cKO mice fed HFD have enhanced AT browning and improved energy metabolism. Male cKO mice and littermate controls were fed HFD for 16 weeks. Representative hematoxylin and eosin (H & E) staining of pAT and iAT sections and quantitation of adipocyte size in pAT and iAT of cKO and control mice (A). mRNA levels of browning/beige adipogenesis markers examined by RT-qPCR in iAT of cKO and control mice (B). Representative immunohistochemistry staining and quantification of UCP1 expression in pAT and iAT of cKO and control mice treated with β3-agonist (β3-AG, CL316,243) or vehicle control (C). Comprehensive Lab Animal Monitoring System analysis of cKO mice and littermate controls showing VO2 (D), respiratory exchange ratio (E), food intake (F), and activity (G). n = 5 mice/group. TG content quantified in the liver and skeletal muscle of cKO and control mice (H). *P < 0.05, ***P < 0.001. Con, control.