Protein deglycase DJ-1, also known as Parkinson disease protein 7, is a protein which in humans is encoded by the PARK7 gene. [5]
The gene PARK7, also known as DJ-1, encodes a protein of the peptidase C56 family. The human gene PARK7 has 8 exons and locates at chromosome band 1p36.23. [5]
The human protein deglycase DJ-1 is 20 kDa in size and composed of 189 amino acids with seven β-strands and nine α-helices in total and is present as a dimer. [6] [7] [8] It belongs to the peptidase C56 family of proteins.
The protein structures of human protein DJ-1, Escherichia coli chaperone Hsp31, YhbO, and YajL and an Archaea protease are evolutionarily conserved. [9]
Under an oxidative condition, protein deglycase DJ-1 inhibits the aggregation of α-synuclein via its chaperone activity, [10] [11] thus functioning as a redox-sensitive chaperone and as a sensor for oxidative stress. Accordingly, DJ-1 apparently protects neurons against oxidative stress and cell death. [5] In parallel, protein DJ-1 acts as a positive regulator of androgen receptor-dependent transcription. DJ-1 is expressed in both the neural retina and retinal pigment epithelium of mammals, where it exerts a neuroprotective role against oxidative stress under both physiological and pathological conditions. [12] [13]
Pyrroloquinoline quinone (PQQ) has been shown to reduce the self-oxidation of the DJ-1 protein, an early step in the onset of some forms of Parkinson's disease. [14]
Functional DJ-1 protein has been shown to bind metals and protect against metal-induced cytotoxicity from copper and mercury. [15]
DJ-1/PARK7 and its bacterial homologs: Hsp31, YhbO, and YajL can repair methylglyoxal and glyoxal glycated nucleotides. [16] Guanine, either in the form of a free nucleotide or as a nucleotide incorporated into nucleic acid (DNA or RNA), if glycated, can be repaired by DJ-1/PARK7. [16] Deglycase-deficient bacterial mutants with reduced ability to repair glycated bases in DNA show strong mutator phenotypes. [16]
DJ-1 is a DNA damage response protein that is recruited to sites of DNA damage where it participates in the repair of DNA double-strand breaks through the processes of non-homologous end joining and homologous recombination. [17] Evidence for a linkage between DNA damage and Parkinson's disease has been reported for decades. [17] Recently evidence has been presented that defective DNA repair is linked specifically to DJ-1 mutation, and thus DJ-1 mutation likely contributes to Parkinson's disease pathogenesis. [17]
Defects in this gene are the cause of autosomal recessive early-onset Parkinson's disease 7. [5] [18]
PARK7 has been shown to interact with:
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ignored (help)This article incorporates text from the United States National Library of Medicine, which is in the public domain.