Juvenile hormone (JH) esterase activity but not JH epoxide hydrolase activity is downregulated in larval Adoxophyes honmai following nucleopolyhedroviruses infection.
Juvenile hormones (JHs) and ecdysteroids are critical insect developmental hormones. JH esterase (JHE) and JH epoxide hydrolase (JHEH) are JH-selective enzymes that metabolize JH and thus regulate the titer of JH. Baculoviruses are known to alter host endocrine regulation. The nucleopolyhedroviruses, AdhoNPV and AdorNPV, are known to have slow and fast killing activity against Adoxophyes honmai (Lepidoptera: Tortricidae), respectively. Here we found that when penultimate (4th) instar A. honmai are inoculated with AdhoNPV or AdorNPV, the mean survival time is 9.7 and 8.2 days, respectively. The larvae molted once but did not pupate. The AdhoNPV- or AdorNPV-infected larvae did not show a dramatic increase in JHE activity as was found in mock-infected larvae, instead they showed a marked decrease in JHE activity. In contrast, both viral infections had no effect on JHEH activity. In order to further characterize the JHE activity, the JHE-coding sequence of A. honmai (ahjhe) was cloned and confirmed to encode a biologically active JHE. Quantitative real-time PCR analysis of ahjhe expression in 4th and 5th instar A. honmai revealed that AdhoNPV and AdorNPV are able to reduce ahjhe expression levels.
Department of Biological Production Science, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan; Department of Entomology and Nematology, and Comprehensive Cancer Center, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
Yasumasa
Y
Saito
Department of Entomology and Nematology, and Comprehensive Cancer Center, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
Shizuo G
SG
Kamita
Department of Entomology and Nematology, and Comprehensive Cancer Center, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
Bruce D
BD
Hammock
Department of Biological Production Science, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan.
Yasuhisa
Y
Kunimi
Department of Biological Production Science, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan.
Maki N
MN
Inoue
Department of Biological Production Science, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo 183-8509, Japan. Electronic address: madoka@cc.tuat.ac.jp.
Madoka
M
Nakai
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002265:Carboxylic Ester Hydrolases / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D004851:Epoxide Hydrolases / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism*; D007814:Larva / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000821:virology; D008297:Male; D008969:Molecular Sequence Data; D009036:Moths / Q000201:enzymology / Q000235:genetics / Q000254:growth & development* / Q000821:virology*; D017924:Nucleopolyhedroviruses / Q000502:physiology*; D010802:Phylogeny
D019476:Insect Proteins; D002265:Carboxylic Ester Hydrolases; C038003:juvenile hormone esterase; D004851:Epoxide Hydrolases; C055698:juvenile hormone epoxide hydrolase
Adoxophyes honmai; Baculovirus; JH epoxide hydrolase (JHEH); Juvenile hormone esterase (JHE); Nucleopolyhedrovirus; qRT-PCR