library_construction_protocol: WT and DKO mice were euthanized by CO2 inhalation. The aortas were isolated after perfusion with 30 mL of PBS through left ventricular and quickly transferred to cold DMEM medium. Aortas from the two groups were cut into about small pieces and digested with an enzyme solution (5mg/mL collagenase type I, 5mg/mL collagenase type IV, and 5mg/mL liberase) for 90min at 37 °C on a shaker. The digested cell suspension was filtered through a 40 μm strainer and washed twice with PBS. The cells were resuspended and ready for sequencing in PBS with 0.04% bovine serum albumin, and their viability was over 90%. Single-cell RNA-Seq library construction was performed using the protocol provided by 10X Genomics. In brief, the single-cell suspensions from both groups, reagents, gel beads and partitioning oil were loaded to 10X Chromium Chip G to generate single-cell Gel Beads-in-emulsion (GEMs, Single cell 3' Reagent Kits v3.1, 10X Genomics). scRNA was barcoded through reverse transcription in individual GEMs followed by a post GEM-RT cleanup and cDNA amplification. Then, a 3'-gene expression library construction was performed. Finally, the library was sent for sequencing.