title: Genetic link between heme oxygenase and the signaling pathway of DNA damage in Drosophila melanogaster.
abstract: Heme oxygenase (HO) is a rate-limiting step of heme degradation, which catalyzes the conversion of heme into biliverdin, iron, and CO. HO has been characterized in microorganisms, insects, plants, and mammals. The mammalian enzyme participates in adaptive and protective responses to oxidative stress and various inflammatory stimuli. The present study reports that eye imaginal disc-specific knockdown of the Drosophila HO homologue (dHO) conferred serious abnormal eye morphology in adults, resulting in the generation of reactive oxygen species and apoptosis in third-instar larvae. Oxidative stress frequently induces DNA lesions that are recognized by damage sensors, including ataxia-telangiectasia mutated (ATM) and ataxia-telangiectasia and rad3-related (ATR) proteins. The knockdown of dHO took place in G0/G1-arrested cells posterior to the morphogenetic furrow and thus prevented these cells from entering S-phase, with an increase in the level of histone H2A.V, a DNA damage marker. Moreover, the knockdown of dHO resulted in the enhancement of the rough eye phenotype in ATM-deficient flies or was lethal in ATR-deficient flies. These results indicate that dHO functions in control of the signal pathway of DNA damage. On the other hand, genetic crosses with a collection of Drosophila deficiency stocks allowed us to identify eight genomic regions, each deletion of which caused suppression of the rough eye phenotype induced by dHO knockdown. This information should facilitate the identification of HO regulators in Drosophila and clarification of the roles of HO in eye development.
authors.affiliation: Department of Applied Biology, Kyoto Institute of Technology.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ida
authors.forename: Osamu
authors.initials: O
authors.lastname: Suyari
authors.forename: Mai
authors.initials: M
authors.lastname: Shimamura
authors.forename: Tran
authors.initials: T
authors.lastname: Tien Tai
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Yamaguchi
authors.forename: Shigeru
authors.initials: S
authors.lastname: Taketani
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001973:Bromodeoxyuridine; D002453:Cell Cycle / Q000235:genetics / Q000502:physiology; D054910:Compound Eye, Arthropod / Q000002:abnormalities / Q000254:growth & development*; D003433:Crosses, Genetic; D004249:DNA Damage / Q000235:genetics* / Q000502:physiology; D004331:Drosophila melanogaster / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D055785:Gene Knockdown Techniques; D057809:HEK293 Cells; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D060227:Imaginal Discs / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure; D007814:Larva / Q000201:enzymology / Q000254:growth & development; D008855:Microscopy, Electron, Scanning; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D017382:Reactive Oxygen Species; D015398:Signal Transduction / Q000235:genetics* / Q000502:physiology
chemical_list: D034741:RNA, Small Interfering; D017382:Reactive Oxygen Species; D006419:Heme Oxygenase (Decyclizing); D001973:Bromodeoxyuridine