Open chromatin in plant genomes.

Sensitivity to DNase I digestion is an indicator of the accessibility and configuration of chromatin in eukaryotic genomes. Open chromatin exhibits high sensitivity to DNase I cleavage. DNase I hypersensitive sites (DHSs) in eukaryotic genomes can be identified through DNase I treatment followed by sequencing (DNase-seq). DHSs are most frequently associated with various cis-regulatory DNA elements, including promoters, enhancers, and silencers in both animal and plant genomes. Genome-wide identification of DHSs provides an efficient method to interpret previously un-annotated regulatory DNA sequences. In this review, we provide an overview of the historical perspective of DHS research in eukaryotes. We summarize the main achievements of DHS research in model animal species and review the recent progress of DHS research in plants. We finally discuss possible future directions of using DHS as a tool in plant genomics research.