(A) An age-dependent decline in climbing score was observed in flies expressing αSyn in neurons. αSyn expression was induced by the pan-neuronal nSyb-GAL4 driver. (B) Climbing scores at 3 weeks. Flies expressing either A53T, E46K, G51D, or H50Q αSyn showed a significant decrease in locomotor function compared with control flies, whereas flies expressing WT αSyn did not. (C) Climbing scores at 5 weeks. Flies expressing each of the five forms of αSyn, except for A30P, showed lower climbing scores than control flies. The scores of mutant αSyn-expressing flies were not significantly different from WT αSyn-expressing flies. *P < 0.05, **P < 0.01, and ***P < 0.001 vs control flies (one-way ANOVA followed by the Dunnett’s post hoc test). All error bars indicate s.e.m. Fly genotypes are the same as those in Fig 1C. Control fly genotype: +, +/Y;;nSyb-GAL4/+.