FIG. 7.

(A) Leptin transactivation by C/EBPβ and cooperation with HMGI(Y). Histograms show the luciferase activities of extracts from 293 cells cotransfected with the p(−161)ob-luc reporter and the indicated C/EBPβ and HMGI(Y) plasmids. The mutant m52 reporter plasmid was used as a negative control. (B) Histograms showing the luciferase activities of extracts from 293 cells cotransfected with the RSV-luc reporter and the C/EBPβ and HMGI(Y) plasmids. The relative activities were calculated by dividing the normalized activities by the activity of the m52 and RSV-luc constructs, which has been considered equal to 1. The data represent the average of results of three independent experiments, performed in duplicate, with standard deviations. (C) After transfection, cell lysates were divided into two aliquots. One of these aliquots was used for transactivation assays, and the other was used for Western blot analysis as a control of protein expression. Protein extracts were separated by SDS-PAGE, transferred to Immobilon-P, and immunoblotted with the indicated antibodies.