Protein disulfide isomerase acts as a redox-dependent chaperone to unfold cholera toxin
Protein disulfide isomerase acts as a redox-dependent chaperone to unfold cholera toxin
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DOI：
10.1016/s0092-8674(01)00289-6
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发表时间：
2001-03-23
期刊：
影响因子：
64.5
通讯作者：
Rapoport, TA
中科院分区：
文献类型：
--
作者：
Tsai, B;Rodighiero, C;Rapoport, TA
霍乱毒素由霍乱弧菌周质中的两个亚单位组装而成，并在靶细胞的类似区室（内质网（ER）的腔）中分解，然后其片段（Al链）被转运到胞质溶胶中。我们发现，蛋白质二硫键异构酶（PDI）在ER腔功能拆卸和展开毒素，一旦其A链已被切割。PDI作为一个氧化还原驱动的伴侣，在还原状态下，它结合到A链，并在氧化状态下，它释放it.Our的结果解释了霍乱毒素的途径，建议PDI在逆行蛋白质运输到胞质溶胶中的作用，并表明PDI可以作为一种新型的伴侣，其结合和释放的底物是由氧化还原，而不是ATP酶，周期调节。
Cholera toxin is assembled from two subunits in the periplasm of Vibrio cholerae and disassembled in the analogous compartment of target cells, the lumen of the endoplasmic reticulum (ER), before a fragment of it, the Al chain, is transported into the cytosol. We show that protein disulfide isomerase (PDI) in the ER lumen functions to disassemble and unfold the toxin once its A chain has been cleaved. PDI acts as a redox-driven chaperone; in the reduced state, it binds to the A chain and in the oxidized state it releases it. Our results explain the pathway of cholera toxin, suggest a role for PDI in retrograde protein transport into the cytosol, and indicate that PDI can act as a novel type of chaperone, whose binding and release of substrates is regulated by a redox, rather than an ATPase, cycle.