Fig. 2.
Minimum phenotypic change in extensor digitorum longus (EDL) muscle of 3-mo-old MGsKO mice. A: SDS-PAGE, glycerol SDS gel, and Western blots showed that EDL, a normally fast-fiber muscle, of 3-mo-old MGsKO mice had slightly increased MHC IIx and barely detectable slow TnI and slow TnT, in contrast to solely fast myofilament protein isoforms in age-matched controls. SOL, soleus muscle. B: the ratio of EDL muscle weight to body weight or to tibial length showed no statistically significant change in MGsKO vs. control groups (P ≥ 0.097). C: twitch contraction showed shorter time to develop peak tension (TPT) in 3-mo-old MGsKO mouse EDL muscle compared with the control, but no difference in the time from maximum twitch force to half-relaxation, T1/2. Values are means ± SE; n = 4 mice in control and n = 5 mice in MGsKO groups. *P < 0.05 vs. control in Student's t-test.