SOL muscles from Ctrl or YY1dKO mice were subjected to measurement of maximal isometric tetanic force. Left: Representative trace images of normalized tetanic force. (Right): quantification of the force by normalizing with cross-sectional area (CSA). (n = 3 mice, each). Error bars represent s.d.'s of the mean. Student's t-test (two-sided): *P<0.05, **P<0.01, ***P<0.001. 