Behavioral outcome of Piccolo LOF resembles PCH3 symptoms. A, Rotarod performance for Pclo^wt/wt, Pclo^wt/gt, and Pclo^gt/gt rats for 16 trials over 4 d. Pclo^gt/gt rats fell significantly faster than Pclo^w/w on Trials 6 and 8 and faster than both Pclo^wt/wt and Pclo^wt/gt on Trials 9–16. B, Grip strength task for Pclo^wt/wt, Pclo^wt/gt, and Pclo^gt/gt rats for 9 trials over 2 d. No differences were found for forelimb grip strength between the groups. C, Ladder walk task for Pclo^wt/wt, 859 Pclo^wt/gt, and Pclo^gt/gt rats for 3 trials over 1 d. Pclo^gt/gt rats had a higher rate of stepping errors (ladder rung foot slips/misses) than Pclo^wt/wt and Pclo^wt/gt rats. D, Open field task for Pclo^wt/wt, Pclo^wt/gt, and Pclo^gt/gt rats for 1 trial each over 1 d. Pclo^gt/gt rats performed fewer rearing behaviors than Pclo^wt/wt and significantly less than Pclo^wt/gt rats in the perimeter sectors of the arena. Other behaviors, such as crossing the open field and grooming, were not different between the three groups. Animals used in the above experiments are as follows: wt21-wt24; he1-he4; ko20-ko23. E, Locomotor activity of Pclo^wt/wt, Pclo^wt/gt, and Pclo^gt/gt rats during the 12 h dark phase. Pclo^gt/gt rats covered a >50% longer distance than Pclo^wt/wt and Pclo^wt/gt rats. Data points are individual means over 15 nights. F, Performance of Pclo^wt/wt, Pclo^wt/gt, and Pclo^gt/gt rats during the isometric pull-task (handle position 11 mm inside the cage). Only 4 of 11 Pclo^gt/gt rats succeeded at the 60 g force threshold, and Pclo^gt/gt rats pulled with a significantly lower success rate at all force thresholds compared with Pclo^wt/wt and Pclo^wt/gt. Error bars indicate SEM. Data points represent individual rats. For statistical analysis, see Table 1. Animals used in the above experiments are as follows: wt25-wt34; he5-he8; ko24-ko35. *, **, ***, **** describe significance between Pclo^wt/wt and Pclo^gt/gt and #, ##, ### describe significance between Pclo^wt/wt and Pclo^gt/gt.