title: Potential of RNAi applications to control viral diseases of farmed shrimp.
abstract: Viral pathogens pose a primary threat to global shrimp aquaculture. Despite the urgent industry need for them, practical anti-viral control methods are unavailable due, in part, to lack of an adaptive immune response in crustaceans that renders conventional vaccination methods ineffective. One currently studied method of high interest for protecting shrimp against viral infection relies on the post-transcriptional gene silencing mechanism called RNA interference (RNAi) that is induced by gene-specific constructs of double stranded RNA (dsRNA). Although this approach was first described for successful protection of shrimp against white spot disease (WSD) by injecting dsRNA specific to genes of white spot syndrome virus (WSSV) into shrimp in the laboratory in 2005 no practical method for use of dsRNA in shrimp farms has been developed to date. The apparent bottleneck for farm-scale applications of RNAi-mediated viral control in shrimp aquaculture is the lack of simple and cost-effective delivery methods. This review summarizes recent studies on use and delivery of dsRNA to shrimp via injection and oral routes in hatcheries and on farms and it discusses the research directions that might lead to development of practical methods for applications with farmed shrimp. Oral delivery methods tested so far include use of dsRNA-expressing bacteria as a component of dry feed pellets or use of living brine shrimp (Artemia) pre-fed with dsRNA before they are fed to shrimp. Also tested have been dsRNA enclosed in nanocontainers including chitosan, liposomes and viral-like particles (VLP) before direct injection or use as components of feed pellets for hatchery or pond-reared shrimp.
authors.affiliation: Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok 10400, Thailand; Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
authors.forename: Ornchuma
authors.initials: O
authors.lastname: Itsathitphaisarn
authors.affiliation: Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Bangkok 10400, Thailand; Department of Biotechnology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
authors.forename: Siripong
authors.initials: S
authors.lastname: Thitamadee
authors.affiliation: Department of Anatomy and Structural Biology, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
authors.forename: Wattana
authors.initials: W
authors.lastname: Weerachatyanukul
authors.affiliation: Shrimp-Pathogen Interaction (SPI) Laboratory, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Yothi Office, Rama VI Rd., Bangkok 10400, Thailand. Electronic address: kallaya@biotec.or.th.
authors.forename: Kallaya
authors.initials: K
authors.lastname: Sritunyalucksana
mesh_terms: D000818:Animals; D017756:Aquaculture; D060467:Disease Resistance / Q000235:genetics*; D033561:Penaeidae / Q000821:virology*; D034622:RNA Interference; D058425:Vaccines, Virus-Like Particle / Q000627:therapeutic use; D014777:Virus Diseases / Q000517:prevention & control
chemical_list: D058425:Vaccines, Virus-Like Particle
keywords: Penaeid shrimp; RNAi; Viral infection; White spot syndrome virus; dsRNA