Tissue-specific regulatory elements in the human alcohol dehydrogenase 6 gene.
Tissue-specific regulatory elements in the human alcohol dehydrogenase 6 gene.
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人类乙醇脱氢酶 6 基因中的组织特异性调控元件。
DOI：
10.1089/10445490050128412
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Edenberg,HJ
中科院分区：
文献类型：
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作者：
Zhi,X;Chan,EM;Edenberg,HJ
人类乙醇脱氢酶基因ADH 6在胎儿和成人肝脏中表达水平最高。我们绘制了影响其表达的顺式作用元件。bp-34的序列 至-62（位点C），包括TATA盒，被来自肝脏、肝细胞瘤细胞和成纤维细胞的核蛋白强烈结合。一种去除C位点上游部分但保留TATA同源性的截短 完整的显著降低转录;改变该区域中的5 bp具有小得多的影响。C位点的一部分可被C/EBPα结合，但与C/EBPα或C/EBPβ共转染后， 转录。近端区域没有表现出组织特异性，因此我们克隆了上游区域来寻找额外的调节序列。在-1.6和-2.3kb之间的区域刺激转录 在肝癌细胞中，并在成纤维细胞中抑制它。我们在这个区域确定了两个位点，它们独立于方向影响转录。位点1是成纤维细胞的负调控元件 但对肝癌细胞无影响。位点2在肝癌细胞中是一个正调控元件，但在成纤维细胞中没有作用。这种积极和消极调节因素的结合可以发挥 在ADH 6的组织特异性表达中起重要作用。
The human alcohol dehydrogenase geneADH6is expressed at the highest levels in fetal and adult liver. We have mappedcis-acting elements that affect its expression. The sequence from bp -34 to -62 (site C) that includes the TATA box was strongly bound by nuclear proteins from liver, hepatoma cells, and fibroblasts. A truncation that removed the upstream part of site C but left the TATA homology intact dramatically reduced transcription; altering 5 bp in this region had much less effect. Part of site C can be bound by C/EBPα, but cotransfection with C/EBPα or C/EBPβ did not stimulate transcription. The proximal region did not display tissue specificity, so we cloned the upstream region to search for additional regulatory sequences. The region between -1.6 and -2.3 kb stimulated transcription in hepatoma cells and inhibited it in fibroblasts. We identified two sites in this region that affect transcription independently of their orientation. Site 1 was a negative regulatory element in fibroblasts but had no effect in hepatoma cells. Site 2 was a positive regulatory element in hepatoma cells but had no effect in fibroblasts. This combination of positive and negative regulatory elements can play a significant role in the tissue-specific expression ofADH6.