Ravazzolo R, Karsenty G, de Crombrugghe B
Department of Molecular Genetics, University of Texas, M. D. Anderson Cancer Center, Houston 77030.
J Biol Chem. 1991 Apr 25;266(12):7382-7.
We have identified, in nuclear extracts of NIH-3T3 fibroblasts, a factor which binds a sequence between -339 and -361 in the mouse alpha 1(I) collagen promoter. A 3-base pair substitution mutation introduced in this promoter element, which abolishes the binding of the factor, increases the activity of the promoter 4-fold in DNA transfection experiments. This suggests that this element is a negative regulator of transcription. The factor which binds to the -339 to -361 sequence is present in type I collagen-producing cell lines but not in a variety of other cell types, suggesting that it is involved in the tissue-specific regulation of the alpha 1(I) gene.
我们在NIH-3T3成纤维细胞的核提取物中鉴定出一种因子，它能结合小鼠α1（I）型胶原启动子中-339至-361之间的序列。在该启动子元件中引入的一个3碱基对替换突变消除了该因子的结合，在DNA转染实验中，该启动子的活性增加了4倍。这表明该元件是转录的负调节因子。与-339至-361序列结合的因子存在于产生I型胶原的细胞系中，但不存在于多种其他细胞类型中，这表明它参与了α1（I）基因的组织特异性调控。
