design: A 3-mm biopsy punch was employed to collect the newly formed tissues at the wounding site at 15 dpi. For ATAC-seq in rats, the intact tissues (0 dpi) and the newly formed tissues at the wounding site at 10 dpi were collected. Three biological replicates were involved in each experiment, and five animals were used for each replicate. The fresh tissues were then subjected to tissue dissociation processes using the protocol described in the scRNA-seq studies. The dissociated single cells were collected and used for ATAC-seq by following the manufacturers protocol of the Hyperactive ATAC-Seq Library Prep Kit for Illumina (Vazyme, TD711).