Transgenic mice overexpressing alpha-synuclein, which partially mimics sporadic PD, show elevated levels of SNO-PINK1 as well as defective mitochondrial quality control [43]; in contrast, alpha-synuclein knockout cells and mice are resistant to the deleterious effects of reactive nitrogen species (RNS) generated through exposure to MPP+ or lipopolysaccharide [122]. Here, PINK1 is linked to Parkinson disease.