2 DISTINCT TRANSCRIPTION FACTORS BIND TO THE HSV THYMIDINE KINASE PROMOTER INVITRO
2 DISTINCT TRANSCRIPTION FACTORS BIND TO THE HSV THYMIDINE KINASE PROMOTER INVITRO
复制标题
DOI：
10.1016/0092-8674(85)90113-8
复制
发表时间：
1985-01-01
期刊：
影响因子：
64.5
通讯作者：
TJIAN, R
中科院分区：
文献类型：
--
作者：
JONES, KA;YAMAMOTO, KR;TJIAN, R
我们的特点是在体外转录系统来自未感染的HeLa细胞，准确地启动RNA合成的疱疹病毒胸苷激酶（TK）启动子。分析的链接扫描，单网站，启动子倒置突变体显示，TK上游元素以前在体内映射在体外准确识别。在重建实验中TK转录所需的蛋白质组分被发现含有多种特异性结合TK启动子的蛋白质种类。用野生型和突变型启动子进行的DNA酶I足迹实验表明，TK上游元件含有三个独特的蛋白结合位点，其中两个似乎被Sp1转录因子识别，一个与结合到“CCAAT”序列的细胞蛋白相互作用。胸苷激酶基因的最佳表达似乎需要这两种类型的转录因子与启动子的三个上游元件的协调相互作用。
We have characterized an in vitro transcription system derived from uninfected HeLa cells that accurately initiates RNA synthesis at the herpes virus thymidine kinase (TK) promoter. Analysis of linker-scanning, single-site, and promoter-inversion mutants reveals that the TK upstream elements previously mapped in vivo are accurately recognized in vitro. A protein fraction required for TK transcription in reconstitution experiments was found to contain multiple protein species that bind specifically to the TK promoter. DNAase I footprint experiments with wild-type and mutant promoters reveal that the TK upstream elements contain three distinctive protein binding sites, two of which appear to be recognized by the Sp1 transcription factor and one which interacts with a cellular protein that binds to "CCAAT" sequences. Optimal expression of the thymidine kinase gene appears to require the coordinate interaction of these two types of transcription factors with the three upstream elements of the promoter.