snRNA-seq of dentate gyrus
The mice were perfused with ice-cold PBS, and the dentate gyrus was micro-dissected out and snap frozen in liquid nitrogen. The nuclei were isolated from the snap-frozen dentate gyrus tissue by a series of cellular membrane lysis, differential centrifugation and filtration steps.  Tissues were homogenized in a dounce homogenizer after suspension in 4mL of ice cold lysis buffer containing propidium iodide for nuclear staining (250mM Sucrose, 25mM KCl, 0.05% IGEPAL-630, 3mM MgCl2, 1uM DTT, 10mM Tris pH 8.0). Supernatant was brought to 8mL of total volume with nuclear wash buffer (PBS + 3mM MgCl2 + 0.01% BSA) then filtered sequentially through a 100um and 20 um filter (pluriSelect Life Science). Nuclei were pelleted at 400g for 5 minutes at 4C, washed in 4mL of nuclear wash buffer and repelleted. After removal of wash buffer, nuclei were resuspended in approximately 500uL of cold nuclear resuspension buffer (Nuclear wash buffer + 0.4U/uL of murine RNAse inhibitor (New England Biolabs)) with gentle trituration then counted on a hemocytometer. The 10x Genomics Chromium with v3.1 NextGEM Single Cell 3 Kit was used to generate the single nuclei barcoded emulsions, targeting 8000 nuclei per device. Barcoded libraries were constructed according to the manufacturers protocols using 10X Genomics' NextGEM Single Cell 3' v3.1.