Dicer1缺失对小鼠早期神经发育的影响

Effect of Dicer1 ablation on early neurodevelopment of mice

目的利用Dicer1条件敲除小鼠,通过RNA-seq技术在转录组水平分析microRNAs(miRNAs)对哺乳动物大脑早期发育的影响。方法构建D6-Cre-Dicer1条件敲除小鼠,实验分为对照组(Ctrl)和条件敲除组(cKO)。苏木精-伊红和免疫荧光染色比较敲除前后组织形态差异;选取E14.5 D6-Cre介导的Dicer1条件性敲除的小鼠背侧皮质,提取总RNA,利用RNA-seq技术分析Dicer1敲除前后转录水平差异。结果与对照组相比,条件敲除组1个月左右致死,P3时皮层神经元发育异常,皮层和海马结构部分缺失;通过RNA-seq分析,共筛选出差异表达基因45个,上调基因11个,下调基因34个(P<0.05)。差异基因富集于NF-κB信号通路、Wnt信号通路、MAPK-ERK信号通路、JAK-STAT信号通路和DNA损伤应激通路等。结论在发育早期E14.5时Dicer1参与调节多条信号通路,影响部分皮层层次标志物的表达,抑制lncRNA Xist的表达,调节皮质发育。

Objective To explore the role of microRNAs(miRNAs)during early neurodevelopment in mammals with Dicer1 conditional knockout(cKO)mouse by RNA-seq.Methods The animals were divided into Ctrl group and cKO group.HE and immunofluorescence staining were used to observe the histological morphology;Extract total RNA of E14.5 D6-Cre-Dicer1 mice dorsal cortex,using RNA-seq technique to analyze differences at transcriptional level.Results Animals in cKO groups died within a month or so,abnormal development of cortical and hippocampal was recorded at P3.In cKO group transcription expression was different significantly,45 differentially expressed genes were screened,including 11 up-regulated and 34 down-regulated genes(P<0.05)mainly enriched in Wnt signaling pathway,DNA damage response signaling pathway and others.Conclusions At E14.5 cortex,Dicer1 is involved in the regulation of multiple signaling pathways,affecting partial cortical laminar genes expres-sion,inhibiting the expression of lncRNA Xist and regulating cortical development.