Microglial nuclei were first extracted with lysis buffer (0.32 M sucrose, 5 mM CaCl2, 3 mM MgAce2, 0.1 mM EDTA, 10 mM Tris-HCl, pH 8, 0.1% NP-40). Then ATAC-seq library was constructed using the reagents in TruePrep DNA Library Prep Kit V2 for Illumina (Vazyme, TD501-02). The experimental procedure was as follows: nuclei were treated with Tn5 at 37°C for 30 minutes. DNA was then purified with the MinElute Gel Extraction Kit (Qiagen, 28604) and eluted in 27ul EB buffer. 24ul of DNA samples, 10ul of 5XTAB, 5ul of PPM, 1ul of TAE, and selected aptamers (5ul of N5XX and 5ul of N7XX) (Vazyme, TD202) were mixed, followed by PCR amplification. Library DNA was purified and size-selected with SPRIselect beads (Beckman, B23318). Library quality was checked on a Qubit and Agilent 4200 Tapestation. Library was sent to Novogene in China for paired-end sequencing on Illumina XTen (2 × 150bp read length).