Pinkham J L, Olesen J T, Guarente L P
Mol Cell Biol. 1987 Feb;7(2):578-85. doi: 10.1128/mcb.7.2.578-585.1987.
Activation of the CYC1 upstream activation site (UAS2) and other Saccharomyces cerevisiae genes encoding respiratory functions requires the products of the regulatory loci HAP2 and HAP3. We present here the DNA sequence of the yeast HAP2 gene and an initial investigation into the function of its product. The DNA sequence indicated that HAP2 encoded a 265-amino-acid protein whose carboxyl third was highly basic. Also found in the sequence was a polyglutamine tract spanning residues 120 to 133. Several experiments described herein suggest that HAP2 encodes a direct activator of transcription. First, a bifunctional HAP2-beta-galactosidase fusion gene was localized to the yeast nucleus. Second, a lexA-HAP2 fusion gene was capable of activating transcription when bound to a lexA operator site. The additional requirement for the HAP3 product in activation is discussed.
CYC1上游激活位点（UAS2）以及酿酒酵母中其他编码呼吸功能的基因的激活需要调控基因座HAP2和HAP3的产物。我们在此展示酵母HAP2基因的DNA序列，并对其产物的功能进行初步研究。DNA序列表明，HAP2编码一个265个氨基酸的蛋白质，其羧基端三分之一高度碱性。序列中还发现了一个跨越第120至133位残基的聚谷氨酰胺序列。本文所述的几个实验表明，HAP2编码一种直接的转录激活因子。首先，一个双功能HAP2-β-半乳糖苷酶融合基因定位于酵母细胞核。其次，一个lexA-HAP2融合基因在与lexA操纵位点结合时能够激活转录。文中还讨论了激活过程中对HAP3产物的额外需求。
