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:2007
卷号:104
期号:9
页码:3067-3072
DOI:10.1073/pnas.0611229104
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Protein-binding DNA sequence elements encode a variety of regulated functions of genomes. Information about such elements is currently in a state of rapid growth, but improved methods are required to characterize the sequence specificity of DNA-binding proteins. We have established an in vitro method for specific and sensitive solution-phase analysis of interactions between proteins and nucleic acids in nuclear extracts, based on the proximity ligation assay. The reagent consumption is very low, and the excellent sensitivity of the assay enables analysis of as few as 1-10 cells. We show that our results are highly reproducible, quantitative, and in good agreement with both EMSA and predictions obtained by using a motif finding software. This assay can be a valuable tool to characterize in-depth the sequence specificity of DNA-binding proteins and to evaluate effects of polymorphisms in known transcription factor binding sites.