产肠毒素大肠杆菌F41感染猪小肠上皮细胞初期lncRNA的表达谱分析

本研究旨在分析产肠毒素大肠杆菌（enterotoxigenic Escherichia coli，ETEC）感染猪小肠上皮细胞（IPEC-J2）后，在感染初期细胞内长链非编码RNA （long non coding RNA，lncRNA）的表达谱变化，探究lncRNA在ETEC感染初期所起到的调控作用。使用ETEC F41感染IPEC-J2，在感染前和感染初期（感染后4 h）收集细胞，通过Illumina Hiseq Xten平台进行高通量测序，共发现lncRNA 9 975条。感染初期与感染前相比，共发现100条差异表达lncRNA，其中40条表达上调，60条表达下调。通过miRanda-3.3a和psRobot_v1.2软件共同预测差异表达lncRNA的靶基因，并对差异表达lncRNA的靶基因进行GO功能和KEGG通路富集分析。结果显示，感染初期差异表达lncRNA的靶基因显著富集于细胞核、核仁、代谢过程调控及发育过程等GO功能条目中。KEGG分析表明，感染初期差异表达lncRNA的靶基因主要富集在PI3K-Akt信号通路、肌动蛋白细胞骨架调节、黏附斑及细胞周期等信号通路。利用实时荧光定量PCR随机验证了5条差异表达lncRNA，结果与测序分析中表达变化趋势一致。本研究对ETEC感染IPEC-J2细胞初期的lncRNA表达谱进行了差异分析，为深入探究lncRNA在ETEC感染初期中的作用机制提供了参考依据。

Analysis of lncRNA Expression Profile in Porcine Intestinal Epithelial Cells Infected with Enterotoxigenic Escherichia coli F41 at Early Stage

To explore the role of long noncoding RNA (lncRNA) at early stage of enterotoxigenic Escherichia coli (ETEC) infection,the expression profile of lncRNAs in the porcine intestinal epithelial cells (IPEC-J2) infected with ETEC was analyzed.ETEC F41 strain was used to infect IPEC-J2 cells.The cells were collected before infection and at early infection (4 h post infection),followed by high-throughput sequencing via the Illumina HiSeq Xten platform.A total of 9 975 lncRNAs were discovered in this study.Compared with cells before infection,100 differentially expressed lncRNAs were found at the early stage of ETEC infection.Among them,40 differentially expressed lncRNAs were up-regulated,and 60 differentially expressed lncRNAs were down-regulated.The target genes of differentially expressed lncRNAs were predicted using miRanda-3.3a and psRobot_v1.2 software,followed by GO and KEGG pathway enrichment analysis.The results showed that at the early stage of infection,the target genes of differentially expressed lncRNAs were significantly enriched in the GO functional items such as nuclear,nucleolus,metabolic process regulation and development process.The KEGG analysis showed that the target genes of differentially expressed lncRNAs at the early stage of infection were significantly enriched in the pathways including PI3K-Akt signaling pathway,regulation of actin cytoskeleton,focal adhesion and cell cycle.Real-time quantitative PCR was performed to validate the expression of 5 randomly selected differentially expressed lncRNAs,which showed that the expression differences before and after infection were consistent with the sequencing results.This study analyzed the lncRNA expression profile of IPEC-J2 cells infected with ETEC at the early stage,which provided a basis for exploring the functional mechanism of key lncRNAs during ETEC infection.