Mitochondrial Fusion and Division

描述（由申请人提供）：线粒体是动态的膜细胞器，以高度调节的方式进行分裂和融合。这些相反的活动之间的平衡在控制线粒体结构和功能中起着关键作用。线粒体 分裂和融合由保守的动力蛋白相关GTP酶介导，所述保守的动力蛋白相关GTP酶包括用于分裂的动力蛋白相关蛋白1（Drp 1）和用于融合的线粒体融合蛋白和视神经萎缩1（Opa 1）。由于正在进行的融合，线粒体分裂的抑制会增加线粒体的大小，而融合的抑制会导致线粒体的碎片化。线粒体分裂和融合的异常与许多神经退行性疾病相关，例如常染色体显性视神经萎缩、Charcot-Marie-Tooth神经病、阿尔茨海默病、亨廷顿病和帕金森病。了解这些疾病的发病机制需要更深入地了解线粒体动力学的分子机制。在这项拟议的研究中，我们将鉴定和表征与中央线粒体分裂蛋白Drp 1结合并调节的新蛋白。我们一直在开发创新的方法来实现这一目标，通过结合两种技术-体外蛋白质-蛋白质相互作用分析使用功能蛋白质微阵列和体内蛋白质-蛋白质相互作用分析使用化学诱导的异源二聚化系统组成的两种蛋白质，FK 506结合蛋白（FKBP）和雷帕霉素结合结构域的mTOR（FRB）。使用蛋白质芯片，我们进行了全基因组搜索，并确定了18个Drp 1结合蛋白。在本修订版中，我们将使用FBP-FRB异源二聚化系统验证它们与活细胞中Drp 1的相互作用。最后，我们将使用基因敲低方法确定它们在线粒体分裂中的功能重要性。因此，这项研究将提供一个新的线粒体分裂机制的见解。

DESCRIPTION (provided by applicant): Mitochondria are dynamic membrane organelles that undergo division and fusion in highly regulated manners. The balance between these opposing activities plays a critical role in controlling mitochondrial structure and function. Mitochondrial division and fusion are mediated by conserved dynamin-related GTPases that include dynamin-related protein 1 (Drp1) for division, and mitofusin and optic atrophy 1 (Opa1) for fusion. Inhibition of mitochondrial division increases the size of the mitochondria due to ongoing fusion, whereas inhibition of fusion leads to fragmentation of the mitochondria. Abnormalities in mitochondrial division and fusion are associated with many neurodegenerative diseases, such as autosomal dominant optic atrophy, Charcot-Marie-Tooth neuropathy, Alzheimer's disease, Huntington's disease, and Parkinson's disease. Understanding the pathogenesis of these diseases requires a deeper knowledge of the molecular mechanism of mitochondrial dynamics. In this proposed research, we will identify and characterize novel proteins that bind to and regulate the central mitochondrial division protein Drp1. We have been developing innovative approaches to achieve this goal by combining two technologies - in vitro protein-protein interaction analysis using functional protein microarrays and in vivo protein-protein interaction analysis using the chemically inducible hetero-dimerization system consisting two proteins, the FK506-binding protein (FKBP) and the rapamycin-binding domain of mTOR (FRB). Using protein microarrays, we have performed a genome- wide search and identified 18 Drp1-binding proteins. In this revision, we will validate their interactions with Drp1 in live cells using the FBP-FRB hetero-dimerization system. Finally, we will determine their functional importance in mitochondrial division using gene knockdown approaches. Therefore, this study will provide a novel mechanistic insight into mitochondrial division.