Synergism between cAMP and PPAR Signalling in the Initiation of UCP1 Gene Expression in HIB1B Brown Adipocytes
Luciferase reporter assay showing the effect of forskolin and rosiglitazone on (a) 3.1 kbp UCP1-Luc, (b) 260 bp UCP1-Luc, (c) 2.6 kbp PGC1-Luc, (d) 264 bp PGC1-Luc, (e) CRE-mut 2.6 kbp PGC1-Luc, (f) , and (g) , promoter activities. HIB-1B cells were grown to confluence and then transiently transfected with the above -pGL3-Luc reporter construct, as indicated. Twenty-four hours later, cells were treated with DMSO (control), rosiglitazone (10 M) for 24 hours, or forskolin (10 M) for the final 12 hours of rosiglitazone treatment, in serum-free medium, before luciferase activity was measured. Values were expressed as fold increase of ratio of firefly to renilla. Error bar means the mean sem. of three observations within a single experiment performed in triplicate. *** Significant difference , respectively, with respect to control; ### significant difference from wildtype due to the mutation of CRE.