Protein extracts were prepared using RIPA buffer (50 mM/l Tris–HCl pH 7.4, 150 mM/L NaCl, 0.1% sodium dodecyl sulfate (SDS; w/v), 1% sodium deoxycholate (w/v), and 1% Triton X-100 (v/v)) and analyzed by western blotting as previously described (43–45 (link)). Briefly, protein samples were denatured at 100°C for 5 min in the presence of protein loading buffer (62.5 mM Tris–HCl pH 6.8, 10% glycerol (v/v), 0.01% bromophenol blue (w/v), 2.15% SDS (w/v), 1.55% dithiothreitol (w/v), and 5% 2-hydroxy-1-ethanethiol (v/v)), separated on 12% SDS-PAGE gels, and transferred to polyvinylidene fluoride (PVDF) membranes (BioRad, 1620177). Membranes were then processed following the standard ECL protocol (Thermo Fisher Scientific, EI9051). Blots were viewed using Bio-Rad ChemiDoc Imaging System and protein levels were quantified from at least three western blots using ImageJ. Antibodies used were anti-FLAG (Beyotime, AF519; 1:1000 dilution), anti-HDAC1 (Abcam, ab1767; 1:1000 dilution), anti-α-Tubulin (Beyotime, AF0001; 1:2000 dilution), and anti-Histone H3 (Abcam, ab1791; 1:1000 dilution).