library_construction_protocol: Following euthanasia, dorsal skin was aseptically excised and subcutaneous tissue was removed using a sterile scalpel. The skin was incubated in 0.3% Dispase solution (prepared in PBS) at 4°C overnight to separate the epidermis from the dermis. The epidermal layer was carefully dissected, minced into fine fragments, and digested in 0.05% Trypsin (diluted in PBS) at 37°C for 15 minutes. Trypsin activity was neutralized by adding 0.5% bovine serum albumin (BSA) solution. The cell suspension was filtered through a 40-μm cell strainer to remove debris and centrifuged at 300 × g for 10 minutes at 4°C. Pelleted cells were washed once with 0.04% BSA and finally resuspended in 0.04% BSA. Cells were stained with 0.4% Trypan blue (Thermo Fisher: 14190144) to check the viability on Countess® II Automated Cell Counter (Thermo Fisher). The cell suspension was maintained on ice for subsequent experiments. Single cells and 10x Chromium beads (with UMIs and cell barcodes) were co-encapsulated in GEMs at near-saturation loading. Following cell lysis, polyadenylated RNAs were captured on beads via hybridization. Beads from all GEMs were pooled for reverse transcription, generating cDNA molecules tagged at the 5' end (corresponding to transcript 3' ends) with cell-specific barcodes and UMIs. Beads were then subjected to second-strand cDNA synthesis, adaptor ligation, and universal amplification. All the remaining procedures including the library construction were performed according to the standard manufacturer's protocol (Chromium Single Cell 3ʹ v3.1). Sequencing libraries were quantified using a High Sensitivity DNA Chip (Agilent) on a Bioanalyzer 2100 and the Qubit High Sensitivity DNA Assay (Thermo Fisher Scientific). The sequencing were sequenced on Illumina Novaseq Xplus using PE150 mode.