The nuclei were incubated with Micrococcal Nuclease (MNase) (10 μg DNA per 1 unit MNase) to digest genomic DNA to the optimal length (1-2 nucleosomes), followed by sonication to break the nuclear membrane, with the presence of 0.1% SDS. ChIP was performed with anti-Rpb1(Pol II) antibody. Libraries were constructed by RiboBio Co. Ltd. (Guangzhou,China).