iTRAQ-based quantitative proteomic analysis of differentially expressed proteins in Litopenaeus vannamei in response to infection with WSSV strains varying in virulence

The isobaric tags for relative and absolute quantitation (iTRAQ) were applied to identify differentially expressed proteins (DEPs) in Litopenaeus vannamei in response to different virulence white spot syndrome virus infection. A total of 2780 unique peptides corresponding to 754 proteins were identified. The number of significant differentially expressed proteins was 161, including 38 up-regulated ones and 123 down-regulated ones in low-virulence infection library compared with normal-virulence infection library. Gene Ontology function annotation indicated that the differentially expressed proteins mainly participated in the biological process. Subcellular location classification showed that the largest distribution of differentially expressed proteins was found in the cytoplasm in both down-regulated and up-regulated proteins. Kyoto encyclopaedia of genes and genomes analysis revealed that most of the differentially expressed proteins were involved in carbon metabolism. Moreover, three metabolic pathways, including carbon metabolism, inositol phosphate metabolism, and fructose and mannose metabolism, were significantly affected. Our findings offered a better understanding of the host response to different virulence white spot syndrome virus infection.

White spot syndrome virus (WSSV) is one of the most harmful pathogens in shrimp farming. Previous studies have shown that genetic variations of white spot syndrome virus cause the strains of different virulence. The hosts also show different self-regulation when infected by different viruses. A better understanding of host response to white spot syndrome virus will help elucidate the virulence and pathogenesis of this unique pathogen.