Protein expression profiling in the gill of Litopenaeus vannamei (Boone, 1931) naturally infected with white spot syndrome virus

To better understand the molecular pathogenesis of white spot syndrome virus (WSSV) inLitopenaeus vannamei(Boone, 1931), the protein expression profile in gills was characterized. Farmed shrimp WSSV positive were randomly sorted based on nested PCR. The proteomic analysis of gill proteins was performed using two-dimensional electrophoresis (2-DE), with isofocalisation on an immobilized linear gradient (pH 3-10), followed by separation based on molecular weight using 12.5% denaturating polyacrylamide gel electrophoresis (SDS-PAGE). The comparative analysis of the 2-DE profile between the two groups revealed eight differentially expressed spots in gills of naturally infected shrimp. The spots were successfully identified using MALDI-TOF mass spectrometry peptide mass fingerprint. The up-regulated proteins unique to infected shrimp were identified as peptidyl-prolyl isomerase, mortality factor 4-like protein 1, calreticulin, recombination activating protein, failed axon connection protein, 40S ribosomal S2 and N-deacetylase/N-sulfotransferase. The down-regulated protein unique to non-infected shrimp (control group) was identified as an inhibitor of apoptosis. The differentially expressed proteins are involved in several important cellular processes, such as host defence and protein metabolism. The present work contributes to a better understanding of the overall molecular responses elicited by WSSV infection inL. vannamei, as well as to point out potential molecular biomarkers to evaluate the susceptibility to the virus and the sanitary status in farmed shrimp.