Functional reconstitution of mitochondrial Fe/S cluster synthesis on Isu1 reveals the involvement of ferredoxin
Functional reconstitution of mitochondrial Fe/S cluster synthesis on Isu1 reveals the involvement of ferredoxin
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DOI：
10.1038/ncomms6013
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发表时间：
2014-10
影响因子：
16.6
通讯作者：
H. Webert;S. Freibert;A. Gallo;Torsten Heidenreich;U. Linne;Stefan Amlacher;E. Hurt;U. Mühlenhoff;L. Banci;R. Lill
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文献类型：
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作者：
H. Webert;S. Freibert;A. Gallo;Torsten Heidenreich;U. Linne;Stefan Amlacher;E. Hurt;U. Mühlenhoff;L. Banci;R. Lill
铁硫蛋白（Fe/S）的成熟涉及复杂的生物合成机制，在线粒体支架蛋白Isu 1上[2Fe-2S]簇的体内合成需要半胱氨酸蛋白酶复合物Nfs 1-Isd 11、共济失调蛋白（frataxin）、铁氧还蛋白Yah 1及其还原酶Arh 1。Yah 1-Arh 1的作用仍然是个谜，因为它们在体外Fe/S簇组装中并不需要。在这里，我们重建[2Fe-2S]簇在Isu 1上的合成反应依赖于Nfs 1-Isd 11，共济失调蛋白，Yah 1，Arh 1和NADPH。与细菌系统不同，frataxin是Fe/S簇生物合成的重要组成部分，并且与Yah 1同时且化学计量地需要。还原而非氧化的Yah 1与apo-Isu 1紧密相互作用，表明Yah 1-apo-Isu 1之间的动态相互作用。核磁共振结构的研究确定了Yah 1-apo-Isu 1相互作用的表面，并提出了一个途径，电子流从减少铁氧还蛋白Isu 1。总之，我们的研究定义了铁氧还蛋白Yah 1及其人类直系同源物FDX 2在线粒体Fe/S簇合成中的分子功能。
Maturation of iron–sulphur (Fe/S) proteins involves complex biosynthetic machinery.In vivosynthesis of [2Fe–2S] clusters on the mitochondrial scaffold protein Isu1 requires the cysteine desulphurase complex Nfs1-Isd11, frataxin, ferredoxin Yah1 and its reductase Arh1. The roles of Yah1–Arh1 have remained enigmatic, because they are not required forin vitroFe/S cluster assembly. Here, we reconstitute [2Fe–2S] cluster synthesis on Isu1 in a reaction depending on Nfs1-Isd11, frataxin, Yah1, Arh1 and NADPH. Unlike in the bacterial system, frataxin is an essential part of Fe/S cluster biosynthesis and is required simultaneously and stoichiometrically to Yah1. Reduced but not oxidized Yah1 tightly interacts with apo-Isu1 indicating a dynamic interaction between Yah1–apo-Isu1. Nuclear magnetic resonance structural studies identify the Yah1–apo-Isu1 interaction surface and suggest a pathway for electron flow from reduced ferredoxin to Isu1. Together, our study defines the molecular function of the ferredoxin Yah1 and its human orthologue FDX2 in mitochondrial Fe/S cluster synthesis.