Manipulation of oxidative protein folding and PDI redox state in mammalian cells
Manipulation of oxidative protein folding and PDI redox state in mammalian cells
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DOI：
10.1093/emboj/20.22.6288
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发表时间：
2001-11-15
期刊：
影响因子：
11.4
通讯作者：
Sitia, R
中科院分区：
文献类型：
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作者：
Mezghrani, A;Fassio, A;Sitia, R
在内质网(ER)中，二硫键同时在新生蛋白质中形成，并从错误折叠或组装的分子中移除。因此，在这个隔间中，氧化还原状态必须受到精确的调节。在这里，我们发现人类雌激素受体1-Lα和雌激素受体1-Lβ(HEROS)都通过选择性地氧化PDI促进免疫球蛋白亚基中二硫键的形成。二硫键的形成由HEROS控制，HEROS站在电子流的关键点上，从新生的分泌蛋白质开始，通过PDI。ERp57是另一种内质网驻留的氧化还原酶，其氧化还原状态不受ER1-Lα过表达的影响，这表明平行和特定的途径控制着内质网中的氧化蛋白折叠。Ero1-LαCXXCXXC基序中的突变体通过限制免疫球蛋白的氧化起到显性负性作用。因此，活细胞中依赖PDI的氧化折叠可以通过使用HERO变体来操纵。
In the endoplasmic reticulum (ER), disulfide bonds are simultaneously formed in nascent proteins and removed from incorrectly folded or assembled molecules. In this compartment, the redox state must be, therefore, precisely regulated. Here we show that both human Ero1-L alpha and Ero1-L beta (hEROs) facilitate disulfide bond formation in immunoglobulin subunits by selectively oxidizing PDI. Disulfide bond formation is controlled by hEROs, which stand at a crucial point of an electron-flow starting from nascent secretory proteins and passing through PDI. The redox state of ERp57, another ER-resident oxidoreductase, is not affected by over-expression of Ero1-L alpha, suggesting that parallel and specific pathways control oxidative protein folding in the ER. Mutants in the Ero1-L alpha CXXCXXC motif act as dominant negatives by limiting immunoglobulin oxidation. PDI-dependent oxidative folding in living cells can thus be manipulated by using hERO variants.