Gadhavi P L
Cambridge Centre for Molecular Recognition, Department of Biochemistry, University of Cambridge, United Kingdom.
J Protein Chem. 1998 Oct;17(7):591-8. doi: 10.1007/BF02780960.
Limited proteolysis of the DNA-binding domain (residues 1-147) of the yeast transcriptional activator GAL4 has been used to define more precisely the subdomain structure required for DNA binding and dimerization. Two regions of the protein were found to be resistant to proteolysis: the cysteine-rich, zinc-binding region (residues 6-43) and a hydrophobic sequence between residues 52 and 97. Carboxy-terminal deletion fragments of the DNA-binding domain were generated and assayed by DNase 1 footprinting. This showed that the affinity of DNA binding depends on the sequence between residues 65 and 94. Structural comparisons by UV circular dichroism (CD) were made and the difference CD spectra indicate that strong alpha-helical content is found specifically in the region between residues 65 and 94, which previous studies have shown to enable dimerization and in this study the formation of a stable protein-DNA complex.
酵母转录激活因子GAL4的DNA结合结构域（第1至147位氨基酸残基）的有限蛋白酶解已被用于更精确地确定DNA结合和二聚化所需的亚结构域结构。发现该蛋白的两个区域对蛋白酶解具有抗性：富含半胱氨酸的锌结合区域（第6至43位氨基酸残基）和第52至97位氨基酸残基之间的疏水序列。生成了DNA结合结构域的羧基末端缺失片段，并通过DNase 1足迹法进行检测。结果表明，DNA结合亲和力取决于第65至94位氨基酸残基之间的序列。通过紫外圆二色性（CD）进行了结构比较，差异CD光谱表明，在第65至94位氨基酸残基之间的区域特别发现了强烈的α-螺旋含量，先前的研究表明该区域能够实现二聚化，在本研究中能够形成稳定的蛋白质-DNA复合物。
