Fig. 7.

ERK activation is required for TGR5-mediated mitochondrial fission. a, b Representative (n = 6 per group) western blots of PGC-1α, the mitochondrial marker VDAC1, and beiging markers TBX1 and UCP1, and TGR5 downstream targets (phospho proteins) with their relative controls (CREB, ERK and DRP1) from differentiated adipocytes derived from the stromal vascular fraction (SVF) of TGR5 wild-type (Tgr5^+/+) (a) and germline TGR5 knockout (Tgr5^−/−) (b) mice. PARP1 was used as loading control. Cells were stimulated with the TGR5 agonist INT-777 or vehicle (DMSO) in the presence or absence of the selective ERK inhibitor FR180204. n = 6. c Representative (n = 6 per group) images of TOMM20 immunofluorescence (in green) on preadipocytes derived from the stromal vascular fraction (SVF) of TGR5 wild-type (Tgr5^+/+) and germline TGR5 knockout (Tgr5^−/−) mice. Cells were stimulated as described in a and b. Nuclei were stained with DAPI (in blue). Scale bars = 10 μm. Insets show a reconstruction of the mitochondrial network. n = 6. d Oxygen consumption rate (OCR) of the cells described in a and b. Cellular respiration was measured in basal condition (Basal) and at maximal respiration (FCCP). Results represent mean ± SEM. **P ≤ 0.01 and ***P ≤ 0.001 vs. Tgr5^+/+ cells by one-way ANOVA followed by Bonferroni post hoc test. Uncropped western blots are provided in Supplementary Fig. 15A–E and Supplementary Fig. 16A–E