Biogenesis of mitochondrial apoptotic proteins

除了在新陈代谢中起中心作用外，线粒体在细胞凋亡/程序化细胞中也起着关键作用 死亡。线粒体膜间间隙是几种凋亡成分的所在地，这些成分介导了 蛋白质(细胞色素c、Smac/Diablo、HtrA2/OMI)、DNA(凋亡诱导因子)、 和核酸内切酶G)，根据我们目前的研究，RNA(PNPase)。许多促和抗细胞凋亡的蛋白质 Bcl2/Bax家族的部分基因定位于线粒体外膜。此外，蛋白质通常 常驻到其他亚细胞隔室，如Nur77和Mud/也以线粒体为靶标 在细胞凋亡过程中。线粒体的驻留蛋白遵循非常特殊的途径输入和 在细胞器中组装。据推测，这些凋亡蛋白利用特定的生物发生途径 对于它们在细胞凋亡中的高度调控作用非常重要。这项提案的目标是使用组合的 分离的线粒体、酿酒酵母、细胞培养和动物模型中的遗传和生化方法 研究线粒体膜间隙凋亡蛋白的生物发生。第一个目标 这项提案的目的是根据以下情况确定各类别代表的进口途径 降解的目标(即DNA、蛋白质或RNA)，从PNPase开始。第二个目标是 研究PNPase在膜间隙的组装和释放。最终目标是 研究PNPase在维持呼吸中的作用及其与细胞凋亡的关系 破坏氧化磷酸化，降低膜电位。与之前的研究相反， 主要集中在单个组件上，本提案将专门侧重于事件 与线粒体膜间间隙中的凋亡蛋白的生物发生有关，从而提供 对这个隔室在程序性细胞死亡中的作用的新见解。我们将确定是否不同 凋亡蛋白可能分享保守的生物发生途径，这可能是理想的靶点 开发一种新的方法来同时调节几种细胞凋亡途径。此应用程序具有 对公共健康的更广泛影响，因为与细胞凋亡有关的线粒体事件导致癌症 和神经退行性疾病。

In addition to a central role in metabolism, mitochondria play a critical role in apoptosis/programmed cell death. The mitochondrial intermembrane space is home to several apoptotic components that mediate the degradation of proteins (cytochrome c, Smac/DIABLO, HtrA2/OMI), DNA (apoptosis inducing factor (AIF), and Endonuclease G), and, from our current studies, RNA (PNPase). Many pro- and anti-apoptotic proteins of the Bcl-2/Bax family are targeted to the mitochondrial outer membrane. Additionally, proteins normally resident to other subcellular compartments, such as Nur77 and Mud /are also targeted to mitochondria during apoptosis. Resident proteins of the mitochondrion follow very specific pathways for import and assembly in the organelle. Presumably, these apoptotic proteins utilize specific pathways for biogenesis that are important for their highly regulated role in apoptosis. The goal of this proposal is to use a combined genetic and biochemical approach in isolated mitochondria, S. cerevisiae, cell culture, and animal models to characterize the biogenesis of the mitochondrial intermembrane space apoptotic proteins. The first objective of this proposal is to characterize the import pathway of representatives in the various categories, based on the target of degradation (ie., DNA, protein, or RNA), beginning with PNPase. The second objective is to investigate the assembly and release of PNPase from the intermembrane space. The final objective is to investigate the role of PNPase in maintaining respiration and its link to apoptosis because loss of PNPase disrupts oxidative phosphorylation and lowers the membrane potential. In contrast to previous studies that have focused primarily on the individual components, this proposal will focus specifically on the events related to the biogenesis of apoptotic proteins in the mitochondrial intermembrane space and thus provide novel insights into the role of this compartment in programmed cell death. We will determine if the different apoptotic proteins might share conserved biogenesis pathways, which could be an ideal target for the development of new approaches to modulate several apoptotic pathways at one time. This application has a broader impact in public health because the mitochondrial events linked to apoptosis contribute to cancer and neurodegenerative diseases.