Deletion of Tmod1 impairs locomotor activity in mice. (A and B) Voluntary activity in 5–7-mo-old mice was monitored over three consecutive light cycles (12 h off and 12 h on). The number of wheel counts and laser beam breaks was substantially lower in Tmod1^−/−Tg+ animals. (C and D) Muscle strength in mice of various ages was assessed using the hanging wire and grip strength tests. No significant differences in time before falling or grip force were found at any age. (E) Motor coordination was assessed using the rotarod test. No differences in angular speed before falling were found in 1–2-mo-old animals and >12-mo-old animals, but a slight decrease in coordination is evident in 4- and 6-mo-old Tmod1^−/−Tg+ animals. *, P < 0.05; **, P < 0.01; ***, P < 0.001. n = 6 (in A and B) or n = 8 (in C–E) mice/genotype. Data are mean ± SD.