title: Convergence of miRNA expression profiling, α-synuclein interacton and GWAS in Parkinson's disease.
abstract: miRNAs were recently implicated in the pathogenesis of numerous diseases, including neurological disorders such as Parkinson's disease (PD). miRNAs are abundant in the nervous system, essential for efficient brain function and play important roles in neuronal patterning and cell specification. To further investigate their involvement in the etiology of PD, we conducted miRNA expression profiling in peripheral blood mononuclear cells (PBMCs) of 19 patients and 13 controls using microarrays. We found 18 miRNAs differentially expressed, and pathway analysis of 662 predicted target genes of 11 of these miRNAs revealed an over-representation in pathways previously linked to PD as well as novel pathways. To narrow down the genes for further investigations, we undertook a parallel approach using chromatin immunoprecipitation-sequencing (ChIP-seq) analysis to uncover genome-wide interactions of α-synuclein, a molecule with a central role in both monogenic and idiopathic PD. Convergence of ChIP-seq and miRNomics data highlighted the glycosphingolipid biosynthesis and the ubiquitin proteasome system as key players in PD. We then tested the association of target genes belonging to these pathways with PD risk, and identified nine SNPs in USP37 consistently associated with PD susceptibility in three genome-wide association studies (GWAS) datasets (0.46≤OR≤0.63) and highly significant in the meta-dataset (3.36×10⁻⁴<p <1.94×10⁻³). A SNP in ST8SIA4 was also highly associated with PD (p = 6.15×10⁻³) in the meta-dataset. These findings suggest that several miRNAs may act as regulators of both known and novel biological processes leading to idiopathic PD.
authors: Neurological Clinical Research Unit, Instituto de Medicina Molecular, Lisboa, Portugal.
authors: Madalena
authors: M
authors: Martins
authors: Alexandra
authors: A
authors: Rosa
authors: Leonor C
authors: LC
authors: Guedes
authors: Benedita V
authors: BV
authors: Fonseca
authors: Kristina
authors: K
authors: Gotovac
authors: Sara
authors: S
authors: Violante
authors: Tiago
authors: T
authors: Mestre
authors: Miguel
authors: M
authors: Coelho
authors: Mário M
authors: MM
authors: Rosa
authors: Eden R
authors: ER
authors: Martin
authors: Jeffery M
authors: JM
authors: Vance
authors: Tiago F
authors: TF
authors: Outeiro
authors: Liyong
authors: L
authors: Wang
authors: Fran
authors: F
authors: Borovecki
authors: Joaquim J
authors: JJ
authors: Ferreira
authors: Sofia A
authors: SA
authors: Oliveira
mesh_terms: D000368:Aged; D005260:Female; D020869:Gene Expression Profiling; D020022:Genetic Predisposition to Disease / Q000235:genetics; D055106:Genome-Wide Association Study; D023281:Genomics; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D020411:Oligonucleotide Array Sequence Analysis; D010300:Parkinson Disease / Q000235:genetics* / Q000378:metabolism; D018511:Systems Integration; D051844:alpha-Synuclein / Q000378:metabolism*
chemical_list: D035683:MicroRNAs; D051844:alpha-Synuclein