Transcriptional control of c-Myc by c-Jun~Fra-2 in the liver. A. Immunoblot analyses of c-Myc in liver extracts from c-Jun~Fra-2hep mice (non-tumoral and tumors) and controls. B. qRT-PCR quantification of c-Myc target genes c-Jun~Fra-2hep livers at 2 months, p<0.05 for each mRNA. C. Schematic of the murine c-myc gene indicating the putative AP-1 binding site elements (TGACTCA) in the promoter and the 3´enhancer (WRE). D. Fra-2 ChIP-qPCR for the c-Myc 3´enhancer (WRE) and promoter in livers from c-Jun~Fra-2hep mutants and controls at 2 months of transgene expression (off Dox at weaning). An AP-1 binding sequence from the Dusp1 promoter and an intergenic area are included as positive and negative controls, respectively. E. Flag and IgG ChIP-qPCR for the c-Myc 3´enhancer (WRE) and an intergenic area in livers from c-Jun~Fra-2hep and Fra-2hep mutants and controls at 2 months. F. Flag ChIP-qPCR for the c-Myc 3´enhancer (WRE) and Dusp1 promoter in livers from c-Jun~Fra-2hep, Fra-2hep mutants and controls at 2 months. G. Functional validation in the murine AML12 liver cell line by transient transfection of Fra-2 or c-Jun~Fra-2 expression vectors, followed by c-myc qRT-PCR (left) or luminescence measurement of a co-transfected c-Myc 3´enhancer luciferase reporter (right). H. c-jun, fra-2 and c-myc qRT-PCR in livers from HBV transgenic mice (HBVtg), lacking c-jun expression (c-JunDli) in the liver compared to c-Jun-proficient HBVtg littermates at 3 months of age. I. c-Myc immunoblot in liver extracts from c-JunDli HBV transgenic mice compared to HBVtg c-Jun-proficient littermates over time. 2 samples from mice not carrying the HBV transgene are included. Tubulin and Actin are used to control immunoblots loading. Bars = means ±SEM, n≥3. * p<0.05, ** p<0.01, *** p<0.001.