title: Characterization of two juvenile hormone epoxide hydrolases by RNA interference in the Colorado potato beetle.
abstract: In insect, juvenile hormone (JH) titers are tightly regulated in different development stages through synthesis and degradation pathways. During JH degradation, JH epoxide hydrolase (JHEH) converts JH to JH diol, and hydrolyses JH acid to JH acid diol. In this study, two full length LdJHEH cDNAs were cloned from Leptinotarsa decemlineata, and were provisionally designated LdJHEH1 and LdJHEH2. Both mRNAs were detectable in the thoracic muscles, brain-corpora cardiaca-corpora allata complex, foregut, midgut, hindgut, ventral ganglia, Malpighian tubules, fat bodies, epidermis, and hemocytes of the day 2 fourth-instar larvae, and in female ovaries as well as male reproductive organs of the adults. Moreover, both LdJHEH1 and LdJHEH2 were expressed throughout all larval life, with the highest peaks occurring 32h after ecdysis of the final (fourth) instar larvae. Four double-stranded RNAs (dsRNAs) (dsJHEH1-1, dsJHEH1-2, dsJHEH2-1, dsJHEH2-2) respectively targeting LdJHEH1 and LdJHEH2 were constructed and bacterially expressed. Ingestion of dsJHEH1-1, dsJHEH1-2, dsJHEH2-1, dsJHEH2-2, and a mixture of dsJHEH1-1+dsJHEH2-1 successfully knocked down corresponding target gene function, and significantly increased JH titer and upregulated Krüppel homolog 1 (LdKr-h1) mRNA level. Knockdown of either LdJHEH1 or LdJHEH2, or both genes slightly reduced larval weight and delayed larval development, and significantly impaired adult emergence. Therefore, it is suggested that knockdown LdJHEH1 and LdJHEH2 affected JH degradation in the Colorado potato beetle.
authors.affiliation: Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: 287148308@qq.com.
authors.forename: Feng-Gong
authors.initials: FG
authors.lastname: Lü
authors.affiliation: Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China. Electronic address: 176061610@qq.com.
authors.forename: Kai-Yun
authors.initials: KY
authors.lastname: Fu
authors.affiliation: Department of Plant Protection, Xinjiang Academy of Agricultural Sciences, Urumqi 830091, China. Electronic address: gwc1966@163.com.
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. Electronic address: ligq@njau.edu.cn.
authors.forename: Guo-Qing
authors.initials: GQ
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001517:Coleoptera / Q000201:enzymology*; D004851:Epoxide Hydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D007605:Juvenile Hormones / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D034622:RNA Interference; D017386:Sequence Homology, Amino Acid
chemical_list: D007605:Juvenile Hormones; D004851:Epoxide Hydrolases
keywords: Juvenile hormone epoxide hydrolase; Juvenile hormone titer; Leptinotarsa decemlineata; Performance; RNA interference