Project description:The shrimp aquaculture industry is vulnerable to large losses due to acute hepatopancreatic necrosis disease (AHPND), caused by the bacterium Vibrio parahaemolyticus. The mechanism by which the pathogen causes disease, and the host immune response, is not completely understood. The shrimp hepatopancreas is a multi-functional organ with roles in digestion, immunity, molting and reproduction. Therefore, we set out to characterize the cells of the hepatopancreas and the host response to Vibrio parahaemolyticus infection at single-cell resolution. The hepatopancreas from three individual shrimp were processed to create a single-cell transcriptomic atlas. Then the hepatopancreas from three Vibrio parahaemolyticus infected and two mocked treated shrimp were sampled for infection study. All single-cell libraries were generated using the 10X Genomics platform and sequenced on an Illumina sequencer. Data were aligned to the Litopenaeus vannamei reference genome using Cell Ranger. Seurat and clusterProfiler were used for downstream analyses. Cells of the hepatopancreas were characterized and the transcriptomic response to AHPND-causing V. parahaemolyticus was examined. Data will inform further functional studies and has the potential to aid in the development of novel preventative measures or treatments.
Project description:Bacteria in nature are widely exposed to differential fluid shears which are often a trigger for phenotypic switches. The latter mediates transcriptional and translation remodeling of cellular metabolism impacting among others virulence, antimicrobial resistance and stress resistance. In this study, we evaluated the role of fluid shear on phenotypic switch in an acute hepatopancreatic necrosis disease (AHPND)-causing Vibrio parahaemolyticus M0904 strain under both in vitro and in vivo conditions. The results showed that V. parahaemolyticus M0904 grown at lower shaking speed (110 min-1 constant agitation, M0904/110), causing low fluid shear, develop cellular aggregates or floccules. These cells increased levan production (as verified by concanavalin binding) and developed differentially stained colonies on Congo Red agar plates and resistance to antibiotics. In addition, the phenotypic switch causes a major shift in the protein secretome. At 120 min-1 (M0904/120), PirA/B toxins are mainly produced, while at 110 min-1 PirA/B toxin production is stopped and an alkaline phosphatase PhoX becomes the dominant protein in the protein secretome. These observations are matched with a very strong reduction in virulence of M0904/110 towards two crustacean larvae, namely Artemia and Macrobrachium. Taken together, our study provides substantial evidence for the existence of two phenotypic forms in AHPND Vibrio parahaemolyticus strains displaying differential phenotypes that could be of interest in understanding the epidemiology of AHPND under aquaculture conditions. It might provide the basis for AHPND control by steering phenotypes.
Project description:Vibrio parahaemolyticus is a Gram-negative bacterium commonly found in marine and estuarine environments. Acute hepatopancreatic necrosis disease (AHPND) caused by this bacterium is an ongoing problem among shrimp farming industries. V. parahaemolyticus proteins PirA and PirB have been determined to be major virulence factors that induce AHPND. In this study, Pacific white shrimp (Litopenaeus vannamei) were challenged with recombinant PirA and PirB by a reverse gavage method and then at 30 m, 1, 2, 4, and 6 h time points, the hepatopancreas of five individual shrimp were removed and placed into RNA later. We conducted RNA sequencing of the hepatopancreas samples from a no PirA/B control (n = 5) and PirA/B-treated shrimp at the different time intervals (n=5). We evaluated the different gene expression patterns between the time groups to the control with a focus on identifying differences in innate immune function.
Project description:In order to gain a better understanding of the impact of Vibrio parahaemolyticus infection on genetic regulation of Litopenaeus vannamei,we performed a miRNA-seq analysis in the hepatopancreas of Litopenaeus vannamei challenged with Vibrio parahaemolyticus, using the Illumina HiSeq 2500 platform.
2020-06-18 | GSE107696 | GEO
Project description:Transcriptome of Vibrio parahaemolyticus strain AHPND
Project description:In order to gain a better understanding of the impact of Vibrio parahaemolyticus infection on genetic regulation of Litopenaeus vannamei,we performed a transcriptome analysis in the hepatopancreas of Litopenaeus vannamei challenged with Vibrio parahaemolyticus, using the Illumina HiSeq 2500 platform.