SATURATION MUTAGENESIS OF A YEAST-HIS3 TATA ELEMENT - GENETIC-EVIDENCE FOR A SPECIFIC TATA-BINDING PROTEIN
SATURATION MUTAGENESIS OF A YEAST-HIS3 TATA ELEMENT - GENETIC-EVIDENCE FOR A SPECIFIC TATA-BINDING PROTEIN
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DOI：
10.1073/pnas.85.8.2691
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发表时间：
1988-04-01
影响因子：
11.1
通讯作者：
STRUHL, K
中科院分区：
文献类型：
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作者：
CHEN, W;STRUHL, K
酵母his3启动子区域包含两类不同的“TATA元件”，组成型（TC）和调节型（TR），它们由它们与上游启动子元件的相互作用、起始位点的选择性和染色质结构来定义。TC定位在-83和-53之间，TR定位在-55和-35之间，在这些区域存在几个类似tata的序列。在这项研究中，我们使用饱和诱变来检测转录诱导所需的his3tr元件的结构要求。为了避免冗余元件的复杂性，使用gal-his3杂交启动子进行表型分析，该启动子的功能取决于含有预期his3 TR元件的短寡核苷酸。在这种情况下，含有TATAAA序列的寡核苷酸足以发挥TR功能。然而，该序列18个可能的单碱基替换中有17个和10个可能的双突变中有9个破坏了TR功能。这种对TR功能的严格序列要求强烈表明TR元件是序列特异性dna结合蛋白的靶位点。此外，由于编码TC和某些其他酵母基因启动子的区域不包含与TR功能兼容的序列，我们认为酵母细胞中含有多个具有不同序列特异性的蛋白质，这些蛋白质执行相关的“TATA功能”，并且酵母启动子可以根据其下游启动子元件划分为类别。
The yeast his3 promoter region contains two distinct classes of "TATA elements", constitutive (TC) and regulatory (TR), that are defined by their interactions with upstream promoter elements, selectivity of initiation sites, and chromatin structure. TC is localized between positions -83 and -53, and TR is localized between positions -55 and -35, regions in which there are several TATA-like sequences. In this study, we used saturation mutagenesis to examine the structural requirements of the his3 TR element necessary for transcriptional induction. To avoid the complications of redundant elements, the phenotypic analysis was carried out by using a gal-his3 hybrid promoter whose function depends on a short oligonucleotide containing the prospective his3 TR element. In this context, an oligonucleotide containing the sequence TATAAA is sufficient for TR function. However, 17 out of the 18 possible single-base substitutions and 9 out of 10 double mutations of this sequence abolish TR function. This strict sequence requirement for TR function strongly suggests that the TR element is a target site for a sequence-specific DNA-binding protein. Further, as the region encoding TC and promoters of certain other yeast genes do not contain a sequence that is compatible with TR function, we suggest that yeast cells contain multiple proteins with distinct sequence specificities that carry out a related "TATA function" and that yeast promoters can be divided into classes based on their downstream promoter elements.