Transcriptomic analysis reveals differential gene expression in spleen cells of Chinese soft-shelled turtle infected with Bacillus cereus BC12.

Bacillus cereus infection has emerged as a leading cause of high mortality of Chinese soft-shelled turtle (Pelodiscus sinensis) in aquaculture. Elucidating the complex physiological processes and differentially expressed genes (DEGs) of P. sinensis in response to bacterial pathogens will help us explore strategies to combat bacterial infection. In this study, Illumina-based RNA-Seq was used to analyze the significantly active DEGs and pathways in the spleen of P. sinensis challenged by B. cereus BC12. A total of 973 DEGs were identified. These DEGs were significantly enriched in 5,421 Gene Ontology (GO) terms and 147 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways through enrichment analysis. The significantly active pathways included NOD-like receptor signaling pathway (pss04621), cytosolic DNA-sensing pathway (pss04623), cell cycle (pss04110) and spliceosome (pss03040). At 48 h post-infection (hpi), the NF-κB signaling pathway was downregulated, and cell cycle-related gene regulation was disrupted. Additionally, the expression of key spliceosome genes was downregulated. In summary, our results demonstrated the active relevant DEGs and pathways in the splenic cells of P. sinensis at 48 hpi with B. cereus BC12. These results offer valuable insights into the investigation of the molecular mechanisms underlying the resistance of P. sinensis to microbial infections.