Hope I A, Struhl K
Cell. 1986 Sep 12;46(6):885-94. doi: 10.1016/0092-8674(86)90070-x.
Yeast GCN4 protein binds specifically to the promoters of amino acid biosynthetic genes and coordinately induces their transcription. Serially deleted GCN4 and hybrid LexA-GCN4 proteins were assayed for specific DNA binding activity in vitro, and for stimulation of transcription in vivo. The specific DNA binding activity resides in the 60 C-terminal amino acids, a basic region of GCN4. However, certain deletions containing the entire DNA binding region are unable to activate transcription and instead act as repressors in vivo. The activation function appears to critically involve just 19 amino acids that are centrally located in an acidic region of GCN4. In addition to their functional separation, the DNA binding and transcriptional activation regions of the protein can be separated physically by elastase cleavage. The implications of these results for the mechanisms of DNA sequence recognition and transcription activation are discussed.
酵母GCN4蛋白特异性结合氨基酸生物合成基因的启动子，并协同诱导其转录。对一系列缺失的GCN4和杂交LexA-GCN4蛋白进行体外特异性DNA结合活性测定以及体内转录刺激测定。特异性DNA结合活性存在于GCN4的60个C末端氨基酸，即一个碱性区域。然而，某些包含整个DNA结合区域的缺失无法激活转录，反而在体内起阻遏作用。激活功能似乎关键涉及位于GCN4酸性区域中心的仅19个氨基酸。除了功能上的分离外，该蛋白的DNA结合和转录激活区域可通过弹性蛋白酶切割在物理上分离。讨论了这些结果对DNA序列识别和转录激活机制的意义。
