红系造血分化中分化调节因子的表达及调控

摘要

Objective To investigate the expression of erythroid differentiation regulate factor (EDRF) in normal he-matopoitic tissue and erythroleukemia cells, and to explore the mechanism of EDRF regulation. Methods The expression of EDRF in erytholeukemia cell NF-E2, HB22.2 and in mice fetus liver tissue was detected by Northern blot method, the DNA transmutation was detected by Southern blot method. The gradual change of EDRF expression during erythoid differentiation was observed by using erythroleukemia cell HB60-5 which induced differentiation by changing culture. To observe the effects of erythroid factors GATA-1, NF-E2 and Fli-1 on EDRF expression by using transgenic technique. Results The transfection of NF-E2 into CB3 and HB22.2 could restore the expression of EDRF. During the erythroid differentiation of HB60-5 cell, the NF-2, GATA-1, α-globin and EDRF expression were gradually evaluated simultaneously. In HB60-5 cell, transfection of GATA-1 could promote the expression of EDRF, in contrast, the transfection of Fli-1 suppressed the expression of EDRF. Conclusions EDRF was erythroid specific gene which was high expressed in normal erythroid tissue , however in erythroleukemia cells the high expression of EDRF was greatly suppressed which was not caused by DNA aberration. EDRF could be up-regulated by erythroid factor GATA-1 and NF-E2, and down-regulated by Fli-1.%目的 探讨红系分化调节因子(EDRF)在红白血病及正常造血组织中的表达差异及可能的调控机制.方法 应用Northern blot方法检测红白血病细胞HB22.2、CB3中EDRF基因的表达,并以正常小鼠胚胎肝脏组织作为对照；通过改变培养条件,诱导红白血病细胞系HB60-5成熟分化,探讨红系分化中EDRF表达的变化；采用Southern blot 方法 对EDRF基因进行DNA水平检测；通过转基因的方法探讨红系造血调控因子GATA-1、NF-E2、Fli-1对EDRF表达的影响.结果 在胚胎肝组织中EDRF表达水平较高,在NF-E2缺陷的红白血病细胞株HB22.2及CB3中,EDRF表达降低,同时α-珠蛋白表达缺失；Southern blot检测未发现红白血病细胞与正常胚胎肝脏组织EDRF基因的差别；HB22.2及CB3转染NF-E2基因后,血红蛋白及EDRF表达水平均明显上调；诱导HB60-5分化成熟后,NF-E2、GATA-1、α-珠蛋白及EDRF的表达逐渐增高,具有一定的相关性；HB60-5细胞转染GATA-1基因后可明显上调EDRF表达,转染Fli-1基因后则EDRF表达水平下降.结论 EDRF是红系造血相关基因,在正常红系细胞中具有高水平表达；红白血病细胞系中EDRF的表达受抑,这种表达减低不是DNA突变所致；红系造血因子GATA-1、NF-E2可上调EDRF的表达,Fli-1可下调EDRF表达.