Lee Y, Gurnon D G, Hollenbeck J J, Oakley M G
Department of Chemistry, Indiana University, 800 East Kirkwood Avenue, Bloomington, IN 47405-7102, USA.
Bioorg Med Chem. 2001 Sep;9(9):2335-9.
bZip transcription factors contain two regions that are required for DNA binding: a leucine zipper dimerization domain and a highly charged basic region that directly contacts DNA. The spacing between these subdomains is strictly conserved, and changes in this spacing result in a loss of function. Using an in vitro selection strategy, we have investigated the ability of a bZip protein with incorrect spacing between these two regions to bind specifically to DNA. Surprisingly, we find that although such a protein does not bind to its predicted site, it is possible to isolate a pool of DNAs that bind with very similar affinity to that of GCN4 for its optimum DNA site.
bZip转录因子包含两个DNA结合所需的区域：一个亮氨酸拉链二聚化结构域和一个与DNA直接接触的高度带电的碱性区域。这些亚结构域之间的间距严格保守，间距的改变会导致功能丧失。我们使用体外筛选策略，研究了在这两个区域之间具有不正确间距的bZip蛋白特异性结合DNA的能力。令人惊讶的是，我们发现，尽管这样的蛋白不与其预测位点结合，但有可能分离出一组DNA，它们与GCN4与其最佳DNA位点结合的亲和力非常相似。
