Fig. 1: The absence of MCJ protects against obesity increasing interscapular temperature while not affecting the metabolism on chow diet.

A mRNA levels of MCJ in subcutaneous fat from lean individuals (n = 21) and patients with obesity (n = 114). mRNA expression was normalized to the amount of GAPDH mRNA. B Representative immunoblot analysis showing MCJ expression in WATsc (WT CD and HFD n = 4) and BAT lysate (WT and MCJ^KO CD and HFD n = 6) from WT or MCJ^KO CD and HFD-fed mice for 12 weeks. Vinculin protein expression was monitored as a loading control. C WT and MCJ^KO male (8 wk-old) mice were HFD-fed or CD-fed for 12 weeks and metabolic parameters were assayed. D Body weight at the end of diet (WT CD and MCJ^KO CD n = 15; WT HFD n = 10, MCJ^KO HFD n = 9); (E) body weight time course and area under the curve over 8 weeks (WT n = 10; MCJ^KO n = 9), (F) fat mass (WT CD, MCJ^KO CD, WT HFD and MCJ^KO HFD n = 8), (G) lean mass (WT CD, MCJ^KO CD, WT HFD and MCJ^KO HFD n = 8), (H) energy expenditure (EE) corrected by BW and respect to BW over 2-days (WT CD n = 7; MCJ^KO CD n = 8; WT HFD and MCJ^KO HFD n = 12), (I) infrared thermal images and quantification of BAT interscapular temperature (WT CD and MCJ^KO CD n = 10; WT HFD and MCJ^KO HFD n = 6). J Representative histology of BAT lipid content and quantification of lipid droplet average area (WT CD and MCJ^KO CD n = 5; WT HFD and MCJ^KO HFD n = 5). Scale bar: 100 μm. Statistical differences according to a two-sided Student´s t test (A, B, E), one-way ANOVA followed by Tukey’s multiple comparison test (D, F, G, I, J) or two-way ANOVA followed by Sidak’s multiple comparison test (E, H), and analysis of two-way covariance (ANCOVA) with body weight as covariate (H). Values are represented as the mean ± SEM. Source data are provided as a Source Data file. AUC area under curve, BAT brown adipose tissue, CD chow diet, EE energy expenditure, HFD high fat diet, WATsc subcutaneous white adipose tissue.