title: The Arabidopsis DJ-1a protein confers stress protection through cytosolic SOD activation.
abstract: Mutations in the DJ-1 gene (also known as PARK7) cause inherited Parkinson's disease, which is characterized by neuronal death. Although DJ-1 is thought to be an antioxidant protein, the underlying mechanism by which loss of DJ-1 function contributes to cell death is unclear. Human DJ-1 and its Arabidopsis thaliana homologue, AtDJ-1a, are evolutionarily conserved proteins, indicating a universal function. To gain further knowledge of the molecular features associated with DJ-1 dysfunction, we have characterized AtDJ-1a. We show that AtDJ-1a levels are responsive to stress treatment and that AtDJ-1a loss of function results in accelerated cell death in aging plants. By contrast, transgenic plants with elevated AtDJ-1a levels have increased protection against environmental stress conditions, such as strong light, H(2)O(2), methyl viologen and copper sulfate. We further identify superoxide dismutase 1 (SOD1) and glutathione peroxidase 2 (GPX2) as interaction partners of both AtDJ-1a and human DJ-1, and show that this interaction results in AtDJ-1a- and DJ-1-mediated cytosolic SOD1 activation in a copper-dependent fashion. Our data have highlighted a conserved molecular mechanism for DJ-1 and revealed a new protein player in the oxidative stress response of plants.
authors.affiliation: Centre for Organelle Research, Faculty of Science and Technology, University of Stavanger, 4036 Stavanger, Norway.
authors.forename: Xiang Ming
authors.initials: XM
authors.lastname: Xu
authors.forename: Hong
authors.initials: H
authors.lastname: Lin
authors.forename: Jodi
authors.initials: J
authors.lastname: Maple
authors.forename: Benny
authors.initials: B
authors.lastname: Björkblom
authors.forename: Guido
authors.initials: G
authors.lastname: Alves
authors.forename: Jan Petter
authors.initials: JP
authors.lastname: Larsen
authors.forename: Simon Geir
authors.initials: SG
authors.lastname: Møller
mesh_terms: D017209:Apoptosis / Q000235:genetics; D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D017124:Conserved Sequence; D019610:Cytoprotection; D003600:Cytosol / Q000378:metabolism; D004789:Enzyme Activation / Q000235:genetics; D005979:Glutathione Peroxidase / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics; D008027:Light / Q000009:adverse effects; D009154:Mutation / Q000235:genetics; D015513:Oncogene Proteins / Q000235:genetics; D018384:Oxidative Stress / Q000235:genetics; D010300:Parkinson Disease / Q000235:genetics; D030821:Plants, Genetically Modified; D011485:Protein Binding; D000071617:Protein Deglycase DJ-1; D013312:Stress, Physiological / Q000235:genetics; D013482:Superoxide Dismutase / Q000378:metabolism*; D000072105:Superoxide Dismutase-1; D019076:Transgenes / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; C552349:DJ-1a protein, Arabidopsis; D047908:Intracellular Signaling Peptides and Proteins; D015513:Oncogene Proteins; C000606290:SOD1 protein, human; C117436:GPX2 protein, human; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1; C105131:PARK7 protein, human; D000071617:Protein Deglycase DJ-1