Stalder J
Abteilung für Zell- und Entwicklungsbiologie, Universität Bern, Switzerland.
Nucleic Acids Res. 1988 Dec 9;16(23):11027-45. doi: 10.1093/nar/16.23.11027.
Insertion of 1.5 kb of the 5' flanking region of the adult alpha-globin gene of X. laevis in front of the CAT structural gene promotes synthesis of CAT in transiently transfected X. laevis kidney cells. Fusion of transiently transfected kidney cells with erythroblasts isolated from anaemic frogs stimulates CAT expression 3-4 fold in the resulting transient heterokaryons. The stimulation is specific for the alpha-globin promoter and is obtained after fusion with erythroid cells but not with hepatocytes or kidney cells. Stably transfected kidney cells express drastically reduced CAT activity as compared with transiently transfected cells. Nevertheless, fusion of stably transfected kidney cells with erythroblasts leads to a 10-17 fold stimulation of CAT expression. The experiments suggest that erythroid specific transacting factors stimulate expression of CAT controlled by the adult alpha-globin promoter.
将非洲爪蟾成年α-珠蛋白基因5'侧翼区的1.5 kb片段插入到CAT结构基因之前，可促进其在瞬时转染的非洲爪蟾肾细胞中合成CAT。将瞬时转染的肾细胞与从贫血青蛙中分离出的成红细胞融合，可使所得瞬时异核体中的CAT表达提高3 - 4倍。这种刺激对α-珠蛋白启动子具有特异性，并且是在与红细胞融合后获得的，而与肝细胞或肾细胞融合则不会出现这种情况。与瞬时转染的细胞相比，稳定转染的肾细胞表达的CAT活性大幅降低。然而，将稳定转染的肾细胞与成红细胞融合会导致CAT表达受到10 - 17倍的刺激。这些实验表明，红细胞特异性反式作用因子可刺激由成年α-珠蛋白启动子控制的CAT表达。
