Identification of a regulatory region that mediates glucose-dependent induction of the Saccharomyces cerevisiae enolase gene ENO2.
Identification of a regulatory region that mediates glucose-dependent induction of the Saccharomyces cerevisiae enolase gene ENO2.
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介导酿酒酵母烯醇酶基因 ENO2 的葡萄糖依赖性诱导的调节区域的鉴定。
DOI：
10.1128/mcb.6.7.2287-2297.1986
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发表时间：
1986
影响因子：
5.3
通讯作者：
Holland,MJ
中科院分区：
文献类型：
--
作者：
Cohen,R;Holland,JP;Yokoi,T;Holland,MJ
有两种酵母烯醇化酶基因，命名为ENO 1和ENO 2，它们在生长于葡萄糖上的营养细胞和生长于产气碳源上的细胞中差异表达。ENO 2在生长于葡萄糖上的细胞中被诱导超过20倍，而ENO 1在生长于葡萄糖上的细胞和生长于产气碳源上的细胞中表达相似。通过缺失作图分析确定了葡萄糖依赖性诱导所需的ENO 2 5′侧翼区序列。这些研究是利用含有ENO 25 ′侧翼序列和ENO 1编码序列的融合基因进行的。该融合基因经历葡萄糖依赖性诱导，并且在以葡萄糖或产气碳源生长的细胞中以与residentENO 2基因相同的水平表达。在ENO 1基因座上整合ENO 1编码序列缺失菌株后，监测ENO 25 ′侧翼区含有缺失突变的融合基因的表达。该分析表明，有两个上游激活位点位于转录起始位点上游461个碱基对位置的上游和下游。这些上游激活位点中的任一个都足以在存在致突变碳源的情况下进行葡萄糖依赖性诱导和正常基因表达。两个调控区的缺失导致基因表达的完全丧失。调节区在相对于编码序列的两个方向上正常发挥功能。构建了在调控区域内含有小缺失的突变融合基因;这些基因在致突变碳源中正常表达，但在葡萄糖存在下不诱导。基于这一分析，ENO 2含有一个顺式作用的调控区，该调控区是基因表达所必需的，并介导葡萄糖依赖性的基因表达诱导。
There are two yeast enolase genes, designatedENO1andENO2, which are expressed differentially in vegetative cells grown on glucose and in cells grown on gluconeogenic carbon sources.ENO2is induced more than 20-fold in cells grown on glucose, whereasENO1expression is similar in cells grown on glucose and in cells grown on gluconeogenic carbon sources. Sequences within the 5′ flanking region ofENO2which are required for glucose-dependent induction were identified by deletion mapping analysis. These studies were carried out by using a fused gene containing theENO25′ flanking sequences and theENO1coding sequences. This fused gene undergoes glucose-dependent induction and is expressed at the same level as the residentENO2gene in cells grown on glucose or gluconeogenic carbon sources. Expression of fused genes containing deletion mutations within theENO25′ flanking region was monitored after integration at theENO1locus of a strain carrying a deletion of the residentENO1coding sequences. This analysis showed that there are two upstream activation sites located immediately upstream and downstream from a position 461 base pairs upstream from the transcriptional initiation site. Either one of these upstream activation sites is sufficient for glucose-dependent induction and normal gene expression in the presence of gluconeogenic carbon sources. Deletion of both regulatory regions results in a complete loss of gene expression. The regulatory regions function normally in both orientations relative to the coding sequences. Mutant fused genes containing small deletions within the regulatory regions were constructed; these genes were expressed normally in gluconeogenic carbon sources but were not induced in the presence of glucose. Based on this analysis,ENO2contains a cis-acting regulatory region which is required for gene expression and mediates glucose-dependent induction of gene expression.