Transcriptional Activity of PGC-1 and NT-PGC-1 Is Differentially Regulated by Twist-1 in Brown Fat Metabolism
Figure 1
Effects of transcriptional regulators on PGC-1α and NT-PGC-1α function. (a) Schematic diagram of PGC-1α and NT-PGC-1α proteins. L1, L2, and L3 represent leucine-rich motifs, one of which (L2) bears the conserved LXXLL sequence that interacts with nuclear receptors. Two white boxes represent the interaction regions of PGC-1α with transcriptional regulators, Twist-1, and RIP140, respectively. (b), (c) Transcriptional repression assay using a luciferase reporter. pcDNA3.1, PGC-1α, and NT-PGC-1α were cotransfected in COS-1 cells with Gal4-ERRα-LBD and RIP140 (b) or PPARγ and Twist-1 (c). Luciferase activity was determined 48 h after transfection and the relative luciferase units were calculated as described in Materials and Methods. Data represent mean ± SEM of at least three independent experiments. Significant difference is determined by student t-test (**; ***; ****; ns: not significant).
