Intracellular catalysis of disulfide bond formation by the human sulfhydryl oxidase, QSOX1
Intracellular catalysis of disulfide bond formation by the human sulfhydryl oxidase, QSOX1
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DOI：
10.1042/bj20061510
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发表时间：
2007-06-15
影响因子：
4.1
通讯作者：
Bulleid, Neil J.
中科院分区：
文献类型：
--
作者：
Chakravarthi, Seerna;Jessop, Catherine E.;Bulleid, Neil J.
黄蛋白氧化酶Erv2p的发现为酵母中二硫键的形成提供了氧化电位，这导致了对该蛋白的哺乳动物同源物作用的研究。Erv2p的哺乳动物同源物包括来自人肺成纤维细胞、豚鼠子宫内膜细胞和大鼠精囊的QSOX（巯基氧化酶）。在目前的研究中，我们发现，当在哺乳动物细胞中表达时，人类QSOX1蛋白的长版本（hQSOX1 a）是一种主要定位于高尔基体的跨膜蛋白。我们也提出了第一个证据表明hQSOX1 a可以作为氧化酶在体内发挥作用。通过对分泌蛋白羧肽酶Y的折叠分析，hQSOX1 a的过表达抑制了酵母中er1（内质网氧化酶1）完全缺失的致命性，并恢复了二硫键的形成。
The discovery that the flavoprotein oxidase, Erv2p, provides oxidizing potential for disulfide bond formation in yeast, has led to investigations into the roles of the mammalian homologues of this protein. Mammalian homologues of Erv2p include QSOX (sulfhydryl oxidases) from human lung fibroblasts, guinea-pig endometrial cells and rat seminal vesicles. In the present study we show that, when expressed in mammalian cells, the longer version of human QSOX1 protein (hQSOX1 a) is a transmembrane protein localized primarily to the Golgi apparatus. We also present the first evidence showing that hQSOX1 a can act in vivo as an oxidase. Overexpression of hQSOX1 a suppresses the lethality of a complete deletion of ERO1 (endoplasmic reticulum oxidase 1) in yeast and restores disulfide bond formation, as assayed by the folding of the secretory protein carboxypeptidase Y.