title: Insect transferrin functions as an antioxidant protein in a beetle larva.
abstract: In insects transferrin is known as an iron transporter, an antibiotic agent, a vitellogenin, and a juvenile hormone regulated protein. Here, a novel functional role for insect transferrin as an antioxidant protein is demonstrated. Stressors, such as heat shock, fungal challenge, and H(2)O(2) exposure, cause upregulation of the white-spotted flower chafer Protaetia brevitarsis (Coleoptera: Scarabaeidae) transferrin (PbTf) mRNA in the fat body and increases PbTf protein levels in the hemolymph. RNA interference (RNAi) treated PbTf reduction causes increased iron and H(2)O(2) levels in the hemolymph and results in induction of apoptotic cell death in the fat body during exposure to stress. The observed effects of PbTf RNAi suggest that PbTf inhibits stress-induced apoptosis by diminishing the Fenton reaction via the binding of iron, thus supporting an antioxidant role for PbTf in stress responses.
authors.affiliation: College of Natural Resources and Life Science, Dong-A University, Busan 604-714, South Korea.
authors.forename: Bo Yeon
authors.initials: BY
authors.lastname: Kim
authors.forename: Kwang Sik
authors.initials: KS
authors.lastname: Lee
authors.forename: Young Moo
authors.initials: YM
authors.lastname: Choo
authors.forename: Iksoo
authors.initials: I
authors.lastname: Kim
authors.forename: Yeon Ho
authors.initials: YH
authors.lastname: Je
authors.forename: Soo Dong
authors.initials: SD
authors.lastname: Woo
authors.forename: Sang Mong
authors.initials: SM
authors.lastname: Lee
authors.forename: Hyun Cheol
authors.initials: HC
authors.lastname: Park
authors.forename: Hung Dae
authors.initials: HD
authors.lastname: Sohn
authors.forename: Byung Rae
authors.initials: BR
authors.lastname: Jin
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000502:physiology*; D052982:Beauveria; D001517:Coleoptera / Q000254:growth & development / Q000378:metabolism* / Q000382:microbiology; D006458:Hemolymph / Q000378:metabolism; D006358:Hot Temperature; D006861:Hydrogen Peroxide / Q000494:pharmacology; D019476:Insect Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D007814:Larva / Q000187:drug effects / Q000378:metabolism / Q000382:microbiology; D018384:Oxidative Stress; D034622:RNA Interference; D014168:Transferrin / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*
chemical_list: D000975:Antioxidants; D019476:Insect Proteins; D014168:Transferrin; D006861:Hydrogen Peroxide