%0 Journal Article
%T MicroRNAs targeting Nicastrin regulate A¦Â production and are affected by target site polymorphisms
%A Charlotte Delay
%A V¨¦ronique Dorval
%A S¨¦bastien S. H¨¦bert
%J Frontiers in Molecular Neuroscience
%D 2014
%I Frontiers Media
%R 10.3389/fnmol.2014.00067
%X Despite the growing number of genome-wide association studies, the involvement of polymorphisms in microRNA target sites (polymiRTS) in Alzheimer¡¯s disease (AD) remains poorly investigated. Recently, we have shown that AD-associated single-nucleotide polymorphisms (SNPs) present in the 3¡ä untranslated region (3¡äUTR) of amyloid precursor protein (APP) could directly affect miRNA function. In theory, loss of microRNA (miRNA) function could lead to risk for AD by increasing APP expression and A¦Â peptide production. In this study, we tested the hypothesis that Nicastrin, a ¦Ã-secretase subunit involved in A¦Â generation, could be regulated by miRNAs, and consequently affected by 3¡äUTR polymorphisms. Bioinformatic analysis identified 22 putative miRNA binding sites located in or near Nicastrin 3¡äUTR polymorphisms. From these miRNA candidates, six were previously shown to be expressed in human brain. We identified miR-24, miR-186, and miR-455 as regulators of Nicastrin expression, both in vitro and under physiological conditions in human cells, which resulted in altered A¦Â secretion. Using luciferase-based assays, we further demonstrated that rs113810300 and rs141849450 SNPs affected miRNA-mediated repression of Nicastrin. Notably, rs141849450 completely abolished the miR-455-mediated repression of Nicastrin. Finally, the rs141849450 variant was identified in 1 out of 511 AD cases but not in 631 controls. These observations set the stage for future studies exploring the role of miRNAs and 3¡äUTR polymorphisms in AD.
%K Alzheimer¡¯s disease
%K Nicastrin
%K microRNA
%K single-nucleotide polymorphism
%K miR-186
%K miR-455
%U http://www.frontiersin.org/Journal/10.3389/fnmol.2014.00067/abstract