Characterization Of White Spot Syndrome Virus Immediate-early Gene WSV083and STAT From Litopenaeus Vannamei

As an important pathogen of the shrimp aquaculture, white spot syndrome virus(WSSV) has caused the greatest challenge to the worldwide shrimp aquaculture. Thecombination of studying the shrimp innate immunity system and the virus infectionmechanism can provide more pertinent way to improve the antiviral immunity ofshrimps, thus to prevent and inhibit the spread of WSSV.WSSV interacts with integrin during infection of shrimps and modulate the focaladhesion kinase which is known as a regulator of several downstream signalingpathways. Viral protein kinases are thought to be important for virus infection byregulating the host signaling pathways. WSV083is an immediate-early gene of whitespot syndrome virus that contains a Ser/Thr protein kinase domain. In this study, co-transfection of WSV083and MjFAK genes proceeded in insect cells revealed that theMjFAK phosphorylation and cell adhesion activity could be inhibited by theexpression of WSV083. Moreover, silencing of FAK gene through RNAi acceleratedthe shrimp death rate upon WSSV challenge. These results suggest that modulation ofFAK phosphorylation by WSV083plays a critical role in the pathogenesis of WSSVinfection.The previous study has implied that the shrimp STAT, which is critical for manygenes’ transcription, has intimate role during WSSV infection. In the present study, wehave used the in vitro and in vivo methods to demonstrate that besides WSV069promoter, shrimp STAT can bind other two promoters of WSSV immediate-earlygenes WSV051and WSV249. In addition, we also established an efficient method ofChromatin Immunoprecipitation to seek for possible DNA binding candidates byinterested protein, which will pave the way to study the host gene regulation duringvirus infection. In the present research, we have performed preliminary research in thecharacterization of WSSV immediate-early gene WSV083and Litopenaeus vannameiSignal transducers and activators of transcription (LvSTAT), which will provide newinsight into the further investigation on the Host/Pathogen relationships.