Transcriptional activation of the Drosophila melanogaster glucose-6- phosphate dehydrogenase gene by insertion of defective P elements

串联插入缺陷P元件(1.15kb KP和0.6kb核心P)加快了果蝇葡萄糖-6-磷酸脱氢酶(G6PD)基因的转录速度。在本研究中，我们通过体外转录和凝胶抑制实验分析了G6PD启动子的激活机制。结果表明，G6PD启动子激活与核心P区的顺式作用区域和Kp中的两个顺式作用区域有关，广州S胚核提取液中存在与每个顺式作用区域特异结合的转录调控蛋白(S)。另一方面，P元件并不激活正常的肌动蛋白5C启动子，而是当G6PD转录起始点周围的20bp序列放在启动子前面时激活启动子。这似乎是激活所需的20bp序列中的GC富集区。

Tandem insertions of defective P elements (1.15 kb KP and 0.6 kb core P) accelerate the transcription rate of the glucose-6-phosphate dehydrogenase (G6PD) gene in Drosophila melanogaster. In this resarch, we have analyzed the activation mechanism of G6PD promoter by in vitro transcription and gel retardation assays. Results showed that on cis-acting region in the core P and two such regions in the KP are associated with the activation of G6PD promoter, and that putative transcriptional regulatory protein(s) which specifically bind to each of the cis-acting regions are present in nuclear extracts of Canton S embryos. On the other hand, the P elements do not activate the normal actin 5C promoter, but activate the promoter when the 20 bp sequence around the G6PD transcription start site is placed in front of the promoter. It seems that the GC-rich region in the 20 bp sequence is required for the activation.