释义：

The method combines a modified chromatin immunoprecipitation (ChIP) procedure, with DNA microarray analysis. Cells are fixed with formaldehyde, harvested, and disrupted by sonication. The DNA fragments cross-linked to a protein of interest are enriched by immunoprecipitation with a specific antibody. After reversal of the cross-links, the enriched DNA is amplified and labeled with a fluorescent dye (Cy5) by using a ligation-mediatedpolymerase chain reaction (LM-PCR). In parallel a sample of DNA that is not enriched by immunoprecipitation is subjected to LM-PCR in the presence of a different fluorophore (Cy3), and both immunoprecipitation (IP)-enriched and unenriched pools of labeled DNA were hybridized to a single DNA microarray containing a set of intergenic sequences. The ratio of the Cy5 to Cy3 fluorescence intensities measured at each DNA element in the microarray provided a measure of the extent of binding of the transcription factor to the corresponding genomic locus.

该方法结合了改良的染色质免疫共沉淀 (ChIP) 程序和 DNA 微阵列分析。细胞用福尔马林固定，收获并通过超声破碎。与感兴趣的蛋白质交联的 DNA 片段通过与特定抗体的免疫共沉淀富集。反交联后，富集的 DNA 通过使用连接介导的聚合酶链反应 (LM-PCR) 进行扩增并标记上荧光染料 (Cy5)。 同时，不通过免疫共沉淀富集的 DNA 样本在不同的荧光团 (Cy3) 存在下进行 LM-PCR，并将富集的和未富集的标记 DNA 库都杂交到包含一组基因间序列的单一 DNA 微阵列中。通过在每个 DNA 元素中测量 Cy5 和 Cy3 的荧光强度比，提供了转录因子与相应基因组位点结合程度的量度。