Targa F R, de Moura Gallo C V, Huesca M, Scherrer K, Marcaud L
Institut Jacques Monod, Paris, France.
Gene. 1993 Jul 30;129(2):229-37. doi: 10.1016/0378-1119(93)90273-6.
Enhancer activities have been observed in DNA fragments up to 1.36 kb long located on the 3'-side of the cluster of the three alpha-type globin-encoding genes in duck [Kretsovali et al., C.R. Acad. Sci. Paris 307 (1988) 563-568] and chicken [Knezetic and Felsenfeld, Mol. Cell. Biol. 9 (1989) 893-901]. We report here the identification of a chicken silencer element placed upstream from the three GATA-1 sites which constitute the core enhancer element in both species. This silencer element can autonomously reduce the activity of promoters for thymidine kinase and alpha D globin. Band shifts and DNase I footprinting experiments using nuclear extracts from thermosensitive avian erythroblastosis virus-transformed chicken erythroblasts led to the delineation of three sites for DNA-binding proteins within the silencer element.
在鸭[Kretsovali等人，《法国科学院院报》307 (1988) 563 - 568]和鸡[Knezetic和Felsenfeld，《分子细胞生物学》9 (1989) 893 - 901]中，已在位于三个α型珠蛋白编码基因簇3'端长达1.36 kb的DNA片段中观察到增强子活性。我们在此报告鉴定出一个鸡沉默子元件，它位于构成这两个物种核心增强子元件的三个GATA - 1位点的上游。该沉默子元件可自主降低胸苷激酶和αD珠蛋白启动子的活性。使用来自温度敏感型禽成红细胞增多症病毒转化的鸡成红细胞的核提取物进行的凝胶迁移和DNA酶I足迹实验，确定了沉默子元件内DNA结合蛋白的三个位点。
