Bioinformatic analysis of microRNA expression in Parkinson's disease.

Parkinson's disease (PD) is a type of movement disorder caused by loss of dopamine-producing neurons in the midbrain. In order to identify the synergistic microRNA (miRNA) pattern in PD, miRNA and mRNA double expression profiles of PD were downloaded. Differentially expressed miRNA and mRNA were identified [P<0.01, following false discovery rate (FDR) correction]. A cumulative hypergeometric distribution test was then performed to identify synergistic miRNAs (P<0.01, following FDR correction). Gene ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotations were performed to analyze the miRNA regulatory target genes. Subsequently, a synergistic miRNA network was constructed and miRNAs exhibiting a high degree were identified. In total, 200 differentially expressed miRNA and 2,966 differentially expressed mRNA were identified. In addition, 1,502 synergistic miRNA interactions were identified, and miRNAs regulated 304 target genes in total. The GO and KEGG analysis demonstrated that these target genes were enriched in biosynthetic and cellular biosynthetic processes, the assembly of cellular components in morphogenesis, mitogen-activated protein kinase signaling, myometrial relaxation and contraction pathways as well as calcium regulation. The miRNA network demonstrated that miR-627, miR-634, miR-514, miR-563 and miR-613 had a high degree. miRNA with a high degree may be associated with the pathogenesis of PD and, therefore, may assist in the diagnosis and therapy of PD.