PRKN and Parkinson disease: Instead, Koentojoro et al., 2016 have previously shown that the mitochondrial receptor Nip3-like protein X (Nix) has a protective role in PINK1- and Parkin-related PD patient cell lines and observed preserved mitochondrial function due to the Nix function in an asymptomatic loss-of-function Parkin mutation carrier who did not develop PD into her eighth decade [65,66].