Genomic studies with Escherichia coli MelR protein:: Applications of chromatin immunoprecipitation and microarrays
Genomic studies with Escherichia coli MelR protein:: Applications of chromatin immunoprecipitation and microarrays
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DOI：
10.1128/jb.186.20.6938-6943.2004
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发表时间：
2004-10-01
影响因子：
3.2
通讯作者：
Busby, SJW
中科院分区：
文献类型：
--
作者：
Grainger, DC;Overton, TW;Busby, SJW
大肠杆菌MelR蛋白是melAB基因的蜜二糖依赖性表达所必需的转录激活因子。我们已经使用染色质免疫沉淀来研究MelR和RNA聚合酶在体内与melAB启动子的结合。我们的研究结果表明，MelR与启动子DNA，无论是在诱导剂蜜二糖的存在和不存在。相比之下，RNA聚合酶仅在诱导物存在下被募集到melAB启动子。MelR DK261阳性对照突变体与melAB启动子结合，但不能募集RNA聚合酶。通过使用Affyssin基因芯片阵列对免疫沉淀的DNA进行进一步分析，表明melAB启动子是大肠杆菌中的主要靶点，如果不是唯一靶点的话。coliMelR.这通过转录组学实验证实，该实验分析了具有或不具有melR的细胞中的RNA。
Escherichia coli MelR protein is a transcription activator that is essential for melibiose-dependent expression of the melAB genes. We have used chromatin immunoprecipitation to study the binding of MelR and RNA polymerase to the melAB promoter in vivo. Our results show that MelR is associated with promoter DNA, both in the absence and presence of the inducer melibiose. In contrast, RNA polymerase is recruited to the melAB promoter only in the presence of inducer. The MelR DK261 positive control mutant binds to the melAB promoter but cannot recruit RNA polymerase. Further analysis of immunoprecipitated DNA, by using an Affymetrix GeneChip array, showed that the melAB promoter is the major, if not the sole, target in E. coli for MelR. This was confirmed by a transcriptomics experiment to analyze RNA in cells either with or without melR.