KO mice were protected from food deprivation–induced atrophy. Ten- to 13-wk-old female KO and WT littermate mice were used to demonstrate whether TRB3 is a key molecule to induce food deprivation–induced atrophy. A) TRB3 mRNA expression in TA muscle was determined to confirm the knockout of TRB3. KO and WT mice were divided into Fed and FD groups. B) Percentage change in body weight between groups with access to food (Fed) and food-deprived groups (FD) in both WT and KO mice was determined. C) Percentage of food deprivation–induced atrophy was determined in TA, EDL, SOL, and GAS muscles. A.U., arbitrary unit. Data are the means ± sem (n = 4–6/group). ***P < 0.001 vs. Fed, #P < 0.05, ###P < 0.001 vs. WT.