Pruzina S, Antoniou M, Hurst J, Grosveld F, Philipsen S
National Institute for Medical Research, London, UK.
Biochim Biophys Acta. 1994 Oct 18;1219(2):351-60. doi: 10.1016/0167-4781(94)90059-0.
In this paper we describe a complete deletional analysis of hypersensitive site three (HS3) of the human beta-globin Locus Control Region (LCR). The previously defined core fragment consists of 6 footprinted regions, with multiple binding sites for the erythroid-specific factor GATA-1 and G-rich motifs that can interact with ubiquitous factors such as Sp1 and TEF-2. We show in this paper that the 5' half of this fragment is the most important for activity in murine erythroleukemia (MEL) cells. A fragment containing footprints 1-4 can stimulate transcription of a linked human beta-globin gene to levels of about 40% of that obtained with footprints 1-6. Constructs containing either footprints 1-3 or 3-6 cannot be distinguished from the beta-globin gene alone. We further show that binding sites for the erythroid-specific factor NF-E2 can co-operatively interact with parts of the HS3 core fragment, and that HS3 requires elements upstream from -103 in the human beta-globin promoter for full activity. The importance of these results is discussed in the context of the regulation of the genes in the human beta-globin cluster.
在本文中，我们描述了对人类β-珠蛋白基因座控制区（LCR）超敏位点三（HS3）的完整缺失分析。先前定义的核心片段由6个足迹区域组成，具有多个红细胞特异性因子GATA-1的结合位点以及可与诸如Sp1和TEF-2等普遍存在的因子相互作用的富含G的基序。我们在本文中表明，该片段的5'半部分对鼠红细胞白血病（MEL）细胞中的活性最为重要。包含足迹1-4的片段可将相连的人类β-珠蛋白基因的转录刺激至约为足迹1-6所获得水平的40%。包含足迹1-3或3-6的构建体与单独的β-珠蛋白基因无法区分。我们进一步表明，红细胞特异性因子NF-E2的结合位点可与HS3核心片段的部分协同相互作用，并且HS3需要人类β-珠蛋白启动子中-103上游的元件才能实现完全活性。在人类β-珠蛋白基因簇中基因调控的背景下讨论了这些结果的重要性。
