After washing in a 6 cm dish with PBS, testes were cut into small pieces to expose the seminiferous tubules. Seminiferous tubules were transferred to a 15 mL tube containing 5 mL dissociation buffer [DMEM with 10% FBS, 1% Pen/Strep, 0.25 mg/mL collagenase/dispase (Roche, 10269638001)] for 30 min incubation at 37°C. Tubes were inverted every 5 min. Seminiferous tubule fragments were collected and washed with PBS by centrifugation at 300 x g for 5 min at room temperature. Seminiferous tubule fragments were passed through a 70 μm cell strainer, and then washed with PBS twice. Testicular cell density and viability were evaluated by using an automated cell counter. 500,000 testicular cells were used for each CUT&RUN reaction by following vendor's instructions (EpiCypher, 14-1048). Sequencing libraries were prepared using the NEBNext® Ultra™ II DNA Library Prep Kit (E7645L).