Mitonuclear coordination of gene expression across complex cellular states using mitoribosome profiling

项目摘要/摘要 在细胞内跨核基因组和线粒体基因组的基因表达的协调对于 组成电子传递链的氧化磷酸化(OXPHOS)复合体的正确组装 并使有氧生活成为可能。这种有丝分裂平衡必须由各地的分子参与者紧密协调 细胞隔间，关键是必须适应动态的细胞环境。均衡的基因表达 当我们考虑到复杂的细胞状态时，这些基因组构成了一个独特的挑战，例如老化的细胞 它必须处理蛋白质组的衰退以及其他侮辱或长寿、形态复杂的细胞，如 这种协调能力可能会迅速崩溃的神经元。未能维持适当的有丝分裂核平衡 由此导致的线粒体功能障碍与人类的许多疾病有关，包括 神经退行性疾病和癌症，以及衰老过程本身。 我们的实验室以前已经证明，线粒体和核基因组调控协调基因 需要双来源OXPHOS基因的翻译而不是转录水平的表达程序 在线粒体生物发生过程中建立呼吸复合体。这些研究利用了同时的细胞质 和线粒体核糖体图谱技术，但到目前为止只在健康的中段进行过 相态酵母。我们的长期目标现在是了解线粒体基因组是如何被调控的 跨越不同的细胞状态和生物背景。我们对这项提案的具体目标将帮助我们实现 这些目标有两个：(1)确定细胞环境恶化的影响 使用复制老化酵母的线粒体基因表达和有丝分裂核协调的寿命和(2) 确定在胞体中必须有不同线粒体需求的有丝分裂后神经元的比较 远端神经突能维持适当的有丝分裂核配位，适当调节线粒体基因 在这个长寿和形态复杂的细胞的整个生命周期中表达。总而言之，这项建议 研究将促进我们对线粒体基因调控和细胞内线粒体生物学的了解 与人类疾病和老龄化有关的国家。

PROJECT SUMMARY / ABSTRACT Coordination of gene expression across nuclear and mitochondrial genomes within a cell is crucial for the correct assembly of oxidative phosphorylation (OXPHOS) complexes that make up the electron transport chain and enable aerobic life. This mitonuclear balance must be tightly orchestrated by molecular players across cellular compartments and critically must adapt to a dynamic cellular milieu. Balanced gene expression across these genomes poses a unique challenge when we consider complex cellular states, for example aged cells that must deal with declining proteomes among other insults or long-lived, morphologically complex cells like neurons where this coordination could rapidly breakdown. Failure to maintain proper mitonuclear balance and the resulting mitochondrial dysfunction is implicated in a myriad of human diseases, including neurodegenerative diseases and cancer, as well as the aging process itself. Our lab has previously demonstrated that mitochondrial and nuclear genomes regulate coordinated gene expression programs on the translational but not transcriptional level for dual-origin OXPHOS genes required to build respiratory complexes during mitochondrial biogenesis. These studies utilized simultaneous cytosolic and mitochondrial ribosome profiling techniques, but to date have only been performed in healthy mid-log phase yeast. Our long-term objectives are now to understand how mitochondrial genomes are regulated across diverse cellular states and biological contexts. Our specific aims for this proposal that will help us attain these objectives are twofold: (1) to determine the effects of a deteriorating cellular environment during a cell’s lifespan on mitochondrial gene expression and mitonuclear coordination using replicatively-aged yeast and (2) determine how post-mitotic neurons which must have different mitochondrial demands in the soma compared to distal neurites can maintain proper mitonuclear coordination and appropriately regulate mitochondrial gene expression over the lifespan of this long-lived and morphologically complex cell. In summary this proposed research will advance our knowledge of mitochondrial gene regulation and mitochondrial biology in cellular states with relevance to human disease and aging.