Johnston M, Davis R W
Mol Cell Biol. 1984 Aug;4(8):1440-8. doi: 10.1128/mcb.4.8.1440-1448.1984.
The GAL1 and GAL10 genes of Saccharomyces cerevisiae are divergently transcribed, with 606 base pairs of DNA separating their transcription initiation sites. These two genes are stringently coregulated: their expression is induced ca. 1,000-fold in cells growing on galactose and is repressed by growth on glucose. The nucleotide sequence of the region of DNA between these genes and the precise sites of transcription initiation are presented here. The most notable feature of the nucleotide sequence of this region is a 108-base-pair guanine-plus-cytosine-rich stretch of DNA located approximately in the middle of the region between GAL1 and GAL10. Analysis of the effects of mutations that alter the region between these two genes, constructed in vitro or selected in vivo, suggest that these guanine-plus-cytosine-rich sequences are required for the expression of both genes. The region of DNA between GAL1 and GAL10 is sufficient for regulation of expression of these genes: fusion of the region to the yeast HIS3 gene places HIS3 under GAL control.
酿酒酵母的GAL1和GAL10基因呈反向转录，它们的转录起始位点之间相隔606个碱基对的DNA。这两个基因受到严格的共调控：在以半乳糖为碳源生长的细胞中，它们的表达被诱导约1000倍，而在以葡萄糖为碳源生长时则受到抑制。本文给出了这两个基因之间的DNA区域的核苷酸序列以及转录起始的精确位点。该区域核苷酸序列最显著的特征是一段富含鸟嘌呤和胞嘧啶的108个碱基对的DNA片段，大约位于GAL1和GAL10之间区域的中部。对体外构建或体内筛选的改变这两个基因之间区域的突变效应的分析表明，这些富含鸟嘌呤和胞嘧啶的序列是这两个基因表达所必需的。GAL1和GAL10之间的DNA区域足以调控这些基因的表达：将该区域与酵母HIS3基因融合可使HIS3受GAL调控。
