title: Delivery of chitosan/dsRNA nanoparticles for silencing of wing development vestigial (vg) gene in Aedes aegypti mosquitoes.
abstract: RNA interference (RNAi) has been used as a gene silencing strategy by the introduction of long double stranded RNA (dsRNA) for the control of pest insects. The aim of the present study was to examine whether the expression of vg gene which is responsible for wing development, can be repressed by chitosan/dsRNA based nanoparticles in Aedes aegypti. The vestigial gene (vg) was amplified from adult mosquito and cloned in pLitmus28i vector. Genetically engineered recombinant plasmid was transformed into RNase III deficient strain for synthesis of bacterially expressed dsRNA. Nanoparticles were prepared via electrostatic interaction between cationic polymer chitosan and anionic nucleic acids (dsRNA). The formation of chitosan/dsRNAnanoparticles and their size were confirmed by Atomic force microscopy (AFM). Chitosan/dsRNA mediated knockdown of Enhanced Green Fluorescence Protein (EGFP) was demonstrated in Sf21 cells. Further, we tested whether such an approach could be used to target vg gene in Ae. aegypti. The results showed that chitosan/dsRNA caused significant mortality, delayed growth development and caused adult wing-malformation. A qRT-PCR analysis confirmed that the chitosan/dsRNA mediated transcriptional level was downregulated. Our findings suggest that vg gene intervention strategies through RNAi can emerge as viable option for pest control.
authors.affiliation: Aquatic animal health and environment division, Central institute of brackishwater aquaculture, Chennai 600028, India; Division of Microbiology and Molecular biology, Entomology Research Institute, Loyola College, Chennai 600 034, India.
authors.forename: D
authors.initials: D
authors.lastname: Ramesh Kumar
authors.affiliation: Division of Microbiology and Molecular biology, Entomology Research Institute, Loyola College, Chennai 600 034, India.
authors.forename: P
authors.initials: P
authors.lastname: Saravana Kumar
authors.affiliation: Entomology Research Institute, Loyola College, Chennai 600 034, India.
authors.forename: M Rajiv
authors.initials: MR
authors.lastname: Gandhi
authors.affiliation: Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
authors.forename: Naif Abdullah
authors.initials: NA
authors.lastname: Al-Dhabi
authors.affiliation: Entomology Research Institute, Loyola College, Chennai 600 034, India.
authors.forename: M Gabriel
authors.initials: MG
authors.lastname: Paulraj
authors.affiliation: Entomology Research Institute, Loyola College, Chennai 600 034, India; Visiting Professor Program, Deanship of Scientific Research, College of Science, King Saud University, Riyadh, Saudi Arabia. Electronic address: eriloyola@hotmail.com.
authors.forename: S
authors.initials: S
authors.lastname: Ignacimuthu
mesh_terms: D000330:Aedes / Q000235:genetics* / Q000254:growth & development; D000818:Animals; D048271:Chitosan / Q000737:chemistry*; D004337:Drug Carriers / Q000737:chemistry; D019476:Insect Proteins / Q000172:deficiency* / Q000235:genetics*; D053758:Nanoparticles / Q000737:chemistry*; D034622:RNA Interference; D012330:RNA, Double-Stranded / Q000737:chemistry / Q000235:genetics*; D061987:Sf9 Cells; D018411:Spodoptera; D014921:Wings, Animal / Q000254:growth & development
chemical_list: D004337:Drug Carriers; D019476:Insect Proteins; D012330:RNA, Double-Stranded; D048271:Chitosan
keywords: Chitosan/dsRNA nanoparticles; Vestigial gene (vg)