60Co γ射线照射致小鼠肝脏的miRNAs表达改变

目的 应用miRNA芯片筛选4 Gy60Co γ射线照射后小鼠肝脏中差异表达的miRNAs,生物信息学方法探索差异表达miRNAs调控的主要功能.方法 SPF级C57BL/6J小鼠接受4 Gy60Co γ射线单次全身照射后,进行外周血白细胞计数和骨髓嗜多染红细胞微核计数.应用miRNA芯片筛选照射后小鼠肝脏中差异表达的miRNAs,用miRNA特异引物对部分差异表达miRNA进行实时定量PCR(real time PCR)验证.运用生物信息学方法,对差异miRNAs靶基因及调控功能进行预测.结果 4 Gyγ射线照射后,外周血白细胞总数与对照组相比显著减少(t=2.87,P＜0.05),而骨髓嗜多染红细胞微核率与对照组相比显著增加(t=-2.91,P＜0.05).miRNA芯片结果显示,照射组与对照组差异表达的miRNAs共17个,其中9个表达上调,8个表达下调.miR-124和miR-34a的实时荧光定量RT-PCR验证结果与芯片结果一致.GO分析发现,与黏附、细胞周期相关的通路被抑制,一些免疫相关通路被激活.结论 miR-34a和miR-194参与了急性辐射损伤的调控,起主要调控作用的miRNAs还有miR-124、miR-382和miR-92a*.

Abstract：

Objective To investigate the differential expression profiles of microRNAs in the liver of 60Co γ-ray irradiated mice using microRNA microarray and to explore their main functions by bioinformatic analysis.Methods After SPF C57BL/6J mice expose to 4 Gy-single whole body radiation,total number of peripheral WBC and the fMNPCE were measured at 3 d.The differentially expressed miRNAs in mouse liver were detected with miRNA microarray,miRNA-124 and miR-34a were confirmed by real time RT-PCR assay.Bioinformatic analysis was applied to explore target genes and the main functions of the differential expressed miRNAs.Results Compared with control group,the total number of peripheral WBC decreased( t = 2.87,P ＜ 0.05 ) ,while the fMNPCE in bone marrow increased ( t =-2.91,P ＜0.05) after 4 Gy γ-ray irradiation.miRNA microarray revealed that 17 miRNAs were differentially expressed,in which 9 up-regulated,8 down-regulated.The expression levels of miR-124 and miR-34a were coincident with the result of real time RT-PCR.GO analysis showed that some pathways including adherens junction and cell cycle were suppressed,while some immune-related pathways were activated.Conclusions miR-34a and miR-194 were involved in the regulation of acute radiation damage,some other miRNAs including miR-124、miR-382 and miR-92a* also played important roles in radiation process.