Motor coordination of <i>Sema3F</i> mice after housing in different environmental conditions.

<p>(A-F) Motor coordination deficits were analyzed using the ladder rung test. (A) Under normal housing conditions, <i>Sema3F</i> mutants need significantly more time to cross the ladder with irregularly spaced bars than littermate controls at each time point tested (4 weeks: 11.74 ± 0.86 s, N = 14 vs. 25.58 ± 2.56 s, N = 12, p < 0.001; 8 weeks: 9.48 ± 0.75 s, N = 14 vs. 18.92 ± 1.64 s, N = 12, p < 0.001; 12 weeks: 9.41 ± 0.67 s, N = 13 vs. 18.31 ± 1.89 s, N = 12, p < 0.001, Improvement mut 4–12 weeks: p = 0.03). (B) <i>Sema3F</i> mutants also show a significantly increased number of slips (4 weeks: 1.00 ± 0.22, N = 14 vs. 3.11 ± 0.66, N = 12, p < 0.05; 8 weeks: 1.10 ± 0.23, N = 14 vs. 2.61 ± 0.56, N = 12, p < 0.05; 12 weeks: 0.82 ± 0.14, N = 13 vs. 2.03 ± 0.37, N = 12, p < 0.05). (C) After enriched environment housing starting at birth the motor performance of <i>Sema3F</i> mutants reaches wildtype levels at 8 weeks after birth (4 weeks: 10.37 ± 0.76 s, N = 10 vs. 16.74 ± 1.71, N = 9, p < 0.005; 8 weeks: 12.63 ± 0.90 s, N = 10 vs. 15.85 ± 1.54 s, N = 9, p = 0.14; 12 weeks: 11.00 ± 0.98 s, N = 10 vs. 13.48 ± 1.19 s, N = 9, p = 0.07). (D) These animals never show a significant difference in the number of slips compared to wildtype littermates (4 weeks: 1.00 ± 0.21, N = 10 vs. 1.67 ± 0.49, N = 9, p = 0.36; 8 weeks: 0.83 ± 0.16, N = 10 vs. 1.07 ± 0.17, N = 9, p = 0.31; 12 weeks: 0.47 ± 0.09, N = 10 vs. 0.59 ± 0.15, N = 9, p = 0.50). (E) Enriched environment housing starting at 4 weeks after birth does not improve the motor performance of <i>Sema3F</i> mutants. (4 weeks: 15.19 ± 1.17 s, N = 19 vs. 34.06 ± 2.09 s, N = 11,p < 0.001; 8 weeks: 12.61 ± 1.01 s, N = 19 vs. 23.91 ± 2.17 s, N = 11, p < 0.001; 12 weeks: 11.75 ± 0.62 s, N = 19 vs. 21.55 ± 2.22 s, N = 11, p < 0.001). (F) Also the number of slips from the ladder is significantly increased at each time point after enriched environment housing starting at 4 weeks (4 weeks: 1.81 ± 0.24, N = 19 vs. 5.30 ± 0.59, N = 11, p < 0.001; 8 weeks: 1.00 ± 0.15, N = 19 vs. 2.24 ± 0.32, N = 11, p < 0.005; 12 weeks: 1.00 ± 0.24, N = 19 vs. 2.394 ± 0.3140, N = 11, p < 0.005). Statistical analysis: Mann-Whitney test. * p < 0.05, ** p < 0.005, *** p < 0.001. (G-I) Improved performance in the grid walk test is not caused by alterations in general locomotion or exploratory behavior. At the age of 12 weeks, animals that were housed in normal or enriched housing conditions starting at birth do not reveal any significant differences in the open field test as determined by (G) the total distance that was traveled (NH: 14190 ± 867.2 cm, N = 16 vs. 13350 ± 951.9 cm, N = 20; EE: 13110 ± 871.3 cm, N = 23 vs. 12160 ± 983.2 cm, N = 20; ANOVA: p = 0.53), (H) the locomotion speed (NH: 12.62 ± 0.96 cm/s, N = 16 vs. 12.22 ± 0.95 cm/s, N = 20; EE: 11.73 ± 0.81 cm/s, N = 23 vs. 10.79 ± 0.89 cm/s, N = 20; ANOVA: p = 0.54) and the total number of rearings (NH: 79.00 ± 9.41, N = 16 vs. 95.85 ± 8.82, N = 20; EE: 78.17 ± 8.16, N = 23 vs. 73.25 ± 8.28, N = 20; ANOVA: p = 0.27). Statistical analysis: One-way ANOVA. * p < 0.05, ** p < 0.005, *** p < 0.001.