title: RNA interference-aided knockdown of a putative saccharopine dehydrogenase leads to abnormal ecdysis in the brown planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae).
abstract: The brown planthopper Nilaparvata lugens is a serious phloem-feeding pest of rice in China. The current study focuses on a saccharopine dehydrogenase (SDH) that catalyzes the penultimate reaction in biosynthesis of the amino acid lysine (Lys), which plays a role in insect growth and carnitine production (as a substrate). The protein, provisionally designated as NlylsSDH [a SDH derived from yeast-like symbiont (YLS) in N. lugens], had a higher transcript level in abdomens, compared with heads, wings, legs and thoraces, which agrees with YLS distribution in N. lugens. Ingestion of Nlylssdh targeted double-stranded RNA (dsNlylssdh) for 5, 10 and 15 days decreased the mRNA abundance in the hoppers by 47, 70 and 31%, respectively, comparing with those ingesting normal or dsegfp diets. Nlylssdh knockdown slightly decreased the body weights, significantly delayed the development of females, and killed approximately 30% of the nymphs. Moreover, some surviving adults showed two apparent phenotypic defects: wing deformation and nymphal cuticles remained on tips of the legs and abdomens. The brachypterours/macropterours and sex ratios (female/male) of the adults on the dsRNA diet were lowered compared with the adults on diets without dsRNA. These results suggest that Nlylssdh encodes a functional SDH protein. The adverse effect of Nlylssdh knockdown on N. lugens implies the importance of Lys in hopper development. This study provides a proof of concept example that Nlylssdh could serve as a possible dsRNA-based pesticide for planthopper control.
authors.affiliation: State Key Laboratory of Rice Biology,China National Rice Research Institute,Hangzhou 310006,China.
authors.forename: P-J
authors.initials: PJ
authors.lastname: Wan
authors.affiliation: State Key Laboratory of Rice Biology,China National Rice Research Institute,Hangzhou 310006,China.
authors.forename: L
authors.initials: L
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Rice Biology,China National Rice Research Institute,Hangzhou 310006,China.
authors.forename: S-Y
authors.initials: SY
authors.lastname: Yuan
authors.affiliation: State Key Laboratory of Rice Biology,China National Rice Research Institute,Hangzhou 310006,China.
authors.forename: Y-H
authors.initials: YH
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Rice Biology,China National Rice Research Institute,Hangzhou 310006,China.
authors.forename: Q
authors.initials: Q
authors.lastname: Fu
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: G-Q
authors.initials: GQ
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D006430:Hemiptera / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D008969:Molecular Sequence Data; D018978:Molting / Q000235:genetics / Q000502:physiology*; D010802:Phylogeny; D034622:RNA Interference; D012443:Saccharopine Dehydrogenases / Q000235:genetics / Q000378:metabolism*
chemical_list: D012443:Saccharopine Dehydrogenases
keywords: Nilaparvata lugens; biosynthesis; ecdysis; lysine; saccharopine dehydrogenase