Microrna-Reacting Pseudogenes Control Cholinergic Signaling In Brain Neurons

• Published in: European neuropsychopharmacology Vol. 27; p. S417
• Main Authors: Soreq, Hermona, Simchovitz, Alon, Barbash, Shahar, Hanin, Geula, Roitman, Michal
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 2017
• ISSN: 0924-977X; 1873-7862
• DOI: 10.1016/j.euroneuro.2016.09.464

Cholinergic signaling is controlled, among other elements by microRNA (miR) suppressors of the multiple coding cholinergic mRNA transcripts, and is impaired by single nucleotide poly-morphisms (SNPs) interrupting this suppression [1,2]. We have recently discovered that the selected group of non-coding pseudogenes(PSGs) carrying miR recognition elements (PSG+MRE), but not the great majority of PSGs devoid of MREs compete with brain-expressed genes on the available miR regulators, and that SNPs surrounding these coding genes tend to be more abundant in DNA from patients with psychiatric diseases compared to healthy controls. To focus on the relevance of this phenomenon to the cholinergic signaling pathway, we tested if brain miRs targeting cholinergic-related transcripts are subject to PSG+MRE surveillance. Here, we report transfection-mediated over-expression of PSG+MRE and GapmeR-directed suppression of selected human- and brain-specific cholinergic transcripts sharing MREs with them in cultured human cells, demonstrating bi-directional modulation of the interaction of these transcripts with miRs. Specifically, a dual luciferase reporter assay established in 293T-HEK cells showed that over-expression of PSG+MRE potentiated the expression levels of coding transcripts for the acetylcholine packaging Vesicular Acetylcholine Transferase (VACHT) and the acetylcholine hydrolyzing butyrylcholinesterase (BCHE), with whom they share MREs. Reciprocally, we found that selective GapmeR suppression of the acetylcholine hydrolyzing Acetylcholinesterase (ACHE) co-suppressed those PSG+MRE sharing MREs with AChE in SHSY-5Y human neuroblastoma cells. A notable example includes PSG interference with miR-608/AChE interaction, impairment of which exacerbates anxiety in healthy adults while potentiating stress-induced prefrontal activity in fMRI tests [3]. Furthermore, the extent of suppression of these PSG+MRE was proportional to the number of shared MREs between the coding transcripts and the corresponding PSG+MRE, providing a yet stronger indication for the suggested regulatory mechanism. Our findings indicate functional roles of PSGs+MRE in cholinergic functioning, with potential impact on brain health and mental disease.