School of Molecular Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, WA 6009, Australia.
Biochem Soc Trans. 2022 Jun 30;50(3):1119-1132. doi: 10.1042/BST20220195.
Mitochondrial function relies on the homeostasis and quality control of their proteome, including components of the oxidative phosphorylation (OXPHOS) pathway that generates energy in form of ATP. OXPHOS subunits are under constant exposure to reactive oxygen species due to their oxidation-reduction activities, which consequently make them prone to oxidative damage, misfolding, and aggregation. As a result, quality control mechanisms through turnover and degradation are required for maintaining mitochondrial activity. Degradation of OXPHOS subunits can be achieved through proteomic turnover or modular degradation. In this review, we present multiple protein degradation pathways in plant mitochondria. Specifically, we focus on the intricate turnover of OXPHOS subunits, prior to protein import via cytosolic proteasomal degradation and post import and assembly via intra-mitochondrial proteolysis involving multiple AAA+ proteases. Together, these proteolytic pathways maintain the activity and homeostasis of OXPHOS components.
线粒体的功能依赖于其蛋白质组的动态平衡和质量控制，包括氧化磷酸化（OXPHOS）途径的组成部分，该途径以 ATP 的形式产生能量。由于 OXPHOS 亚基的氧化还原活性，它们会不断受到活性氧的影响，这使得它们容易受到氧化损伤、错误折叠和聚集。因此，需要通过周转和降解等质量控制机制来维持线粒体的活性。OXPHOS 亚基的降解可以通过蛋白质组周转或模块化降解来实现。在这篇综述中，我们介绍了植物线粒体中的多种蛋白质降解途径。具体来说，我们重点介绍了 OXPHOS 亚基在通过胞质蛋白酶体降解进行蛋白质导入之前的复杂周转，以及在导入和组装之后通过涉及多个 AAA+蛋白酶的线粒体内部蛋白水解进行的周转。这些蛋白水解途径共同维持了 OXPHOS 组件的活性和动态平衡。
