Webster N J, Kong Y, Cameron K E, Resnik J L
Department of Medicine, University of California, San Diego, La Jolla 92093-0673.
Diabetes. 1994 Feb;43(2):305-12. doi: 10.2337/diab.43.2.305.
We have shown previously that a 500-bp region of the human insulin receptor promoter (-0.3 to -1.8 kb) was able to stimulate transcription from a heterologous thymidine kinase promoter in HepG2 hepatoma cells but not in HeLa fibroblasts. Footprint analysis localized the transcription factor binding sites to a 36-bp region at -1420. In this paper, we analyze the factors that recognize this element and show that it contains binding sites for the CAAT/enhancer binding protein C/EBP and nuclear factor 1 (NF-1). In addition we show that both C/EBP alpha and the C/EBP beta can transactivate the human insulin receptor promoter in a dose-dependent manner.
我们之前已经表明，人类胰岛素受体启动子的一个500碱基对区域（-0.3至-1.8 kb）能够刺激HepG2肝癌细胞中异源胸苷激酶启动子的转录，但在HeLa成纤维细胞中则不能。足迹分析将转录因子结合位点定位到-1420处的一个36碱基对区域。在本文中，我们分析了识别该元件的因子，并表明它包含CCAAT/增强子结合蛋白C/EBP和核因子1（NF-1）的结合位点。此外，我们还表明C/EBPα和C/EBPβ都能以剂量依赖的方式反式激活人类胰岛素受体启动子。
