Integrative genome-wide analysis of dopaminergic neuron-specific PARIS expression in Drosophila dissects recognition of multiple PPAR-γ associated gene regulation.

The transcriptional repressor called parkin interacting substrate (PARIS; ZNF746) was initially identified as a novel co-substrate of parkin and PINK1 that leads to Parkinson's disease (PD) by disrupting mitochondrial biogenesis through peroxisome proliferator-activated receptor gamma (PPARγ) coactivator -1α (PGC-1α) suppression. Since its initial discovery, growing evidence has linked PARIS to defective mitochondrial biogenesis observed in PD pathogenesis. Yet, dopaminergic (DA) neuron-specific mechanistic underpinnings and genome-wide PARIS binding landscape has not been explored. We employed conditional translating ribosome affinity purification (TRAP) followed by RNA sequencing (TRAP-seq) for transcriptome profiling of DA neurons in transgenic Drosophila lines expressing human PARIS wild type (WT) or mutant (C571A). We also generated genome-wide maps of PARIS occupancy using ChIP-seq in human SH-SY5Y cells. The results demonstrated that PPARγ functions as a master regulator of PARIS-induced molecular changes at the transcriptome level, confirming that PARIS acts primarily on PGC-1α to lead to neurodegeneration in PD. Moreover, we identified that PARIS actively modulates expression of PPARγ target genes by physically binding to the promoter regions. Together, our work revealed how PARIS drives adverse effects on modulation of PPAR-γ associated gene clusters in DA neurons.