Inhibition of FoxO1 acetylation by INHAT subunit SET/TAF-Iβ induces p21 transcription

•SET/TAF-Iβ inhibits FoxO1 acetylation.•SET/TAF-Iβ interacts with FoxO1 in INHAT domain dependent manner.•Recruitment of FoxO1 on p21 promoter is increased by SET/TAF-Iβ.•SET/TAF-Iβ induces p21 transcription and apoptosis under oxidative stress. Post-translational modification of forkhead family transcription factor, FoxO1, is an important regulatory mode for its diverse activities. FoxO1 is acetylated by HAT coactivators and its transcriptional activity is decreased via reduced DNA binding affinity. Here, we report that SET/TAF-Iβ inhibited p300-mediated FoxO1 acetylation in an INHAT domain-dependent manner. SET/TAF-Iβ interacted with FoxO1 and activated transcription of FoxO1 target gene, p21. Moreover, SET/TAF-Iβ inhibited acetylation of FoxO1 and increased p21 transcription induced by oxidative stress. Our results suggest that SET/TAF-Iβ inhibits FoxO1 acetylation and activates its transcriptional activity toward p21. FoxO1physically interacts with SET/TAF-Iβ by pull down (1, 2) FoxO1physically interacts with SET/TAF-Iβ by anti tag coimmunoprecipitation (View interaction) SET/TAF-Iβphysically interacts with FoxO1 by anti bait coip (1, 2)