Research Paper Volume 8, Issue 11 pp 2667—2688

Figure 6. BubR1 insufficient mice exhibit impaired motor function. (A) Gait analysis. The interlimb coordination was analyzed by the Tread-Scan Gait Analysis System. Left: Examples of severe gait abnormality in BubR1^H/H mice. Middle: Quantification of symmetry by regularity index (front/rear step). Right: Quantification of homologous coupling (left/right step). (B) Locomotion in open field. Left: Representative exploratory activity traces from WT and BubR1^H/H mice. Middle: Quantification of the total distance travelled. Right: Quantification of the mean velocity. Reduced distance moved in the open field chamber is a measure of reduced spontaneous locomotor activity. (C) Hindlimb clasping test. BubR1^H/H mice exhibit increased hind limb clasping, indicating a motor function abnormality. (D) Paw grip endurance (PaGE) test, a measure of balance and endurance, indicates BubR1^H/H fall sooner than WT littermates. (E) Grip strength test. All-paw grip strength is significantly reduced in BubR1^H/H mice. (F) Rotarod test. Performance on a fixed speed rotarod paradigm at 10 rpm was assessed. Quantification of the latency to fall on the rotating platform was significantly reduced in BubR1^H/H mice. (G) Grid walking test. BubR1^H/H mice exhibit increased total foot slips in the grid walking test. All values represent mean ± SEM (*P < 0.05, **P < 0.01, ***P < 0.001, two-tailed student’s t-test). Number associated with bar graphs indicates number of animals examined.