Pi class glutathione S-transferase genes are regulated by Nrf2 through an evolutionarily conserved regulatory element in zebrafish
Pi class glutathione S-transferase genes are regulated by Nrf2 through an evolutionarily conserved regulatory element in zebrafish
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DOI：
10.1042/bj20041860
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发表时间：
2005-05-15
影响因子：
4.1
通讯作者：
Yamamoto, M
中科院分区：
文献类型：
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作者：
Suzuki, T;Takagi, Y;Yamamoto, M
Pi 类 GST（谷胱甘肽 S 转移酶）是脊椎动物 GST 蛋白家族的成员，可催化 GSH 与亲电化合物的结合。 Pi 类 GST 基因的表达可以通过暴露于亲电子试剂来诱导。我们之前证明转录因子 Nrf2（NF-E2 p45 相关因子 2）不仅在哺乳动物中介导这种诱导，而且在鱼类中也是如此。在本研究中，我们分离出了含有基因 gstp1 和 gstp2 的斑马鱼基因组区域。斑马鱼 gstp1 和 gstp2 的调控区域已通过 GFP（绿色荧光蛋白）报告基因分析通过显微注射到斑马鱼胚胎中进行了检查。 gstp1 启动子的缺失和点突变分析表明，ARE（抗氧化反应元件）样序列位于转录起始位点上游 50 bp，这对于 Nrf2 反式激活至关重要。使用 EMSA（电泳迁移率变动测定）分析，我们表明斑马鱼 Nrf2-MafK 异二聚体特异性结合到该序列。所有脊椎动物 Pi 类 GST 基因在其启动子区域都具有相似的 ARE 样序列。我们认为该序列是 Pi 类 GST 基因中 Nrf2 的保守靶位点。
Pi class GSTs (glutathione S-transferases) are a member of the vertebrate GST family of proteins that catalyse the conjugation of GSH to electrophilic compounds. The expression of Pi class GST genes can be induced by exposure to electrophiles. We demonstrated previously that the transcription factor Nrf2 (NF-E2 p45-related factor 2) mediates this induction, not only in mammals, but also in fish. In the present study, we have isolated the genomic region of zebrafish containing the genes gstp1 and gstp2. The regulatory regions of zebrafish gstp1 and gstp2 have been examined by GFP (green fluorescent protein) -reporter gene analyses using microinjection into zebrafish embryos. Deletion and point-mutation analyses of the gstp1 promoter showed that an ARE (antioxidant-responsive element)-like sequence is located 50 bp upstream of the transcription initiation site which is essential for Nrf2 trans activation. Using EMSA (electrophoretic mobility-shift assay) analysis we showed that zebrafish Nrf2-MafK heterodimer specifically bound to this sequence. All the vertebrate Pi class GST genes harbour a similar ARE-like sequence in their promoter regions. We propose that this sequence is a conserved target site for Nrf2 in the Pi class GST genes.