Characterization of the human protease nexin-1 promoter and its regulation by Sp1 through a G/C-rich activation domain.
Characterization of the human protease nexin-1 promoter and its regulation by Sp1 through a G/C-rich activation domain.
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人蛋白酶 nexin-1 启动子的表征及其通过富含 G/C 的激活结构域受到 Sp1 的调节。
DOI：
10.1046/j.1471-4159.1996.67020498.x
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发表时间：
1996
影响因子：
4.7
通讯作者：
Cunningham,DD
中科院分区：
文献类型：
--
作者：
Guttridge,DC;Cunningham,DD
蛋白酶连接蛋白-1（PN-1）是细胞外环境中丝氨酸蛋白酶的有效抑制剂。它在神经系统中大量表达，被认为参与局部损伤和修复过程。虽然已经获得了一些关于PN-1基因结构的信息，但对调节其表达的thecis和trans-acting因子知之甚少。这些因素的阐明应能更好地理解PN-1在发育和伤口修复过程中的功能。在这份报告中，我们描述了人PN-1启动子的特性，并确定了调控结构域和介导其转录活性的反式激活因子。该启动子在转录起始位点附近是高度G/C富集的。它表现出组织特异性，并由-480位上游的沉默元件负调控。一个正调控元件被定位在−199和−45之间，其中包含多个推定的Sp1共有结合位点。电泳迁移率变动分析证实Sp1特异性结合PN-1启动子的该区域。DNA酶I足迹分析显示，在−103和−56之间有6个潜在的Sp1结合位点，这些位点受到重组Sp1的保护。对Sp1缺陷型果蝇SL 2细胞系的共转染实验也表明，Sp1以剂量依赖性方式激活PN-1启动子活性。因此，我们的分析表明，PN-1转录的激活是由Sp1通过5′近端启动子区富含G/C的顺式作用元件调节的。
Protease nexin‐1 (PN‐1) is a potent inhibitor of serine proteases in the extracellular environment. It is abundantly expressed in the nervous system, where it is thought to participate in local injury and repair processes. Although some information has been obtained regarding PN‐1 gene structure, relatively little is known about thecis‐ andtrans‐acting factors that regulate its expression. Elucidation of these factors should provide a better understanding of PN‐1 function during development and wound repair. In this report we describe the characterization of the human PN‐1 promoter and identify regulatory domains and a transactivator mediating its transcriptional activity. The promoter is highly G/C rich proximal to the transcriptional start site. It exhibits tissue specificity and is negatively regulated by a silencer element upstream of position −480. A positive regulatory element was mapped between −199 and −45, which contains multiple putative Sp1 consensus binding sites. Electrophoretic mobility shift analysis confirmed that Sp1 specifically binds this region of the PN‐1 promoter. DNase I foot‐printing revealed six potential Sp1 binding sites between −103 and −56 that were protected by recombinant Sp1. Cotransfection experiments into the Sp1‐deficientDrosophilaSL2 cell line also showed that Sp1 activates PN‐1 promoter activity in a dose‐dependent fashion. Thus, our analysis demonstrates that activation of PN‐1 transcription is regulated by Sp1 through G/C‐richcis‐acting elements in the 5′ proximal promoter region.