Basal mitophagy is widespread in Drosophila but minimally affected by loss of Pink1 or parkin

Parkinson’s disease factors, PINK1 and parkin, are strongly implicated in stress-induced mitophagy in vitro, but little is known about their impact on basal mitophagyin vivo. We generated transgenicDrosophilaexpressing fluorescent mitophagy reporters to evaluate the impact ofPink1/parkinmutations on basal mitophagy under physiological conditions. We find that mitophagy is readily detectable and abundant in many tissues including Parkinson’s disease relevant dopaminergic neurons. However, we did not detect mitolysosomes in flight muscle. Surprisingly, inPink1orparkinnull flies we did not observe any substantial impact on basal mitophagy. As these flies exhibit locomotor defects and dopaminergic neuron loss, our findings raise questions about current assumptions of the pathogenic mechanism associated with the PINK1/Parkin pathway. Our findings provide evidence that Pink1 and parkin are not essential for bulk basal mitophagy inDrosophila. They also emphasize that mechanisms underpinning basal mitophagy remain largely obscure.SummaryPINK1/parkin are key mediators of stress-induced mitophagyin vitrobut their impact on basal mitophagyin vivois unclear. NovelDrosophilareporters lines reveal abundant mitophagy in many tissues including dopaminergic neurons but is unaffected by loss of PINK1/parkin.