PRKN and Parkinson disease: In contrast, parkin- and PINK1-mutant fly models have shown a more clear-cut PD phenotype, including mitochondrial dysfunction as well as dopaminergic neuronal loss, significant motor disabilities and reduced lifespan (Greene et al., 2003; Pesah et al., 2004; Clark et al., 2006; Yang et al., 2006; Burman et al., 2012).