Abstract The proteome of the mitochondrial intermembrane space (IMS) contains more than 100 proteins, all of which are synthesized on cytosolic ribosomes and consequently need to be imported by dedicated machineries. The mitochondrial disulfide relay is the major import machinery for soluble proteins in the IMS. Its major component, the oxidoreductase MIA40, interacts with incoming substrates, retains them in the IMS, and oxidatively folds them. After this reaction, MIA40 is reoxidized by the sulfhydryl oxidase augmenter of liver regeneration, which couples disulfide formation by this machinery to the activity of the respiratory chain. In this review, we will discuss the import of IMS proteins with a focus on recent findings showing the diversity of disulfide relay substrates, describing the cytosolic control of this import system and highlighting the physiological relevance of the disulfide relay machinery in higher eukaryotes.

中文翻译：

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高等真核生物中线粒体二硫键中继的蛋白质导入

摘要 线粒体膜间隙 (IMS) 的蛋白质组包含 100 多种蛋白质，所有这些蛋白质都是在胞质核糖体上合成的，因此需要通过专用机器导入。线粒体二硫键中继是 IMS 中可溶性蛋白质的主要进口机制。它的主要成分，氧化还原酶 MIA40，与传入的底物相互作用，将它们保留在 IMS 中，并氧化折叠它们。在这个反应之后，MIA40 被肝脏再生的巯基氧化酶增强剂再氧化，这将这种机制的二硫化物形成与呼吸链的活性结合起来。在这篇综述中，我们将讨论 IMS 蛋白的进口，重点是最近的研究结果显示二硫键中继底物的多样性，