Vibrio parahaemolyticus is a Gram-negative bacterium commonly found in marine and estuarine environments and is endemic among the global shrimp aquaculture industry. V. parahaemolyticus proteins PirA and PirB have been determined to be major virulence factors that contribute significantly to the development of acute hepatopancreatic necrosis disease (AHPND). Our previous work demonstrated the lethality of recombinant PirA and PirB proteins to Pacific white shrimp (Penaeus vannamei). To understand the host response to these proteins, recombinant PirA and PirB proteins were administered using a reverse gavage method and individual shrimp were sampled over time. Shrimp hepatopancreas mRNA libraries were generated and bulk RNA sequencing was performed on control and recombinant PirA/B-treated samples.
Differentially expressed genes (DEGs) were identified among the assayed time points (1h up to 6h post challenge), and ranged from approximate 100 at the earliest time points to over 1,000 at later times.
DEGs that were co-expressed at the later time points (2h, 4h, 6h) were also identified and gene associations were established to predict functional physiological networks. Among these were several cell signaling and innate immune function processes (Table 1). From these functional analyses, a candidate gene list was created and included several caspases, integrins, Ras-related proteins and scavenger receptors as potential targets for future examination.
Based on these data, single-cell RNA sequencing of V. parahaemolyticus infected shrimp hepatopancreas over time-course of infection studies are underway. Progress on single-cell studies will also be presented.