(A) Kaplan-Meier survival curve. As compared with a placebo DMSO control treatment (n = 4), wortmannin treatment increases median survival of Mtm1 KO mice from 34.5 to 44 days, with maximum survival changed from 35 to 50 days (n = 6, ***P < 0.001). (B) Histopathological assessment of TA muscle tissue of 32-day-old animals reveals that muscle fibers from Mtm1 KO mice treated with wortmannin have modest improvements in myofiber size and central nucleation (top panel, n =2 per treatment group, scale bars: 20 μm). Immunostaining of PI3P on cross section of TA muscle (60×) reveals reduced labeling in wortmannin-treated Mtm1 KO as compared with the intense staining seen in placebo-exposed Mtm1 KO muscle (bottom panel, n =2 per treatment group, scale bars: 20 μm).