Mutations in Auxilin cause parkinsonism via impaired clathrin-mediated trafficking at the Golgi apparatus and synapse

Roosen, DA; Landeck, N; Conti, M; Smith, N; Saez-Atienzar, S; Ding, J; Beilina, A; Kumaran, R; Kaganovich, A; Hoffmann, JD; Williamson, CD; Gershlick, DC; Bonet-Ponce, L; Sampieri, L; Bleck, CKE; Liu, C; Bonifacino, JS; Li, Y; Lewis, PA; Cookson, MR

Abstract

Parkinson’s disease (PD) is a common neurodegenerative motor disorder characterized in part by neuropathological lesions in the nigrostriatal pathway. While most cases of PD are sporadic in nature, several inherited monogenic syndromes exist that overlap clinically and pathologically with sporadic PD. Of these, loss of function mutations in DNAJC6, which encodes the protein Auxilin, cause an aggressive form of juvenile onset PD. Auxilin and its homologues are known to play a role in clathrin-mediated trafficking, which is crucial for cellular function in all eukaryotes and plays a specialized role in synaptic transmission in higher organisms. Auxilin is the major neuronal uncoating protein for clathrin-coated vesicles required for delivery of cargo from the plasma membrane and trans-Golgi network to intracellular destinations. However, how mutations in Auxilin cause PD is currently not understood. To address this problem, we generated a novel mouse model carrying an endogenous pathogenic Auxilin mutation. When bred to homozygosity, this mutation induced neurological phenotypes that phenocopy clinical features observed in patients, including motor impairments reminiscent of bradykinesia and gait problems. Mapping the interactome of Auxilin confirmed clathrin and synaptic clathrin adaptor protein interactions and also identified novel Golgi-resident interactors. Critically, all tested pathogenic mutations in Auxilin retained clathrin adaptor protein binding but lost interaction with clathrin itself. These observations describe a mechanism by which impaired clathrin-mediated trafficking in R857G Auxilin mice, both at the Golgi and the synapse, results in neuropathological lesions in the nigrostriatal pathway. Collectively, these results provide novel insights for PD pathogenesis in Auxilin mutation carriers, reinforcing a key role for clathrin-mediated trafficking in PD, and expand our understanding of the cellular function of Auxilin.

Citation

Roosen, D., Landeck, N., Conti, M., Smith, N., Saez-Atienzar, S., Ding, J., …Cookson, M. (2019). Mutations in Auxilin cause parkinsonism via impaired clathrin-mediated trafficking at the Golgi apparatus and synapse

• Publication Date: Nov 7, 2019
• Deposit Date: Aug 17, 2020
• Book Title: Mutations in Auxilin cause parkinsonism via impaired clathrin-mediated trafficking at the Golgi apparatus and synapse
• DOI: https://doi.org/10.1101/830802
• Public URL: https://rvc-repository.worktribe.com/output/1379805