1
|
Shi Y, Zhang J, Luo K, Pan S, Shi H, Xiong L, Du S. The Roles of Iron and Ferroptosis in Human Chronic Diseases. Biochemistry 2023. [DOI: 10.5772/intechopen.108790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Ferroptosis, an iron-dependent novel type of cell death, has been characterized as an excessive accumulation of lipid peroxides and reactive oxygen species. A growing number of studies demonstrate that ferroptosis not only plays an important role in the pathogenesis and progression of chronic diseases, but also functions differently in different diseases. As a double-edged sword, activation of ferroptosis could potently inhibit tumor growth and increase sensitivity to chemotherapy and immunotherapy in various cancer settings. Therefore, the development of more efficacious ferroptosis agonists or inhibitors remains the mainstay of ferroptosis-targeting strategy for cancer therapeutics or cardiovascular and cerebrovascular diseases and neurodegenerative diseases therapeutics.
Collapse
|
2
|
Porras CA, Rouault TA. Iron Homeostasis in the CNS: An Overview of the Pathological Consequences of Iron Metabolism Disruption. Int J Mol Sci 2022; 23:ijms23094490. [PMID: 35562883 PMCID: PMC9104368 DOI: 10.3390/ijms23094490] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/14/2022] [Accepted: 04/17/2022] [Indexed: 11/21/2022] Open
Abstract
Iron homeostasis disruption has increasingly been implicated in various neurological disorders. In this review, we present an overview of our current understanding of iron metabolism in the central nervous system. We examine the consequences of both iron accumulation and deficiency in various disease contexts including neurodegenerative, neurodevelopmental, and neuropsychological disorders. The history of animal models of iron metabolism misregulation is also discussed followed by a comparison of three patients with a newly discovered neurodegenerative disorder caused by mutations in iron regulatory protein 2.
Collapse
|
3
|
Gladich I, Chen S, Yang H, Boucly A, Winter B, van Bokhoven JA, Ammann M, Artiglia L. Liquid-Gas Interface of Iron Aqueous Solutions and Fenton Reagents. J Phys Chem Lett 2022; 13:2994-3001. [PMID: 35344351 DOI: 10.1021/acs.jpclett.2c00380] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Fenton chemistry, involving the reaction between Fe2+ and hydrogen peroxide, is well-known due to its applications in the mineralization of extremely stable molecules. Different mechanisms, influenced by the reaction conditions and the solvation sphere of iron ions, influence the fate of such reactions. Despite the huge amount of effort spent investigating such processes, a complete understanding is still lacking. This work combines photoelectron spectroscopy and theoretical calculations to investigate the solvation and reactivity of Fe2+ and Fe3+ ions in aqueous solutions. The reaction with hydrogen peroxide, both in homogeneous Fenton reagents and at the liquid-vapor interface, illustrates that both ions are homogeneously distributed in solutions and exhibit an asymmetric octahedral coordination to water in the case of Fe2+. No indications of differences in the reaction mechanism between the liquid-vapor interface and the bulk of the solutions have been found, suggesting that Fe3+ and hydroxyl radicals are the only intermediates.
Collapse
Affiliation(s)
- Ivan Gladich
- European Centre for Living Technology (ECLT), Dorsoduro, Calle Crosera, 30123 Venice, Italy
| | - Shuzhen Chen
- Laboratory of Environmental Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
- Institute of Atmospheric and Climate Sciences, ETH Zürich, 8092 Zürich, Switzerland
| | - Huanyu Yang
- Laboratory of Environmental Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
- Institute of Atmospheric and Climate Sciences, ETH Zürich, 8092 Zürich, Switzerland
| | - Anthony Boucly
- Laboratory of Environmental Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Bernd Winter
- Molecular Physics Department, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Jeroen A van Bokhoven
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
- Institute for Chemical and Bioengineering, ETH Zürich, 8092 Zürich, Switzerland
| | - Markus Ammann
- Laboratory of Environmental Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
- Institute of Atmospheric and Climate Sciences, ETH Zürich, 8092 Zürich, Switzerland
| | - Luca Artiglia
- Laboratory of Environmental Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232 Villigen, Switzerland
| |
Collapse
|
4
|
Ogłuszka M, Lipiński P, Starzyński RR. Interaction between iron and omega-3 fatty acids metabolisms: where is the cross-link? Crit Rev Food Sci Nutr 2020; 62:3002-3022. [DOI: 10.1080/10408398.2020.1862047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Magdalena Ogłuszka
- Department of Genomics, Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Jastrzębiec, Poland
| | - Paweł Lipiński
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Jastrzębiec, Poland
| | - Rafał Radosław Starzyński
- Department of Molecular Biology, Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Jastrzębiec, Poland
| |
Collapse
|
5
|
Senoura T, Kobayashi T, An G, Nakanishi H, Nishizawa NK. Defects in the rice aconitase-encoding OsACO1 gene alter iron homeostasis. PLANT MOLECULAR BIOLOGY 2020; 104:629-645. [PMID: 32909184 DOI: 10.1007/s11103-020-01065-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 08/30/2020] [Indexed: 05/16/2023]
Abstract
Rice aconitase gene OsACO1 is involved in the iron deficiency-signaling pathway for the expression of iron deficiency-inducible genes, either thorough enzyme activity or possible specific RNA binding for post-transcriptional regulation. Iron (Fe) is an essential element for virtually all living organisms. When plants are deficient in Fe, Fe acquisition systems are activated to maintain Fe homeostasis, and this regulation is mainly executed at the gene transcription level. Many molecules responsible for Fe uptake, translocation, and storage in plants have been identified and characterized. However, how plants sense Fe status within cells and then induce a transcriptional response is still unclear. In the present study, we found that knockdown of the OsACO1 gene, which encodes an aconitase in rice, leads to the down-regulation of selected Fe deficiency-inducible genes involved in Fe uptake and translocation in roots, and a decrease in Fe concentration in leaves, even when grown under Fe-sufficient conditions. OsACO1 knockdown plants showed a delayed transcriptional response to Fe deficiency compared to wild-type plants. In contrast, overexpression of OsACO1 resulted in the opposite effects. These results suggest that OsACO1 is situated upstream of the Fe deficiency-signaling pathway. Furthermore, we found that the OsACO1 protein potentially has RNA-binding activity. In vitro screening of RNA interactions with OsACO1 revealed that RNA potentially forms a unique stem-loop structure that interacts with OsACO1 via a conserved GGUGG motif within the loop structure. These results suggest that OsACO1 regulate Fe deficiency response either thorough enzyme activity catalyzing isomerization of citrate, or specific RNA binding for post-transcriptional regulation.
Collapse
Affiliation(s)
- Takeshi Senoura
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, 1-308 Suematsu, Nonoichi, Ishikawa, 921-8836, Japan
| | - Takanori Kobayashi
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, 1-308 Suematsu, Nonoichi, Ishikawa, 921-8836, Japan.
| | - Gynheung An
- Crop Biotech Institute and Graduate School of Biotechnology, Kyung Hee University, Yongin, 17104, Korea
| | - Hiromi Nakanishi
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Naoko K Nishizawa
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, 1-308 Suematsu, Nonoichi, Ishikawa, 921-8836, Japan.
| |
Collapse
|
6
|
Alvarez‐Carreño C, Alva V, Becerra A, Lazcano A. Structure, function and evolution of the hemerythrin-like domain superfamily. Protein Sci 2018; 27:848-860. [PMID: 29330894 PMCID: PMC5866928 DOI: 10.1002/pro.3374] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 01/09/2018] [Accepted: 01/10/2018] [Indexed: 01/22/2023]
Abstract
Hemerythrin-like proteins have generally been studied for their ability to reversibly bind oxygen through their binuclear nonheme iron centers. However, in recent years, it has become increasingly evident that some members of the hemerythrin-like superfamily also participate in many other biological processes. For instance, the binuclear nonheme iron site of YtfE, a hemerythrin-like protein involved in the repair of iron centers in Escherichia coli, catalyzes the reduction of nitric oxide to nitrous oxide, and the human F-box/LRR-repeat protein 5, which contains a hemerythrin-like domain, is involved in intracellular iron homeostasis. Furthermore, structural data on hemerythrin-like domains from two proteins of unknown function, PF0695 from Pyrococcus furiosus and NMB1532 from Neisseria meningitidis, show that the cation-binding sites, typical of hemerythrin, can be absent or be occupied by metal ions other than iron. To systematically investigate this functional and structural diversity of the hemerythrin-like superfamily, we have collected hemerythrin-like sequences from a database comprising fully sequenced proteomes and generated a cluster map based on their all-against-all pairwise sequence similarity. Our results show that the hemerythrin-like superfamily comprises a large number of protein families which can be classified into three broad groups on the basis of their cation-coordinating residues: (a) signal-transduction and oxygen-carrier hemerythrins (H-HxxxE-HxxxH-HxxxxD); (b) hemerythrin-like (H-HxxxE-H-HxxxE); and, (c) metazoan F-box proteins (H-HExxE-H-HxxxE). Interestingly, all but two hemerythrin-like families exhibit internal sequence and structural symmetry, suggesting that a duplication event may have led to the origin of the hemerythrin domain.
Collapse
Affiliation(s)
- Claudia Alvarez‐Carreño
- Facultad de Ciencias, Universidad Nacional Autónoma de México, Apdo. Postal 70‐407, Cd. UniversitariaMexico City04510Mexico
| | - Vikram Alva
- Department of Protein EvolutionMax Planck Institute for Developmental BiologyTübingen72076Germany
| | - Arturo Becerra
- Facultad de Ciencias, Universidad Nacional Autónoma de México, Apdo. Postal 70‐407, Cd. UniversitariaMexico City04510Mexico
| | - Antonio Lazcano
- Facultad de Ciencias, Universidad Nacional Autónoma de México, Apdo. Postal 70‐407, Cd. UniversitariaMexico City04510Mexico
- Miembro de El Colegio NacionalMexico
| |
Collapse
|
7
|
Liang H, Huang H, Tan PZ, Liu Y, Nie JH, Zhang YT, Zhang KL, Diao Y, He Q, Hou BY, Zhao TT, Li YZ, Lv GX, Lee KY, Gao X, Zhou LY. Effect of iron on cholesterol 7α-hydroxylase expression in alcohol-induced hepatic steatosis in mice. J Lipid Res 2017; 58:1548-1560. [PMID: 28536109 DOI: 10.1194/jlr.m074534] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 05/19/2017] [Indexed: 12/17/2022] Open
Abstract
Both iron and lipids are involved in the progression of alcoholic fatty liver disease (AFLD), but the interaction between iron and lipids in AFLD is unclear. Here, we tested the hypothesis that iron regulates the expression of genes involved in lipid metabolism through iron regulatory proteins (IRPs), which interact with the iron-responsive elements (IREs) in the untranslated regions (UTRs) of genes, resulting in lipid accumulation. Using "RNA structure software", we predicted the mRNA secondary structures of more than 100 genes involved in lipid metabolism to investigate whether the IRE structure exists in novel mRNAs. Cholesterol 7α-hydroxylase (Cyp7a1) has an IRE-like stem-loop, a noncanonical IRE structure, in its 3'-UTR. Cyp7a1 expression can be regulated by in vivo and in vitro iron treatment. In addition, the noncanonical IRE motif can efficiently bind both to IRP1 and IRP2. The results indicate that hepatic iron overloading in AFLD mice decreased Cyp7a1 expression and resulted in cholesterol accumulation, providing a new mechanism of iron-regulated gene transcription and translation through the interaction between iron and a noncanonical IRE structure in Cyp7a1 mRNA. This finding has significant implications in studying a proposed mechanism for the regulation of cholesterol homeostasis by an Fe/IRP/noncanonical IRE axis.
Collapse
Affiliation(s)
- Huan Liang
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China; Department of Clinical Laboratory, Harbin Medical University Cancer Hospital, Harbin, China
| | - Hui Huang
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China
| | - Pei-Zhu Tan
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China; Experiment Center of Biotechnology, Harbin Medical University, Harbin, China
| | - Ying Liu
- Department of Gastroenterology, Heilongjiang Province Hospital, Harbin, China
| | - Jun-Hui Nie
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China
| | - Yi-Tong Zhang
- Department of Neurology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Kai-Li Zhang
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China
| | - Yan Diao
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China
| | - Qi He
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China
| | - Bao-Yu Hou
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China
| | - Ting-Ting Zhao
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China
| | - Yan-Ze Li
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China.
| | - Gui-Xiang Lv
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China
| | - Ki-Young Lee
- Department of Cell Biology and Anatomy, Arnie Charbonneau Cancer Institute, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Xu Gao
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China.
| | - Ling-Yun Zhou
- Department of Biochemistry and Molecular Biology Harbin Medical University, Harbin, China; Translational Medicine Center of Northern China, Harbin, China
| |
Collapse
|
8
|
Smith SR, Gillard JTF, Kustka AB, McCrow JP, Badger JH, Zheng H, New AM, Dupont CL, Obata T, Fernie AR, Allen AE. Transcriptional Orchestration of the Global Cellular Response of a Model Pennate Diatom to Diel Light Cycling under Iron Limitation. PLoS Genet 2016; 12:e1006490. [PMID: 27973599 PMCID: PMC5156380 DOI: 10.1371/journal.pgen.1006490] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 11/16/2016] [Indexed: 11/23/2022] Open
Abstract
Environmental fluctuations affect distribution, growth and abundance of diatoms in nature, with iron (Fe) availability playing a central role. Studies on the response of diatoms to low Fe have either utilized continuous (24 hr) illumination or sampled a single time of day, missing any temporal dynamics. We profiled the physiology, metabolite composition, and global transcripts of the pennate diatom Phaeodactylum tricornutum during steady-state growth at low, intermediate, and high levels of dissolved Fe over light:dark cycles, to better understand fundamental aspects of genetic control of physiological acclimation to growth under Fe-limitation. We greatly expand the catalog of genes involved in the low Fe response, highlighting the importance of intracellular trafficking in Fe-limited diatoms. P. tricornutum exhibited transcriptomic hallmarks of slowed growth leading to prolonged periods of cell division/silica deposition, which could impact biogeochemical carbon sequestration in Fe-limited regions. Light harvesting and ribosome biogenesis transcripts were generally reduced under low Fe while transcript levels for genes putatively involved in the acquisition and recycling of Fe were increased. We also noted shifts in expression towards increased synthesis and catabolism of branched chain amino acids in P. tricornutum grown at low Fe whereas expression of genes involved in central core metabolism were relatively unaffected, indicating that essential cellular function is protected. Beyond the response of P. tricornutum to low Fe, we observed major coordinated shifts in transcript control of primary and intermediate metabolism over light:dark cycles which contribute to a new view of the significance of distinctive diatom pathways, such as mitochondrial glycolysis and the ornithine-urea cycle. This study provides new insight into transcriptional modulation of diatom physiology and metabolism across light:dark cycles in response to Fe availability, providing mechanistic understanding for the ability of diatoms to remain metabolically poised to respond quickly to Fe input and revealing strategies underlying their ecological success. Oceanic diatoms live in constantly fluctuating environments to which they must adapt in order to survive. During sunlit hours, photosynthesis occurs allowing diatoms to store energy used at night to sustain energy demands. Cellular and molecular mechanisms for regulation of phytoplankton growth are important to understand because of their environmental roles at the base of food webs and in regulating carbon flux out of the atmosphere. In ocean ecosystems, the availability of iron (Fe) commonly limits phytoplankton growth and diatoms typically outcompete other phytoplankton when Fe is added, indicating they have adaptations allowing them to both survive at low Fe and rapidly respond to Fe additions. These adaptations may be unique depending on isolation from coastal or oceanic locations. To identify adaptive strategies, we characterized the response of a model diatom, Phaeodactylum tricornutum, to limiting Fe conditions over day:night cycles using a combination of gene expression analyses, metabolite, and physiology measurements. Major coordinated shifts in metabolism and growth were documented over diel cycles, with peak expression of low Fe expressed genes in the dark phase. Diatoms respond to limiting Fe by increasing Fe acquisition, while decreasing growth rate through slowed cell cycle progression, reduced energy acquisition, and subtle metabolic remodeling.
Collapse
Affiliation(s)
- Sarah R. Smith
- Integrative Oceanography Division, Scripps Institution of Oceanography, UC San Diego, La Jolla, California, United States of America
- J. Craig Venter Institute, La Jolla, California, United States of America
| | - Jeroen T. F. Gillard
- J. Craig Venter Institute, La Jolla, California, United States of America
- Department of Biology, CSU Bakersfield, Bakersfield, California, United States of America
| | - Adam B. Kustka
- Department of Earth and Environmental Sciences, Rutgers University, Newark, New Jersey, United States of America
| | - John P. McCrow
- J. Craig Venter Institute, La Jolla, California, United States of America
| | - Jonathan H. Badger
- J. Craig Venter Institute, La Jolla, California, United States of America
| | - Hong Zheng
- J. Craig Venter Institute, La Jolla, California, United States of America
| | - Ashley M. New
- Department of Earth and Environmental Sciences, Rutgers University, Newark, New Jersey, United States of America
| | - Chris L. Dupont
- J. Craig Venter Institute, La Jolla, California, United States of America
| | - Toshihiro Obata
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam, Germany
| | - Alisdair R. Fernie
- Max-Planck-Institut für Molekulare Pflanzenphysiologie, Potsdam, Germany
| | - Andrew E. Allen
- Integrative Oceanography Division, Scripps Institution of Oceanography, UC San Diego, La Jolla, California, United States of America
- J. Craig Venter Institute, La Jolla, California, United States of America
- * E-mail: ,
| |
Collapse
|
9
|
Molecular Evolution of the Oxygen-Binding Hemerythrin Domain. PLoS One 2016; 11:e0157904. [PMID: 27336621 PMCID: PMC4919030 DOI: 10.1371/journal.pone.0157904] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 06/07/2016] [Indexed: 11/30/2022] Open
Abstract
Background The evolution of oxygenic photosynthesis during Precambrian times entailed the diversification of strategies minimizing reactive oxygen species-associated damage. Four families of oxygen-carrier proteins (hemoglobin, hemerythrin and the two non-homologous families of arthropodan and molluscan hemocyanins) are known to have evolved independently the capacity to bind oxygen reversibly, providing cells with strategies to cope with the evolutionary pressure of oxygen accumulation. Oxygen-binding hemerythrin was first studied in marine invertebrates but further research has made it clear that it is present in the three domains of life, strongly suggesting that its origin predated the emergence of eukaryotes. Results Oxygen-binding hemerythrins are a monophyletic sub-group of the hemerythrin/HHE (histidine, histidine, glutamic acid) cation-binding domain. Oxygen-binding hemerythrin homologs were unambiguously identified in 367/2236 bacterial, 21/150 archaeal and 4/135 eukaryotic genomes. Overall, oxygen-binding hemerythrin homologues were found in the same proportion as single-domain and as long protein sequences. The associated functions of protein domains in long hemerythrin sequences can be classified in three major groups: signal transduction, phosphorelay response regulation, and protein binding. This suggests that in many organisms the reversible oxygen-binding capacity was incorporated in signaling pathways. A maximum-likelihood tree of oxygen-binding hemerythrin homologues revealed a complex evolutionary history in which lateral gene transfer, duplications and gene losses appear to have played an important role. Conclusions Hemerythrin is an ancient protein domain with a complex evolutionary history. The distinctive iron-binding coordination site of oxygen-binding hemerythrins evolved first in prokaryotes, very likely prior to the divergence of Firmicutes and Proteobacteria, and spread into many bacterial, archaeal and eukaryotic species. The later evolution of the oxygen-binding hemerythrin domain in both prokaryotes and eukaryotes led to a wide variety of functions, ranging from protection against oxidative damage in anaerobic and microaerophilic organisms, to oxygen supplying to particular enzymes and pathways in aerobic and facultative species.
Collapse
|
10
|
Abstract
PURPOSE OF REVIEW Iron homeostasis and erythropoiesis regulate each other to ensure optimal delivery of oxygen and iron to cells and tissues. Defining the mechanisms of this crosstalk is important for understanding the pathogenesis of common conditions associated with disordered iron metabolism and erythropoiesis. RECENT FINDINGS Stress erythropoiesis causes suppression of hepcidin to increase iron availability for hemoglobin synthesis. The erythroid hormone erythroferrone (ERFE) was identified as the mediator of this process. ERFE and additional candidates (TWSG1 and GDF15) may also mediate hepcidin suppression in ineffective erythropoiesis. Several mechanisms by which iron regulates erythropoiesis were also recently identified. Iron deficiency suppresses erythropoietin production via the IRP1-HIF2α axis to prevent excessive iron usage by erythropoiesis during systemic iron restriction. Iron restriction also directly impairs erythroid maturation by inhibiting aconitase, and this can be reversed by the administration of the aconitase product isocitrate. Another novel target is GDF11, which is thought to autoinhibit erythroid maturation. GDF11 traps show promising pharmacologic activity in models of both ineffective erythropoiesis and iron-restricted anemia. SUMMARY This review summarizes exciting advances in understanding the mechanisms of iron and erythropoietic regulation, and development of novel therapeutic tools for disorders resulting from dysregulation of iron metabolism or erythropoiesis.
Collapse
|
11
|
Jancsó Z, Bódi N, Borsos B, Fekete É, Hermesz E. Gut region-specific accumulation of reactive oxygen species leads to regionally distinct activation of antioxidant and apoptotic marker molecules in rats with STZ-induced diabetes. Int J Biochem Cell Biol 2015; 62:125-31. [PMID: 25794426 DOI: 10.1016/j.biocel.2015.03.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/03/2015] [Accepted: 03/09/2015] [Indexed: 02/07/2023]
Abstract
UNLABELLED The aim of this study was to seek possible links between the regionality along the digestive tract and the accumulation of reactive oxygen species, the effectiveness of the antioxidant defense system and the sensitivity to the types of demise in different gut regions of rats with streptozotocin-induced diabetes. Significant changes were observed in the oxidative status and in the activity of the antioxidant defense system in the diabetic colon; the peroxynitrite production was doubled, the level of hemoxygenase-2 protein was increased 11-fold and the expression of anti-apoptotic bcl-2 was also increased. The segment-specific vulnerability of the gastrointestinal tract induced by hyperglycemia was also confirmed by electron microscopy, demonstrating the presence of severe necrosis in the colon of the diabetic rats. No remarkable histopathological alterations were seen in the duodenum of the diabetic animals and there were likewise no significant changes in the production of peroxynitrite in their duodenum, whereas the level of the free radical scavenger metallothionein-2 was increased ∼300-fold. CONCLUSION The spatially restricted vulnerability observed along the digestive tract could originate from a high level of oxidative stress via peroxynitrite production.
Collapse
Affiliation(s)
- Zsanett Jancsó
- Department of Biochemistry and Molecular Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Nikolett Bódi
- Department of Physiology, Anatomy and Neuroscience, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Barbara Borsos
- Department of Biochemistry and Molecular Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Éva Fekete
- Department of Physiology, Anatomy and Neuroscience, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Edit Hermesz
- Department of Biochemistry and Molecular Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary.
| |
Collapse
|
12
|
Ghosh MC, Zhang DL, Rouault TA. Iron misregulation and neurodegenerative disease in mouse models that lack iron regulatory proteins. Neurobiol Dis 2015; 81:66-75. [PMID: 25771171 DOI: 10.1016/j.nbd.2015.02.026] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Revised: 01/14/2015] [Accepted: 02/03/2015] [Indexed: 01/01/2023] Open
Abstract
Iron regulatory proteins 1 and 2 (IRP1 and IRP2) are two cytosolic proteins that maintain cellular iron homeostasis by binding to RNA stem loops known as iron responsive elements (IREs) that are found in the untranslated regions of target mRNAs that encode proteins involved in iron metabolism. IRPs modify the expression of iron metabolism genes, and global and tissue-specific knockout mice have been made to evaluate the physiological significance of these iron regulatory proteins (Irps). Here, we will discuss the results of the studies that have been performed with mice engineered to lack the expression of one or both Irps and made in different strains using different methodologies. Both Irp1 and Irp2 knockout mice are viable, but the double knockout (Irp1(-/-)Irp2(-/-)) mice die before birth, indicating that these Irps play a crucial role in maintaining iron homeostasis. Irp1(-/-) mice develop polycythemia and pulmonary hypertension, and when these mice are challenged with a low iron diet, they die early of abdominal hemorrhages, suggesting that Irp1 plays an essential role in erythropoiesis and in the pulmonary and cardiovascular systems. Irp2(-/-) mice develop microcytic anemia, erythropoietic protoporphyria and a progressive neurological disorder, indicating that Irp2 has important functions in the nervous system and erythropoietic homeostasis. Several excellent review articles have recently been published on Irp knockout mice that mainly focus on Irp1(-/-) mice (referenced in the introduction). In this review, we will briefly describe the phenotypes and physiological implications of Irp1(-/-) mice and discuss the phenotypes observed for Irp2(-/-) mice in detail with a particular emphasis on the neurological problems of these mice.
Collapse
Affiliation(s)
- Manik C Ghosh
- Section on Human Iron Metabolism, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - De-Liang Zhang
- Section on Human Iron Metabolism, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Tracey A Rouault
- Section on Human Iron Metabolism, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
| |
Collapse
|
13
|
Hsu HM, Lee Y, Hsu PH, Liu HW, Chu CH, Chou YW, Chen YR, Chen SH, Tai JH. Signal transduction triggered by iron to induce the nuclear importation of a Myb3 transcription factor in the parasitic protozoan Trichomonas vaginalis. J Biol Chem 2014; 289:29334-49. [PMID: 25183012 DOI: 10.1074/jbc.m114.599498] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Iron was previously shown to induce rapid nuclear translocation of a Myb3 transcription factor in the protozoan parasite, Trichomonas vaginalis. In the present study, iron was found to induce a transient increase in cellular cAMP, followed by the nuclear influx of Myb3, whereas the latter was also induced by 8-bromo-cyclic AMP. Iron-inducible cAMP production and nuclear influx of Myb3 were inhibited by suramin and SQ22536, respective inhibitors of the Gα subunit of heterotrimeric G proteins and adenylyl cyclases. In contrast, the nuclear influx of Myb3 induced by iron or 8-bromo-cAMP was delayed or inhibited, respectively, by H89, the inhibitor of protein kinase A. Using liquid chromatography-coupled tandem mass spectrometry, Thr(156) and Lys(143) in Myb3 were found to be phosphorylated and ubiquitinated, respectively. These modifications were induced by iron and inhibited by H89, as shown by immunoprecipitation-coupled Western blotting. Iron-inducible ubiquitination and nuclear influx were aborted in T156A and K143R, but T156D was constitutively ubiquitinated and persistently localized to the nucleus. Myb3 was phosphorylated in vitro by the catalytic subunit of a T. vaginalis protein kinase A, TvPKAc. A transient interaction between TvPKAc and Myb3 and the phosphorylation of both proteins were induced in the parasite shortly after iron or 8-bromo-cAMP treatment. Together, these observations suggest that iron may induce production of cAMP and activation of TvPKAc, which then induces the phosphorylation of Myb3 and subsequent ubiquitination for accelerated nuclear influx. It is conceivable that iron probably exerts a much broader impact on the physiology of the parasite than previously thought to encounter environmental changes.
Collapse
Affiliation(s)
- Hong-Ming Hsu
- From the Division of Infectious Diseases, Institute of Biomedical Sciences and
| | - Yu Lee
- From the Division of Infectious Diseases, Institute of Biomedical Sciences and
| | - Pang-Hung Hsu
- the Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelun 20224, Taiwan, and
| | - Hsing-Wei Liu
- From the Division of Infectious Diseases, Institute of Biomedical Sciences and
| | - Chien-Hsin Chu
- From the Division of Infectious Diseases, Institute of Biomedical Sciences and
| | - Ya-Wen Chou
- Research Center of Agriculture and Biotechnology, Academia Sinica, Taipei 11529, Taiwan
| | - Yet-Ran Chen
- Research Center of Agriculture and Biotechnology, Academia Sinica, Taipei 11529, Taiwan
| | - Shu-Hui Chen
- the Department of Chemistry, National Chen Kung University, Tainan 70101, Taiwan
| | - Jung-Hsiang Tai
- From the Division of Infectious Diseases, Institute of Biomedical Sciences and
| |
Collapse
|
14
|
Iron-binding haemerythrin RING ubiquitin ligases regulate plant iron responses and accumulation. Nat Commun 2014; 4:2792. [PMID: 24253678 PMCID: PMC3905729 DOI: 10.1038/ncomms3792] [Citation(s) in RCA: 166] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 10/18/2013] [Indexed: 01/04/2023] Open
Abstract
Iron is essential for most living organisms. Plants transcriptionally induce genes involved in iron acquisition under conditions of low iron availability, but the nature of the deficiency signal and its sensors are unknown. Here we report the identification of new iron regulators in rice, designated Oryza sativaHaemerythrin motif-containing Really Interesting New Gene (RING)- and Zinc-finger protein 1 (OsHRZ1) and OsHRZ2. OsHRZ1, OsHRZ2 and their Arabidopsis homologue BRUTUS bind iron and zinc, and possess ubiquitination activity. OsHRZ1 and OsHRZ2 are susceptible to degradation in roots irrespective of iron conditions. OsHRZ-knockdown plants exhibit substantial tolerance to iron deficiency, and accumulate more iron in their shoots and grains irrespective of soil iron conditions. The expression of iron deficiency-inducible genes involved in iron utilization is enhanced in OsHRZ-knockdown plants, mostly under iron-sufficient conditions. These results suggest that OsHRZ1 and OsHRZ2 are iron-binding sensors that negatively regulate iron acquisition under conditions of iron sufficiency. Plants activate a gene transcription response under low iron conditions but how they sense insufficient iron levels is unclear. In this study, Kobayashi et al. identify two iron-binding proteins that possess ubiquitin ligase activity and are negative regulators of the iron deficiency response.
Collapse
|
15
|
Zhang DL, Ghosh MC, Rouault TA. The physiological functions of iron regulatory proteins in iron homeostasis - an update. Front Pharmacol 2014; 5:124. [PMID: 24982634 PMCID: PMC4056636 DOI: 10.3389/fphar.2014.00124] [Citation(s) in RCA: 146] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 05/10/2014] [Indexed: 01/15/2023] Open
Abstract
Iron regulatory proteins (IRPs) regulate the expression of genes involved in iron metabolism by binding to RNA stem-loop structures known as iron responsive elements (IREs) in target mRNAs. IRP binding inhibits the translation of mRNAs that contain an IRE in the 5′untranslated region of the transcripts, and increases the stability of mRNAs that contain IREs in the 3′untranslated region of transcripts. By these mechanisms, IRPs increase cellular iron absorption and decrease storage and export of iron to maintain an optimal intracellular iron balance. There are two members of the mammalian IRP protein family, IRP1 and IRP2, and they have redundant functions as evidenced by the embryonic lethality of the mice that completely lack IRP expression (Irp1-/-/Irp2-/- mice), which contrasts with the fact that Irp1-/- and Irp2-/- mice are viable. In addition, Irp2-/- mice also display neurodegenerative symptoms and microcytic hypochromic anemia, suggesting that IRP2 function predominates in the nervous system and erythropoietic homeostasis. Though the physiological significance of IRP1 had been unclear since Irp1-/- animals were first assessed in the early 1990s, recent studies indicate that IRP1 plays an essential function in orchestrating the balance between erythropoiesis and bodily iron homeostasis. Additionally, Irp1-/- mice develop pulmonary hypertension, and they experience sudden death when maintained on an iron-deficient diet, indicating that IRP1 has a critical role in the pulmonary and cardiovascular systems. This review summarizes recent progress that has been made in understanding the physiological roles of IRP1 and IRP2, and further discusses the implications for clinical research on patients with idiopathic polycythemia, pulmonary hypertension, and neurodegeneration.
Collapse
Affiliation(s)
- De-Liang Zhang
- Molecular Medicine Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institute of Health Bethesda, MD, USA
| | - Manik C Ghosh
- Molecular Medicine Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institute of Health Bethesda, MD, USA
| | - Tracey A Rouault
- Molecular Medicine Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institute of Health Bethesda, MD, USA
| |
Collapse
|
16
|
Chung J, Anderson SA, Gwynn B, Deck KM, Chen MJ, Langer NB, Shaw GC, Huston NC, Boyer LF, Datta S, Paradkar PN, Li L, Wei Z, Lambert AJ, Sahr K, Wittig JG, Chen W, Lu W, Galy B, Schlaeger TM, Hentze MW, Ward DM, Kaplan J, Eisenstein RS, Peters LL, Paw BH. Iron regulatory protein-1 protects against mitoferrin-1-deficient porphyria. J Biol Chem 2014; 289:7835-43. [PMID: 24509859 DOI: 10.1074/jbc.m114.547778] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Mitochondrial iron is essential for the biosynthesis of heme and iron-sulfur ([Fe-S]) clusters in mammalian cells. In developing erythrocytes, iron is imported into the mitochondria by MFRN1 (mitoferrin-1, SLC25A37). Although loss of MFRN1 in zebrafish and mice leads to profound anemia, mutant animals showed no overt signs of porphyria, suggesting that mitochondrial iron deficiency does not result in an accumulation of protoporphyrins. Here, we developed a gene trap model to provide in vitro and in vivo evidence that iron regulatory protein-1 (IRP1) inhibits protoporphyrin accumulation. Mfrn1(+/gt);Irp1(-/-) erythroid cells exhibit a significant increase in protoporphyrin levels. IRP1 attenuates protoporphyrin biosynthesis by binding to the 5'-iron response element (IRE) of alas2 mRNA, inhibiting its translation. Ectopic expression of alas2 harboring a mutant IRE, preventing IRP1 binding, in Mfrn1(gt/gt) cells mimics Irp1 deficiency. Together, our data support a model whereby impaired mitochondrial [Fe-S] cluster biogenesis in Mfrn1(gt/gt) cells results in elevated IRP1 RNA-binding that attenuates ALAS2 mRNA translation and protoporphyrin accumulation.
Collapse
Affiliation(s)
- Jacky Chung
- From the Division of Hematology, Brigham and Women's Hospital; Division of Hematology-Oncology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Abstract
In a fundamental process throughout nature, reduced iron unleashes the oxidative power of hydrogen peroxide into reactive intermediates. However, notwithstanding much work, the mechanism by which Fe(2+) catalyzes H2O2 oxidations and the identity of the participating intermediates remain controversial. Here we report the prompt formation of O=Fe(IV)Cl3(-) and chloride-bridged di-iron O=Fe(IV) · Cl · Fe(II)Cl4(-) and O=Fe(IV) · Cl · Fe(III)Cl5(-) ferryl species, in addition to Fe(III)Cl4(-), on the surface of aqueous FeCl2 microjets exposed to gaseous H2O2 or O3 beams for <50 μs. The unambiguous identification of such species in situ via online electrospray mass spectrometry let us investigate their individual dependences on Fe(2+), H2O2, O3, and H(+) concentrations, and their responses to tert-butanol (an · OH scavenger) and DMSO (an O-atom acceptor) cosolutes. We found that (i) mass spectra are not affected by excess tert-butanol, i.e., the detected species are primary products whose formation does not involve · OH radicals, and (ii) the di-iron ferryls, but not O=Fe(IV)Cl3(-), can be fully quenched by DMSO under present conditions. We infer that interfacial Fe(H2O)n(2+) ions react with H2O2 and O3 >10(3) times faster than Fe(H2O)6(2+) in bulk water via a process that favors inner-sphere two-electron O-atom over outer-sphere one-electron transfers. The higher reactivity of di-iron ferryls vs. O=Fe(IV)Cl3(-) as O-atom donors implicates the electronic coupling of mixed-valence iron centers in the weakening of the Fe(IV)-O bond in poly-iron ferryl species.
Collapse
Affiliation(s)
- Shinichi Enami
- The Hakubi Center for Advanced Research, Kyoto University, Kyoto 606-8302, Japan
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan
- Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency, Kawaguchi 332-0012, Japan
| | - Yosuke Sakamoto
- Faculty of Environmental Earth Science, Hokkaido University, Sapporo 060-0610, Japan; and
| | - Agustín J. Colussi
- Linde Center for Global Environmental Science, California Institute of Technology, CA 91125
| |
Collapse
|
18
|
Wu JR, Yuan LX, Ma ZG, Chen XX, Gu L, Gao J. GDF15-mediated upregulation of ferroportin plays a key role in the development of hyperferritinemia in children with hemophagocytic lymphohistiocytosis. Pediatr Blood Cancer 2013; 60:940-5. [PMID: 23335088 DOI: 10.1002/pbc.24373] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Accepted: 09/25/2012] [Indexed: 01/08/2023]
Abstract
BACKGROUND Growth differentiation factor 15 (GDF15), a divergent TGFβ superfamily, has recently been implicated in the modulation of iron homeostasis, acting as an upstream negative regulator of hepcidin, the key iron regulatory hormone produced primarily by hepatocytes. However, little is known about possible roles that GDF15 might play in the regulation of iron homeostasis and development of hyperferritinemia in children with hemophagocytic lymphohistiocytosis (HLH). PROCEDURES We compared serum GDF15 level and mRNA expressions of GDF15 and key molecules of iron metabolism, and made correlations between their expressions in children with HLH and control children. RESULTS Serum GDF15 level was remarkably higher in HLH group than that in controls, with median serum concentration of 1,700 and 260 pg/ml, respectively (P < 0.001). In addition, GDF15 mRNA was significantly upregulated but independent of hypoxia-inducible factor-mediated oxygen signaling pathway. More importantly, GDF15 induction was positively correlated to upregulation of ferroportin, the only cellular iron exporter, and to upregulation of ferritin heavy chain. CONCLUSIONS Our study suggests that GDF15 induction helps suppress further activation of macrophages in stressful physiologic states as HLH, and is intimately implicated in the development of hyperferritinemia by modulating the hepcidin-ferroportin axis, resulting in enhanced ferroportin-mediated iron efflux.
Collapse
Affiliation(s)
- Jian-Rong Wu
- Hematology and Oncology Unit, Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
| | | | | | | | | | | |
Collapse
|
19
|
Drengstig T, Jolma IW, Ni XY, Thorsen K, Xu XM, Ruoff P. A basic set of homeostatic controller motifs. Biophys J 2013. [PMID: 23199928 DOI: 10.1016/j.bpj.2012.09.033] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Adaptation and homeostasis are essential properties of all living systems. However, our knowledge about the reaction kinetic mechanisms leading to robust homeostatic behavior in the presence of environmental perturbations is still poor. Here, we describe, and provide physiological examples of, a set of two-component controller motifs that show robust homeostasis. This basic set of controller motifs, which can be considered as complete, divides into two operational work modes, termed as inflow and outflow control. We show how controller combinations within a cell can integrate uptake and metabolization of a homeostatic controlled species and how pathways can be activated and lead to the formation of alternative products, as observed, for example, in the change of fermentation products by microorganisms when the supply of the carbon source is altered. The antagonistic character of hormonal control systems can be understood by a combination of inflow and outflow controllers.
Collapse
Affiliation(s)
- T Drengstig
- Department of Electrical Engineering and Computer Science, University of Stavanger, Stavanger, Norway
| | | | | | | | | | | |
Collapse
|
20
|
Li Y, Lin L, Li Z, Ye X, Xiong K, Aryal B, Xu Z, Paroo Z, Liu Q, He C, Jin P. Iron homeostasis regulates the activity of the microRNA pathway through poly(C)-binding protein 2. Cell Metab 2012; 15:895-904. [PMID: 22633452 PMCID: PMC3613991 DOI: 10.1016/j.cmet.2012.04.021] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 03/05/2012] [Accepted: 04/27/2012] [Indexed: 12/20/2022]
Abstract
MicroRNAs (miRNAs) control gene expression by promoting degradation or repressing translation of target mRNAs. The components of the miRNA pathway are subject to diverse modifications that can modulate the abundance and function of miRNAs. Iron is essential for fundamental metabolic processes, and its homeostasis is tightly regulated. Here we identified iron chelators as a class of activator of the miRNA pathway that could promote the processing of miRNA precursors. We show that cytosolic iron could regulate the activity of the miRNA pathway through poly(C)-binding protein 2 (PCBP2). PCBP2 is associated with Dicer and promotes the processing of miRNA precursors. Cytosolic iron could modulate the association between PCBP2 and Dicer, as well as the multimerization of PCBP2 and its ability to bind to miRNA precursors, which can alter the processing of miRNA precursors. Our findings reveal a role of iron homeostasis in the regulation of miRNA biogenesis.
Collapse
Affiliation(s)
- Yujing Li
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Chepelev NL, Willmore WG. Regulation of iron pathways in response to hypoxia. Free Radic Biol Med 2011; 50:645-66. [PMID: 21185934 DOI: 10.1016/j.freeradbiomed.2010.12.023] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2010] [Revised: 12/13/2010] [Accepted: 12/15/2010] [Indexed: 10/24/2022]
Abstract
Constituting an integral part of a heme's porphyrin ring, iron is essential for supplying cells and tissues with oxygen. Given tight links between oxygen delivery and iron availability, it is not surprising that iron deprivation and oxygen deprivation (hypoxia) have very similar consequences at the molecular level. Under hypoxia, the expression of major iron homeostasis genes including transferrin, transferrin receptor, ceruloplasmin, and heme oxygenase-1 is activated by hypoxia-inducible factors to provide increased iron availability for erythropoiesis in an attempt to enhance oxygen uptake and delivery to hypoxic cells. Iron-response proteins (IRP1 and IRP2) and "cap-n-collar" bZIP transcriptional factors (NE-F2 p45; Nrf1, 2, and 3; Bach1 and 2) also control gene and protein expression of the key iron homeostasis proteins. In this article, we give an overview of the mechanisms by which iron pathways are regulated by hypoxia at multiple levels. In addition, potential clinical benefits of manipulating iron pathways in the hypoxia-related conditions anemia and ischemia are discussed.
Collapse
|
22
|
Ye H, Rouault TA. Human iron-sulfur cluster assembly, cellular iron homeostasis, and disease. Biochemistry 2010; 49:4945-56. [PMID: 20481466 PMCID: PMC2885827 DOI: 10.1021/bi1004798] [Citation(s) in RCA: 192] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Revised: 05/18/2010] [Indexed: 01/19/2023]
Abstract
Iron-sulfur (Fe-S) proteins contain prosthetic groups consisting of two or more iron atoms bridged by sulfur ligands, which facilitate multiple functions, including redox activity, enzymatic function, and maintenance of structural integrity. More than 20 proteins are involved in the biosynthesis of iron-sulfur clusters in eukaryotes. Defective Fe-S cluster synthesis not only affects activities of many iron-sulfur enzymes, such as aconitase and succinate dehydrogenase, but also alters the regulation of cellular iron homeostasis, causing both mitochondrial iron overload and cytosolic iron deficiency. In this work, we review human Fe-S cluster biogenesis and human diseases that are caused by defective Fe-S cluster biogenesis. Fe-S cluster biogenesis takes place essentially in every tissue of humans, and products of human disease genes, including frataxin, GLRX5, ISCU, and ABCB7, have important roles in the process. However, the human diseases, Friedreich ataxia, glutaredoxin 5-deficient sideroblastic anemia, ISCU myopathy, and ABCB7 sideroblastic anemia/ataxia syndrome, affect specific tissues, while sparing others. Here we discuss the phenotypes caused by mutations in these different disease genes, and we compare the underlying pathophysiology and discuss the possible explanations for tissue-specific pathology in these diseases caused by defective Fe-S cluster biogenesis.
Collapse
Affiliation(s)
- Hong Ye
- Molecular Medicine Program, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | - Tracey A. Rouault
- Molecular Medicine Program, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| |
Collapse
|