The Arabidopsis DJ-1a protein confers stress protection through cytosolic SOD activation.
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.
Xu
Xiang Ming
XM
Centre for Organelle Research, Faculty of Science and Technology, University of Stavanger, 4036 Stavanger, Norway.
Lin
Hong
H
Maple
Jodi
J
Björkblom
Benny
B
Alves
Guido
G
Larsen
Jan Petter
JP
Møller
Simon Geir
SG
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
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