Comparative transcriptomic analysis of Marsupenaeus japonicus hepatopancreas in response to Vibrio parahaemolyticus and white spot syndrome virus.

Vibrio parahaemolyticus and white spot syndrome virus (WSSV) are pathogens that cause epidemics in kuruma shrimp (Marsupenaeus japonicus) during aquaculture, resulting in severe economic losses to local farmers. To characterise the mechanisms of the molecular responses to V. parahaemolyticus and WSSV infection in M. japonicus, the transcriptome of hepatopancreas was sequenced using next-generation sequencing after infection. A total of 29,180 unigenes were assembled, with an average length of 1,151 bp (N50 = 1,951 bp). After BLASTX searching against the Nr database (E-value cut-off = 10-5), 15,176 assembled unigenes remained, with 3,039 and 1,803 differentially expressed transcripts identified in the V. parahaemolyticus- and WSSV-infected groups, respectively. Of these, 1466 transcripts were up-regulated and 1573 were down-regulated in V. parahaemolyticus-infected shrimps, and 970 transcripts were up-regulated and 833 were down-regulated in the WSSV-infected shrimps. Additionally, 761 transcripts were differentially expressed in both V. parahaemolyticus- and WSSV-infected shrimps. Several known immune-related genes including caspase 4, integrin, crustin, ubiquitin-conjugating enzyme E2, C-type lectin, and α2-macroglobulin were among the differentially expressed transcripts. These results provide valuable information for characterising the immune mechanisms of the shrimp responses of to V. parahaemolyticus andWSSV infection.