gene expression, mtDNA replication, and mitochondrial ribosome biogenesis. We will determine how the relative rates of mitochondrial transcription are regulated by examining the roles of mitochondrial transcription factors and mtDNA sequences. Additionally, we will examine how signaling pathways affecting mitochondrial transcription alter the balance of mitochondrial expression and also determine the functional consequences of altering this balance. Aim 2: To test the role of mtDNA sequence elements in cells Our novel methods for transfecting DNA into mitochondria allow us for the first time to test the cellular relevance of mtDNA sequence elements. Instead of directly manipulating mtDNA, which is currently not possible, we will transfect a plasmid containing mtDNA regulatory elements, which can be engineered. Determining which structural elements are required for the maintenance of this plasmid will lead to novel understanding about how the mtDNA is regulated. Aim 3: To uncover novel roles of nuclear transcription factors in mitochondria While nuclear transcription factors (NTFs) have been reported in mitochondria, their roles remain largely undefined. Whether NTFs play a direct role in mitochondrial transcription is a matter of debate, as it is difficult to separate their nuclear and mitochondrial functions. We will test this issue by targeting these transcription factors directly to mitochondria and determining their effects on mitochondrial function. Novelty and Significance Our studies, which are an extension of our previously work, will advance our basic understanding of mitochondrial function by answering fundamental questions about the regulation of mtDNA. Improving our basic understanding of mitochondria will have an impact at both the cellular and organismal level and is also relevant to animal health. This research program will also provide a training venue for the next wave of mitochondrial researchers.