Effect of in vivo Deptor KD on skeletal muscle weight and protein synthesis. Gastrocnemius of C57/BL6 mice were electroporated with plasmids containing either scramble (control) shRNA or shRNA targeting Deptor mRNA. (A) Three days after electroporation, the animals were anesthetized and the muscle was excised and homogenized, and mRNA in the homogenate was quantified using real-time PCR. The bar graph shows Deptor mRNA content normalized to rpL32, which serves as an endogenous control. Data are mean ± SE; n = 5–6 for each condition. *P < 0.05, compared with control values. (B) Animals were treated as described above, and then immediately after electroporation, one hindlimb was immobilized to induce disuse atrophy, as described in Materials and Methods. At day 3, muscles were excised. B shows muscle weight and C shows the in vivo-determined rate of protein synthesis. For (B) and (C), values are means ± SE; n = 9–10 for each condition. Means with different superscripts (a, b and c) are significantly different (P < 0.05). Immob, immobilization.