Transcriptome analysis of Pacific white shrimp (Liptopenaeus vannamei) after exposure to recombinant Vibrio parahaemolyticus PirA and PirB proteins

Authors: Lange, Miles; Abernathy, Jason; Rawles, Anna; Zhang, Dunhua; Shoemaker, Craig; Bader, Troy; Beck, Benjamin

Submitted to: Fish and Shellfish Immunology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/19/2022
Publication Date: 1/19/2023
Citation: Lange, M.D., Abernathy, J.W., Rawles, A.A., Zhang, D., Shoemaker, C.A., Bader, T.J., Beck, B.H. 2023. Transcriptome analysis of Pacific white shrimp (Liptopenaeus vannamei) after exposure to recombinant Vibrio parahaemolyticus PirA and PirB proteins. Fish and Shellfish Immunology. 132. Article 108502. https://doi.org/10.1016/j.fsi.2022.108502.
DOI: https://doi.org/10.1016/j.fsi.2022.108502

Interpretive Summary: Pacific white shrimp (Litopenaeus vannamei) commercial production represents one of the largest sectors of global aquaculture with production estimated at 5.8 million tons annually. Due to the way they are cultured, shrimp are vulnerable to a wide array of bacterial and viral pathogens. Vibrio parahaemolyticus is a Gram-negative bacterium that has been identified as the causative agent of acute hepatopancreatic necrosis disease (AHPND) in shrimp. The identification of the major virulence factor associated with this disease was determined to be two proteins (PirA/B) encoded by a plasmid, the loss of which could revert isolates back to a less lethal form of AHPND. To further understand the processes by which the shrimp host responds to the Pir toxin we used RNA sequencing technology to develop shrimp hepatopancreas transcriptomes at different time points after exposure to recombinant V. parahaemolyticus Pir A/B proteins. When compared to non-exposed shrimp, we identified significant differential gene expression over the time course post-exposure to the rPirA/B proteins. Through further functional analyses we identified multiple critical regulatory pathways that were perturbed, including those involved in cell signaling and innate immune processes. As these Pir A/B protein products harbored in V. parahaemolyticus plasmids have been identified as the causative agent in AHPND, this information contained will provide additional insight into specific host-toxin interactions.

Technical Abstract: 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 to the development of acute hepatopancreatic necrosis disease. Our previous work had demonstrated the lethality of recombinant(r) PirA and PirB proteins to Pacific white shrimp (Litopenaeus vannamei). To understand the host response to these proteins, rPirA and rPirB proteins were administered using a reverse gavage method and individual shrimp were then sampled over time. Shrimp hepatopancreas libraries were generated and RNA sequencing was performed on the control and rPirA/B-treated samples. Differentially expressed genes were identified among the assayed time points. Differentially expressed genes that were co-expressed at the later time points (2-, 4- and 6-h) were also identified and gene associations were established to predict functional physiological networks. Our analysis revealed exposure to rPirA and rPirB proteins initiated an early host response involving several cell survival, signaling and innate immune processes.