PRKN and Parkinson disease: Taking into consideration that regulation of the mitochondrial life cycle is one of the most important molecular functions of parkin (Ryan et al., 2015; Hammerling et al., 2017), and that the accumulation of dysfunctional mitochondria is directly responsible for inducing neuronal cells death in PD patients with parkin gene mutations (Narendra et al., 2008; Burman et al., 2012; de Vries and Przedborski, 2013), α-Syn-induced parkin downregulation may be the major cause of mitophagy disruption and the accumulation of malfunctioning mitochondria.