Fig. 2

JNK is necessary for muscle hypertrophy with overload. The distal portion of the gastrocnemius muscle was surgically removed from one limb in muscle JNK knockout (mJNKKO) mice and wild-type controls (WT; MCK-Cre^−/+) to induce functional overload (OVL) of the plantaris muscle. The contralateral limb served as control (CON). a Fourteen days following overload surgery, the plantaris muscles were removed and wet weight was recorded. b Sections from plantaris muscles were stained with wheat germ agglutinin (green) for the calculation of fiber cross-sectional area (CSA). Scale bar represents 100 µm. c, d Average CSA was calculated (c) from the Control and Overload muscles from both genotypes, and fiber size distribution was plotted (d). *P < 0.05, **P < 0.01 vs Control from the same genotype by two-way ANOVA and Sidak’s post hoc testing. Main effects of genotype are displayed with P-values. Each data point represents the results from an individual animal. Bar plots indicate mean ± SEM for all data