Fig. 5.

Fsp27/CIDEC is a CREB target gene. A: CIDEC (left panel) and PEPCK (right panel) mRNA levels in HepG2 cells pretreated for 1 h with 50 µM H89 (PKA inhibitor) and treated with 10 µM forskolin (FSK) in OPTI-MEM (Invitrogen), or vehicle (DMSO) for 6 h. B: CIDEC (left panel) and PEPCK (right panel) mRNA levels in HepG2 cells transfected for 48 h with pcDNA3 or KCREB and treated with 10 µM forskolin (FSK) or vehicle (DMSO) for the last 6 h before harvesting. Results are means of ± SEM (n = 3 independent experiments). **P < 0.01, ***P < 0.001 relative to control, #P < 0.05, relative to FSK-treated cells transfected with empty vector; ##P < 0.01 and ###P < 0.001 relative to FSK-treated cells. C: HepG2 cells transfected for 48 h with pGL3b (control) or mouse Fsp27 promoter constructs cloned in pGL3-basic and cotransfected with either pcDNA3 or pcDNA3-CREB expression vectors, represented by fold activation to pcDNA3 (WT promoter construct). A scheme of the mouse Fsp27 promoter-luciferase reporter construct is shown (shadow box indicates CRE elements, crossed shadow box indicates the construct in which CRE elements were mutated). pGL3-basic activation was subtracted from each condition. Results are means of four independent experiments performed in duplicate (*P < 0.05, **P < 0.01, ***P < 0.001 relative to pcDNA3; #P < 0.05, ##P < 0.01 relative to CREB activation of WT promoter).