Expression of DJ-1 in Neurodegenerative Disorders

In 2003, autosomal recessive loss-of-function mutations were identified in PARK7 gene that caused early-onset Parkinson's disease (PD). The PARK7 gene encodes a conserved protein termed DJ-1. DJ-1 is a ubiquitous protein, and within the brain, it is present in the nucleus and cytoplasm of both neuronal and glial cells. DJ-1 is a multifunctional protein, and numerous studies have ascribed various roles, including antioxidative properties, chaperone function, protease activities, mitochondrial functions and regulation of transcription to the protein. The DJ-1 protein undergoes oxidation and post-translational modifications that are important for its function. Not only is DJ-1 linked to familial PD, but it is also associated with the pathogenic mechanisms of sporadic PD and other neurodegenerative disorders where oxidative stress is implicated. In this chapter we provide an overview on the expression of DJ-1 mRNA and protein in different neurodegenerative disorders and discuss some of its main functions together with DJ-1's potential for neuroprotection.