Transcriptome profile of Amur sturgeon (Acipenser schrenckii) liver provides insights into immune modulation in response to Yersinia ruckeri infection

Amur sturgeon Acipenser schrenckii, an economically important freshwater fish cultured in China, is now facing numerous bacterial diseases during aquaculture. Infection by Yersina ruckeri causes high mortality and great economic loss in sturgeon culture. To better understand the immune response of Amur sturgeon to Y. ruckeri infection, we performed the transcriptome analysis using livers from Y. ruckeri-infected fish and a control group through RNA-Seq technology. Totally 119 300 unigenes with high quality were obtained. Moreover, 1112 differently expressed genes (DEGs) including 468 up-regulated genes and 644 down-regulated genes were identified based on the expression patterns. 63 immune-related DEGs, such as TLR5, IL-8, NALP3, CCL19/21, C1qC, Hsp70/90 and MHCI, were identified and further divided into 15 KEGG pathways via enrichment analysis using KEGG database. The expression patterns of DEGs were validated by qRT-PCR. In addition, 55 990 potential SSRs were identified from 34 580 transcripts, and 1 696 286 candidate SNPs were identified in the A. schrenckii liver transcriptome. This study will provide the first and crucial information on the immune mechanism of Amur sturgeon against bacterial infection.