Parkin Deficiency Delays Motor Decline and Disease Manifestation in a Mouse Model of Synucleinopathy Margot Fournier1,2,3, Je´ re´ mie Vitte1,2,3, Je´ roˆ me Garrigue1,2,3, Dominique Langui1,2,3, Jean-Philippe Dullin1,2,3, Fran c¸oise Saurini4,5, Naı¨ma Hanoun4,5, Fernando Perez-Diaz1,2,3, Fabien Cornilleau1,2,3, Chantal Joubert1,2,3, He´ ctor Ardila-Osorio1,2,3, Sabine Traver1,2,3, Rene´ Duchateau 6 , Ce´ cile Goujet-Zalc6, Katerina Paleologou 7 , Hilal A. Lashuel7, Christian Haass8, Charles Duyckaerts1,2,3, Charles Cohen- Salmon 9 , Philipp J. Kahle10, Michel Hamon4,5, Alexis Brice1,2,3,11, Olga Corti1,2,3* 1 Universite´ Pierre et Marie Curie-Paris 6, CRICM (Centre de Recherche de l9Institut du Cerveau et de la Moelle e´pinie`re), UMR-S975, Paris, France, 2 Inserm (Institut National de la Sante´ et de la Recherche Me´dicale), U975, Paris, France, 3 CNRS (Centre National de la Recherche Scientifique), UMR 7225, Paris, France, 4 Universite´ Pierre et Marie Curie-Paris 6, CRPN (Centre de Recherche en Psychiatrie et Neurosciences), UMR-S894, Paris, France, 5 Inserm, U894, Paris, France, 6 CNRS, SEAT (Service d’Expe´rimentation Animale et de Transgene`se), Villejuif, France, 7 Laboratory of Molecular Neurobiology and Neuroproteomics, EPFL (Ecole Polytechnique Fe´de´rale de Lausanne), Lausanne, Switzerland, 8 Department of Biochemistry, Adolf-Butenandt-Institut, Ludwig-Maximilians University, Munich, Germany, 9 Inserm, U676, Paris, France, 10 Department of Neurodegeneration, Hertie Institute for Clinical Brain Research, Tu¨ bingen, Germany, 11 Department of Genetics and Cytogenetics, AP-HP (Assistance Publique Hoˆ pitaux de Paris), Groupe Hospitalier Pitie´-Salpeˆtrie`re, Paris, France Abstract In synucleinopathies, including Parkinson’s disease, partially ubiquitylated a-synuclein species phosphorylated on serine 129 (PS129-a-synuclein) accumulate abnormally. Parkin, an ubiquitin-protein ligase that is dysfunctional in autosomal recessive parkinsonism, protects against a-synuclein-mediated toxicity in various models. We analyzed the effects of Parkin deficiency in a mouse model of synucleinopathy to explore the possibility that Parkin and a-synuclein act in the same biochemical pathway. Whether or not Parkin was present, these mice developed an age-dependent neurodegenerative disorder preceded by a progressive decline in performance in tasks predictive of sensorimotor dysfunction. The symptoms were accompanied by the deposition of PS129-a-synuclein but not PS87-a-synuclein in neuronal cell bodies and neuritic processes throughout the brainstem and the spinal cord; activation of caspase 9 was observed in 5% of the PS129-a- synuclein-positive neurons. As in Lewy bodies, ubiquitin-immunoreactivity, albeit less abundant, was invariably co-localized with PS129-a-synuclein. During late disease stages, the disease-specific neuropathological features revealed by ubiquitin- and PS129-a-synuclein-specific antibodies were similar in mice with or without Parkin. However, the proportion of PS129-a- synuclein-immunoreactive neuronal cell bodies and neurites co-stained for ubiquitin was lower in the absence than in the presence of Parkin, suggesting less advanced synucleinopathy. Moreover, sensorimotor impairment and manifestation of the neurodegenerative phenotype due to overproduction of human a-synuclein were significantly delayed in Parkin- deficient mice. These findings raise the possibility that effective compensatory mechanisms modulate the phenotypic expression of disease in parkin-related parkinsonism. Citation: Fournier M, Vitte J, Garrigue J, Langui D, Dullin J-P, et al. (2009) Parkin Deficiency Delays Motor Decline and Disease Manifestation in a Mouse Model of Synucleinopathy. PLoS ONE 4(8): e6629. doi:10.1371/journal.pone.0006629 Editor: Mark R. Cookson, National Institutes of Health, United States of America Received April 17, 2009; Accepted July 7, 2009; Published August 14, 2009 Copyright: 2009 Fournier et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: Margot Fournier was supported by the French Ministry of Research and the Fondation pour la Recherche Me´dicale. This project was supported by Institut National de la Sante´ et de la Recherche Me´dicale, Abnormal proteins in the pathogenesis of neurodegenerative disorders (APOPIS, an integrated project funded by the EU under the Sixth Framework Programme; Priority: Life Science for Health, contract no. LSHM-CT-2003-503330), Fondation de France (2003 013 796), and Fe´de´ration pour la Recherche sur le Cerveau. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: olga.corti@upmc.fr Introduction a-Synuclein- and ubiquitin-immunoreactive protein inclusions in neuronal cell bodies and processes (Lewy bodies, LBs; Lewy neurites) or in glial cells are pathological markers of a subset of neurodegenerative diseases referred to as synucleinopathies; these diseases include Parkinson’s disease (PD), dementia with LBs and other LB diseases, and multiple system atrophy. Phosphorylation of serine 129 is a widespread a-synuclein modification in LBs, whereas serine 87, found to be constitutively phosphorylated in cell lines, is not modified in these inclusions [1,2]. A fraction of a- synuclein is covalently modified by one to three ubiquitin molecules in these inclusions [2–4]; there is biochemical evidence that a-synuclein phosphorylated on serine 129 (PS129-a-synuclein) is the major substrate for ubiquitylation [2]. Three rare missense mutations in the a-synuclein gene, SCNA, and more frequently duplications or triplications of genomic regions including SCNA are responsible for parkinsonism with autosomal dominant inheritance [5]. The severity of the phenotype correlates with the number of SCNA copies in patients with genomic multiplica- tions [6,7], and supernumerary SCNA alleles are associated with increased protein load in both the blood and brain of affected PLoS ONE | www.plosone.org 1 August 2009 | Volume 4 | Issue 8 | e6629