Cocaine-regulated microRNA miR-124 controls poly (ADP-ribose) polymerase-1 expression in neuronal cells

• Published in: Scientific reports 2020-07, Vol.10 (1), p.11197, Article 11197
• Main Authors: Dash, Sabyasachi, Balasubramaniam, Muthukumar, Martínez-Rivera, Freddyson J., Godino, Arthur, Peck, Emily G., Patnaik, Srinivas, Suar, Mrutyunjay, Calipari, Erin S., Nestler, Eric J., Villalta, Fernando, Dash, Chandravanu, Pandhare, Jui
• Format: Article
• Language: English
• Subjects: 3' Untranslated regions; 3' Untranslated Regions - genetics; 631/337/384/331; 631/378; 631/378/340; 631/378/87; 631/45; Adenosine diphosphate; Animals; Binding sites; Binding Sites - genetics; Cell culture; Cell Line, Tumor; Cocaine; Cocaine - pharmacology; Dopamine receptors; Dopaminergic Neurons - drug effects; Dopaminergic Neurons - metabolism; Down-Regulation - drug effects; Gene Knockdown Techniques; Humanities and Social Sciences; Humans; Injections, Intraperitoneal; Male; Mice; MicroRNAs; MicroRNAs - genetics; MicroRNAs - metabolism; miRNA; Models, Animal; multidisciplinary; Mutation; Nucleus accumbens; Nucleus Accumbens - cytology; Nucleus Accumbens - drug effects; Nucleus Accumbens - metabolism; PARP-1 protein; Place preference conditioning; Poly (ADP-Ribose) Polymerase-1 - genetics; Poly(ADP-ribose) polymerase; Post-transcription; Reinforcement; Ribose; Science; Science (multidisciplinary); Titration
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-68144-6

MiR-124 is a highly expressed miRNA in the brain and regulates genes involved in neuronal function. We report that miR-124 post-transcriptionally regulates PARP-1. We have identified a highly conserved binding site of miR-124 in the 3′-untranslated region (3′UTR) of Parp-1 mRNA. We demonstrate that miR-124 directly binds to the Parp-1 3′UTR and mutations in the seed sequences abrogate binding between the two RNA molecules. Luciferase reporter assay revealed that miR-124 post-transcriptionally regulates Parp-1 3′UTR activity in a dopaminergic neuronal cell model. Interestingly, the binding region of miR-124 in Parp-1 3′UTR overlapped with the target sequence of miR-125b, another post-transcriptional regulator of Parp-1 . Our results from titration and pull-down studies revealed that miR-124 binds to Parp-1 3′UTR with greater affinity and confers a dominant post-transcriptional inhibition compared to miR-125b. Interestingly, acute or chronic cocaine exposure downregulated miR-124 levels concomitant with upregulation of PARP-1 protein in dopaminergic-like neuronal cells in culture. Levels of miR-124 were also downregulated upon acute or chronic cocaine exposure in the mouse nucleus accumbens (NAc)-a key reward region of brain. Time-course studies revealed that cocaine treatment persistently downregulated miR-124 in NAc. Consistent with this finding, miR-124 expression was also significantly reduced in the NAc of animals conditioned for cocaine place preference. Collectively, these studies identify Parp-1 as a direct target of miR-124 in neuronal cells, establish miR-124 as a cocaine-regulated miRNA in the mouse NAc, and highlight a novel pathway underlying the molecular effects of cocaine.