REV-ERBβ-deficient mice exhibit an altered metabolic phenotype and feeding schedule.

<p><b>(A)</b> Real-time respiratory exchange ratio (RER) monitoring of pre-acclimated male WT (black square) versus REV-ERBβ KO mice (gray circles) using indirect calorimetry. Mice were fed normal chow over a 3 day period. (F(380,4568) = 5.475, p<0.0001). <b>(B)</b> Average RER value, <b>(C)</b> energy expenditure, and <b>(D)</b> infrared activity beam break counts, indicating movement, for day versus night of the mice in panel A. (n = 7 per group). <b>(E)</b> Food intake measurements of male WT (black square) versus male REV-ERBβ KO mice (gray circles) fed normal chow over a 2 day period. <b>(F)</b> Average fasting RER value taken from a 6 hour period during the fast. (n = 7 per group) Data are representative of 2 independent experiments demonstrating similar results. Experiments using female mice demonstrated similar results (data not shown). Values are mean±s.e.m. Average RER was obtained using ANCOVA (analysis of covariance)[<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0196787#pone.0196787.ref038" target="_blank">38</a>] with ambulatory activity used as a covariate. Statistical significance was assessed using two-way ANOVA or Student’s two-tailed <i>t-</i>tests. <i>* p</i><0.05, ** <i>p</i><0.01, *** <i>p</i><0.005.