EndophilinA-dependent coupling between activity-induced calcium influx and synaptic autophagy is disrupted by a Parkinson-risk mutation

Neuron. 2023 Feb 15;S0896-6273(23)00079-X. doi: 10.1016/j.neuron.2023.02.001. Online ahead of print.

Abstract

Neuronal activity causes use-dependent decline in protein function. However, it is unclear how this is coupled to local quality control mechanisms. We show in Drosophila that the endocytic protein Endophilin-A (EndoA) connects activity-induced calcium influx to synaptic autophagy and neuronal survival in a Parkinson disease-relevant fashion. Mutations in the disordered loop, including a Parkinson disease-risk mutation, render EndoA insensitive to neuronal stimulation and affect protein dynamics: when EndoA is more flexible, its mobility in membrane nanodomains increases, making it available for autophagosome formation. Conversely, when EndoA is more rigid, its mobility reduces, blocking stimulation-induced autophagy. Balanced stimulation-induced autophagy is required for dopagminergic neuron survival, and a variant in the human ENDOA1 disordered loop conferring risk to Parkinson disease also blocks nanodomain protein mobility and autophagy both in vivo and in human-induced dopaminergic neurons. Thus, we reveal a mechanism that neurons use to connect neuronal activity to local autophagy and that is critical for neuronal survival.

Keywords: Ca(2+) influx; Parkinson disease; endophilinA; neuronal activity; synaptic autophagy.