Most Dana, Leiter Courtney, Blednov Yuri A, Harris R Adron, Mayfield R Dayne
Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, TX, USA.
Institute for Neuroscience (INS), University of Texas at Austin, Austin, TX, USA.
Neuropsychopharmacology. 2016 Jan;41(2):538-48. doi: 10.1038/npp.2015.179. Epub 2015 Jun 24.
Local translation of mRNAs in the synapse has a major role in synaptic structure and function. Chronic alcohol use causes persistent changes in synaptic mRNA expression, possibly mediated by microRNAs localized in the synapse. We profiled the transcriptome of synaptoneurosomes (SN) obtained from the amygdala of mice that consumed 20% ethanol (alcohol) in a 30-day continuous two-bottle choice test to identify the microRNAs that target alcohol-induced mRNAs. SN are membrane vesicles containing pre- and post-synaptic compartments of neurons and astroglia and are a unique model for studying the synaptic transcriptome. We previously showed that chronic alcohol regulates mRNA expression in a coordinated manner. Here, we examine microRNAs and mRNAs from the same samples to define alcohol-responsive synaptic microRNAs and their predicted interactions with targeted mRNAs. The aim of the study was to identify the microRNA-mRNA synaptic interactions that are altered by alcohol. This was accomplished by comparing the effect of alcohol in SN and total homogenate preparations from the same samples. We used a combination of unbiased bioinformatic methods (differential expression, correlation, co-expression, microRNA-mRNA target prediction, co-targeting, and cell type-specific analyses) to identify key alcohol-sensitive microRNAs. Prediction analysis showed that a subset of alcohol-responsive microRNAs was predicted to target many alcohol-responsive mRNAs, providing a bidirectional analysis for identifying microRNA-mRNA interactions. We found microRNAs and mRNAs with overlapping patterns of expression that correlated with alcohol consumption. Cell type-specific analysis revealed that a significant number of alcohol-responsive mRNAs and microRNAs were unique to glutamate neurons and were predicted to target each other. Chronic alcohol consumption appears to perturb the coordinated microRNA regulation of mRNAs in SN, a mechanism that may explain the aberrations in synaptic plasticity affecting the alcoholic brain.
突触中mRNA的局部翻译在突触结构和功能中起主要作用。长期饮酒会导致突触mRNA表达的持续变化，这可能由定位于突触的微小RNA介导。我们对从在30天连续双瓶选择试验中摄入20%乙醇（酒精）的小鼠杏仁核中获得的突触神经小体（SN）的转录组进行了分析，以鉴定靶向酒精诱导mRNA的微小RNA。SN是包含神经元和星形胶质细胞突触前和突触后成分的膜囊泡，是研究突触转录组的独特模型。我们之前表明，长期饮酒以协调的方式调节mRNA表达。在这里，我们检查来自相同样本的微小RNA和mRNA，以确定对酒精有反应的突触微小RNA及其与靶向mRNA的预测相互作用。该研究的目的是鉴定因酒精而改变的微小RNA-mRNA突触相互作用。这是通过比较酒精对相同样本的SN和总匀浆制剂的影响来实现的。我们使用了多种无偏生物信息学方法（差异表达、相关性、共表达、微小RNA-mRNA靶标预测、共同靶向和细胞类型特异性分析）来鉴定关键的酒精敏感微小RNA。预测分析表明，一部分对酒精有反应的微小RNA被预测靶向许多对酒精有反应的mRNA，为鉴定微小RNA-mRNA相互作用提供了双向分析。我们发现了与酒精消耗相关的具有重叠表达模式的微小RNA和mRNA。细胞类型特异性分析表明，大量对酒精有反应的mRNA和微小RNA是谷氨酸能神经元特有的，并且被预测相互靶向。长期饮酒似乎扰乱了SN中mRNA的协调微小RNA调节，这一机制可能解释了影响酒精性脑的突触可塑性异常。
