Expression of parkin suppresses α- synuclein -induced loss of climbing ability. Panel A – Aged flies that express parkin and α-synuclein climb significantly better than flies that express α-synuclein (P < 0.001, one-way analysis of variance with supplementary Newman-Keuls test). Genotypes are w1118; UAS-α-synuclein/+; Ddc-Gal4/+ (green open square), w1118; UAS-α-synuclein/+; UAS-parkin1.1/Ddc-Gal4 (red open triangle), w1118; UAS-α-synuclein/+; UAS-parkin2.1/Ddc-Gal4 (blue upside down open triangle). The error bars show the standard error of the mean of twenty trials at each point. Please note that the error bars are mostly within the symbols. B – The life span of flies that express α-synuclein with and without parkin does not differ. The genotypes are marked the same as in panel A.