Transcriptome analysis of Macrobrachium rosenbergii hepatopancreas in response to Vibrio harveyi infection

Abstract

The giant freshwater prawn, Macrobrachium rosenbergii, is mass cultivated with production exceeding 200,000 tons per year since 2002. Lately, bacterial and viral infections have resulted in mortalities significantly affecting production. Vibrio harveyi causes hepatopancreatic nuclear deformation and lipid breakdown in post-larval juvenile prawns. To facilitate the understanding of the molecular factors underlying host defence against the pathogen, we investigated the transcriptome and differentially expressed gene (DEG) profiles of the hepatopancreas from M. rosenbergii infected with V. harveyi. A total of 1,884 and 6,809 unigenes in control (PBS-treated) and Vibrio-infected groups, respectively, were assembled from the transcriptome. A significant proportion of unigenes (76.56%) annotated to homologous proteins in the Protostome database. KOG analysis identified the distribution of unigenes under translation, ribosomal structure and biogenesis, while GO and KEGG analysis indicated genes involved in metabolism and genetic information processing, respectively. The DEG analysis produced a total of 1,911 aberrantly expressed sequences, with 1,805 and 106 sequences significantly down- or upregulated (based on log2[FC]), respectively. Among the downregulated sequences, we identified ferritin, haemolysin C, chitin synthase, zinc metalloprotease and glycerol kinase. This study has provided insights to access a greater number of traits to study bacterial pathogenicity in the host, thus contributing to the defences of giant freshwater prawn.