Sawadogo M, Roeder R G
Cell. 1985 Nov;43(1):165-75. doi: 10.1016/0092-8674(85)90021-2.
A gene-specific transcription factor, called USF, has been partially purified from HeLa cell nuclear extracts. Addition of USF results in a 10 to 20 fold increase in transcription from the adenovirus major late promoter in an in vitro system reconstituted with transcription factors TFIIB, TFIID, TFIIE, and RNA polymerase II. Binding of USF to the promoter inhibits DNAase I cleavages over a 20 base pair region just upstream of the -45 to +35 region shown previously to interact with TFIID. More discriminating footprint analyses using methidiumpropyl-EDTA-Fe(II) as the cleaving agent indicate that USF interacts primarily with the small palindromic DNA sequence GGCCACGTGACC located between positions -63 and -52 of the major late promoter, while TFIID interacts primarily with a 10 base pair DNA region centered on the consensus TATA sequence. Dissociation rate measurements indicate a cooperative interaction between USF and TFIID when simultaneously bound to the promoter DNA.
一种名为USF的基因特异性转录因子已从HeLa细胞核提取物中部分纯化出来。在由转录因子TFIIB、TFIID、TFIIE和RNA聚合酶II重构的体外系统中,添加USF会导致腺病毒主要晚期启动子的转录增加10至20倍。USF与启动子的结合会抑制DNA酶I在先前显示与TFIID相互作用的-45至+35区域上游20个碱基对区域内的切割。使用甲基丙基-EDTA-铁(II)作为切割剂进行的更具区分性的足迹分析表明,USF主要与主要晚期启动子-63和-52位之间的小回文DNA序列GGCCACGTGACC相互作用,而TFIID主要与以共有TATA序列为中心的10个碱基对DNA区域相互作用。解离速率测量表明,当USF和TFIID同时结合到启动子DNA上时,它们之间存在协同相互作用。