期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2003
卷号：100
期号：21
页码：12247-12252
DOI：10.1073/pnas.2135255100
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：We have mapped the chromosomal binding site distribution of a transcription factor in human cells. The NF-{kappa}B family of transcription factors plays an essential role in regulating the induction of genes involved in several physiological processes, including apoptosis, immunity, and inflammation. The binding sites of the NF-{kappa}B family member p65 were determined by using chromatin immunoprecipitation and a genomic microarray of human chromosome 22 DNA. Sites of binding were observed along the entire chromosome in both coding and noncoding regions, with an enrichment at the 5' end of genes. Strikingly, a significant proportion of binding was seen in intronic regions, demonstrating that transcription factor binding is not restricted to promoter regions. NF-{kappa}B binding was also found at genes whose expression was regulated by tumor necrosis factor , a known inducer of NF-{kappa}B-dependent gene expression, as well as adjacent to genes whose expression is not affected by tumor necrosis factor . Many of these latter genes are either known to be activated by NF-{kappa}B under other conditions or are consistent with NF-{kappa}B's role in the immune and apoptotic responses. Our results suggest that binding is not restricted to promoter regions and that NF-{kappa}B binding occurs at a significant number of genes whose expression is not altered, thereby suggesting that binding alone is not sufficient for gene activation.
