The human multidrug resistance-associated protein functionally complements the yeast cadmium resistance factor 1.
The human multidrug resistance-associated protein functionally complements the yeast cadmium resistance factor 1.
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人类多药耐药相关蛋白在功能上补充了酵母镉耐药因子 1。
DOI：
10.1073/pnas.93.13.6743
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发表时间：
1996
影响因子：
11.1
通讯作者：
E. Martinoia
中科院分区：
文献类型：
--
作者：
R. Tommasini;R. Evers;E. Vogt;Clotilde Mornet;G. Zaman;A. Schinkel;P. Borst;E. Martinoia
一株酵母耐镉因子(YCF1)基因突变的酿酒酵母菌株(DTY168)对镉敏感。YCF1类似于人类多药耐药相关蛋白MRP(63%的氨基酸相似性)，它通过降低细胞内药物浓度而对各种细胞毒药物产生耐药性。虽然YCF1的作用机制尚不清楚，但最近发现MRP可以跨膜转运谷胱甘肽S结合物。在这里，我们表明，在酵母突变DTY168细胞中表达人MRP基因可以将镉的抗性恢复到野生型水平。在DTY168突变体中，S-(2，4-二硝基苯)-谷胱甘肽在分离的酵母微泡中的转运显著减少，而在表达MRP基因的突变细胞中，这种转运恢复到野生型水平。在细胞分离实验中，我们发现YCF1主要定位于酵母的空泡膜，而MRP在转化的酵母细胞中既与空泡膜有关，也与其他内膜有关。我们的结果表明，酵母YCF1是一个谷胱甘肽S结合泵，与MRP类似，它们提出了酵母对镉的抗性可能涉及镉与谷胱甘肽衍生物的共运输。
A Saccharomyces cerevisiae strain with a disrupted yeast cadmium resistance factor (YCF1) gene (DTY168) is hypersensitive to cadmium. YCF1 resembles the human multidrug resistance-associated protein MRP (63% amino acid similarity), which confers resistance to various cytotoxic drugs by lowering the intracellular drug concentration. Whereas the mechanism of action of YCF1 is not known, MRP was recently found to transport glutathione S-conjugates across membranes. Here we show that expression of the human MRP cDNA in yeast mutant DTY168 cells restores cadmium resistance to the wild-type level. Transport of S-(2,4-dinitrobenzene)-glutathione into isolated yeast microsomal vesicles is strongly reduced in the DTY168 mutant and this transport is restored to wild-type level in mutant cells expressing MRP cDNA. We find in cell fractionation experiments that YCF1 is mainly localized in the vacuolar membrane in yeast, whereas MRP is associated both with the vacuolar membrane and with other internal membranes in the transformed yeast cells. Our results indicate that yeast YCF1 is a glutathione S-conjugate pump, like MRP, and they raise the possibility that the cadmium resistance in yeast involves cotransport of cadmium with glutathione derivatives.