library_construction_protocol: For CUT & RUN,cell nuclei were isolated and incubated with an anti-ATF4 antibody (Cell Signaling, 11815S) and normal Rabbit IgG (Cell Signaling, 2729S) overnight at 4ºC while shaking. The nuclei were incubated with protein A-micrococcal (pA-MNase) nuclease for 1 h at 4ºC. Nuclei were equilibrated to 0ºC, and MNase digestion was allowed to proceed for 30 min. Soluble chromatin CIT&RUN fragments were isolated and purified by AMPure XP beads (Beckman, Brea, CA, USA). CUT&RUN libraries were prepared using NEBNext Ultra II DNA (Biolab: Lot 10211572) and its accompanying instructions.