TY - JOUR A1 - Marelja, Zvonimir A1 - Leimkühler, Silke A1 - Missirlis, Fanis T1 - Iron sulfur and molybdenum cofactor enzymes regulate the drosophila life cycle by controlling cell metabolism JF - Frontiers in physiology N2 - Iron sulfur (Fe-S) clusters and the molybdenum cofactor (Moco) are present at enzyme sites, where the active metal facilitates electron transfer. Such enzyme systems are soluble in the mitochondrial matrix, cytosol and nucleus, or embedded in the inner mitochondrial membrane, but virtually absent from the cell secretory pathway. They are of ancient evolutionary origin supporting respiration, DNA replication, transcription, translation, the biosynthesis of steroids, heme, catabolism of purines, hydroxylation of xenobiotics, and cellular sulfur metabolism. Here, Fe-S cluster and Moco biosynthesis in Drosophila melanogaster is reviewed and the multiple biochemical and physiological functions of known Fe-S and Moco enzymes are described. We show that RNA interference of Mocs3 disrupts Moco biosynthesis and the circadian clock. Fe-S-dependent mitochondrial respiration is discussed in the context of germ line and somatic development, stem cell differentiation and aging. The subcellular compartmentalization of the Fe-S and Moco assembly machinery components and their connections to iron sensing mechanisms and intermediary metabolism are emphasized. A biochemically active Fe-S core complex of heterologously expressed fly Nfs1, Isd11, IscU, and human frataxin is presented. Based on the recent demonstration that copper displaces the Fe-S cluster of yeast and human ferredoxin, an explanation for why high dietary copper leads to cytoplasmic iron deficiency in flies is proposed. Another proposal that exosomes contribute to the transport of xanthine dehydrogenase from peripheral tissues to the eye pigment cells is put forward, where the Vps16a subunit of the HOPS complex may have a specialized role in concentrating this enzyme within pigment granules. Finally, we formulate a hypothesis that (i) mitochondrial superoxide mobilizes iron from the Fe-S clusters in aconitase and succinate dehydrogenase; (ii) increased iron transiently displaces manganese on superoxide dismutase, which may function as a mitochondrial iron sensor since it is inactivated by iron; (iii) with the Krebs cycle thus disrupted, citrate is exported to the cytosol for fatty acid synthesis, while succinyl-CoA and the iron are used for heme biosynthesis; (iv) as iron is used for heme biosynthesis its concentration in the matrix drops allowing for manganese to reactivate superoxide dismutase and Fe-S cluster biosynthesis to reestablish the Krebs cycle. KW - aldehyde oxidase KW - DNA polymerase KW - electron transport chain KW - ecdysone KW - iron regulatory protein KW - quiescent mitochondria KW - magnetoreceptor KW - mitoflashes Y1 - 2018 U6 - https://doi.org/10.3389/fphys.2018.00050 SN - 1664-042X VL - 9 PB - Frontiers Research Foundation CY - Lausanne ER - TY - GEN A1 - Marelja, Zvonimir A1 - Leimkühler, Silke A1 - Missirlis, Fanis T1 - Iron sulfur and molybdenum cofactor enzymes regulate the Drosophila life cycle by controlling cell metabolism T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Iron sulfur (Fe-S) clusters and the molybdenum cofactor (Moco) are present at enzyme sites, where the active metal facilitates electron transfer. Such enzyme systems are soluble in the mitochondrial matrix, cytosol and nucleus, or embedded in the inner mitochondrial membrane, but virtually absent from the cell secretory pathway. They are of ancient evolutionary origin supporting respiration, DNA replication, transcription, translation, the biosynthesis of steroids, heme, catabolism of purines, hydroxylation of xenobiotics, and cellular sulfur metabolism. Here, Fe-S cluster and Moco biosynthesis in Drosophila melanogaster is reviewed and the multiple biochemical and physiological functions of known Fe-S and Moco enzymes are described. We show that RNA interference of Mocs3 disrupts Moco biosynthesis and the circadian clock. Fe-S-dependent mitochondrial respiration is discussed in the context of germ line and somatic development, stem cell differentiation and aging. The subcellular compartmentalization of the Fe-S and Moco assembly machinery components and their connections to iron sensing mechanisms and intermediary metabolism are emphasized. A biochemically active Fe-S core complex of heterologously expressed fly Nfs1, Isd11, IscU, and human frataxin is presented. Based on the recent demonstration that copper displaces the Fe-S cluster of yeast and human ferredoxin, an explanation for why high dietary copper leads to cytoplasmic iron deficiency in flies is proposed. Another proposal that exosomes contribute to the transport of xanthine dehydrogenase from peripheral tissues to the eye pigment cells is put forward, where the Vps16a subunit of the HOPS complex may have a specialized role in concentrating this enzyme within pigment granules. Finally, we formulate a hypothesis that (i) mitochondrial superoxide mobilizes iron from the Fe-S clusters in aconitase and succinate dehydrogenase; (ii) increased iron transiently displaces manganese on superoxide dismutase, which may function as a mitochondrial iron sensor since it is inactivated by iron; (iii) with the Krebs cycle thus disrupted, citrate is exported to the cytosol for fatty acid synthesis, while succinyl-CoA and the iron are used for heme biosynthesis; (iv) as iron is used for heme biosynthesis its concentration in the matrix drops allowing for manganese to reactivate superoxide dismutase and Fe-S cluster biosynthesis to reestablish the Krebs cycle. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 925 KW - aldehyde oxidase KW - DNA polymerase KW - electron transport chain KW - ecdysone KW - iron regulatory protein KW - quiescent mitochondria KW - magnetoreceptor KW - mitoflashes Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-445670 SN - 1866-8372 IS - 925 ER - TY - JOUR A1 - Marelja, Zvonimir A1 - Dambowsky, Miriam A1 - Bolis, Marco A1 - Georgiou, Marina L. A1 - Garattini, Enrico A1 - Missirlis, Fanis A1 - Leimkühler, Silke T1 - The four aldehyde oxidases of Drosophila melanogaster have different gene expression patterns and enzyme substrate specificities JF - The journal of experimental biology N2 - In the genome of Drosophila melanogaster, four genes coding for aldehyde oxidases (AOX1-4) were identified on chromosome 3. Phylogenetic analysis showed that the AOX gene cluster evolved via independent duplication events in the vertebrate and invertebrate lineages. The functional role and the substrate specificity of the distinct Drosophila AOX enzymes is unknown. Two loss-of-function mutant alleles in this gene region, low pyridoxal oxidase (Po-lpo) and aldehyde oxidase-1 (Aldox-1(n1)) are associated with a phenotype characterized by undetectable AOX enzymatic activity. However, the genes involved and the corresponding mutations have not yet been identified. In this study we characterized the activities, substrate specificities and expression profiles of the four AOX enzymes in D. melanogaster. We show that the Po-lpo-associated phenotype is the consequence of a structural alteration of the AOX1 gene. We identified an 11-bp deletion in the Po-lpo allele, resulting in a frame-shift event, which removes the molybdenum cofactor domain of the encoded enzyme. Furthermore, we show that AOX2 activity is detectable only during metamorphosis and characterize a Minos-AOX2 insertion in this developmental gene that disrupts its activity. We demonstrate that the Aldox-1(n1) phenotype maps to the AOX3 gene and AOX4 activity is not detectable in our assays. KW - Aldehyde oxidase KW - Molybdoenzymes KW - Drosophila melanogaster KW - Gene duplication KW - Substrate specificities Y1 - 2014 U6 - https://doi.org/10.1242/jeb.102129 SN - 0022-0949 SN - 1477-9145 VL - 217 IS - 12 SP - 2201 EP - 2211 PB - Company of Biologists Limited CY - Cambridge ER -