Figure 2.
Loss of ERRα and ERRγ Impairs BAT Thermogenic Capacity without Affecting Adipogenesis or BAT Identity
(A) Gross morphology of interscapular BAT depots from WT and ERRαγAd−/− mice.
(B) H&E staining of BAT at 400× magnification.
(C) Electron microscopy of mitochondria and surrounding lipid droplets in BAT. L, lipid droplet.
(D–I, L, and M) Relative mRNA levels of genes involved in mitochondrial morphology and cristae structure (D), adipogenesis and BAT identity (E), OxPhos and TCA cycle (F), fatty acid (FA) oxidation (G), FA biosynthesis and storage (H), thermogenesis (I), nuclear regulation of the mitochondrial oxidative metabolism program (L), and mitochondrial regulation of mitochondrial biogenesis (M).
(J) Western blot of Ucp1 protein and RAN (loading control).
(K) Body temperature of WT and ERRαγAd−/− female mice either at 30°C or moved from 30°C to 4°C for 2.5 hr (n = 5). **p < 0.01, ***p < 0.001 vs. WT 4°C.
Mice were born and raised at thermoneutrality (30°C) and euthanized at 12 weeks of age. mRNA data are from male and female mice combined and normalized to Ppia (n = 7–18). Protein data shown here are from male mice. Data are mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001 vs. WT BAT. See also Figure S2 and Table S3.