Lalonde B, Arcangioli B, Guarente L
Mol Cell Biol. 1986 Dec;6(12):4690-6. doi: 10.1128/mcb.6.12.4690-4696.1986.
Several site-directed mutagenesis regimens were used to generate single- and multiple-base substitutions in the upstream activation site UAS1 of the Saccharomyces cerevisiae CYC1 gene. Mutations resulting in large reductions in activity of the site lie in two distinct regions. Six single-base changes in a region A, between -288 and -285, all resulted in a 15-fold reduction in activity. Synthetic sites built up solely of multimers of the -289 to -285 sequence ACCGA behaved as carbon catabolite-sensitive UASs. In addition, substitution mutations in a second region, at nucleotides -266 and -265, virtually eliminated UAS1 activity. These mutations abolished the binding of a heme-dependent protein factor in vitro. Thus, UAS1 contains two essential regions both of which are required for its activity.
使用了几种定点诱变方案，在酿酒酵母CYC1基因的上游激活位点UAS1中产生单碱基和多碱基取代。导致该位点活性大幅降低的突变位于两个不同区域。在区域A（-288至-285之间）的六个单碱基变化，均导致活性降低15倍。仅由-289至-285序列ACCGA的多聚体构建的合成位点表现为对碳分解代谢物敏感的UAS。此外，在第二个区域（核苷酸-266和-265处）的取代突变几乎消除了UAS1活性。这些突变在体外消除了一种血红素依赖性蛋白质因子的结合。因此，UAS1包含两个对其活性必不可少的区域。
