title: GSM6716861: Ovary, 3_month-old_mouse03, rep3; Mus musculus; OTHER
library_construction_protocol: Tissues were quickly transferred into cold DPBS, then washed and subjected to manual pulverization via grinded in liquid nitrogen. The pulverized tissues were aliquoted into pre-labelled and pre-chilled 1.5 ml nuclease-free tubes. After that, the powder in each tube was suspended in 1 ml Nuclear Permeabilization Buffer [1 × DPBS, 5% Bovine Serum Albumin, 0.2% IGEPAL CA-630 (Sigma), 1 mM DTT, 1 × Protease inhibitor], and followed by incubation for 3 minutes to isolate the nuclei. The suspension was transferred to a 15 ml centrifuge tubes pre-filled with 5 ml wash buffer, filtered through 40 μm strainers and centrifuged at 600 × g for 5 minutes at 4°C and re-suspended in 1 × DPBS.  For Bone marrow, cells were collected and centrifuged at 300 × g for 5 minutes at 4°C, then suspended in 1 ml Nuclear Permeabilization Buffer and followed by incubation for 6 minutes to isolate the nuclei. The suspension was transferred to 15 ml centrifuge tubes pre-filled with 5 ml wash buffer, centrifuged at 500 × g for 5 minutes at 4°C and re-suspended in 1 × DPBS. Library was performed according to the manufacter's instructions (Hyperactive® Universal CUT&Tag Assay Kit for Illumina, Vazyme). We replaced primers for illumina with primers for MGI, in order to be suitable for the sequencing protocol of DNBSEQ-T7.