EndoA/Endophilin-A creates docking stations for autophagic proteins at synapses

Area of Science:

• Neuroscience
• Cell Biology
• Biochemistry

Background:

• Synapses have high metabolic demands and require local protein quality control.
• Neurons are post-mitotic, necessitating long-term synaptic maintenance.
• Endophilin-A (EndoA) was previously known for its role in endocytosis.

Purpose of the Study:

• To investigate the role of macroautophagy/autophagy in synaptic protein quality control.
• To identify regulators of synaptic autophagy.
• To explore the link between Endophilin-A, LRRK2, and synaptic autophagy.

Main Methods:

• Investigated macroautophagy/autophagy in synapses.
• Examined the role of Endophilin-A (EndoA) in synaptic function.
• Studied the effect of LRRK2 kinase activity on EndoA phosphorylation and autophagy.
• Performed in vitro membrane curvature assays.

Main Results:

• Macroautophagy/autophagy is a local process at synapses, regulated by synapse-enriched Endophilin-A (EndoA).
• Metabolic and neuronal stimulation induce synaptic autophagy.
• Phosphorylation of EndoA by LRRK2 is essential for promoting synaptic autophagy.
• Phosphorylated EndoA induces membrane curvature and recruits Atg3, facilitating autophagy.

Conclusions:

• A synapse-enriched autophagy pathway controlled by EndoA exists.
• This pathway is regulated by LRRK2-mediated phosphorylation of EndoA.
• Dysregulation of this synaptic autophagy branch may contribute to Parkinson disease pathogenesis.