PARIS (ZNF746) repression of PGC-1α contributes to neurodegeneration in Parkinson's disease

A hallmark of Parkinson's disease (PD) is the preferential loss of substantia nigra dopamine neurons. Here, we identify a new parkin interacting substrate, PARIS (ZNF746), whose levels are regulated by the ubiquitin Proteasome system via binding to and ubiquitination by the E3 ubiquitin Ligase, parkin. PARIS is a KRAB and Zinc Finger Protein that accumulates in models of parkin inactivation and in human PD brain. PARIS represses the expression of the transcriptional coactivator, PGC-1α and the PGC-1α target gene, NRF-1 by binding to Insulin response sequences in the PGC-1α promoter. Conditional knockout of parkin in adult Animals leads to progressive loss of dopamine (DA) neurons in a PARIS-dependent manner. Moreover, overexpression of PARIS leads to the selective loss of DA neurons in the substantia nigra, and this is reversed by either parkin or PGC-1α coexpression. The identification of PARIS provides a molecular mechanism for neurodegeneration due to parkin inactivation.