人星状病毒临床分离株感染CaCo-2细胞的转录组分析

Transcriptome analysis of clinically isolated human astrovirus in CaCo-2 cells

人星状病毒（human astrovirus,HAstV）是引起婴幼儿病毒性腹泻的重要病原之一,但其致病机制及与宿主相互作用的数据非常有限。本研究旨在了解HAstV感染细胞后对宿主基因在转录水平上的影响。首先,利用临床分离HAstV毒株感染CaCo-2细胞,用实时定量反转录-聚合酶链反应（reverse transcriptasepolymerase chain reaction,RT-PCR）检测细胞培养上清液中的病毒总RNA,结果显示接种后9~24h病毒总RNA拷贝数明显增加。然后,利用转录组测序全面比较感染与未感染HAstV的CaCo-2细胞转录本,筛选两者间的差异表达基因;并应用KEGG信号通路富集性方法分析差异表达基因相关的信号通路。结果显示,差异基因富集在两条信号通路上（P〈0.05）,分别为轴突导向通路和Ras信号通路。本研究首次利用深度测序技术分析了HAstV感染对宿主基因在转录水平上的影响,为进一步研究HAstV致病机制等提供了方向。

Human astrovirus（HAstV）is one of the major causes of viral gastroenteritis in infants and young children.However,data on the host response to and pathogenesis of HAstV infection are limited.The primary goal of this study was to identify differentially expressed genes and enriched pathways associated with HAstV infection in human CaCo-2cells.The clinical isolates of HAstV were used to infect CaCo-2cells and total viral RNAs in the extracellular medium were quantitatively detected. Real-time reverse transcriptase-polymerase chain reaction（RT-PCR）assay was applied to clearly demonstrate a significant increase in the amount of viral RNAs in the culture supernatant at 9-24hpost-infection.Finally,RNA sequencing was performed to compare the transcriptomes of CaCo-2cells infected with and without a clinically isolated HAstV strain.Statistical analyses on differentially expressed genes revealed that axon guidance and Ras signaling pathways were altered in HAstV-5-infected CaCo-2cells（P0.05）.This is the first report on the deep-sequencing analysis of transcripts of CaCo-2cells infected with HAstV.The data from this study can serve as a basis for future studies of HAstV pathogenesis.