Genome-wide location analysis by pull down of in vivo biotinylated transcription factors.

Recent development of methods for genome-wide identification of transcription factor binding sites by chromatin immunoprecipitation (ChIP) has led to novel insights into transcriptional regulation and greater understanding of the function of individual transcription factors. ChIP requires highly specific antibody against the transcriptional regulator of interest, and availability of suitable antibodies is a significant impediment to broader application of this approach. This limitation can be circumvented by tagging the transcriptional regulator of interest with a short bio epitope which is specifically biotinylated by the E. coli enzyme BirA. The biotinylated transcription factor can then be selectively pulled down on streptavidin beads under stringent conditions. This unit provides a detailed protocol for genome-wide location analysis of in vivo biotinylated transcription factors by streptavidin pull-down followed by high-throughput sequencing (bioChIP-seq).