Tully D B, Cidlowski J A
Biochem Biophys Res Commun. 1987 Apr 14;144(1):1-10. doi: 10.1016/s0006-291x(87)80467-9.
A computer search of the pBR322 DNA sequence identified five sites matching reported glucocorticoid regulatory element (GRE) DNA consensus sequences and three related sites. A pBR322 DNA fragment containing one GRE site was shown to bind immobilized HeLa S3 cell glucocorticoid receptor and to compete for receptor binding in a competitive binding assay. Conversely, a pBR322 DNA fragment devoid of GRE sites showed barely detectable interaction with glucocorticoid receptor in either of these assays. These results demonstrate the importance of GRE consensus sequences in glucocorticoid receptor interactions with DNA, and further identify a cause for high background binding observed when pBR322 DNA is used as a negative control in studies of glucocorticoid receptor-DNA interactions.
对pBR322 DNA序列进行计算机搜索，发现了五个与报道的糖皮质激素调节元件（GRE）DNA共有序列匹配的位点以及三个相关位点。含有一个GRE位点的pBR322 DNA片段在竞争结合试验中显示能与固定化的HeLa S3细胞糖皮质激素受体结合，并能竞争受体结合。相反，缺乏GRE位点的pBR322 DNA片段在这两种试验中与糖皮质激素受体的相互作用几乎检测不到。这些结果证明了GRE共有序列在糖皮质激素受体与DNA相互作用中的重要性，并进一步确定了在糖皮质激素受体 - DNA相互作用研究中使用pBR322 DNA作为阴性对照时观察到高背景结合的原因。
