PRKN and Parkinson disease: In the PD brain, the anomalous activity of parkin (a protein involved in the ubiquitination of proteins and in mitophagy) produces an improper targeting of substrates for proteosomal degradation and in a fragmentation of the mitochondrial network (Lucking et al., 1998, 2000; Moore et al., 2005; Reeve et al., 2014).