Transcriptome analysis reveals immune-related differentially expressed genes in the hepatopancreas and gills of Penaeus vannamei after Vibrio anguillarum infection

Penaeus vannamei is one of the commercially important aquaculture species in the world but sensitive to Vibrio anguillarum infection. To understand the immune response of P. vannamei against V. anguillarum infection, the transcriptomes of hepatopancreas and gills of P. vannamei were analysed before and after V. anguillarum infection. Total 6213 differentially expressed genes (DEGs) were obtained from the hepatopancreas, and 3780 were obtained from the gills. The DEGs of interest were screened to construct a heat map. The reliability and accuracy of the transcriptome data were verified using RT-qPCR. HSP70 and ARF6 were found highly expressed in both hepatopancreas and gills, while MLC2s encoded by two different gene sequences were found to be expressed in hepatopancreas and gills. Six immune-related DEGs were identified from the protein-protein interaction (PPI) network including the HSP70, ARF6 and MLC2s. The sub-network of PPI was constructed to explore the mode of interaction of immune-related DEGs with their neighbouring proteins. Based on the result of PPI network, we infer that phosphorylated MLC2-1 conducts signal transduction to induce leukocyte transendothelial migration in P. vannamei gills tissue while MLC2-2 plays a role in immunity of V. anguillarum infection not only through activating signal transduction to mediate immune responses but also through the formation of phagosomes in hepatopancreas tissue. HSP70 is associated with the transporting exogenous cargos through presenting antigenic peptides in the process of V. anguillarum infection in P. vannamei. ARF6 interacts with Rab proteins to regulate phagolysosome formation by regulating GTPase activity in P. vannamei gills tissue. In hepatopancreas tissue, ARF6 plays a role in immunity by interacting with cytohesin. This study will contribute to further exploring the immune mechanism of P. vannamei to V. anguillarum infection.