title: The Tribolium chitin synthase genes TcCHS1 and TcCHS2 are specialized for synthesis of epidermal cuticle and midgut peritrophic matrix.
abstract: Functional analysis of the two chitin synthase genes, TcCHS1 and TcCHS2, in the red flour beetle, Tribolium castaneum, revealed unique and complementary roles for each gene. TcCHS1-specific RNA interference (RNAi) disrupted all three types of moult (larval-larval, larval-pupal and pupal-adult) and greatly reduced whole-body chitin content. Exon-specific RNAi showed that splice variant 8a of TcCHS1 was required for both the larval-pupal and pupal-adult moults, whereas splice variant 8b was required only for the latter. TcCHS2-specific RNAi had no effect on metamorphosis or on total body chitin content. However, RNAi-mediated down-regulation of TcCHS2, but not TcCHS1, led to cessation of feeding, a dramatic shrinkage in larval size and reduced chitin content in the midgut.
authors.affiliation: USDA-ARS-Grain Marketing and Production Research Center, Manhattan, KS 66502, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Arakane
authors.forename: S
authors.initials: S
authors.lastname: Muthukrishnan
authors.forename: K J
authors.initials: KJ
authors.lastname: Kramer
authors.forename: C A
authors.initials: CA
authors.lastname: Specht
authors.forename: Y
authors.initials: Y
authors.lastname: Tomoyasu
authors.forename: M D
authors.initials: MD
authors.lastname: Lorenzen
authors.forename: M
authors.initials: M
authors.lastname: Kanost
authors.forename: R W
authors.initials: RW
authors.lastname: Beeman
mesh_terms: D000818:Animals; D001483:Base Sequence; D002686:Chitin / Q000096:biosynthesis*; D002687:Chitin Synthase / Q000096:biosynthesis / Q000235:genetics*; D004817:Epidermis / Q000201:enzymology / Q000254:growth & development; D041981:Gastrointestinal Tract / Q000201:enzymology / Q000254:growth & development; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D020868:Gene Silencing; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D007814:Larva / Q000378:metabolism; D018978:Molting / Q000502:physiology; D010641:Phenotype; D011679:Pupa / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D014018:Tissue Distribution; D014231:Tribolium / Q000196:embryology* / Q000201:enzymology* / Q000235:genetics
chemical_list: D019476:Insect Proteins; D012333:RNA, Messenger; D002686:Chitin; D002687:Chitin Synthase