PRKN and Parkinson disease: Consistently, we found that both mitochondrial morphology (Fig. S3A,B, Supporting information) and axonal integrity (Fig. S3D,E, Supporting information) of Parkin‐overexpressing neurons were significantly improved by co‐expression of Marf. This result is in line with the idea that mitophagy‐independent PINK1‐Parkin functions may cause or contribute to the pathogenesis of PD (Pryde et al., 2016).