C/EBPε is acetylated in neutrophil progenitors. (A) COS cells were transfected with Flag-C/EBPε or Flag-C/EBPε K15xR, followed by Flag immunoprecipitation. Cell lysates were analyzed by WB, using anti-acetylated lysines (AcK) and anti-Flag antibodies. (B) NB4 cells were treated with retinoic acid over the course of 4 days. HL60 cells and NB4 cells were treated with KDACi over the course of 3 hours, followed by AcK immunoprecipitation. Cell lysates were analyzed by WB, using anti-C/EBPε and AcK antibodies. (C) PLA was performed in CD34⁺-derived neutrophil progenitors, probed for C/EBPε and AcK. The PLA signal (red dots) represents acetylation of C/EBPε. (D) Magnified view of PLA signal. Data are representative of at least 3 independent experiments. IP, immunoprecipitation; WB, western blot; WCL, whole-cell lysate. #, a specific band.