PINK1 points Parkin to mitochondria.

For decades, it has been presumed that mitochondrial dysfunction, in the form of impaired complex I activity, may contribute to the cause of Parkinson disease (PD). ( 1) The discovery that several gene mutations cause familial forms of PD ( 1) has led to a renewed enthusiasm for the mitochondrial hypothesis of PD, but this time from a quite distinct and, perhaps, more realistic angle. Among these genes, those that code for PTEN-induced kinase-1 (PINK1) ( 2) and for the E3-ubiquitin ligase Parkin ( 3) did attract major interest from mitochondriologists, in part, because both proteins interact with each other and apparently function, genetically, within the same molecular pathway to modulate mitochondrial dynamics in Drosophila. ( 4-6).