Plant & Animal Genome IX Conference Plant & Animal Genome IX Conference
Workshop: Aquaculture
W217
White spot Virus (WSV) is currently the most devastating viral pathogen threatening the shrimp farming industry worldwide. The mRNA differential display technique was used to isolate the differentially expressed genes from WSV infected in Penaeus stylirostris. Juvenile pathogen free P. stylirostris (~3-4 g) were injected with 30 µl tissue homogenate from healthy or WSV infected (30 µl » 1 x 106 copies of WSV) shrimp. Injected animals were sacrificed 40 h p.i. and DNA and RNA were extracted from the hepatopancreas tissue. Fifty-four differentially and one constitutively expressed cDNAs were isolated, cloned and sequenced. Twenty-nine cDNAs were up and 25 were down-regulated in WSV infected animals. Six out of 54 cDNAs were redundant, 7 cDNAs had microsatellite sequence and one contained a combination of satellite and microsatellite sequence. Among the differentially expressed cDNAs, four showed varying levels of similarities with mitochondrial ATPase subunit 6 of P. notialis; Nuclear Transport Protein of yeast; horseshoe crab Kex2-like endoprotease and human collagen. The constitutively expressed cDNA showed significant similarity with the EF1-alpha gene of yeast and shrimp. Differential expression of 25 cDNAs was further tested by qPCR. Twelve cDNAs were up and 8 were down regulated more than 5 fold and 5 cDNAs showed less than 2 fold changes in expression between healthy and WSV infected animals. One cDNA appeared to represent a WSV encoded gene, since it was detected only in WSV infected but not in healthy animals. Differential expression was also confirmed by Northern blot hybridization for a subset of cDNAs. Further characterization of these differentially expressed genes will help to elucidate their role in WSV pathogenesis.