Figure 6.

MT increases SUMOylation level of HDAC1. (A) 293T cells were transfected with HA-tagged HDAC1 and Flag-tagged SUMO1 plasmid, cells treated with MT (2 mM) or the combination of MT and luzindole for 24h as indicated. The SUMOylation of HDAC1 was demonstrated using a PLA in 293T cells. DNA was counterstained with (DAPI, blue). Confocal microscopy was used to detect the interaction (red dots). (B) Number of dots corresponding to SUMOylated HDAC1 per cell from each group in (A). (C) Overexpression of SENP1 could counteract the effect of MT on HDAC1 SUMOylation. (D) Number of dots corresponding for SUMOylated HDAC1 per cell from each group in (C). Each bar in (B) and (D) was based on a statistic of 30 imaged cells. ***P<0.001 versus control group. MT, melatonin; HDAC1, SUMOylation of histone deacetylases 1; PLA, Proximity ligation assay; DAPI, 4’,6-diamidino-2-phenylindole.0