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人体ε－珠蛋白基因５′旁侧ＤＮＡ序列对该基因时空表达与调控起着十分重要的作用。本文运用凝胶电泳阻抑法，ＤＮａｓｅＩ足印法和Ｓｏｕｔｈｗｅｓｔｅｒｎｂｌｏｔ分析法发现在胚胎型红白血病细胞株Ｋ５６２细胞中有一个特异的核蛋白因子（简称ε－ＳＳＰ，其分子量大约为８０ｋＤ），它能专一地与人体ε－珠蛋白基因５′旁侧一个红细胞专一和发育时期特异的正调控元件（ε－ＰＲＥＩＩ，－４４６ｂｐ到－４１９ｂｐ）相结合。竞争实验表明该因子与ε－ＰＲＥＩＩ的结合能被人体ε－珠蛋白基因启动子区ＤＮＡ片段（－１７７ｂｐ到＋１ｂｐ）所竞争；同时也能被人体β－类珠蛋白基因远侧端调控元件ＬＣＲ中的ＤＮａｓｅＩ超敏感点Ｉ核心区ＤＮＡ片段（－１０９６５ｂｐ到－１０６８１ｂｐ）与超敏感点ＩＩ核心区ＤＮＡ片段（－１４９９３ｂｐ到－１４７１８ｂｐ）所竞争。我们的结果提示了ε－ＳＳＰ不仅是一个与红细胞专一性和发育时期特异性相关的反式调控因子，而且它可能介导远侧端调控元件（ＬＣＲ）与近侧端调控元件启动子之间的相互作用，共同调节ε－珠蛋白基因在胚胎期的表达。
The DNA sequence flanking the 5 ’side of human ε-globin gene plays a very important role in the spatiotemporal expression and regulation of this gene. In this paper, using gel electrophoresis inhibition method, DNaseI footprinting method and Southwestern blot analysis found that in embryonic erythroleukemia cell line K562 cells have a specific nuclear protein factor (ε-SSP, the molecular weight of about 80kD), it can Specifically binds to a single erythrocyte-specific and developmentally-specific positive regulatory element (ε-PREII, -446 bp to -419 bp) flanking the 5 ’of human ε-globin gene. Competition experiments showed that the binding of ε-PREII and ε-globin gene was competitive with the DNA fragment (-177bp to + 1bp) in human ε-globin gene promoter region, and also could be regulated by LCR (-10965bp to -10681bp) in DNase I hypersensitive point I core region competed with the DNA fragment of hypersensitive point II core region (-14993bp to -14718bp). Our results suggest that ε-SSP is not only a trans regulatory factor that is specific for erythrocyte specificity and developmental stage, but it may also mediate the expression of distal regulatory elements (LCRs) and proximal regulatory elements The interaction between the regulation of ε-globin gene expression in embryonic stage.