Xu Xiaoyan, Shen Yubang, Fu Jianjun, Lu Liqun, Li Jiale
Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai 201306, PR China.
National Pathogen Collection Center for Aquatic Animals, College of Fisheries and Life Science, Shanghai Ocean University, 999 Huchenghuan Road, 201306 Shanghai, PR China.
Fish Shellfish Immunol. 2015 Jul;45(1):94-103. doi: 10.1016/j.fsi.2015.02.008. Epub 2015 Feb 16.
MicroRNAs (miRNAs) modulate many biological processes and can be up-or down-regulated in a variety of diseases states, including in bacterial infection. In this study, we characterized miRNAs associated with susceptibility or resistance to motile Aeromonas hydrophila in grass carp (Ctenopharyngodon idella), a commercially important farmed fish species in China. Using Illumina next-generation sequencing, we detected 185 miRNAs in A. hydrophila-susceptible (SGC) and -resistant grass carp (RGC) during immune activation. Twenty-one miRNAs were found to be differentially expressed between SGC and RGC, with 23.8% (5 out 21) exhibiting elevated expression in SGC. Further investigation of a selected five miRNAs indicated differences in the timing and tissue sources of expression. Target genes likely regulated by these miRNAs were identified using computational prediction combined with transcriptome expression data. MiRNA targets of differentially expressed mRNAs included those with functions important for bacterial resistance, such as tlr4 and nfil3-6. In addition, we demonstrated that nfil3-6 and tlr4 genes are direct targets of let-7i and cid-miRn-118. The present study suggested that the multiple miRNAs, displaying diverse kinetics and tissue sources on antibacterial immune processes.
微小RNA（miRNA）可调节多种生物学过程，在包括细菌感染在内的多种疾病状态下可上调或下调。在本研究中，我们鉴定了与草鱼（Ctenopharyngodon idella）对运动性嗜水气单胞菌易感性或抗性相关的miRNA，草鱼是中国一种重要的商业养殖鱼类。利用Illumina下一代测序技术，我们在免疫激活过程中检测了嗜水气单胞菌易感（SGC）和抗性草鱼（RGC）中的185种miRNA。发现21种miRNA在SGC和RGC之间差异表达，其中23.8%（21种中的5种）在SGC中表达升高。对选定的5种miRNA的进一步研究表明，其表达的时间和组织来源存在差异。利用计算预测结合转录组表达数据鉴定了可能受这些miRNA调控的靶基因。差异表达mRNA的miRNA靶标包括对细菌抗性重要的功能基因，如tlr4和nfil3-6。此外，我们证明nfil3-6和tlr4基因是let-7i和cid-miRn-118 的直接靶标。本研究表明，多种miRNA在抗菌免疫过程中表现出不同的动力学和组织来源。
