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Yang R, Chen L, Zhang T, Yang S, Leng X, Zhao G. Self-assembly of ferritin nanocages into linear chains induced by poly(α, L-lysine). Chem Commun (Camb) 2014; 50:481-3. [PMID: 24263180 DOI: 10.1039/c3cc47847e] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The widespread occurrence of protein channels offers a good opportunity to fabricate protein architectures. Herein, we have developed a novel strategy for linear self-assembly of ferritin cages induced by poly(α, L-lysine) through channel-directed electrostatic interactions at pH 7.0. The length of the formed filaments can be controlled.
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Affiliation(s)
- R Yang
- CAU & ACC Joint-Laboratory of Space Food, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing Key Laboratory of Functional Food from Plant Resources, Beijing, 100083, China.
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DeLaat DM, Colombo CA, Chiorato AF, Carbonell SAM. Induction of ferritin synthesis by water deficit and iron excess in common bean (Phaseolus vulgaris L.). Mol Biol Rep 2014; 41:1427-35. [PMID: 24390245 DOI: 10.1007/s11033-013-2987-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 12/24/2013] [Indexed: 12/26/2022]
Abstract
Ferritins are molecules for iron storage present in most living beings. In plants, ferritin is an essential iron homeostasis regulator and therefore plays a fundamental role in control of iron induced by oxidative stress or by excess of iron ions. Ferritin gene expression is modulated by various environmental factors, including the intensity of drought, cold, light and pathogenic attack. Common bean, one of the most important species in the Brazilian diet, is also affected by insufficiency or lack of water. Thus, the present study was conducted for the purpose of determining the levels of expression of ferritins transcripts in leaf tissues of three common bean cultivars (BAT 477, Carioca Comum and IAC-Diplomata) under osmotic shock caused by polyethylene glycol 6000 and by iron excess. The expression of three ferritins genes (PvFer1, PvFer2 and PvFer3), determined by quantitative PCR, indicated a difference in the expression kinetics among the cultivars. All the ferritin genes were actively transcribed under iron excess and water deficit conditions. The cultivars most responsive to treatments were BAT 477 and IAC-Diplomata. All the cultivars responded to treatments. Nevertheless, the ferritin genes were differentially regulated according to the cultivars. Analysis of variance indicated differences among cultivars in expression of the genes PvFer1 and PvFer3. Both genes were most responsive to treatments. This result suggests that ferritin genes may be functionally important in acclimatization of common bean under iron excess or water deficit conditions.
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Lv C, Bai Y, Yang S, Zhao G, Chen B. NADH induces iron release from pea seed ferritin: a model for interaction between coenzyme and protein components in foodstuffs. Food Chem 2013; 141:3851-8. [PMID: 23993558 DOI: 10.1016/j.foodchem.2013.06.102] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 05/09/2013] [Accepted: 06/24/2013] [Indexed: 01/17/2023]
Abstract
Plant ferritin from legume seeds co-exists with coenzyme NADH (a reduced form of nicotinamide-adenine dinucleotide) in many foodstuffs. In the present study, the interaction of NADH with apo pea seed ferritin (PSF) was investigated by fluorescence resonance energy transfer (FRET), fluorescence titration, transmission electron microscope (TEM), and isothermal titration calorimetry (ITC). We found that NADH molecules bound on the outer surface of PSF close to the 4-fold channels, which was 1.58 nm from tryptophan residue (Trp). Consequently, such binding facilitates iron release from holo PSF, which might have a negative effect on PSF as an iron supplement, while NADH was oxidised into NAD(+). However, the binding of NADH to the protein does not affect the entry of toxic ferrous ions into the apo protein shell, where these ferrous ions were oxidised into less toxic ferric ions. Moreover, NADH binding markedly affects the tertiary structure around Trp residues of PSF. These findings advanced our understanding of the interactions between different naturally occurring components in a complex food system.
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Affiliation(s)
- Chenyan Lv
- CAU & ACC Joint-Laboratory of Space Food, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing Key Laboratory of Functional Food from Plant Resources, Beijing 100083, China
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Dissecting plant iron homeostasis under short and long-term iron fluctuations. Biotechnol Adv 2013; 31:1292-307. [PMID: 23680191 DOI: 10.1016/j.biotechadv.2013.05.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 04/18/2013] [Accepted: 05/05/2013] [Indexed: 12/30/2022]
Abstract
A wealth of information on the different aspects of iron homeostasis in plants has been obtained during the last decade. However, there is no clear road-map integrating the relationships between the various components. The principal aim of the current review is to fill this gap. In this context we discuss the lack of low affinity iron uptake mechanisms in plants, the utilization of a different uptake mechanism by graminaceous plants compared to the others, as well as the roles of riboflavin, ferritin isoforms, nitric oxide, nitrosylation, heme, aconitase, and vacuolar pH. Cross-homeostasis between elements is also considered, with a specific emphasis on the relationship between iron homeostasis and phosphorus and copper deficiencies. As the environment is a crucial parameter for modulating plant responses, we also highlight how diurnal fluctuations govern iron metabolism. Evolutionary aspects of iron homeostasis have so far attracted little attention. Looking into the past can inform us on how long-term oxygen and iron-availability fluctuations have influenced the evolution of iron uptake mechanisms. Finally, we evaluate to what extent this homeostastic road map can be used for the development of novel biofortification strategies in order to alleviate iron deficiency in human.
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Li M, Yun S, Yang X, Zhao G. Stability and iron oxidation properties of a novel homopolymeric plant ferritin from adzuki bean seeds: a comparative analysis with recombinant soybean seed H-1 chain ferritin. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1830:2946-53. [PMID: 23313843 DOI: 10.1016/j.bbagen.2013.01.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2012] [Revised: 01/03/2013] [Accepted: 01/04/2013] [Indexed: 10/27/2022]
Abstract
BACKGROUND All reported plant ferritins are heteropolymers comprising two different H-type subunits. Whether or not homopolymeric plant ferritin occurs in nature is an open question. METHODS A homopolymeric phytoferritin from adzuki bean seeds (ASF) was obtained by various protein purification techniques for the first time, which shares the highest identity (89.6%) with soybean seed H-1 ferritin (rH-1). Therefore, we compared iron oxidation activity and protein stability of ASF with those of rH-1 by stopped-flow combined with light scattering or UV/Vis spectrophotography, SDS- and native- PAGE analyses. Additionally, a new rH-1 variant (S68E) was prepared by site-directed mutagenesis approach to elucidate their difference in protein stability. RESULTS At high iron loading of protein, the extension peptide (EP) of plant ferritin was involved in iron oxidation, and the EP of ASF exhibited a much stronger iron oxidative activity than that of rH-1. Besides, ASF is more stable than rH-1 during storage, which is ascribed to one amino acid residue, Ser68. CONCLUSIONS ASF exhibits a different mechanism in iron oxidation from rH-1 at high iron loading of protein, and a higher stability than rH-1. These differences are mainly stemmed from their different EP sequences. GENERAL SIGNIFICANCE This work demonstrates that plant cells have evolved the EP of phytoferritin to control iron chemistry and protein stability by exerting a fine tuning of its amino acid sequence.
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Affiliation(s)
- Meiliang Li
- CAU & ACC Joint-Laboratory of Space Food, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing Key Laboratory of Functional Food from Plant Resources, Beijing 100083, China
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56
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Masuda H, Kobayashi T, Ishimaru Y, Takahashi M, Aung MS, Nakanishi H, Mori S, Nishizawa NK. Iron-biofortification in rice by the introduction of three barley genes participated in mugineic acid biosynthesis with soybean ferritin gene. FRONTIERS IN PLANT SCIENCE 2013; 4:132. [PMID: 23675379 PMCID: PMC3653162 DOI: 10.3389/fpls.2013.00132] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Accepted: 04/20/2013] [Indexed: 05/03/2023]
Abstract
Iron deficiency is a serious problem around the world, especially in developing countries. The production of iron-biofortified rice will help ameliorate this problem. Previously, expression of the iron storage protein, ferritin, in rice using an endosperm-specific promoter resulted in a two-fold increase in iron concentration in the resultant transgenic seeds. However, further over expression of ferritin did not produce an additional increase in the seed iron concentration, and symptoms of iron deficiency were noted in the leaves of the transgenic plants. In the present study, we aimed to further increase the iron concentration in rice seeds without increasing the sensitivity to iron deficiency by enhancing the uptake and transport of iron via a ferric iron chelator, mugineic acid. To this end, we introduced the soybean ferritin gene (SoyferH2) driven by two endosperm-specific promoters, along with the barley nicotianamine synthase gene (HvNAS1), two nicotianamine aminotransferase genes (HvNAAT-A and -B), and a mugineic acid synthase gene (IDS3) to enhance mugineic acid production in rice plants. A marker-free vector was utilized as a means of increasing public acceptance. Representative lines were selected from 102 transformants based on the iron concentration in polished seeds and ferritin accumulation in the seeds. These lines were grown in both commercially supplied soil (iron-sufficient conditions) and calcareous soil (iron-deficient conditions). Lines expressing both ferritin and mugineic acid biosynthetic genes showed signs of iron-deficiency tolerance in calcareous soil. The iron concentration in polished T3 seeds was increased by 4 and 2.5 times, as compared to that in non-transgenic lines grown in normal and calcareous soil, respectively. These results indicate that the concomitant introduction of the ferritin gene and mugineic acid biosynthetic genes effectively increased the seed iron level without causing iron sensitivity under iron-limited conditions.
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Affiliation(s)
- Hiroshi Masuda
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural UniversityIshikawa, Japan
- Graduate School of Agricultural and Life Sciences, The University of TokyoTokyo, Japan
| | - Takanori Kobayashi
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural UniversityIshikawa, Japan
- Graduate School of Agricultural and Life Sciences, The University of TokyoTokyo, Japan
| | - Yasuhiro Ishimaru
- Graduate School of Agricultural and Life Sciences, The University of TokyoTokyo, Japan
| | - Michiko Takahashi
- Graduate School of Agricultural and Life Sciences, The University of TokyoTokyo, Japan
| | - May S. Aung
- Graduate School of Agricultural and Life Sciences, The University of TokyoTokyo, Japan
| | - Hiromi Nakanishi
- Graduate School of Agricultural and Life Sciences, The University of TokyoTokyo, Japan
| | - Satoshi Mori
- Graduate School of Agricultural and Life Sciences, The University of TokyoTokyo, Japan
| | - Naoko K. Nishizawa
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural UniversityIshikawa, Japan
- Graduate School of Agricultural and Life Sciences, The University of TokyoTokyo, Japan
- *Correspondence: Naoko K. Nishizawa, Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, 1-308 Suematsu, Nonoichi, Ishikawa, 921-8836, Japan. e-mail:
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Yun S, Yang S, Huang L, Qi X, Mu P, Zhao G. Isolation and characterization of a new phytoferritin from broad bean (Vicia faba) seed with higher stability compared to pea seed ferritin. Food Res Int 2012. [DOI: 10.1016/j.foodres.2012.04.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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58
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Iron biofortification in rice by the introduction of multiple genes involved in iron nutrition. Sci Rep 2012; 2:543. [PMID: 22848789 PMCID: PMC3408131 DOI: 10.1038/srep00543] [Citation(s) in RCA: 153] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 06/29/2012] [Indexed: 11/08/2022] Open
Abstract
To address the problem of iron-deficiency anemia, one of the most prevalent human micronutrient deficiencies globally, iron-biofortified rice was produced using three transgenic approaches: by enhancing iron storage in grains via expression of the iron storage protein ferritin using endosperm-specific promoters, enhancing iron translocation through overproduction of the natural metal chelator nicotianamine, and enhancing iron flux into the endosperm by means of iron(II)-nicotianamine transporter OsYSL2 expression under the control of an endosperm-specific promoter and sucrose transporter promoter. Our results indicate that the iron concentration in greenhouse-grown T(2) polished seeds was sixfold higher and that in paddy field-grown T(3) polished seeds was 4.4-fold higher than that in non-transgenic seeds, with no defect in yield. Moreover, the transgenic seeds accumulated zinc up to 1.6-times in the field. Our results demonstrate that introduction of multiple iron homeostasis genes is more effective for iron biofortification than the single introduction of individual genes.
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59
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Liao X, Lv C, Zhang X, Masuda T, Li M, Zhao G. A novel strategy of natural plant ferritin to protect DNA from oxidative damage during iron oxidation. Free Radic Biol Med 2012; 53:375-82. [PMID: 22580341 DOI: 10.1016/j.freeradbiomed.2012.05.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 04/01/2012] [Accepted: 05/01/2012] [Indexed: 11/16/2022]
Abstract
Plant ferritin is a naturally occurring heteropolymer in plastids, where Fe(2+) is oxidatively deposited into the protein. However, the effect of this process on the coexistence of DNA and plant ferritin in the plastids is unknown. To investigate this effect, we built a system in which various plant ferritins and DNA coexist, followed by treatment with ferrous ions under aerobic conditions. Interestingly, naturally occurring soybean seed ferritin (SSF), a heteropolymer with an H-1/H-2 ratio of 1 to 1 in the apo form, completely protected DNA from oxidative damage during iron oxidative deposition into protein, and a similar result was obtained with its recombinant form, but not with its homopolymeric counterparts, apo rH-1 and apo rH-2. We demonstrate that the difference in DNA protection between heteropolymeric and homopolymeric plant ferritins stems from their different strategies to control iron chemistry during the above oxidative process. For example, the detoxification reaction occurs only in the presence of apo heteropolymeric SSF (hSSF), thereby preventing the production of hydroxyl radicals. In contrast, hydroxyl radicals are apparently generated via the Fenton reaction when apo rH-1 or rH-2 is used instead of apo hSSF. Thus, a combination of H-1 and H-2 subunits in hSSF seems to impart a unique DNA-protective function to the protein, which was previously unrecognized. This new finding advances our understanding of the structure and function of ferritin and of the widespread occurrence of heteropolymeric plant ferritin in nature.
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Affiliation(s)
- Xiayun Liao
- CAU & ACC Joint Laboratory of Space Food, College of Food Science and Nutritional Engineering, China Agricultural University, and Key Laboratory of Functional Dairy, Ministry of Education, Beijing 100083, China
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60
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Li M, Jia X, Yang J, Deng J, Zhao G. Effect of tannic acid on properties of soybean (Glycine max) seed ferritin: a model for interaction between naturally-occurring components in foodstuffs. Food Chem 2012; 133:410-5. [PMID: 25683413 DOI: 10.1016/j.foodchem.2012.01.052] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Revised: 12/30/2011] [Accepted: 01/17/2012] [Indexed: 12/25/2022]
Abstract
There are many components with different properties co-existing in food, so interactions among these components are likely to occur, thereby affecting food quality. However, relatively little information is available on such interactions. In this study, we focus on the interaction between tannic acid (TA) and soybean seed ferritin (SSF), since they co-exist in many foodstuffs, and the consequence of this interaction. As expected, TA interacts with SSF, resulting in changes in the tertiary/quaternary structure of the protein, while having no effect on its primary and secondary structure. On one hand, such interaction leads to protein association, which markedly inhibited ferritin degradation by pepsin at pH 4.0 and trypsin at pH 7.5. On the other hand, iron release was faster with TA than with ascorbic acid, and such release has a negative effect on iron supplementation. These results help to understand the interactions of food components.
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Affiliation(s)
- Meiliang Li
- CAU & ACC Joint-Laboratory of Space Food, College of Food Science and Nutritional Engineering, China Agricultural University, Key Laboratory of Functional Dairy, Ministry of Education, Beijing 100083, China
| | - Xiaoling Jia
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Jingyun Yang
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Jianjun Deng
- CAU & ACC Joint-Laboratory of Space Food, College of Food Science and Nutritional Engineering, China Agricultural University, Key Laboratory of Functional Dairy, Ministry of Education, Beijing 100083, China
| | - Guanghua Zhao
- CAU & ACC Joint-Laboratory of Space Food, College of Food Science and Nutritional Engineering, China Agricultural University, Key Laboratory of Functional Dairy, Ministry of Education, Beijing 100083, China.
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61
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Masuda T, Morimoto SI, Mikami B, Toyohara H. The extension peptide of plant ferritin from sea lettuce contributes to shell stability and surface hydrophobicity. Protein Sci 2012; 21:786-96. [PMID: 22419613 DOI: 10.1002/pro.2061] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Accepted: 03/09/2012] [Indexed: 01/22/2023]
Abstract
Plant ferritins have some unique structural and functional features. Most of these features can be related to the plant-specific "extension peptide" (EP), which exists in the N-terminus of the mature region of a plant ferritin. Recent crystallographic analysis of a plant ferritin revealed the structure of the EP, however, two points remain unclear: (i) whether the structures of well-conserved EP of plant ferritins are common in all plants, and (ii) whether the EP truly contributes to the shell stability of the plant ferritin oligomer. To clarify these matters, we have cloned a green-plant-type ferritin cDNA from a green alga, Ulva pertusa, and investigated its crystal structure. Ulva pertusa ferritin (UpFER) has a plant-ferritin-specific extension peptide composed of 28 amino acid residues. In the crystal structure of UpFER, the EP lay on and interacted with the neighboring threefold symmetry-related subunit. The amino acid residues involved in the interaction were very highly conserved among plant ferritins. The EPs masked the hydrophobic pockets on the ferritin shell surface by lying on them, and this made the ferritin oligomer more hydrophilic. Furthermore, differential scanning calorimetric analysis of the native and its EP-deletion mutant suggested that the EP contributed to the thermal stability of the plant ferritin shell. Thus, the shell stability and surface hydrophobicity of plant ferritin were controlled by the presence or absence of the plant-ferritin-specific EP. This regulation can account for those processes such as shell stability, degradation, and association of plant ferritin, which are significantly related to iron utilization in plants.
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Affiliation(s)
- Taro Masuda
- Laboratory of Food Quality Design and Development, Division of Agronomy and Horticultural Science, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan.
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Galatro A, Robello E, Puntarulo S. Soybean ferritin: isolation, characterization, and free radical generation. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2012; 54:45-54. [PMID: 22112169 DOI: 10.1111/j.1744-7909.2011.01091.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The main aim of this work was to assess the multi-task role of ferritin (Ft) in the oxidative metabolism of soybean (Glycine max). Soybean seeds incubated for 24 h yielded 41 ± 5 μg Ft/g fresh weight. The rate of in vitro incorporation of iron (Fe) into Ft was tested by supplementing the reaction medium with physiological Fe chelators. The control rate, observed in the presence of 100 μM Fe, was not significantly different from the values observed in the presence of 100 μM Fe-his. However, it was significantly higher in the presence of 100 μM Fe-citrate (approximately 4.5-fold) or of 100 μM Fe-ATP (approximately 14-fold). Moreover, a substantial decrease in the Trp-dependent fluorescence of the Ft protein was determined during Fe uptake from Fe-citrate, as compared with the control. On the other hand, Ft addition to homogenates from soybean embryonic axes reduced endogenously generated ascorbyl radical, according to its capacity for Fe uptake. The data presented here suggest that Ft could be involved in the generation of free radicals, such as hydroxyl radical, by Fe-catalyzed reactions. Moreover, the scavenging of these radicals by Ft itself could then lead to protein damage. However, Ft could also prevent cellular damage by the uptake of catalytically active Fe.
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Affiliation(s)
- Andrea Galatro
- Physical Chemistry-PRALIB, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires C1113AAD, Argentina
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64
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Zhu B, Ke CH, Huang HQ. Mass spectrometric characteristics and kinetics of iron release in visceral mass of Saccostrea cucullata. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2011; 25:2418-2424. [PMID: 21818800 DOI: 10.1002/rcm.5138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Ferritins with electrophoretic homogeneity were prepared from the visceral mass of Saccostrea cucullata in batch. The native PAGE approach showed similar electrophoretic mobility among pig pancreatic ferritin, liver ferritin of Dasyatis akajei, and visceral mass ferritin of Saccostrea cucullata. SDS-PAGE indicated that the Saccostrea cucullata visceral ferritin (SCVF) consisted of a single subunit type and had a molecular weight (MW) of approximately 20 kDa, suggesting that the protein shell in SCVF was composed of a single subunit. In addition, peptide mass fingerprinting and transmission electron microscopy were used to identify SCVF further, and to observe its molecular structure. We found that the molecular structure in SCVF was similar to that of most mammalian ferritins, which are composed of a protein shell and an iron core. The results of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry under the assistance of an acidic matrix, sinapic acid, also showed that SCVF was composed of a single subunit type and its subunit MW was calculated to be 19871.042 Da in the absence of heme. Kinetics analysis revealed that the complete process of iron release fitted the law of a first-order reaction, which is similar to that of most ferritins in mammals. Similar to bacterial ferritin, studies indicated that the shell consisted of a single subunit type and showed similar kinetics of iron release, suggesting that this subunit plays two important roles in iron release and storage, and that it shows different stability and intensity of interaction in carrying out its physiological functions in SCVF.
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Affiliation(s)
- Bo Zhu
- State Key Laboratory of Stress Cell Biology (Xiamen University), School of Life Sciences, Xiamen University, Xiamen, China
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65
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Xu XY, Fan R, Zheng R, Li CM, Yu DY. Proteomic analysis of seed germination under salt stress in soybeans. J Zhejiang Univ Sci B 2011; 12:507-17. [PMID: 21726057 PMCID: PMC3134839 DOI: 10.1631/jzus.b1100061] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Accepted: 05/26/2011] [Indexed: 11/11/2022]
Abstract
Soybean (Glycine max (L.) Merrill) is a salt-sensitive crop, and its production is severely affected by saline soils. Therefore, the response of soybean seeds to salt stress during germination was investigated at both physiological and proteomic levels. The salt-tolerant cultivar Lee68 and salt-sensitive cultivar N2899 were exposed to 100 mmol/L NaCl until radicle protrusion from the seed coat. In both cultivars, the final germination percentage was not affected by salt, but the mean germination times of Lee68 and N2899 were delayed by 0.3 and 1.0 d, respectively, compared with controls. In response to salt stress, the abscisic acid content increased, and gibberellic acid (GA₁+₃) and isopentenyladenosine decreased. Indole-3-acetic acid increased in Lee68, but remained unchanged in N2899. The proteins extracted from germinated seeds were separated using two-dimensional gel electrophoresis (2-DE), followed by Coomassie brilliant blue G-250 staining. About 350 protein spots from 2-DE gels of pH range 3 to 10 and 650 spots from gels of pH range 4 to 7 were reproducibly resolved, of which 18 protein spots showed changes in abundance as a result of salt stress in both cultivars. After matrix-assisted laser desorption ionization-time of flight-mass spectroscopy (MALDI-TOF-MS) analysis of the differentially expressed proteins, the peptide mass fingerprint was searched against the soybean UniGene database and nine proteins were successfully identified. Ferritin and 20S proteasome subunit β-6 were up-regulated in both cultivars. Glyceraldehyde 3-phosphate dehydrogenase, glutathione S-transferase (GST) 9, GST 10, and seed maturation protein PM36 were down-regulated in Lee68 by salt, but still remained at a certain level. However, these proteins were present in lower levels in control N2899 and were up-regulated under salt stress. The results indicate that these proteins might have important roles in defense mechanisms against salt stress during soybean seed germination.
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Affiliation(s)
- Xiao-yan Xu
- National Center for Soybean Improvement, National Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
- Foundation Department, Jiangsu Polytechnic College of Agriculture and Forestry, Jurong 212400, China
| | - Rui Fan
- National Center for Soybean Improvement, National Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - Rui Zheng
- National Center for Soybean Improvement, National Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
- College of Life Sciences, Ningxia University, Yinchuan 750021, China
| | - Chun-mei Li
- National Center for Soybean Improvement, National Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
| | - De-yue Yu
- National Center for Soybean Improvement, National Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
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Deng J, Li M, Zhang T, Chen B, Leng X, Zhao G. Binding of proanthocyanidins to soybean (Glycine max) seed ferritin inhibiting protein degradation by protease in vitro. Food Res Int 2011. [DOI: 10.1016/j.foodres.2010.11.020] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Yang H, Fu X, Li M, Leng X, Chen B, Zhao G. Protein association and dissociation regulated by extension peptide: a mode for iron control by phytoferritin in seeds. PLANT PHYSIOLOGY 2010; 154:1481-91. [PMID: 20841455 PMCID: PMC2971622 DOI: 10.1104/pp.110.163063] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Accepted: 09/13/2010] [Indexed: 05/10/2023]
Abstract
Most of the iron in legume seeds is stored in ferritin located in the amyloplast, which is used during seed germination. However, there is a lack of information on the regulation of iron by phytoferritin. In this study, soluble and insoluble forms of pea (Pisum sativum) seed ferritin (PSF) isolated from dried seeds were found to be identical 24-mer ferritins comprising H-1 and H-2 subunits. The insoluble form is favored at low pH, whereas the two forms reversibly interconvert in the pH range of 6.0 to 7.8, with an apparent pK(a) of 6.7. This phenomenon was not observed in animal ferritins, indicating that PSF is unique. The pH of the amyloplast was found to be approximately 6.0, thus facilitating PSF association, which is consistent with the role of PSF in long-term iron storage. Similar to previous studies, the results of this work showed that protein degradation occurs in purified PSF during storage, thus proving that phytoferritin also undergoes degradation during seedling germination. In contrast, no degradation was observed in animal ferritins, suggesting that this degradation of phytoferritin may be due to the extension peptide (EP), a specific domain found only in phytoferritin. Indeed, removal of EP from PSF significantly increased protein stability and prevented degradation under identical conditions while promoting protein dissociation. Correlated with such dissociation was a considerable increase in the rate of ascorbate-induced iron release from PSF at pH 6.0. Thus, phytoferritin may have facilitated the evolution of EP to enable it to regulate iron for storage or complement in seeds.
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Affiliation(s)
| | | | | | | | | | - Guanghua Zhao
- CAU and ACC Joint Laboratory of Space Food, College of Food Science and Nutritional Engineering, China Agricultural University, Key Laboratory of Functional Dairy, Ministry of Education, Beijing 100083, China (H.Y., X.F., M.L., X.L., G.Z.); State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing 100094, China (B.C.)
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68
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Deng J, Liao X, Yang H, Zhang X, Hua Z, Masuda T, Goto F, Yoshihara T, Zhao G. Role of H-1 and H-2 subunits of soybean seed ferritin in oxidative deposition of iron in protein. J Biol Chem 2010; 285:32075-86. [PMID: 20702403 PMCID: PMC2952209 DOI: 10.1074/jbc.m110.130435] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2010] [Revised: 08/11/2010] [Indexed: 11/06/2022] Open
Abstract
Naturally occurring phytoferritin is a heteropolymer consisting of two different H-type subunits, H-1 and H-2. Prior to this study, however, the function of the two subunits in oxidative deposition of iron in ferritin was unknown. The data show that, upon aerobic addition of 48-200 Fe(2+)/shell to apoferritin, iron oxidation occurs only at the diiron ferroxidase center of recombinant H1 (rH-1). In addition to the diiron ferroxidase mechanism, such oxidation is catalyzed by the extension peptide (a specific domain found in phytoferritin) of rH-2, because the H-1 subunit is able to remove Fe(3+) from the center to the inner cavity better than the H-2 subunit. These findings support the idea that the H-1 and H-2 subunits play different roles in iron mineralization in protein. Interestingly, at medium iron loading (200 irons/shell), wild-type (WT) soybean seed ferritin (SSF) exhibits a stronger activity in catalyzing iron oxidation (1.10 ± 0.13 μm iron/subunit/s) than rH-1 (0.59 ± 0.07 μm iron/subunit/s) and rH-2 (0.48 ± 0.04 μm iron/subunit/s), demonstrating that a synergistic interaction exists between the H-1 and H-2 subunits in SSF during iron mineralization. Such synergistic interaction becomes considerably stronger at high iron loading (400 irons/shell) as indicated by the observation that the iron oxidation activity of WT SSF is ∼10 times larger than those of rH-1 and rH-2. This helps elucidate the widespread occurrence of heteropolymeric ferritins in plants.
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Affiliation(s)
- Jianjun Deng
- From the CAU and ACC Joint Laboratory of Space Food, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Xiayun Liao
- From the CAU and ACC Joint Laboratory of Space Food, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Haixia Yang
- From the CAU and ACC Joint Laboratory of Space Food, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Xiangyu Zhang
- the State Key Laboratory of Pharmaceutical Biotechnology and Department of Biochemistry, College of Life Sciences, Nanjing University, Nanjing 210093, China, and
| | - Zichun Hua
- the State Key Laboratory of Pharmaceutical Biotechnology and Department of Biochemistry, College of Life Sciences, Nanjing University, Nanjing 210093, China, and
| | - Taro Masuda
- the Laboratory of Food Quality Design and Development, Division of Agronomy and Horticultural Science, Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Fumiyuki Goto
- the Biotechnology Sector, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, 1646 Abiko, Abiko, Chiba 270-1194, Japan
| | - Toshihiro Yoshihara
- the Biotechnology Sector, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, 1646 Abiko, Abiko, Chiba 270-1194, Japan
| | - Guanghua Zhao
- From the CAU and ACC Joint Laboratory of Space Food, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
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69
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Zhao G. Phytoferritin and its implications for human health and nutrition. Biochim Biophys Acta Gen Subj 2010; 1800:815-23. [DOI: 10.1016/j.bbagen.2010.01.009] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2009] [Revised: 01/15/2010] [Accepted: 01/18/2010] [Indexed: 01/02/2023]
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Briat JF, Ravet K, Arnaud N, Duc C, Boucherez J, Touraine B, Cellier F, Gaymard F. New insights into ferritin synthesis and function highlight a link between iron homeostasis and oxidative stress in plants. ANNALS OF BOTANY 2010; 105:811-22. [PMID: 19482877 PMCID: PMC2859905 DOI: 10.1093/aob/mcp128] [Citation(s) in RCA: 175] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2009] [Revised: 03/30/2009] [Accepted: 04/06/2009] [Indexed: 05/18/2023]
Abstract
BACKGROUND Iron is an essential element for both plant productivity and nutritional quality. Improving plant iron content was attempted through genetic engineering of plants overexpressing ferritins. However, both the roles of these proteins in plant physiology, and the mechanisms involved in the regulation of their expression are largely unknown. Although the structure of ferritins is highly conserved between plants and animals, their cellular localization differs. Furthermore, regulation of ferritin gene expression in response to iron excess occurs at the transcriptional level in plants, in contrast to animals which regulate ferritin expression at the translational level. SCOPE In this review, an overview of our knowledge of bacterial and mammalian ferritin synthesis and functions is presented. Then the following will be reviewed: (a) the specific features of plant ferritins; (b) the regulation of their synthesis during development and in response to various environmental cues; and (c) their function in plant physiology, with special emphasis on the role that both bacterial and plant ferritins play during plant-bacteria interactions. Arabidopsis ferritins are encoded by a small nuclear gene family of four members which are differentially expressed. Recent results obtained by using this model plant enabled progress to be made in our understanding of the regulation of the synthesis and the in planta function of these various ferritins. CONCLUSIONS Studies on plant ferritin functions and regulation of their synthesis revealed strong links between these proteins and protection against oxidative stress. In contrast, their putative iron-storage function to furnish iron during various development processes is unlikely to be essential. Ferritins, by buffering iron, exert a fine tuning of the quantity of metal required for metabolic purposes, and help plants to cope with adverse situations, the deleterious effects of which would be amplified if no system had evolved to take care of free reactive iron.
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71
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Fu X, Deng J, Yang H, Masuda T, Goto F, Yoshihara T, Zhao G. A novel EP-involved pathway for iron release from soya bean seed ferritin. Biochem J 2010; 427:313-21. [PMID: 20146668 DOI: 10.1042/bj20100015] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Iron in phytoferritin from legume seeds is required for seedling germination and early growth. However, the mechanism by which phytoferritin regulates its iron complement to these physiological processes remains unknown. In the present study, protein degradation is found to occur in purified SSF (soya bean seed ferritin) (consisting of H-1 and H-2 subunits) during storage, consistent with previous results that such degradation also occurs during seedling germination. In contrast, no degradation is observed with animal ferritin under identical conditions, suggesting that SSF autodegradation might be due to the EP (extension peptide) on the exterior surface of the protein, a specific domain found only in phytoferritin. Indeed, EP-deleted SSF becomes stable, confirming the above hypothesis. Further support comes from a protease activity assay showing that EP-1 (corresponding to the EP of the H-1 subunit) exhibits significant serine protease-like activity, whereas the activity of EP-2 (corresponding to the EP of the H-2 subunit) is much weaker. Consistent with the observation above, rH-1 (recombinant H-1 ferritin) is prone to degradation, whereas its analogue, rH-2, becomes very stable under identical conditions. This demonstrates that SSF degradation mainly originates from the serine protease-like activity of EP-1. Associated with EP degradation is a considerable increase in the rate of iron release from SSF induced by ascorbate in the amyloplast (pH range, 5.8-6.1). Thus phytoferritin may have facilitated the evolution of the specific domain to control its iron complement in response to cell iron need in the seedling stage.
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Affiliation(s)
- Xiaoping Fu
- China Agricultural University, Beijing, China
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72
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Eswaran N, Parameswaran S, Sathram B, Anantharaman B, Kumar G RK, Tangirala SJ. Yeast functional screen to identify genetic determinants capable of conferring abiotic stress tolerance in Jatropha curcas. BMC Biotechnol 2010; 10:23. [PMID: 20302659 PMCID: PMC2851662 DOI: 10.1186/1472-6750-10-23] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Accepted: 03/20/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Environmentally inflicted stresses such as salinity and drought limit the plant productivity both in natural and agricultural system. Increasing emphasis has been directed to molecular breeding strategies to enhance the intrinsic ability of plant to survive stress conditions. Functional screens in microorganisms with heterologous genes are a rapid, effective and powerful tool to identify stress tolerant genes in plants. Jatropha curcas (Physic nut) has been identified as a potential source of biodiesel plant. In order to improve its productivity under stress conditions to benefit commercial plantations, we initiated prospecting of novel genes expressed during stress in J. curcas that can be utilized to enhance stress tolerance ability of plant. RESULTS To identify genes expressed during salt tolerance, cDNA expression libraries were constructed from salt-stressed roots of J. curcas, regulated under the control of the yeast GAL1 system. Using a replica based screening, twenty thousand yeast transformants were screened to identify transformants expressing heterologous gene sequences from J. curcas with enhanced ability to tolerate stress. From the screen we obtained 32 full length genes from J. curcas [GenBank accession numbers FJ489601-FJ489611, FJ619041-FJ619057 and FJ623457-FJ623460] that can confer abiotic stress tolerance. As a part of this screen, we optimized conditions for salt stress in J. curcas, defined parameters for salt stress in yeast, as well as isolated three salt hypersensitive yeast strains shs-2, shs-6 and shs-8 generated through a process of random mutagenesis, and exhibited growth retardation beyond 750 mM NaCl. Further, we demonstrated complementation of the salt sensitive phenotypes in the shs mutants, and analyzed the expression patterns for selected J. curcas genes obtained from the screen in both leaf and root tissues after salt stress treatments. CONCLUSIONS The approach described in this report provides a rapid and universal assay system for large scale screening of genes for varied abiotic stress tolerance within a short span of time. Using this screening strategy we could isolate both genes with previously known function in stress tolerance as well as novel sequences with yet unknown function in salt stress tolerance from J. curcas. The isolated genes could be over-expressed using plant expression system to generate and evaluate transgenic plants for stress tolerance as well as be used as markers for breeding salt stress tolerance in plants.
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Affiliation(s)
- Nalini Eswaran
- Plant Metabolic Engineering Group, Reliance Life Sciences Pvt Ltd, Dhirubhai Ambani Life Sciences Center, R-282, Thane- Belapur Road, Rabale, Navi Mumbai- 400 701, India
| | - Sriram Parameswaran
- Plant Metabolic Engineering Group, Reliance Life Sciences Pvt Ltd, Dhirubhai Ambani Life Sciences Center, R-282, Thane- Belapur Road, Rabale, Navi Mumbai- 400 701, India
- DuPont Knowledge Centre, ICICI Knowledge Park, Genome Valley, Turkapalli, Shamirpet, Hyderabad 500 078, India
| | - Balaji Sathram
- Plant Metabolic Engineering Group, Reliance Life Sciences Pvt Ltd, Dhirubhai Ambani Life Sciences Center, R-282, Thane- Belapur Road, Rabale, Navi Mumbai- 400 701, India
| | - Bhagyam Anantharaman
- Plant Metabolic Engineering Group, Reliance Life Sciences Pvt Ltd, Dhirubhai Ambani Life Sciences Center, R-282, Thane- Belapur Road, Rabale, Navi Mumbai- 400 701, India
| | - Raja Krishna Kumar G
- Plant Metabolic Engineering Group, Reliance Life Sciences Pvt Ltd, Dhirubhai Ambani Life Sciences Center, R-282, Thane- Belapur Road, Rabale, Navi Mumbai- 400 701, India
| | - Sudhakar Johnson Tangirala
- Plant Metabolic Engineering Group, Reliance Life Sciences Pvt Ltd, Dhirubhai Ambani Life Sciences Center, R-282, Thane- Belapur Road, Rabale, Navi Mumbai- 400 701, India
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73
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Cvitanich C, Przybyłowicz WJ, Urbanski DF, Jurkiewicz AM, Mesjasz-Przybyłowicz J, Blair MW, Astudillo C, Jensen EØ, Stougaard J. Iron and ferritin accumulate in separate cellular locations in Phaseolus seeds. BMC PLANT BIOLOGY 2010; 10:26. [PMID: 20149228 PMCID: PMC2831038 DOI: 10.1186/1471-2229-10-26] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Accepted: 02/11/2010] [Indexed: 05/04/2023]
Abstract
BACKGROUND Iron is an important micronutrient for all living organisms. Almost 25% of the world population is affected by iron deficiency, a leading cause of anemia. In plants, iron deficiency leads to chlorosis and reduced yield. Both animals and plants may suffer from iron deficiency when their diet or environment lacks bioavailable iron. A sustainable way to reduce iron malnutrition in humans is to develop staple crops with increased content of bioavailable iron. Knowledge of where and how iron accumulates in seeds of crop plants will increase the understanding of plant iron metabolism and will assist in the production of staples with increased bioavailable iron. RESULTS Here we reveal the distribution of iron in seeds of three Phaseolus species including thirteen genotypes of P. vulgaris, P. coccineus, and P. lunatus. We showed that high concentrations of iron accumulate in cells surrounding the provascular tissue of P. vulgaris and P. coccineus seeds. Using the Perls' Prussian blue method, we were able to detect iron in the cytoplasm of epidermal cells, cells near the epidermis, and cells surrounding the provascular tissue. In contrast, the protein ferritin that has been suggested as the major iron storage protein in legumes was only detected in the amyloplasts of the seed embryo. Using the non-destructive micro-PIXE (Particle Induced X-ray Emission) technique we show that the tissue in the proximity of the provascular bundles holds up to 500 microg g(-1) of iron, depending on the genotype. In contrast to P. vulgaris and P. coccineus, we did not observe iron accumulation in the cells surrounding the provascular tissues of P. lunatus cotyledons. A novel iron-rich genotype, NUA35, with a high concentration of iron both in the seed coat and cotyledons was bred from a cross between an Andean and a Mesoamerican genotype. CONCLUSIONS The presented results emphasize the importance of complementing research in model organisms with analysis in crop plants and they suggest that iron distribution criteria should be integrated into selection strategies for bean biofortification.
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Affiliation(s)
- Cristina Cvitanich
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology, University of Aarhus, Aarhus, Denmark
| | - Wojciech J Przybyłowicz
- Materials Research Department, iThemba LABS, Somerset West, South Africa
- on leave from: Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Kraków, Poland
| | - Dorian F Urbanski
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology, University of Aarhus, Aarhus, Denmark
| | - Anna M Jurkiewicz
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology, University of Aarhus, Aarhus, Denmark
| | | | - Matthew W Blair
- International Center for Tropical Agriculture, Cali, Colombia
| | | | - Erik Ø Jensen
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology, University of Aarhus, Aarhus, Denmark
| | - Jens Stougaard
- Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology, University of Aarhus, Aarhus, Denmark
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Masuda T, Goto F, Yoshihara T, Mikami B. Crystal structure of plant ferritin reveals a novel metal binding site that functions as a transit site for metal transfer in ferritin. J Biol Chem 2010; 285:4049-4059. [PMID: 20007325 PMCID: PMC2823546 DOI: 10.1074/jbc.m109.059790] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Revised: 11/25/2009] [Indexed: 11/06/2022] Open
Abstract
Ferritins are important iron storage and detoxification proteins that are widely distributed in living kingdoms. Because plant ferritin possesses both a ferroxidase site and a ferrihydrite nucleation site, it is a suitable model for studying the mechanism of iron storage in ferritin. This article presents for the first time the crystal structure of a plant ferritin from soybean at 1.8-A resolution. The soybean ferritin 4 (SFER4) had a high structural similarity to vertebrate ferritin, except for the N-terminal extension region, the C-terminal short helix E, and the end of the BC-loop. Similar to the crystal structures of other ferritins, metal binding sites were observed in the iron entry channel, ferroxidase center, and nucleation site of SFER4. In addition to these conventional sites, a novel metal binding site was discovered intermediate between the iron entry channel and the ferroxidase site. This site was coordinated by the acidic side chain of Glu(173) and carbonyl oxygen of Thr(168), which correspond, respectively, to Glu(140) and Thr(135) of human H chain ferritin according to their sequences. A comparison of the ferroxidase activities of the native and the E173A mutant of SFER4 clearly showed a delay in the iron oxidation rate of the mutant. This indicated that the glutamate residue functions as a transit site of iron from the 3-fold entry channel to the ferroxidase site, which may be universal among ferritins.
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Affiliation(s)
- Taro Masuda
- From the Laboratory of Food Quality Design and Development, Division of Agronomy and Horticultural Science, Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto 611-0011.
| | - Fumiyuki Goto
- the Biotechnology Sector, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, 1646 Abiko, Abiko, Chiba 270-1194, Japan
| | - Toshihiro Yoshihara
- the Biotechnology Sector, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, 1646 Abiko, Abiko, Chiba 270-1194, Japan
| | - Bunzo Mikami
- the Laboratory of Applied Structural Biology, Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto 611-0011 and
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75
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Deng J, Cheng J, Liao X, Zhang T, Leng X, Zhao G. Comparative study on iron release from soybean (Glycine max) seed ferritin induced by anthocyanins and ascorbate. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:635-41. [PMID: 19921836 DOI: 10.1021/jf903046u] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Anthocyanins have received much attentions due to their various activities. Phytoferritin represents a novel alternative for iron supplementation. In the present study, it was found that all tested anthocyanins such as cyanidin (Cy), delphinidin (Dp), delphinidin-3-O-glucoside (Dp3glc), malvidin (Mv), petunidin (Pt), and petunidin-3-O-glucoside (Pt3glc) had a strong interaction with SSF, respectively, resulting in iron release from soybean seed ferritin (SSF) just as for ascorbate. The order of iron release from SSF is as follows: Dp>Cy>Pt>Mv>Dp3glc>Pt3glc. Their ability to liberate iron from SSF is associated with the size of the molecules and the chemical structures but mainly depends on their chelating activity with Fe2+. Interestingly, these pigments inhibited SSF degradation during the iron release to different extents while ascorbate did not. The difference in protective effects on SFF between ascorbate and the anthocyanins is in good agreement with their different Fe2+-chelating activities.
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Affiliation(s)
- Jianjun Deng
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, People's Republic of China
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76
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Deng J, Liao X, Hu J, Leng X, Cheng J, Zhao G. Purification and characterization of new phytoferritin from black bean (Phaseolus vulgaris L.) seed. ACTA ACUST UNITED AC 2010; 147:679-88. [DOI: 10.1093/jb/mvp212] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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77
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Briat JF, Duc C, Ravet K, Gaymard F. Ferritins and iron storage in plants. Biochim Biophys Acta Gen Subj 2009; 1800:806-14. [PMID: 20026187 DOI: 10.1016/j.bbagen.2009.12.003] [Citation(s) in RCA: 173] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Revised: 12/07/2009] [Accepted: 12/08/2009] [Indexed: 10/20/2022]
Abstract
Iron is essential for both plant productivity and nutritional quality. Improving plant iron content was attempted through genetic engineering of plants overexpressing ferritins. However, both the roles of these proteins in the plant physiology, and the mechanisms involved in the regulation of their expression are largely unknown. Although the structure of ferritins is highly conserved between plants and animals, their cellular localization differ. Furthermore, regulation of ferritin gene expression in response to iron excess occurs at the transcriptional level in plants, in contrast to animals which regulate ferritin expression at the translational level. In this review, our knowledge of the specific features of plant ferritins is presented, at the level of their (i) structure/function relationships, (ii) cellular localization, and (iii) synthesis regulation during development and in response to various environmental cues. A special emphasis is given to their function in plant physiology, in particular concerning their respective roles in iron storage and in protection against oxidative stress. Indeed, the use of reverse genetics in Arabidopsis recently enabled to produce various knock-out ferritin mutants, revealing strong links between these proteins and protection against oxidative stress. In contrast, their putative iron storage function to furnish iron during various development processes is unlikely to be essential. Ferritins, by buffering iron, exert a fine tuning of the quantity of metal required for metabolic purposes, and help plants to cope with adverse situations, the deleterious effects of which would be amplified if no system had evolved to take care of free reactive iron.
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Affiliation(s)
- Jean-François Briat
- Biochimie et Physiologie Moleculaire des Plantes, Centre National de la Recherche Scientifique, Institut National de la Recherche Agronomique, Université Montpellier 2, SupAgro. Bat 7, 2 place Viala, 34060 Montpellier cedex 1, France.
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78
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Li C, Qi X, Li M, Zhao G, Hu X. Phosphate facilitates Fe(II) oxidative deposition in pea seed (Pisum sativum) ferritin. Biochimie 2009; 91:1475-81. [PMID: 19735693 DOI: 10.1016/j.biochi.2009.08.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2009] [Accepted: 08/27/2009] [Indexed: 11/17/2022]
Abstract
The iron core within phytoferritin interior usually contains the high ratio of iron to phosphate, agreeing with the fact that phosphorus and iron are essential nutrient elements for plant growth. It was established that iron oxidation and incorporation into phytoferritin shell occurs in the plastid(s) where the high concentration of phosphate occurs. However, so far, the role of phosphate in iron oxidative deposition in plant ferritin has not been recognized yet. In the present study, Fe(II) oxidative deposition in pea seed ferritin (PSF) was aerobically investigated in the presence of phosphate. Results indicated that phosphate did not affect the stoichiometry of the initial iron(II) oxidation reaction that takes place at ferroxidase centers upon addition of < or =48 Fe(II)/protein to apoferritin, but increased the rate of iron oxidation. At high Fe(II) fluxes into ferritin (>48 Fe(II)/protein), phosphate plays a more significant role in Fe(II) oxidative deposition. For instance, phosphate increased the rate of Fe(II) oxidation about 1-3 fold, and such an increase depends on the concentration of phosphate in the range of 0-2 mM. This effect was attributed to the ability of phosphate to improve the regeneration activity of ferroxidase centers in PSF. In addition, the presence of phosphate caused a significant decrease in the absorption properties of iron core, indicating that phosphate is involved in the formation of the iron core.
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Affiliation(s)
- Chaorui Li
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
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79
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Ravet K, Touraine B, Kim SA, Cellier F, Thomine S, Guerinot ML, Briat JF, Gaymard F. Post-translational regulation of AtFER2 ferritin in response to intracellular iron trafficking during fruit development in Arabidopsis. MOLECULAR PLANT 2009; 2:1095-106. [PMID: 19825683 DOI: 10.1093/mp/ssp041] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Ferritins are major players in plant iron homeostasis. Surprisingly, their overexpression in transgenic plants led only to a moderate increase in seed iron content, suggesting the existence of control checkpoints for iron loading and storage in seeds. This work reports the identification of two of these checkpoints. First, measurement of seed metal content during fruit development in Arabidopsis thaliana reveals a similar dynamic of loading for Fe, Mn, Cu, and Zn. The step controlling metal loading into the seed occurs by the regulation of transport from the hull to the seed. Second, metal loading and ferritin abundance were monitored in different genetic backgrounds affected in vacuolar iron transport (AtVIT1, AtNRAMP3, AtNRAMP4) or plastid iron storage (AtFER1 to 4). This approach revealed (1) a post-translational regulation of ferritin accumulation in seeds, and (2) that ferritin stability depends on the balance of iron allocation between vacuoles and plastids. Thus, the success of ferritin overexpression strategies for iron biofortification, a promising approach to reduce iron-deficiency anemia in developing countries, would strongly benefit from the identification and engineering of mechanisms enabling the translocation of high amounts of iron into seed plastids.
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Affiliation(s)
- Karl Ravet
- Biochimie et Physiologie Moléculaire des Plantes (B&PMP), Unité Mixte de Recherche, CNRS, INRA, Université Montpellier 2, SupAgro, Place Viala, Bat. 7, F-34060 Montpellier, France
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80
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Li C, Fu X, Qi X, Hu X, Chasteen ND, Zhao G. Protein association and dissociation regulated by ferric ion: a novel pathway for oxidative deposition of iron in pea seed ferritin. J Biol Chem 2009; 284:16743-16751. [PMID: 19398557 PMCID: PMC2719309 DOI: 10.1074/jbc.m109.011528] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2009] [Revised: 04/22/2009] [Indexed: 11/06/2022] Open
Abstract
Iron stored in phytoferritin plays an important role in the germination and early growth of seedlings. The protein is located in the amyloplast where it stores large amounts of iron as a hydrated ferric oxide mineral core within its shell-like structure. The present work was undertaken to study alternate mechanisms of core formation in pea seed ferritin (PSF). The data reveal a new mechanism for mineral core formation in PSF involving the binding and oxidation of iron at the extension peptide (EP) located on the outer surface of the protein shell. This binding induces aggregation of the protein into large assemblies of approximately 400 monomers. The bound iron is gradually translocated to the mineral core during which time the protein dissociates back into its monomeric state. Either the oxidative addition of Fe(2+) to the apoprotein to form Fe(3+) or the direct addition of Fe(3+) to apoPSF causes protein aggregation once the binding capacity of the 24 ferroxidase centers (48 Fe(3+)/shell) is exceeded. When the EP is enzymatically deleted from PSF, aggregation is not observed, and the rate of iron oxidation is significantly reduced, demonstrating that the EP is a critical structural component for iron binding, oxidation, and protein aggregation. These data point to a functional role for the extension peptide as an iron binding and ferroxidase center that contributes to mineralization of the iron core. As the iron core grows larger, the new pathway becomes less important, and Fe(2+) oxidation and deposition occurs directly on the surface of the iron core.
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Affiliation(s)
- Chaorui Li
- From the College of Food Science and Nutritional Engineering, China Agricultural University, Key Laboratory of Fruits and Vegetables Processing, Ministry of Agriculture, Beijing 100083, China
| | - Xiaoping Fu
- From the College of Food Science and Nutritional Engineering, China Agricultural University, Key Laboratory of Fruits and Vegetables Processing, Ministry of Agriculture, Beijing 100083, China
| | - Xin Qi
- National Institute of Metrology, Beijing 100013, China
| | - Xiaosong Hu
- From the College of Food Science and Nutritional Engineering, China Agricultural University, Key Laboratory of Fruits and Vegetables Processing, Ministry of Agriculture, Beijing 100083, China
| | - N Dennis Chasteen
- Department of Chemistry, University of New Hampshire, Durham, New Hampshire 03824
| | - Guanghua Zhao
- From the College of Food Science and Nutritional Engineering, China Agricultural University, Key Laboratory of Fruits and Vegetables Processing, Ministry of Agriculture, Beijing 100083, China.
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81
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Abstract
Meeting the requirement for absorbed iron is difficult for vegetarians, and their iron status often is lower than that of nonvegetarians. Beans contain ferritin in low concentrations, but it is possible to enhance this content by plant breeding or by inserting the gene for ferritin into plants, eg, soybeans. Because each ferritin molecule can bind to thousands of iron atoms, this may be a sustainable means to increase the iron contents of plants. Before such efforts are launched, it is important to determine whether iron in ferritin is bioavailable. This has been assessed in vitro by using human intestinal (Caco-2) cells and in vivo by using radiolabeled ferritin and whole-body counting in human subjects. Dietary factors affecting iron absorption, eg, ascorbic acid, phytate, and calcium, had limited effect on iron uptake from intact ferritin by Caco-2 cells, which suggests that ferritin-bound iron is absorbed via a mechanism different from that of nonheme iron. In an in vitro digestion system, ferritin was shown to be relatively resistant to proteolytic enzymes. Binding of ferritin to Caco-2 cells was shown to be saturable, and the kinetics for binding were characteristic of a receptor-mediated process. In human subjects, iron from purified soybean ferritin given in a meal was as well absorbed as iron from ferrous sulfate. In conclusion, iron is well absorbed from ferritin and may represent a means of biofortification of staple foods such as soybeans.
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Affiliation(s)
- Bo Lönnerdal
- Department of Nutrition, University of California, Davis, CA, USA.
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82
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Lukac RJ, Aluru MR, Reddy MB. Quantification of ferritin from staple food crops. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:2155-2161. [PMID: 19292462 DOI: 10.1021/jf803381d] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Ferritin-iron has been shown to be as bioavailable as ferrous sulfate in humans. Thus, biofortification to breed crops with high ferritin content is a promising strategy to alleviate the global iron deficiency problem. Although ferritin is present in all food crops, its concentration varies between species and varieties. Therefore, a successful ferritin biofortification strategy requires a method to rapidly measure ferritin concentrations in food crops. The objective of this study was to develop a simple and reliable ELISA using an anti-ferritin polyclonal antibody to detect ferritin in various crops. Crude seed extracts were found to have 10.2 +/- 1.0, 4.38 +/- 0.9, 1.2 +/- 0.3, 0.38 +/- 0.1, and 0.04 +/- 0.01 microg of ferritin/g of dry seed in red beans, white beans, wheat, maize, and brown rice, respectively. Although the measured absolute concentrations of ferritin values were low, the presented method is applicable for rapid screening for the relative ferritin concentrations of large numbers of seeds to identify and breed ferritin-rich crops.
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Affiliation(s)
- Rebecca J Lukac
- Department of Food Science and Human Nutrition, Iowa State University, Ames, Iowa 50011, USA
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83
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Ravet K, Touraine B, Boucherez J, Briat JF, Gaymard F, Cellier F. Ferritins control interaction between iron homeostasis and oxidative stress in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 57:400-12. [PMID: 18826427 DOI: 10.1111/j.1365-313x.2008.03698.x] [Citation(s) in RCA: 273] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Ferritin protein nanocages are the main iron store in mammals. They have been predicted to fulfil the same function in plants but direct evidence was lacking. To address this, a loss-of-function approach was developed in Arabidopsis. We present evidence that ferritins do not constitute the major iron pool either in seeds for seedling development or in leaves for proper functioning of the photosynthetic apparatus. Loss of ferritins in vegetative and reproductive organs resulted in sensitivity to excess iron, as shown by reduced growth and strong defects in flower development. Furthermore, the absence of ferritin led to a strong deregulation of expression of several metal transporters genes in the stalk, over-accumulation of iron in reproductive organs, and a decrease in fertility. Finally, we show that, in the absence of ferritin, plants have higher levels of reactive oxygen species, and increased activity of enzymes involved in their detoxification. Seed germination also showed higher sensitivity to pro-oxidant treatments. Arabidopsis ferritins are therefore essential to protect cells against oxidative damage.
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Affiliation(s)
- Karl Ravet
- Laboratoire de Biochimie et Physiologie Moléculaire des Plantes, UMR 5004 Agro-M/CNRS/INRA/UMII, Bat. 7, 2 Place Viala, 34060 Montpellier Cedex 1, France
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84
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Li C, Hu X, Zhao G. Two different H-type subunits from pea seed (Pisum sativum) ferritin that are responsible for fast Fe(II) oxidation. Biochimie 2009; 91:230-9. [PMID: 18984027 DOI: 10.1016/j.biochi.2008.09.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2008] [Accepted: 09/23/2008] [Indexed: 11/20/2022]
Abstract
It was established that ferritin from pea seed is composed of 26.5 and 28.0kDa subunits, but the relationship between the two subunits is unclear. The present study by both MALDI-TOF-MS and MS/MS indicated that the 28.0kDa subunit is distinct from the 26.5kDa subunit although they might share high homology in amino acid sequence, a result suggesting that pea seed ferritin is encoded by at least two genes. This result is not consistent with previous proposal that the 28.0kDa subunit is converted into the 26.5kDa subunit upon cleavage of its N-terminal sequence by free radical. Also, present results indicated that pea seed ferritin contains two different kinds of ferroxidase centers located in the 28.0 and 26.5kDa subunits, respectively. This is an exception among all known ferritins. Therefore, it is of special interest to know the role of the two subunits in iron oxidative deposition. Spectrophotometric titration and stopped flow results indicated that 48 ferrous ions can be bound and oxidized by oxygen at the ferroxidase sites, demonstrating that all of the ferroxidase sites are active and involved in fast Fe(II) oxidation. However, unlike H and L subunits in horse spleen ferritin (HoSF), both the 28.0 and 26.5 subunits lack cooperation in iron turnover into the inner cavity of pea seed ferritin.
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Affiliation(s)
- Chaorui Li
- Research Center of Fruit and Vegetable Processing, College of Food Science and Nutritional Engineering, China Agricultural University, Haidian District, Beijing, China
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85
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Busch A, Rimbauld B, Naumann B, Rensch S, Hippler M. Ferritin is required for rapid remodeling of the photosynthetic apparatus and minimizes photo-oxidative stress in response to iron availability in Chlamydomonas reinhardtii. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2008; 55:201-11. [PMID: 18363784 DOI: 10.1111/j.1365-313x.2008.03490.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Ferritin is a key player in the iron homeostasis due to its ability to store large quantities of iron. Chlamydomonas reinhardtii contains two nuclear genes for ferritin (ferr1 and ferr2) that are induced when Chlamydomonas cells are shifted to iron-deficient conditions. In response to the reduced iron availability, degradation of photosystem I (PSI) and remodeling of its light-harvesting complex occur. This active PSI degradation slows down under photo-autotrophic conditions where photosynthesis is indispensable. We observed a strong induction of ferritin correlated with the degree of PSI degradation during iron deficiency. The PSI level can be restored to normal within 24 h after iron repletion at the expense of the accumulated ferritin, indicating that the ferritin-stored iron allows fast adjustment of the photosynthetic apparatus with respect to iron availability. RNAi strains that are significantly reduced in the amount of ferritin show a striking delay in the degradation of PSI under iron deficiency. Furthermore, these strains are more susceptible to photo-oxidative stress under high-light conditions. We conclude that (i) ferritin is used to buffer the iron released by degradation of the photosynthetic complexes, (ii) the physiological status of the cell determines the strategy used to overcome the impact of iron deficiency, (iii) the availability of ferritin is important for rapid degradation of PSI under iron deficiency, and (iv) ferritin plays a protective role under photo-oxidative stress conditions.
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Affiliation(s)
- Andreas Busch
- Institute of Plant Biochemistry and Biotechnology, Department of Biology, University of Münster, Hindenburgplatz 55, 48143 Münster, Germany
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86
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Dong X, Sun Q, Wei D, Li J, Li J, Tang B, Jia Q, Hu W, Zhao Y, Hua ZC. A novel ferritin gene, SferH-5, reveals heterogeneity of the 26.5-kDa subunit of soybean (Glycine max) seed ferritin. FEBS Lett 2007; 581:5796-802. [PMID: 18037378 DOI: 10.1016/j.febslet.2007.11.049] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2007] [Revised: 11/01/2007] [Accepted: 11/12/2007] [Indexed: 11/21/2022]
Abstract
A novel ferritin cDNA, SferH-5, has been cloned from 7-day-old soybean seedlings. Putative SferH-5 has 96% identity with SferH-1 reported previously. All the five amino acid variants distributed in the mature region are not involved in highly conserved residues associated with ferroxidase activity center. We speculate that SferH-5 encodes a novel 26.5-kDa subunit of soybean seed ferritin, which is designated H-5 in this study. Recombinant H-5 was able to assemble, together with co-expressed H-2, as a functional soybean seed ferritin-like complex, H-5/H-2. Our data reveal the potential heterogeneity of the 26.5-kDa subunit of soybean seed ferritin.
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Affiliation(s)
- Xiangbai Dong
- The State Key Laboratory of Pharmaceutical, Biotechnology and Department of Biochemistry, College of Life Sciences, Nanjing University, Nanjing 210093, PR China
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87
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Masuda T, Goto F, Yoshihara T, Ezure T, Suzuki T, Kobayashi S, Shikata M, Utsumi S. Construction of homo- and heteropolymers of plant ferritin subunits using an in vitro protein expression system. Protein Expr Purif 2007; 56:237-46. [PMID: 17904862 DOI: 10.1016/j.pep.2007.07.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2007] [Revised: 07/20/2007] [Accepted: 07/27/2007] [Indexed: 11/17/2022]
Abstract
Ferritin is a class of iron storage protein composed of 24 subunits. Although many studies on gene expression analyses of plant ferritin have been conducted, the functions and oligomeric assembly of plant ferritin subunits are still largely unknown. In order to characterize the ability to form multimeric protein shells and determine the iron incorporating activity, we produced ferritin homo- and heteropolymers by expressing four cDNAs of ferritin subunits from soybean, sfer1, sfer2, sfer3, and sfer4, using an in vitro protein expression system. Using SDS-PAGE analysis followed by Prussian blue stain, homopolymers of SFER1, SFER2, and SFER3, and heteropolymers of SFER1/SFER2 and SFER1/SFER3 were detected as assembled polymers with iron incorporating activity, whereas only a small amount of SFER4 related homo- and heteropolymer was detected, suggesting that the SFER4 was not competent for oligomeric assembly, unlike every other ferritin. We conclude that certain combinations of plant ferritin subunits can form heteropolymers and that their iron incorporating activities depend on the formation of multimeric protein.
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Affiliation(s)
- Taro Masuda
- Laboratory of Food Quality Design and Development, Division of Agronomy and Horticultural Science, Graduate School of Agriculture, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.
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88
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Hoppler M, Meile L, Walczyk T. Biosynthesis, isolation and characterization of 57Fe-enriched Phaseolus vulgaris ferritin after heterologous expression in Escherichia coli. Anal Bioanal Chem 2007; 390:53-9. [DOI: 10.1007/s00216-007-1691-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2007] [Revised: 10/08/2007] [Accepted: 10/09/2007] [Indexed: 10/22/2022]
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89
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90
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Umetsu M, Man X, Okuda K, Tahereh M, Ohara S, Zhang J, Takami S, Adschiri T. Biomass-assisted Hydrothermal Synthesis of Ceria Nanoparticle —A New Application of Lignin as a Bio-nanopool—. CHEM LETT 2006. [DOI: 10.1246/cl.2006.732] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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91
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Izaguirre-Mayoral ML, Sinclair TR. Soybean genotypic difference in growth, nutrient accumulation and ultrastructure in response to manganese and iron supply in solution culture. ANNALS OF BOTANY 2005; 96:149-58. [PMID: 15897206 PMCID: PMC4246819 DOI: 10.1093/aob/mci160] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2004] [Revised: 01/17/2005] [Accepted: 03/28/2005] [Indexed: 05/02/2023]
Abstract
BACKGROUND AND AIMS The objective of this research was to characterize the physiology and cell ultrastructure of two soybean genotypes subjected to nutrient solutions with increasing concentrations of manganese (Mn) at two contrasting iron (Fe) concentrations. Genotypes 'PI227557' and 'Biloxi' were selected based on their distinctly different capacities to accumulate Mn and Fe. * METHODS Bradyrhizobium-inoculated plants were grown in hydroponic cultures in a greenhouse. Nutrient solutions were supplied with Mn concentrations ranging from 0.3 to 90 microm, at either 5 or 150 microm Fe as FeEDTA. * KEY RESULTS For both genotypes and at both Fe concentrations, Mn concentrations from 6.6 to 50 microm did not affect shoot, root and nodule mass, or leaf and nodule ureide concentration. Mn concentrations of 70 and 90 microm did not result in visible toxicity symptoms, but hindered growth and nodulation of 'Biloxi'. An Mn concentration of 0.3 microm was, however, deleterious to growth and nodulation for both genotypes, and caused an accumulation of ureides in leaves and major alterations in the ultrastructure of chloroplasts, nuclei and mitochondria, regardless of the Fe concentration. In 'PI227557', there was also a proliferation of Golgi apparatus and endoplasmic reticulum in the cytoplasm of leaf cells, and nodules showed disrupted symbiosomes lacking poly-beta-hydroxybutirate grains concomitantly with a proliferation of endoplasmic reticulum as well as arrested bacterial division. At 15 microm Fe, ferritin-like crystals were formed in the lumen of chloroplasts of 'PI227557' plants. For both genotypes, there was an antagonism between the Fe and Mn concentrations in leaves, the higher values of both microelements being detected in 'PI227557'. The absence of any detectable relationship between Fe or Mn and zinc, phosphorus and copper concentrations in leaves ruled out those micronutrients as relevant for Mn and Fe nutrition in soybeans. * CONCLUSIONS The results confirmed the greater capacity of 'PI227557' for Mn and Fe accumulation than 'Biloxi' for most nutrient treatments. Hence, 'PI227557' may be a very useful genetic resource both in developing soybean cultivars for growth on low nutrient soils and in physiological studies to understand differing approaches to nutrient accumulation in plants.
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Affiliation(s)
- M L Izaguirre-Mayoral
- Instituto Venezolano de Investigaciones Cientificas, Centro de Microbiologia y Biología Celular, Apdo Postal 21827, Caracas 1020-A, Venezuela.
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92
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Hasan MR, Morishima D, Tomita K, Katsuki M, Kotani S. Identification of a 250 kDa putative microtubule-associated protein as bovine ferritin. Evidence for a ferritin-microtubule interaction. FEBS J 2005; 272:822-31. [PMID: 15670162 DOI: 10.1111/j.1742-4658.2004.04520.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
We reported previously on the purification and partial characterization of a putative microtubule-associated protein (MAP) from bovine adrenal cortex with an approximate molecular mass of 250 kDa. The protein was expressed ubiquitously in mammalian tissues, and bound to microtubules in vitro and in vivo, but failed to promote tubulin polymerization into microtubules. In the present study, partial amino acid sequencing revealed that the protein shares an identical primary structure with the widely distributed iron storage protein, ferritin. We also found that the putative MAP and ferritin are indistinguishable from each other by electrophoretic mobility, immunological properties and morphological appearance. Moreover, the putative MAP conserves the iron storage and incorporation properties of ferritin, confirming that the two are structurally and functionally the same protein. This fact led us to investigate the interaction of ferritin with microtubules by direct electron microscopic observations. Ferritin was bound to microtubules either singly or in the form of large intermolecular aggregates. We suggest that the formation of intermolecular aggregates contributes to the intracellular stability of ferritin. The interactions between ferritin and microtubules observed in this study, in conjunction with the previous report that the administration of microtubule depolymerizing drugs increases the serum release of ferritin in rats [Ramm GA, Powell LW & Halliday JW (1996) J Gastroenterol Hepatol11, 1072-1078], support the probable role of microtubules in regulating the intracellular concentration and release of ferritin under different physiological circumstances.
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Affiliation(s)
- Mohammad R Hasan
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, Iizuka, Fukuoka, Japan.
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93
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Abstract
The ability of iron to cycle between Fe(2+) and Fe(3+) forms has led to the evolution, in different forms, of several iron-containing protein cofactors that are essential for a wide variety of cellular processes, to the extent that virtually all cells require iron for survival and prosperity. The redox properties of iron, however, also mean that this metal is potentially highly toxic and this, coupled with the extreme insolubility of Fe(3+), presents the cell with the significant problem of how to maintain this essential metal in a safe and bioavailable form. This has been overcome through the evolution of proteins capable of reversibly storing iron in the form of a Fe(3+) mineral. For several decades the ferritins have been synonymous with the function of iron storage. Within this family are subfamilies of mammalian, plant and bacterial ferritins which are all composed of 24 subunits assembled to form an essentially spherical protein with a central cavity in which the mineral is laid down. In the past few years it has become clear that other proteins, belonging to the family of DNA-binding proteins from starved cells (the Dps family), which are oligomers of 12 subunits, and to the frataxin family, which may contain up to 48 subunits, are also able to lay down a Fe(3+) mineral core. Here we present an overview of the formation of protein-coated iron minerals, with particular emphasis on the structures of the protein coats and the mechanisms by which they promote core formation. We show on the one hand that significant mechanistic similarities exist between structurally dissimilar proteins, while on the other that relatively small structural differences between otherwise similar proteins result in quite dramatic mechanistic differences.
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Affiliation(s)
- Allison Lewin
- Centre for Metalloprotein Spectroscopy and Biology, School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich, UK.
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94
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Affiliation(s)
- Jeferson Gross
- Universidade Federal do Rio Grande do Sul, Brazil; Universidade Federal do Rio Grande do Sul, Brazil
| | | | - Arthur Germano Fett-Neto
- Universidade Federal do Rio Grande do Sul, Brazil; Universidade Federal do Rio Grande do Sul, Brazil
| | - Janette Palma Fett
- Universidade Federal do Rio Grande do Sul, Brazil; Universidade Federal do Rio Grande do Sul, Brazil
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95
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Masuda T, Mikami B, Goto F, Yoshihara T, Utsumi S. Crystallization and preliminary X-ray crystallographic analysis of plant ferritin from Glycine max. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1645:113-5. [PMID: 12535618 DOI: 10.1016/s1570-9639(02)00523-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The iron storage protein ferritin from soybean (Glycine max) was expressed in E. coli and crystallized using the hanging drop vapor diffusion method with sodium tartrate as the precipitant. The crystals belong to the tetragonal I4(1)22 space group, with unit cell parameters a=b=324.0, c=182.7 A. The diffraction data were collected up to a resolution of 3.0 A with a multi-wire area detector.
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Affiliation(s)
- Taro Masuda
- Department of Bio-Science, Central Research Institute of Electric Power Industry, 1646 Abiko, Abiko-shi, 270-1194, Chiba, Japan.
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96
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Kong B, Huang HQ, Lin QM, Kim WS, Cai Z, Cao TM, Miao H, Luo DM. Purification, electrophoretic behavior, and kinetics of iron release of liver ferritin of Dasyatis akajei. JOURNAL OF PROTEIN CHEMISTRY 2003; 22:61-70. [PMID: 12739899 DOI: 10.1023/a:1023019911749] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
From the liver of fish Dasyatis akajei, ferritin has been isolated by thermal denaturation and ammonium sulfate fractionation and then further purified by anion exchange chromatography and gel exclusion chromatography. The molecular weight of the liver ferritin of D. akajei (DALF) was measured to be 400 kDa by PAGE. Moreover, SDS-PAGE experimentation indicates that protein shell of DALF consists of the H and L subunits with molecular weight of 18 and 13 kDa, respectively. Using isoelectric focusing with pH ranging from 5.0 to 6.0, the ferritin purified by the PAGE exhibited three bands with different pI values in the gel slab. Diameters of the protein shell and iron core were also investigated by transmission electron microscope and determined to be 10-12 nm and 5-8 nm, respectively. A kinetic study of DALF reveals that the rate of self-regulation of the protein shell rather than the complex surface of the iron core plays an important role in forming a process for iron release with mixed orders.
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Affiliation(s)
- Bo Kong
- Department of Biology, The Center for Analysis and Testing, The Key Laboratory of MOE for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen 361005, China
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