The relationship between the "TATA" sequence and transcription initiation sites at the HIS4 gene of Saccharomyces cerevisiae.
The relationship between the "TATA" sequence and transcription initiation sites at the HIS4 gene of Saccharomyces cerevisiae.
复制标题
酿酒酵母HIS4基因的“TATA”序列和转录起始位点之间的关系。
DOI：
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发表时间：
1985
影响因子：
11.1
通讯作者：
G. Fink
中科院分区：
文献类型：
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作者：
F. Nagawa;G. Fink
HIS4基因的转录始于ATG开始翻译的-60位的一个位点(I)。我们在5'非编码区插入/删除连接子，以确定转录起始特异性所需的元件。虽然有4个序列以TATA开头并靠近转录开始（-170,-132，-123和-102），但只有-123 （TATA-123）的序列是转录起始所必需的。通过将合成的寡核苷酸插入到TATA-123缺失的突变体中，我们发现TATA或TATAA不起作用，而TATAAA的功能几乎与野生型序列一样好。这个六音体在相反的方向上不起作用（TTTATA）。当合成TATA序列位于正常位点的上游时，即使存在TATA-123，起始位点也会以大致几何的方式向上游移动。对TATA序列与野生型转录起始位点（I位点）之间距离发生改变的菌株的转录本分析表明，在酵母中，与高等细胞不同，转录不会在TATA序列的严格定义距离处启动。改变TATA和I位点之间的距离或去除I位点的结构改变了转录起始的模式，而不影响HIS4的表达水平。消除I位点的缺失会产生异质转录本，而大大缩短TATA-123与I位点之间距离的缺失会在I位点下游的多个位点开始。因此，TATA和它的下游序列决定了转录起始的模式。
Transcription of the HIS4 gene begins at a single site (I) at position -60 from the ATG that begins translation. We have made linker insertions/deletions in the 5' noncoding region to identify the elements required for the specificity of transcription initiation. Although there are four sequences that begin TATA and are near the start of transcription (-170, -132, -123, and -102) only the sequence at -123 (TATA-123) is required for transcription initiation. By inserting synthetic oligonucleotides into a mutant from which TATA-123 had been deleted, we found that just TATA or TATAA does not work but that TATAAA functions almost as well as the wild-type sequence. This hexamer does not work in the opposite orientation (TTTATA). When a synthetic TATA sequence is placed upstream from the normal site, the site of initiation also moves upstream in a roughly cometric way even when TATA-123 is present. Analysis of transcripts in strains where the distance between the TATA sequence and the wild-type site of transcription initiation (I site) has been altered shows that in yeast, unlike higher cells, transcription does not initiate at a strictly defined distance from the TATA sequence. Constructions that alter the distance between the TATA and the I site or remove the I site change the pattern of transcription initiation without affecting the level of HIS4 expression. Deletions that eliminate the I site produce heterogeneous transcripts and deletions that substantially shorten the distance between TATA-123 and the I site initiate at multiple sites downstream from the I site. Thus, both the TATA and the sequences downstream from it determine the pattern of transcription initiation.