ATAC-seq is a high-throughput sequencing method for analysis of genome-wide chromatin accessibility, which is important for global epigenetic control of gene expression. Sequencing adapters are inserted into open chromatin regions by hyperactive Tn5 transposase. After PCR amplification, a sequencing library is constructed. All the open chromatin regions can be obtained under a specific space-time condition, not only limited to the binding sites of a transcription factor, or a certain histone modified region.