title: Glutathione S-transferase of brown planthoppers (Nilaparvata lugens) is essential for their adaptation to gramine-containing host plants.
abstract: Plants have evolved complex processes to ward off attacks by insects. In parallel, insects have evolved mechanisms to thwart these plant defenses. To gain insight into mechanisms that mediate this arms race between plants and herbivorous insects, we investigated the interactions between gramine, a toxin synthesized by plants of the family Gramineae, and glutathione S transferase (GST), an enzyme found in insects that is known to detoxify xenobiotics. Here, we demonstrate that rice (Oryza sativa), a hydrophytic plant, also produces gramine and that rice resistance to brown planthoppers (Nilaparvata lugens, BPHs) is highly associated with in planta gramine content. We also show that gramine is a toxicant that causes BPH mortality in vivo and that knockdown of BPH GST gene nlgst1-1 results in increased sensitivity to diets containing gramine. These results suggest that the knockdown of key detoxification genes in sap-sucking insects may provide an avenue for increasing their sensitivity to natural plant-associated defense mechanisms.
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing, China.
authors.forename: Xiao-Qin
authors.initials: XQ
authors.lastname: Sun
authors.forename: Mao-Xin
authors.initials: MX
authors.lastname: Zhang
authors.forename: Jing-Ya
authors.initials: JY
authors.lastname: Yu
authors.forename: Yu
authors.initials: Y
authors.lastname: Jin
authors.forename: Bing
authors.initials: B
authors.lastname: Ling
authors.forename: Jin-Ping
authors.initials: JP
authors.lastname: Du
authors.forename: Gui-Hua
authors.initials: GH
authors.lastname: Li
authors.forename: Qing-Ming
authors.initials: QM
authors.lastname: Qin
authors.forename: Qing-Nian
authors.initials: QN
authors.lastname: Cai
mesh_terms: D000222:Adaptation, Physiological; D000470:Alkaloids / Q000378:metabolism*; D000818:Animals; D055785:Gene Knockdown Techniques; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism*; D006430:Hemiptera / Q000201:enzymology*; D060434:Herbivory; D026121:Indole Alkaloids; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism*; D009758:Nymph / Q000201:enzymology; D012275:Oryza / Q000378:metabolism*; D010571:Pest Control; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015430:Weight Gain
chemical_list: D000470:Alkaloids; D026121:Indole Alkaloids; D019476:Insect Proteins; D012333:RNA, Messenger; D005982:Glutathione Transferase; C007884:gramine