太赫兹辐射暴露引起小鼠视网膜基因表达改变

Terahertz radiation exposure results in altered gene expression profile in mouse retina

目的探讨太赫兹(terahertz,THz)辐射暴露后视网膜组织基因表达变化的整体情况,揭示THz暴露所致视觉系统损伤效应的关键信号通路及关键基因。方法通过平均功率密度80 mW/cm^2的THz辐射暴露小鼠眼部,暴露时长2 min,取暴露后视网膜组织,采用RNA-seq测序分析基因表达变化的整体差异,采用聚类分析及富集分析揭示差异基因富集的信号通路和所揭示的生物功能;并进一步通过Real-time PCR揭示THz辐射暴露对视网膜损伤关键基因表达影响的时效关系。结果以P<0.05、|logFC|≥1为筛选条件对差异表达基因进行筛选,共筛选出上调基因625个,下调基因9个。GO分析差异基因主要分布于细胞外成分,分子功能主要为影响蛋白结合等,生物功能主要为细胞应激反应与细胞增殖等。KEGG信号通路分析结果显示,差异基因主要影响PPAR信号通路、癌症相关信号通路、钙离子信号通路及PI3K-Akt信号通路。通过Real-time PCR对视网膜损伤相关基因进行验证发现,在暴露后5 min及24 h,THz辐射暴露均上调Krt12、Cfd、Wnt3a及Adipoq表达,下调Foxe3、Serpine3、Lix1、Rpe65、Rgr及Arsi基因表达,且暴露后5 min上调或下调幅度明显强于24 h。结论THz辐射能够导致视网膜大量基因表达异常,提示THz暴露可能造成视网膜损伤。

Objective To explore the global changes of gene expression profile in the retina after terahertz(THz)radiation exposure in order to reveal the signal pathways and key genes involved in the process of visual system damage.Methods Mouse eyes were exposed to THz radiation at an average power density of 80 mW for 2 min.Then the retinal tissues were harvested to extract total RNA for RNA-seq analysis.The differential expression genes(DEGs)and their functions were identified with a certain condition for Gene Ontology(GO)analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis.Real-time PCR was used to further explore the time-dependent effects of THz exposure on the expression of the key genes related to retinal injury from DEGs.Results There were 625 up-regulated genes and 9 down-regulated genes screened out through the condition of P<0.05 and|logFC|≥1.The GO analysis revealed that the DEGs were mainly composed of extracellular components as the complementary biological concept of cellular component(CC),mainly related to protein binding as the concept of molecular function(MF),and were associated with response to external stimulus and cell proliferation as the concept of biological process(BP).The KEGG analysis indicated that most DEGs were enriched in the PPAR,PI3 K-Akt,and tumor-and calcium-related signaling pathways.Real-time PCR displayed that the expression levels of Krt12,Cfd,Wnt3 a and Adipoq were up-regulated,while those of Foxe3,Serpine3,Lix1,Rpe65,Rgr and Arsi were down-regulated in the injured retinal tissues after THz irradiation exposure for 5 min and 24 h,and the changes were more significant after 5 minutes’than 24 hours’exposure.Conclusion THz radiation exposure causes abnormal expression of a large number of genes in retinal tissue,indicating the exposure may induce retinal injury.