Figure 4. C/EBPα can directly bind to the promoter region of Munc18b. (A) CC16+ cells are transfected with both Munc18b promoter (-2000/200; Munc18b-promS) or empty pGL3-basic vector (Munc18b-vector) and C/EBPα plasmid or its corresponding empty vector control for 48 h, and then the cells are collected for luciferase activity detection. (B) ChIP assay is conducted in CC16+ cells with the anti-C/EBPα antibody. Interaction sites are identified by PCR for two possible C/EBPα binding sites in the Munc18b promoter. (C) Munc18b promoter with wild-type (WT) or mutation of the binding motif 1 or 2, and C/EBPα plasmid are co-transfected into CC16+ cells used in the luciferase assay. ***P < 0.001 vs. pcDNA-ctrl or WT group.