Department of Biochemistry, University of Regina, Regina, SK S4S 0A2, Canada.
Department of Computer Science, University of Regina, Regina, SK S4S 0A2, Canada.
Cell Syst. 2017 Dec 27;5(6):564-577.e12. doi: 10.1016/j.cels.2017.10.010. Epub 2017 Nov 8.
Mitochondrial protein (MP) dysfunction has been linked to neurodegenerative disorders (NDs); however, the discovery of the molecular mechanisms underlying NDs has been impeded by the limited characterization of interactions governing MP function. Here, using mass spectrometry (MS)-based analysis of 210 affinity-purified mitochondrial (mt) fractions isolated from 27 epitope-tagged human ND-linked MPs in HEK293 cells, we report a high-confidence MP network including 1,964 interactions among 772 proteins (>90% previously unreported). Nearly three-fourths of these interactions were confirmed in mouse brain and multiple human differentiated neuronal cell lines by primary antibody immunoprecipitation and MS, with many linked to NDs and autism. We show that the SOD1-PRDX5 interaction, critical for mt redox homeostasis, can be perturbed by amyotrophic lateral sclerosis-linked SOD1 allelic variants and establish a functional role for ND-linked factors coupled with IκBɛ in NF-κB activation. Our results identify mechanisms for ND-linked MPs and expand the human mt interaction landscape.
线粒体蛋白 (MP) 功能障碍与神经退行性疾病 (NDs) 有关；然而，由于对控制 MP 功能的相互作用的有限描述，NDs 发病机制的发现一直受到阻碍。在这里，我们使用基于质谱 (MS) 的分析，对 27 种与人 ND 相关的 MP 进行了 210 次亲和纯化的线粒体 (mt) 级分的分析，这些级分来自 HEK293 细胞中的 210 种表位标记的人类 ND 相关 MP，我们报告了一个高可信度的 MP 网络，包括 772 种蛋白质之间的 1964 个相互作用（>90%以前未报道过）。这些相互作用中有近四分之三通过小鼠大脑和多种人类分化神经元细胞系的初级抗体免疫沉淀和 MS 得到了证实，其中许多与 NDs 和自闭症有关。我们表明，SOD1-PRDX5 相互作用对于 mt 氧化还原稳态至关重要，可被肌萎缩侧索硬化症相关 SOD1 等位基因变体破坏，并建立了与 ND 相关的因素与 NF-κB 激活中的 IκBɛ 相关的功能作用。我们的研究结果确定了 ND 相关 MPs 的机制，并扩展了人类 mt 相互作用图谱。
