Human R1441C LRRK2 regulates the synaptic vesicle proteome and phosphoproteome in a Drosophila model of Parkinson’s disease

Islam, S. et al. (2016) Human R1441C LRRK2 regulates the synaptic vesicle proteome and phosphoproteome in a Drosophila model of Parkinson’s disease. Human Molecular Genetics, 25(24), pp. 5365-5382. (doi: 10.1093/hmg/ddw352) (PMID:27794539)

Abstract

Mutations in leucine-rich repeat kinase 2 (LRRK2) cause late-onset, autosomal dominant familial Parkinson’s disease (PD) and variation at the LRRK2 locus contributes to the risk for idiopathic PD. LRRK2 can function as a protein kinase and mutations lead to increased kinase activity. To elucidate the pathophysiological mechanism of the R1441C mutation in the GTPase domain of LRRK2, we expressed human wild-type or R1441C LRRK2 in dopaminergic neurons of Drosophila and observe reduced locomotor activity, impaired survival and an age-dependent degeneration of dopaminergic neurons thereby creating a new PD-like model. To explore the function of LRRK2 variants in vivo, we performed mass spectrometry and quantified 3,616 proteins in the fly brain. We identify several differentially-expressed cytoskeletal, mitochondrial and synaptic vesicle proteins (SV), including synaptotagmin-1, syntaxin-1A and Rab3, in the brain of this LRRK2 fly model. In addition, a global phosphoproteome analysis reveals the enhanced phosphorylation of several SV proteins, including synaptojanin-1 (pThr1131) and the microtubule-associated protein futsch (pSer4106) in the brain of R1441C hLRRK2 flies. The direct phosphorylation of human synaptojanin-1 by R1441C hLRRK2 could further be confirmed by in vitro kinase assays. A protein-protein interaction screen in fly brain confirms that LRRK2 robustly interacts with numerous SV proteins, including synaptojanin-1 and EndophilinA. Our proteomic, phosphoproteomic and interactome study in the Drosophila brain provides a systematic analyses of R1441C hLRRK2-induced pathobiological mechanisms in this model. We demonstrate for the first time that the R1441C mutation located within the LRRK2 GTPase domain induces the enhanced phosphorylation of SV proteins in the brain.

• Item Type: Articles
• Additional Information: This work was supported by the DFG (Excellence Cluster Cardio-Pulmonary System), the LOEWE Center for Cell and Gene Therapy, the German Center for Cardiovascular Research, the Universities of Giessen and Marburg Lung Center, the National Institutes of Health (R01 NS091719 to DJM) and the Swiss National Science Foundation (Grant No. 31003A_144063 to DJM). The authors thank Milka Uhlirova for Drosophila stock maintance. MdSI was recipient of an ESR fellowship receiving funding for this project by European Community’s Framework Programme (FP7) under grant agreement number TRANSPOL – 264399. WJ initiated this project while he was recipient of an ITN-fellowship INTCHEM.
• Keywords: Synaptic vesicle proteome, Parkinson’s disease, Drosophila.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Jacob, Dr Wright
• Authors: Islam, S., Nolte, H., Jacob, W., Ziegler, A. B., Pütz, S., Grosjean, Y., Szczepanowska, K., Trifunovic, A., Braun, T., Heumann, H., Heumann, R., Hovemann, B., Moore, D. J., and Krüger, M.
• Subjects: Q Science > QL Zoology; Q Science > QP Physiology; R Medicine > R Medicine (General)
• College/School: College of Medical Veterinary and Life Sciences > School of Cancer Sciences
• Journal Name: Human Molecular Genetics
• Journal Abbr.: Hum. Mol. Genet.
• Publisher: Oxford University Press
• ISSN: 0964-6906
• ISSN (Online): 1460-2083
• Published Online: 29 October 2016