Flies also have provided insights into disease mechanisms, including the processing of amyloid precursor protein (APP) and neurotoxicity Aβ42 in Alzheimer’s Disease (Loewer et al. 2004), the interaction of parkin and Pink1 at mitochondria (Greene et al. 2003; Clark et al. 2006) and the spreading of Huntingtin aggregates and subsequent neuronal death (Babcock and Ganetzky 2015), as well as various downstream mechanisms of neurotoxicity in tauopathy (Khurana et al. 2006; Dias-Santagata et al. 2007; Fulga et al. 2007; Loewen and Feany 2010; Frost et al. 2014; Frost et al. 2016). Here, APP is linked to Alzheimer disease.