title: Deep Illumina sequencing reveals conserved and novel microRNAs in grass carp in response to grass carp reovirus infection.
abstract: The grass carp hemorrhagic disease caused by the grass carp reovirus (GCRV) is a major disease that hampers the development of grass carp aquaculture. The mechanism underlying GCRV pathogenesis and hemorrhagic symptoms is still unknown. MicroRNAs (miRNAs) are key regulators involved in various biological processes. The aim of this study was to identify conserved and novel miRNAs in grass carp in response to GCRV infection, as well as attempt to reveal the mechanism underlying GCRV pathogenesis and hemorrhagic symptoms.
  
  
  
  Grass carp were infected with GCRV, and spleen samples were collected at 0 (control), 1, 3, 5, 7, and 9 days post-infection (dpi). These samples were used to construct and sequence small RNA libraries. A total of 1208 miRNAs were identified, of which 278 were known miRNAs and 930 were novel miRNAs. Thirty-six miRNAs were identified to exhibit differential expression when compared with the control, and 536 target genes were predicted for the 36 miRNAs. GO and KEGG enrichment analyses of these target genes showed that many of the significantly enriched terms were associated with immune response, blood coagulation, hemostasis, and complement and coagulation cascades, especially the GO term "blood coagulation" and pathway "complement and coagulation cascades." Ten representative target genes involved in "complement and coagulation cascades" were selected for qPCR analysis, and the results showed that the expression patterns of these target genes were significantly upregulated at 7 dpi, suggesting that the pathway "complement and coagulation cascades" was strongly activated.
  
  
  
  Conserved and novel miRNAs in response to GCRV infection were identified in grass carp, of which 278 were known miRNAs and 930 were novel miRNAs. Many of the target genes involved in immune response, blood coagulation, hemostasis, and complement and coagulation cascades. Strong activation of the pathway "complement and coagulation cascades" may have led to endothelial-cell and blood-cell damage and hemorrhagic symptoms. The present study provides a new insight into understanding the mechanism underlying GCRV pathogenesis and hemorrhagic symptoms.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
authors.forename: Libo
authors.initials: L
authors.lastname: He
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
authors.forename: Aidi
authors.initials: A
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Chu
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
authors.forename: Yongming
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
authors.forename: Lanjie
authors.initials: L
authors.lastname: Liao
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
authors.forename: Zuoyan
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China. wangyp@ihb.ac.cn.
authors.forename: Yaping
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000818:Animals; D002347:Carps / Q000235:genetics* / Q000821:virology*; D017124:Conserved Sequence; D005393:Fish Diseases / Q000821:virology; D020869:Gene Expression Profiling; D063990:Gene Ontology; D059014:High-Throughput Nucleotide Sequencing; D035683:MicroRNAs / Q000235:genetics*; D012087:Reoviridae / Q000502:physiology*; D017423:Sequence Analysis, RNA
chemical_list: D035683:MicroRNAs
keywords: Blood coagulation; Complement and coagulation cascades; Grass carp; Grass carp reovirus; Hemorrhagic symptoms; microRNA