Hirano T, Iwakura Y
Institute of Medical Science, University of Tokyo, Japan.
Biochimie. 1990 May;72(5):327-36. doi: 10.1016/0300-9084(90)90028-f.
By using gel mobility shift assay, it was shown that the nuclear extract from F9 embryonal carcinoma (EC) cells contains a novel transcriptional regulatory factor, BF-H, that binds to the 5' upstream region of the early gene of polyoma virus. Two binding sites were located in the transcriptional enhancer domain "A" (nucleotide 5034-5041) and in the 5' upstream of the domain "A" (4998-5005), having a consensus motif (AAPuATGG) between them. Combination of in vitro mutagenesis with chloramphenicol acetyltransferase (CAT) assay revealed that BF-H is a positive transcriptional factor. Interestingly, the binding of BF-H disappeared after differentiation of F9 cells by treatment with retinoic acid, whereas BF-H was present in the F9 cells differentiated with both retinoic acid and dibutyryl cyclic AMP (dbcAMP). These observations suggest that BF-H regulates the expression of genes in a developmental stage-specific manner in early embryos of the mouse.
通过凝胶迁移率变动分析表明，F9胚胎癌细胞的核提取物含有一种新型转录调节因子BF-H，它能与多瘤病毒早期基因的5'上游区域结合。两个结合位点分别位于转录增强子结构域“A”（核苷酸5034 - 5041）以及结构域“A”的5'上游（4998 - 5005），二者之间具有共有基序（AAPuATGG）。体外诱变与氯霉素乙酰转移酶（CAT）分析相结合表明BF-H是一种正向转录因子。有趣的是，在用视黄酸处理使F9细胞分化后，BF-H的结合消失，而在用视黄酸和二丁酰环磷腺苷（dbcAMP）分化的F9细胞中BF-H仍然存在。这些观察结果表明，BF-H以发育阶段特异性的方式调节小鼠早期胚胎中基因的表达。
