The immune defense response and immune-related genes expression in Odontobutis potamophila infected by Aeromonas salmonicida.

Abstract

Aeromonas salmonicida belongs to the Aeromonas family, which could widely infect economic fish, causing diseases and huge economic losses. Recently, A. salmonicida was also detected in diseased Odontobutis potamophila. Transcriptomic model of A. salmonicida-infected O. potamophila was analyzed to reveal immune response. A total of 113,282 unigenes were obtained and annotated in six databases. After 12 h of infection with A. salmonicides, a total of 614 differentially expressed genes (DEGs) (355 up-regulated genes and 259 down-regulated genes) were identified in the head kidney tissues. Following 24 h of infection, a total of 1689 DEGs were detected in the head kidney tissues, including 313 up-regulated genes and 1376 down-regulated genes. GO and KEGG pathway analyses were conducted to provide functional insights and a clearer understanding of the signal transduction pathways associated with the DEGs. Further analysis of the complement and coagulation cascades pathway and PPAR signaling pathway exhibited that the expression of immune genes was widely activated at the beginning of A. salmonicides infection. Additionally, six DEGs were randomly selected and validated using quantitative real-time PCR, showing expression patterns consistent with the high-throughput sequencing data. These results offer important insights that enhance the understanding of immune response in O. potamophila against A. salmonicida infection.