title: RNA interference ofchitin synthasegenes inhibits chitin biosynthesis and affects larval performance inLeptinotarsa decemlineata(Say).
abstract: Dietary introduction of bacterially expressed double-stranded RNA (dsRNA) has great potential for management ofLeptinotarsa decemlineata. Identification of the most attractive candidate genes for RNA interference (RNAi) is the first step. In the present paper, three complete chitin synthase cDNA sequences (LdChSAa,LdChSAbandLdChSB) were cloned.LdChSAaandLdChSAb, two splicing variants ofLdChSAgene, were highly expressed in ectodermally-derived epidermal cells forming epidermis, trachea, foregut and hindgut, whereasLdChSBwas mainly transcribed in midgut cells. Feeding bacterially expressed dsChSA(derived from a common fragment ofLdChSAaandLdChSAb), dsChSAa, dsChSAband dsChSBin the second- and fourth-instar larvae specifically knocked down their target mRNAs. RNAi ofLdChSAa+LdChSAbandLdChSAalowered chitin contents in whole body and integument samples, and thinned tracheal taenidia. The resulting larvae failed to ecdyse, pupate, or emerge as adults. Comparably, knockdown ofLdChSAbmainly affected pupal-adult molting. TheLdChSAbRNAi pupae did not completely shed the old larval exuviae, which caused failure of adult emergence. In contrast, silencing ofLdChSBsignificantly reduced foliage consumption, decreased chitin content in midgut sample, damaged midgut peritrophic matrix, and retarded larval growth. As a result, the development of theLdChSBRNAi hypomorphs was arrested. Our data reveal that theseLdChSs are among the effective candidate genes for an RNAi-based control strategy againstL. decemlineata.
authors.affiliation: Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Ji-Feng
authors.initials: JF
authors.lastname: Shi
authors.affiliation: Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Mu
authors.affiliation: Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Plant Protection, Xinjiang Academy of Agricultural Sciences.
authors.forename: Wen-Chao
authors.initials: WC
authors.lastname: Guo
authors.affiliation: Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Guo-Qing
authors.initials: GQ
authors.lastname: Li
mesh_terms: D000818:Animals; D002686:Chitin / Q000096:biosynthesis*; D002687:Chitin Synthase / Q000235:genetics / Q000378:metabolism*; D001517:Coleoptera / Q000235:genetics / Q000378:metabolism*; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D007814:Larva / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics
chemical_list: D019476:Insect Proteins; D012333:RNA, Messenger; D002686:Chitin; D002687:Chitin Synthase
keywords: Leptinotarsa decemlineata; RNA interference; chitin synthase; control