Overlapping Roles of the Cytoplasmic and Mitochondrial Redox Regulatory Systems in the Yeast Saccharomyces cerevisiae
Overlapping Roles of the Cytoplasmic and Mitochondrial Redox Regulatory Systems in the Yeast Saccharomyces cerevisiae
复制标题
酿酒酵母细胞质和线粒体氧化还原调节系统的重叠作用
作者：
Eleanor W. Trotter;C. Grant
摘要硫氧还蛋白是一种高度保守的小氧化还原酶，是维持细胞氧化还原稳态所必需的。酿酒酵母含有细胞质硫氧还蛋白系统（TRX1、TRX2和TRR1）以及完整的线粒体硫氧还蛋白系统，包括硫氧还蛋白（TRX3）和硫氧还蛋白还原酶（TRR2）。在本研究中，我们分析了两个系统之间的功能重叠。通过构建缺失线粒体和细胞质系统（trr1 trr2和trx1 trx2 trx3）的突变株，我们表明细胞可以在这两个系统的情况下生存。细胞质硫氧还蛋白的氧化还原状态的分析表明，它们独立于线粒体系统维持。类似地，对Trx 3的氧化还原状态的分析揭示，它在野生型细胞和缺乏细胞质硫氧还蛋白系统的组分（trx 1、trx 2或trr 1）的突变体中保持还原形式。令人惊讶的是，Trx 3的氧化还原状态也不受线粒体硫氧还蛋白还原酶（trr 2）的损失的影响，并且除非细胞暴露于氧化应激，否则很大程度上维持在还原形式。由于谷胱甘肽还原酶（Glr 1）已被证明是共定位于细胞质和线粒体，我们研究了是否损失的GLR 1影响Trx 3的氧化还原状态。在正常生长条件下，发现TRR2和GLR 1的缺失导致Trx 3的部分氧化，表明Trr 2和Glr 1都需要维持Trx 3的氧化还原状态。在氧化应激或呼吸生长条件下，这种双突变体中Trx3的氧化甚至更明显。总之，这些数据表明Glr 1和Trr 2在线粒体中具有重叠的功能。
ABSTRACT Thioredoxins are small, highly conserved oxidoreductases which are required to maintain the redox homeostasis of the cell. Saccharomyces cerevisiae contains a cytoplasmic thioredoxin system (TRX1, TRX2, and TRR1) as well as a complete mitochondrial thioredoxin system, comprising a thioredoxin (TRX3) and a thioredoxin reductase (TRR2). In the present study we have analyzed the functional overlap between the two systems. By constructing mutant strains with deletions of both the mitochondrial and cytoplasmic systems (trr1 trr2 and trx1 trx2 trx3), we show that cells can survive in the absence of both systems. Analysis of the redox state of the cytoplasmic thioredoxins reveals that they are maintained independently of the mitochondrial system. Similarly, analysis of the redox state of Trx3 reveals that it is maintained in the reduced form in wild-type cells and in mutants lacking components of the cytoplasmic thioredoxin system (trx1 trx2 or trr1). Surprisingly, the redox state of Trx3 is also unaffected by the loss of the mitochondrial thioredoxin reductase (trr2) and is largely maintained in the reduced form unless cells are exposed to an oxidative stress. Since glutathione reductase (Glr1) has been shown to colocalize to the cytoplasm and mitochondria, we examined whether loss of GLR1 influences the redox state of Trx3. During normal growth conditions, deletion of TRR2 and GLR1 was found to result in partial oxidation of Trx3, indicating that both Trr2 and Glr1 are required to maintain the redox state of Trx3. The oxidation of Trx3 in this double mutant is even more pronounced during oxidative stress or respiratory growth conditions. Taken together, these data indicate that Glr1 and Trr2 have an overlapping function in the mitochondria.
硫氧还蛋白的氧化还原依赖性功能对于维持酵母中 DNA 的快速合成是必要的。
DOI：
10.1006/abbi.1995.1240
发表时间：
1995
期刊：
Archives of biochemistry and biophysics.
影响因子：
--
作者：
Muller,EG
通讯作者：
Muller,EG
DOI：
10.1016/s0021-9258(18)31570-9
发表时间：
1991-05
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Eric G D Muller
通讯作者：
Eric G D Muller
影响因子：
3.3
作者：
E. Muller
通讯作者：
E. Muller