Acetylation of C/EBPε regulates transcriptional activity. (A) M-CSFR promoter luciferase reporter activity was analyzed in COS cells by the cotransfection of C/EBPε or C/EBPε K15xR with p300 or SIRT1. An empty vector plasmid was used as control. All values were normalized for cotransfected renilla. (B) COS cells were cotransfected with C/EBPε and increasing concentrations of K15xR, followed by analysis of C/EBPε-specific luciferase reporter activity. All values were normalized for cotransfected renilla. (C) COS cells were transfected with Flag-C/EBPε or Flag-C/EBPε K15xR, followed by confocal microscopy imaging using anti-Flag antibody and 4,6 diamidino-2-phenylindole nuclear staining. Untransfected cells were used as control. (D) COS cells were cotransfected with Flag- or HA-tagged C/EBP and Flag- or HA-tagged C/EBPε K15xR, followed by FLAG immunoprecipitation. Cell lysates were analyzed by WB, using anti-HA antibody. IP, immunoprecipitation; WB, western blot; WCL, whole-cell lysate. Data are representative of 3 or more independent experiments; error bars represent standard error of the mean (between experiments). *P < .05; **P < .01.