Atchison M L, Perry R P
Cell. 1986 Jul 18;46(2):253-62. doi: 10.1016/0092-8674(86)90742-7.
Transcription of immunoglobulin kappa genes is regulated by enhancer and promoter elements, both of which function in a tissue-specific fashion. We have studied the interaction of these elements by transfecting plasmacytoma cells with genes that have tandem kappa promoters located next to a single kappa enhancer and assaying these genes for transient or stable transcription. We find that the promoters located proximal and distal to the enhancer function identically whether they are separated by 440 bp or by 2.7 kb or whether they are located 1.7 or 7.7 kb away from the enhancer. Our results indicate that the immunoglobulin kappa enhancer does not operate as a bidirectional entry site for RNA polymerase or for other factors associated with the transcription complex. Rather, they suggest that the enhancer exerts its influence uniformly over large distances and independently of the presence of intervening promoters.
免疫球蛋白κ基因的转录受增强子和启动子元件调控，二者均以组织特异性方式发挥作用。我们通过用含有串联κ启动子且紧邻单个κ增强子的基因转染浆细胞瘤细胞，并检测这些基因的瞬时或稳定转录，来研究这些元件之间的相互作用。我们发现，位于增强子近端和远端的启动子，无论它们被440 bp还是2.7 kb隔开，也无论它们距离增强子1.7 kb还是7.7 kb，其功能都是相同的。我们的结果表明，免疫球蛋白κ增强子并非作为RNA聚合酶或与转录复合物相关的其他因子的双向进入位点发挥作用。相反，结果提示增强子在远距离上均匀发挥其影响，且不受中间启动子存在与否的影响。
