Ubiquitous upstream repression sequences control activation of the inducible arginase gene in yeast.
Ubiquitous upstream repression sequences control activation of the inducible arginase gene in yeast.
复制标题
普遍存在的上游抑制序列控制酵母中诱导型精氨酸酶基因的激活。
DOI：
10.1073/pnas.84.12.3997
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发表时间：
1987
影响因子：
11.1
通讯作者：
Cooper,TG
中科院分区：
文献类型：
--
作者：
Sumrada,RA;Cooper,TG
酵母精氨酸酶基因 (CAR1) 的表达对诱导和氮分解代谢物抑制都有反应。调节是通过正向和负向调节 CAR1 转录的序列介导的。短序列 5'-TAGCCGCCGAGGG-3' 具有阻遏物结合位点的特征，在诱导过程中发挥着核心作用。当将包含该上游抑制序列 (URS1) 的片段放置在异源基因 CYC1 上游激活序列的 5' 或 3' 位置时，该片段会抑制基因表达。当 URS 位于 CAR1 侧翼序列的顺式位置时，URS 及其同源阻遏蛋白的作用被 CAR1 诱导所克服。然而，当它位于异源 CYC1 上游激活序列的下游时，没有观察到这一点，表明 URS 功能被与 CAR1 诱导相关的顺式作用元件特异性中和。对不同基因库中序列的搜索表明，URS1 样序列普遍存在于基因调控区域，包括 lambda 噬菌体、酵母、哺乳动物和病毒基因的基因调控区域。在大量情况下，该序列包含在与酵母基因调控的负控制相关的区域中。这些数据表明，这项工作中确定的 URS 是一个通用阻遏物靶位点，显然在转录调控系统的进化过程中一直是保守的。
Expression of the yeast arginase gene (CAR1) responds to both induction and nitrogen catabolite repression. Regulation is mediated through sequences that both positively and negatively modulate CAR1 transcription. A short sequence, 5'-TAGCCGCCGAGGG-3', possessing characteristics of a repressor binding site, plays a central role in the induction process. A fragment containing this upstream repression sequence (URS1) repressed gene expression when placed either 5' or 3' to the upstream activation sequences of the heterologous gene CYC1. Action of the URS and its cognate repressor was overcome by CAR1 induction when the URS was situated cis to the CAR1 flanking sequences. This was not observed, however, when it was situated downstream of a heterologous CYC1 upstream activation sequence indicating that URS function is specifically neutralized by cis-acting elements associated with CAR1 induction. Searches of sequences in various gene banks revealed that URS1-like sequences occur ubiquitously in genetic regulatory regions including those of bacteriophage lambda, yeast, mammalian, and viral genes. In a significant number of cases the sequence is contained in a region associated with negative control of yeast gene regulation. These data suggest the URS identified in this work is a generic repressor target site that apparently has been conserved during the evolution of transcriptional regulatory systems.