(A) Serum total T4 and TSH were measured, and gene expression of Cga, Tshβ subunit, and Trhr in the pituitary were quantified by qPCR in control and UBC-SKO male mice 12 weeks after tamoxifen treatment (1st and 2nd cohort). (B) mRNA expression levels of T3-target genes in the liver, heart, skeletal muscle, and brown adipose tissue (BAT taken from 2nd cohort mice) were quantified by qPCR. (C) Heart rate (HR) was measured weekly by cardiac echocardiography in the 1st cohort mice weekly. For panels A and B, the data were analyzed by unpaired t-test. Panel C was analyzed by Repeated-Measures Two-way ANOVA. Results are shown as the mean±SEM, and the p-values as; ****, p< 0.001; **, p< 0.01; *, p< 0.05. 1st cohort included n = 6–7 mice/group, and 2nd cohort included n = 6–8 mice/group.