Halfter H, Kavety B, Vandekerckhove J, Kiefer F, Gallwitz D
Max-Planck Institute for Biophysical Chemistry, Department of Molecular Genetics, Göttingen, FRG.
EMBO J. 1989 Dec 20;8(13):4265-72. doi: 10.1002/j.1460-2075.1989.tb08612.x.
We report the cloning and sequence analysis of the yeast BAF1 gene which encodes an abundant protein previously shown to act as a transcription activator in the YPT1-TUB2 intergene region. As predicted from the DNA sequence, the highly hydrophilic BAf1 protein is 731 amino acids long and has a molecular mass of 81 748 daltons. The protein product of the cloned BAF1 gene produced in Escherichia coli is able to form specific complexes with DNA fragments containing the conserved element TCN7ACG. The protein binds also to the ABF1-binding site of the B-domain of ARS1, entertaining the possibility that BAF1 and ABF1 are identical proteins. Extensive deletion studies identified the N-terminal two thirds of the Baf1 protein to be required for specific DNA binding. Amino acid substitutions point to the N-terminal sequence CysX7HisX3HisX4CysX4Cys to form an atypical metal-binding 'finger' structure. Disruption of the BAF1 gene is lethal. The existence of five potential Baf1-protein binding sites in the 5' region of the gene suggests the involvement of the Baf1 protein in transcription regulation of its own gene.
我们报道了酵母BAF1基因的克隆及序列分析，该基因编码一种丰富的蛋白质，先前已证明其在YPT1 - TUB2基因间区域作为转录激活因子发挥作用。根据DNA序列预测，高度亲水性的BAf1蛋白长731个氨基酸，分子量为81748道尔顿。在大肠杆菌中产生的克隆BAF1基因的蛋白质产物能够与含有保守元件TCN7ACG的DNA片段形成特异性复合物。该蛋白质还与ARS1的B结构域的ABF1结合位点结合，这使得BAF1和ABF1可能是相同蛋白质的可能性增大。广泛的缺失研究确定BAf1蛋白的N端三分之二对于特异性DNA结合是必需的。氨基酸替换表明N端序列CysX7HisX3HisX4CysX4Cys形成了一种非典型的金属结合“指状”结构。BAF1基因的破坏是致死性的。该基因5'区域存在五个潜在的Baf1蛋白结合位点，这表明Baf1蛋白参与了其自身基因的转录调控。
