FERRIC REDUCTASE OF SACCHAROMYCES-CEREVISIAE - MOLECULAR CHARACTERIZATION, ROLE IN IRON UPTAKE, AND TRANSCRIPTIONAL CONTROL BY IRON
FERRIC REDUCTASE OF SACCHAROMYCES-CEREVISIAE - MOLECULAR CHARACTERIZATION, ROLE IN IRON UPTAKE, AND TRANSCRIPTIONAL CONTROL BY IRON
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DOI：
10.1073/pnas.89.9.3869
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发表时间：
1992-05-01
影响因子：
11.1
通讯作者：
KLAUSNER, RD
中科院分区：
文献类型：
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作者：
DANCIS, A;ROMAN, DG;KLAUSNER, RD
酿酒酵母的主要铁吸收系统利用作用于细胞外部的三价铁螯合物的还原酶活性。FRE 1基因产物是这种活性所必需的。推导的氨基酸序列的FRE 1蛋白表现出与跨膜结构域相容的疏水区域，并具有显着的相似性，质膜细胞色素b558（X-CGD蛋白），人吞噬细胞氧化还原酶的关键组成部分的序列，这表明FRE 1是酵母铁还原酶的结构组成部分。FRE 1 mRNA水平被铁抑制。融合977碱基对的FRE 1 DNA上游的大肠杆菌lacZ报告基因的翻译起始位点赋予铁依赖性调节β-半乳糖苷酶在酵母中的表达。FRE 1 5'非编码序列的85个碱基对片段含有RAP 1结合位点和重复序列TTTTTGCTCAYC;该片段足以赋予异源下游启动子元件铁抑制转录活性。
The principal iron uptake system of Saccharomyces cerevisiae utilizes a reductase activity that acts on ferric iron chelates external to the cell. The FRE1 gene product is required for this activity. The deduced amino acid sequence of the FRE1 protein exhibits hydrophobic regions compatible with transmembrane domains and has significant similarity to the sequence of the plasma membrane cytochrome b558 (the X-CGD protein), a critical component of a human phagocyte oxidoreductase, suggesting that FRE1 is a structural component of the yeast ferric reductase. FRE1 mRNA levels are repressed by iron. Fusion of 977 base pairs of FRE1 DNA upstream from the translation start site of an Escherichia coli lacZ reporter gene confers iron-dependent regulation on expression of beta-galactosidase in yeast. An 85-base-pair segment of FRE1 5' noncoding sequence contains a RAP1 binding site and a repeated sequence, TTTTTGCTCAYC; this segment is sufficient to confer iron-repressible transcriptional activity on heterologous downstream promoter elements.