Fregien N, Davidson N
Gene. 1986;48(1):1-11. doi: 10.1016/0378-1119(86)90346-x.
We have examined the chicken cytoskeletal actin gene for promoter activity and for the presence of cis-acting gene transcription activating sequences. Plasmids were constructed with the beta-actin promoter or other fragments of the beta-actin gene adjacent to either the truncated Herpes simplex virus (HSK)-tk promoter driving the neo gene or the enhancerless simian virus 40 (SV40) promoter driving the chloramphenicol acetyltransferase (CAT) gene. The neo plasmids were tested for frequency of transformation of mammalian cells to G418 resistance. The CAT constructions were tested for CAT expression in both transient and stable expression systems. We find that the beta-actin promoter is very strong in all of the assay systems and is as strong as any promoter we have tested. Also, we find that there are sequences in the vicinity of the beta-actin promoter which act like an enhancer sequence in activating transcription from the truncated HSV-tk promoter and the enhancerless SV40 promoter. Constructs with these actin sequences augment the transformation frequency of the neo plasmids, and stimulate the level of CAT expression from the CAT plasmids after stable chromosome insertion but not during the transient expression phase.
我们已经检测了鸡细胞骨架肌动蛋白基因的启动子活性以及顺式作用基因转录激活序列的存在情况。构建了一些质粒，其中β-肌动蛋白启动子或β-肌动蛋白基因的其他片段与驱动新霉素基因的截短单纯疱疹病毒（HSV）-tk启动子或驱动氯霉素乙酰转移酶（CAT）基因的无增强子猿猴病毒40（SV40）启动子相邻。检测了新霉素质粒对哺乳动物细胞转化为G418抗性的频率。对CAT构建体在瞬时和稳定表达系统中进行了CAT表达检测。我们发现，β-肌动蛋白启动子在所有检测系统中都非常强，与我们测试过的任何启动子一样强。此外，我们发现在β-肌动蛋白启动子附近存在一些序列，其在激活截短的HSV-tk启动子和无增强子的SV40启动子的转录时，表现得像增强子序列。含有这些肌动蛋白序列的构建体提高了新霉素质粒的转化频率，并在稳定染色体插入后而非瞬时表达阶段刺激了CAT质粒的CAT表达水平。
