Research On The Function Of MiR-26a In The Neuronal Morphogenesis

Objective: To investigate the function and molecular mechanism of miR-26a in thedevelopment of neurons.Methods:1.Detect the expression of miR-26a in Neural stem cells and Neurons through relativequantitative real-time PCR.2.Analysis the morphology of Nerons by immunofluorescencestaining and laser scanning confocal microscope.3.Explored predictive targets of miR-26athrough the TargetScan bioinformatics algorithm.4.Investigate the function of miR-26a andPTEN through overexpression(OE) and knockdown(KD), and ensure their expression by relativequantitative real-time PCR and western blot separately.Results:1.miR-26a is high expressed in mature neurons. real-time RT-PCR analysis wasindividually performed to characterize its expression. The level of miR-26a is higher in neuronsthan in NSCs. The expression of miR-26a in neurons was markedly increased by3.4-fold ofcontrol for NSCs.2.Expression of miR-26a progressively promotes the growth of neurite. Withthe upregulation of miR-26a, the neurite morphology significantly changed. Morphometricanalysis revealed that miR-26a transfected neurons had more neurite numbers and the averagetotal length was greater than that of its control miRNA transfected neurons.3.PTEN is a directtarget of miR-26a in neurons. Explored predictive targets of miR-26a through the TargetScanbioinformatics algorithm. Result revealed that3’-UTR of PTEN has three potential binding siteswhich are highly conserved evolutionarily. The luciferase report gene assay also confirm thatPTEN is a direct target of miR-26a.4.PTEN mediated the effect of miR-26a on the neurriteoutgrowth. The result showed that neurons transfected with PTEN generated an opposite result asneurons transfected with miR-26a. The growth of neurite was largely suppressed. In contrast,transfection of shRNA of PTEN enhanced the neurite outgrowth, the number and distribution ofneurites was significantly enlarged.Conclusion: miR-26a could regulate neurite outgrowth via repression PTEN expression.Overexpression miR-26a could induce the growth of neurite, this is beneficial to the function ofimpaired neurons. PTEN is the direct target of miR-26a and it can mediate the function ofmiR-26a in Neurons. This discovery of miR-26a might useful to the patients with Alzheimer’s disease (AD).