Fig. 4.

Open field analysis and rotarod tests revealed decreased exploratory behavior and decreased motor learning in Mecp2-heterozygous and Mecp2-null mice aged 5–7 weeks of age and in Mecp2-heterozygous mice that were 4 or 7 months of age. At 5–7 weeks of age, distanced traveled in the open field by Mecp2-null mice (n = 8) and Mecp2-heterozygous mice (n = 6) was not different from WT mice (n = 14) (Fig. 5A), nor were there differences in distanced traveled between 4 and 7 months old Mecp2-heterozygous (n = 8) and WT mice (n = 8) (Fig. 5B). Fig. 5C At 5–7 weeks of age, Mecp2-null mice showed decreases in rearing behavior compared to WT mice (red***) and Mecp2-het mice (blue*). Fig. 5D Both 4 and 7 months old Mecp2-het mice exhibited less rearing than WT mice (**, * respectively). Fig. 5E Compared to 5–7 weeks old WT mice, Mecp2-null mice showed initial deficits in rotarod performance that dissipated with training (* both Day 1 and Day 2). Rotorod performance in Mecp2-heterozygous mice was not different from the WT at 5–7 weeks of age but did show persistent deficits at 4 (light blue**, ***, * compared to 4 months old WT mice) and 7 months of age (Fig. 5F; blue***, ****, **** compared to 7 months old WT mice)). *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.