PRKN and Alzheimer disease: Parkin mediates autophagic degradation of defective mitochondria (mitophagy) (Geisler et al, 2010; Narendra et al, 2008; Park et al, 2009; Vives-Bauza et al, 2010), and clears autophagic vacuoles (AVs) in AD and PD models (Khandelwal et al, 2011; Lonskaya et al, 2012a; Lonskaya et al, 2012c), while parkin deletion exacerbates amyloid pathology in AD models (Perucho et al, 2010; Rodriguez-Navarro et al, 2008).