A comparison of in vivo and in vitro DNA-binding specificities suggests a new model for homeoprotein DNA binding in Drosophila embryos
A comparison of in vivo and in vitro DNA-binding specificities suggests a new model for homeoprotein DNA binding in Drosophila embryos
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DOI：
10.1093/emboj/18.6.1598
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发表时间：
1999-03-15
期刊：
影响因子：
11.4
通讯作者：
Biggin, MD
中科院分区：
文献类型：
--
作者：
Carr, A;Biggin, MD
关于体内转录因子结合的DNA序列的范围知之甚少。使用敏感的紫外线交联技术，我们表明三类同音蛋白在果蝇胚胎中的大多数基因上以显着水平结合。这三个类的特异性彼此不同。但是，它们对任何单个DNA片段的结合水平都不超过5到10倍。在主动转录的基因上，每个类别的体外DNA结合特异性及其体外DNA结合特异性之间存在良好的相关性，相反，在非活动或弱转录基因上没有看到这种相关性。这些基因在体内受到珍珠的结合，即使它们包含许多高亲和力同音蛋白结合位点。基于这些结果，我们建议如何确定同音蛋白DNA结合的体内模式。
Little is known about the range of DNA sequences bound by transcription factors in vivo. Using a sensitive UV cross-linking technique, we show that three classes of homeoprotein bind at significant levels to the majority of genes in Drosophila embryos. The three classes bind with specificities different from each other; however, their levels of binding on any single DNA fragment differ by no more than 5- to 10-fold. On actively transcribed genes, there is a good correlation between the in vitro DNA-binding specificity of each class and its in vitro DNA-binding specificity, In contrast, no such correlation is seen on inactive or weakly transcribed genes. These genes are bound pearly in vivo, even though they contain many high affinity homeoprotein-binding sites. Based on these results, we suggest how the in vivo pattern of homeoprotein DNA binding is determined.