1
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Liziczai M, Fuchs A, Manatschal C, Dutzler R. Structural basis for metal ion transport by the human SLC11 proteins DMT1 and NRAMP1. Nat Commun 2025; 16:761. [PMID: 39824808 PMCID: PMC11742427 DOI: 10.1038/s41467-024-54705-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Accepted: 11/19/2024] [Indexed: 01/30/2025] Open
Abstract
Iron and manganese are essential nutrients whose transport across membranes is catalyzed by members of the SLC11 family. In humans, this protein family contains two paralogs, the ubiquitously expressed DMT1, which is involved in the uptake and distribution of Fe2+ and Mn2+, and NRAMP1, which participates in the resistance against infections and nutrient recycling. Despite previous studies contributing to our mechanistic understanding of the family, the structures of human SLC11 proteins and their relationship to functional properties have remained elusive. Here we describe the cryo-electron microscopy structures of DMT1 and NRAMP1 and relate them to their functional properties. We show that both proteins catalyze selective metal ion transport coupled to the symport of H+, but additionally also mediate uncoupled H+ flux. Their structures, while sharing general properties with known prokaryotic homologs, display distinct features that lead to stronger transition metal ion selectivity.
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Affiliation(s)
- Márton Liziczai
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Ariane Fuchs
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | | | - Raimund Dutzler
- Department of Biochemistry, University of Zurich, Zurich, Switzerland.
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2
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Yan H, Peng Z, Zhang H, Wang B, Xu W, He Z. Cadmium Minimization in Crops: A Trade-Off With Mineral Nutrients in Safe Breeding. PLANT, CELL & ENVIRONMENT 2025; 48:838-851. [PMID: 39351608 DOI: 10.1111/pce.15182] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2024] [Revised: 08/27/2024] [Accepted: 09/15/2024] [Indexed: 12/06/2024]
Abstract
Cadmium (Cd) contamination poses a threat to global crop safety. To address this issue, researchers mainly focused on the Cd, explored mechanism of accumulation to low-Cd breeding technologies and created several low-Cd varieties over the past decades. However, new challenges have emerged, particularly the yield reduction due to disturbances in mineral nutrient balance. The goals of breeding have been transferred from a primary focus on 'low-Cd crops' to 'low-Cd/nutrient-balanced' crops, which means limiting Cd content while maintaining other nutrient elements like iron (Fe), manganese (Mn) and zinc (Zn) at a proper content, thus to meet the future agricultural demands. Here, on a multielement perspective, we reviewed the mechanisms of Cd and mineral nutrient transport system in crops and summarized the research advances in Cd minimization through artificial mutations, natural variations and genetic engineering. Furthermore, the challenge of disruption of mineral nutrients in low-Cd crops was discussed and two potential approaches designing Cd-mineral nutrient-optimized artificial transporters and pyramiding Cd-mineral nutrient-optimized variations were proposed. Aiming at addressing these challenges, these approaches represent promising advancements in the field and offer potential pathways for future research and development in the creation of safe and high-quality crops.
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Affiliation(s)
- Huili Yan
- Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
| | - Zhimei Peng
- Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hezifan Zhang
- Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Binghan Wang
- Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Wenxiu Xu
- Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
| | - Zhenyan He
- Institute of Botany, Chinese Academy of Sciences, Beijing, China
- China National Botanical Garden, Beijing, China
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3
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Ma Y, Huang Y, Zhang W, Dong J, Zhang X, Zhu Y, Wang Y, Liu L, Xu L. RsNRAMP5, a major metal transporter, promotes cadmium influx and ROS accumulation in radish (Raphanus sativus L.). PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2025; 218:109323. [PMID: 39603032 DOI: 10.1016/j.plaphy.2024.109323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2024] [Revised: 10/28/2024] [Accepted: 11/20/2024] [Indexed: 11/29/2024]
Abstract
Arable soil contamination with heavy metals (HMs) poses a great potential threat to vegetable crops and human health. Radish (Raphanus sativus L.), an economical and popular root vegetable crop, is easily absorbed HMs by its taproot. Although the Natural Resistance-Associated Macrophage Proteins (NRAMPs) were participated in transporting a number of HMs in plants, whether and how the NRAMP genes involved in cadmium (Cd) uptake and transport remains elusive in radish. In this study, a total of nine RsNRAMP gene members were identified, which were classified into three subgroups and dispersed on six radish chromosomes. Three RsNRAMPs (RsNRAMP3, RsNRAMP4 and RsNRAMP5) displayed high expression in the vascular cambium, and they exhibited obviously Cd-induced expression, among which the expression of RsNRAMP4 and RsNRAMP5 reached to the highest level at 24h. Moreover, the RsNRAMP5 was localized to the plasma membrane and its promoter activity was dramatically induced by Cd exposure. Heterologous expression analysis indicated that over-expression of RsNRAMP5 significantly promoted the uptake of Cd, lead (Pb), iron (Fe) and manganese (Mn) in yeast cells. In addition, the transient over-expression of RsNRAMP5 promoted Cd uptake and enhanced ROS (reactive oxygen species) accumulation in radish cotyledons. These findings would expedite unraveling the molecular mechanism underlying RsNRAMP5-mediated Cd uptake and transport in radish.
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Affiliation(s)
- Yingfei Ma
- National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yudi Huang
- National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Weilan Zhang
- National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jiaheng Dong
- National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xiaoli Zhang
- National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yuelin Zhu
- National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yan Wang
- National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Liwang Liu
- National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China
| | - Liang Xu
- National Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
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4
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Inoue J, Teramoto T, Kazama T, Nakamura T. Engineering rice Nramp5 modifies cadmium and manganese uptake selectivity using yeast assay system. FRONTIERS IN PLANT SCIENCE 2024; 15:1482099. [PMID: 39634065 PMCID: PMC11614607 DOI: 10.3389/fpls.2024.1482099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2024] [Accepted: 10/30/2024] [Indexed: 12/07/2024]
Abstract
Cd is a seriously hazardous heavy metal for both plants and humans and international regulations regarding Cd intake have become stricter in recent years. Three-quarters of the Cd intake comes from plant-based foods, half of which comes from cereals. Therefore, it is anticipated that the Cd uptake efficiency of cereals, including rice, a staple crop in Asia, will be reduced. Natural resistance-associated macrophage protein (Nramp) is the principal transporter involved in the uptake and translocation of metal ions in various plants. In rice, OsNramp5 is a transporter of Mn, which is an essential micronutrient for plant growth, and is responsible for Cd uptake. Although several attempts have been made to engineer the metal uptake characteristics of OsNramp5, in many cases, both Cd and Mn uptake efficiencies are impaired. Therefore, in this study, we engineered OsNramp5 to reduce Cd uptake while retaining Mn uptake efficiency for low-Cd rice production. OsNramp5 was engineered using amino acid substitution(s) at the 232nd Ala and 235th Met of OsNramp5, which have been suggested to be key residues for metal uptake efficiency and/or selectivity by structural analyses of bacterial Nramps. The metal uptake efficiency was first analyzed using a yeast model assay system. Several mutants showed less than 8.6% Cd and more than 64.1% Mn uptake efficiency compared to the original OsNramp5. The improved metal uptake characteristics were confirmed by direct measurement of the metal content in the yeast using inductively coupled plasma optical emission spectroscopy. Notably, several mutants reduced Cd uptake efficiency to the background level while retaining more than 64.7% Mn uptake efficiency under conditions mimicking heavily polluted soils in the world. In addition, computational structural modeling suggested requirements for the spatial and chemical properties of the metal transport tunnel and metal-binding site, respectively, for Cd/Mn uptake efficiency.
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Loveridge KM, Sigala PA. Identification of a divalent metal transporter required for cellular iron metabolism in malaria parasites. Proc Natl Acad Sci U S A 2024; 121:e2411631121. [PMID: 39467134 PMCID: PMC11551425 DOI: 10.1073/pnas.2411631121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2024] [Accepted: 09/23/2024] [Indexed: 10/30/2024] Open
Abstract
Plasmodium falciparum malaria parasites invade and multiply inside red blood cells (RBCs), the most iron-rich compartment in humans. Like all cells, P. falciparum requires nutritional iron to support essential metabolic pathways, but the critical mechanisms of iron acquisition and trafficking during RBC infection have remained obscure. Parasites internalize and liberate massive amounts of heme during large-scale digestion of RBC hemoglobin within an acidic food vacuole (FV) but lack a heme oxygenase to release porphyrin-bound iron. Although most FV heme is sequestered into inert hemozoin crystals, prior studies indicate that trace heme escapes biomineralization and is susceptible to nonenzymatic degradation within the oxidizing FV environment to release labile iron. Parasites retain a homolog of divalent metal transporter 1 (DMT1), a known mammalian iron transporter, but its role in P. falciparum iron acquisition has not been tested. Our phylogenetic studies indicate that P. falciparum DMT1 (PfDMT1) retains conserved molecular features critical for metal transport. We localized this protein to the FV membrane and defined its orientation in an export-competent topology. Conditional knockdown of PfDMT1 expression is lethal to parasites, which display broad cellular defects in iron-dependent functions, including impaired apicoplast biogenesis and mitochondrial polarization. Parasites are selectively rescued from partial PfDMT1 knockdown by supplementation with exogenous iron, but not other metals. These results support a cellular paradigm whereby PfDMT1 is the molecular gatekeeper to essential iron acquisition by blood-stage malaria parasites and suggest that therapeutic targeting of PfDMT1 may be a potent antimalarial strategy.
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Affiliation(s)
- Kade M. Loveridge
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT84112
| | - Paul A. Sigala
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT84112
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6
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Hu J, Jiang Y. Evolution, classification, and mechanisms of transport, activity regulation, and substrate specificity of ZIP metal transporters. Crit Rev Biochem Mol Biol 2024; 59:245-266. [PMID: 39431645 DOI: 10.1080/10409238.2024.2405476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 08/23/2024] [Accepted: 09/13/2024] [Indexed: 10/22/2024]
Abstract
The Zrt/Irt-like protein (ZIP) family consists of ubiquitously expressed divalent d-block metal transporters that play central roles in the uptake, secretion, excretion, and distribution of several essential and toxic metals in living organisms. The past few years has witnessed rapid progress in the molecular basis of these membrane transport proteins. In this critical review, we summarize the research progress at the molecular level of the ZIP family and discuss the future prospects. Furthermore, an evolutionary path for the unique ZIP fold and a new classification of the ZIP family are proposed based on the presented structural and sequence analyses.
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Affiliation(s)
- Jian Hu
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
- Department of Chemistry, Michigan State University, East Lansing, MI, USA
| | - Yuhan Jiang
- Department of Chemistry, Michigan State University, East Lansing, MI, USA
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7
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Licht JA, Berry SP, Gutierrez MA, Gaudet R. They all rock: A systematic comparison of conformational movements in LeuT-fold transporters. Structure 2024; 32:1528-1543.e3. [PMID: 39025067 PMCID: PMC11380583 DOI: 10.1016/j.str.2024.06.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 05/30/2024] [Accepted: 06/21/2024] [Indexed: 07/20/2024]
Abstract
Many membrane transporters share the LeuT fold-two five-helix repeats inverted across the membrane plane. Despite hundreds of structures, whether distinct conformational mechanisms are supported by the LeuT fold has not been systematically determined. After annotating published LeuT-fold structures, we analyzed distance difference matrices (DDMs) for nine proteins with multiple available conformations. We identified rigid bodies and relative movements of transmembrane helices (TMs) during distinct steps of the transport cycle. In all transporters, the bundle (first two TMs of each repeat) rotates relative to the hash (third and fourth TMs). Motions of the arms (fifth TM) to close or open the intracellular and outer vestibules are common, as is a TM1a swing, with notable variations in the opening-closing motions of the outer vestibule. Our analyses suggest that LeuT-fold transporters layer distinct motions on a common bundle-hash rock and demonstrate that systematic analyses can provide new insights into large structural datasets.
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Affiliation(s)
- Jacob A Licht
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Samuel P Berry
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Michael A Gutierrez
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Rachelle Gaudet
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
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8
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Loveridge KM, Sigala PA. Identification of a divalent metal transporter required for cellular iron metabolism in malaria parasites. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.10.587216. [PMID: 38798484 PMCID: PMC11118319 DOI: 10.1101/2024.05.10.587216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Plasmodium falciparum malaria parasites invade and multiply inside red blood cells (RBCs), the most iron-rich compartment in humans. Like all cells, P. falciparum requires nutritional iron to support essential metabolic pathways, but the critical mechanisms of iron acquisition and trafficking during RBC infection have remained obscure. Parasites internalize and liberate massive amounts of heme during large-scale digestion of RBC hemoglobin within an acidic food vacuole (FV) but lack a heme oxygenase to release porphyrin-bound iron. Although most FV heme is sequestered into inert hemozoin crystals, prior studies indicate that trace heme escapes biomineralization and is susceptible to non-enzymatic degradation within the oxidizing FV environment to release labile iron. Parasites retain a homolog of divalent metal transporter 1 (DMT1), a known mammalian iron transporter, but its role in P. falciparum iron acquisition has not been tested. Our phylogenetic studies indicate that P. falciparum DMT1 (PfDMT1) retains conserved molecular features critical for metal transport. We localized this protein to the FV membrane and defined its orientation in an export-competent topology. Conditional knockdown of PfDMT1 expression is lethal to parasites, which display broad cellular defects in iron-dependent functions, including impaired apicoplast biogenesis and mitochondrial polarization. Parasites are selectively rescued from partial PfDMT1 knockdown by supplementation with exogenous iron, but not other metals. These results support a cellular paradigm whereby PfDMT1 is the molecular gatekeeper to essential iron acquisition by blood-stage malaria parasites and suggest that therapeutic targeting of PfDMT1 may be a potent antimalarial strategy.
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Affiliation(s)
- Kade M. Loveridge
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, United States
| | - Paul A. Sigala
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT, United States
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9
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Fan W, Kong Q, Chen Y, Lu F, Wang S, Zhao A. Safe utilization and remediation potential of the mulberry-silkworm system in heavy metal-contaminated lands: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:172352. [PMID: 38608900 DOI: 10.1016/j.scitotenv.2024.172352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/24/2024] [Accepted: 04/08/2024] [Indexed: 04/14/2024]
Abstract
Mulberry cultivation and silkworm rearing hold a prominent position in the agricultural industries of many Asian countries, contributing to economic growth, sustainable development, and cultural heritage preservation. Applying the soil-mulberry-silkworm system (SMSS) to heavy metal (HM)-contaminated areas is significant economically, environmentally, and socially. The ultimate goal of this paper is to review the main research progress of SMSS under HM stress, examining factors affecting its safe utilization and remediation potential for HM-contaminated soils. HM tolerance of mulberry and silkworms relates to their growth stages. Based on the standards for HM contaminants in various mulberry and silkworm products and the bioconcentration factor of HMs at different parts of SMSS, we calculated maximum safe Cd and Pb levels for SMSS application on contaminated lands. Several remediation practices demonstrated mulberry's ability to grow on barren lands, absorb various HMs, while silkworm excreta can adsorb HMs and improve soil fertility. Considering multiple factors influencing HM tolerance and accumulation, we propose a decision model to guide SMSS application in polluted areas. Finally, we discussed the potential of using molecular breeding techniques to screen or develop varieties better suited for HM-contaminated regions. However, actual pollution scenarios are often complex, requiring consideration of multiple factors. More large-scale applications are crucial to enhance the theoretical foundation for applying SMSS in HM pollution risk areas.
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Affiliation(s)
- Wei Fan
- State Key Laboratory of Resource Insects, Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400715, China
| | - Qiuyue Kong
- State Key Laboratory of Resource Insects, Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400715, China
| | - Yuane Chen
- State Key Laboratory of Resource Insects, Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400715, China
| | - Fuping Lu
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
| | - Shuchang Wang
- Environment and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571101, China
| | - Aichun Zhao
- State Key Laboratory of Resource Insects, Institute of Sericulture and Systems Biology, Southwest University, Chongqing 400715, China.
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10
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Zhao Y, Xie Q, Yang Q, Cui J, Tan W, Zhang D, Xiang J, Deng L, Guo Y, Li M, Liu L, Yan M. Genome-wide identification and evolutionary analysis of the NRAMP gene family in the AC genomes of Brassica species. BMC PLANT BIOLOGY 2024; 24:311. [PMID: 38649805 PMCID: PMC11036763 DOI: 10.1186/s12870-024-04981-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 04/03/2024] [Indexed: 04/25/2024]
Abstract
BACKGROUND Brassica napus, a hybrid resulting from the crossing of Brassica rapa and Brassica oleracea, is one of the most important oil crops. Despite its significance, B. napus productivity faces substantial challenges due to heavy metal stress, especially in response to cadmium (Cd), which poses a significant threat among heavy metals. Natural resistance-associated macrophage proteins (NRAMPs) play pivotal roles in Cd uptake and transport within plants. However, our understanding of the role of BnNRAMPs in B. napus is limited. Thus, this study aimed to conduct genome-wide identification and bioinformatics analysis of three Brassica species: B. napus, B. rapa, and B. oleracea. RESULTS A total of 37 NRAMPs were identified across the three Brassica species and classified into two distinct subfamilies based on evolutionary relationships. Conservative motif analysis revealed that motif 6 and motif 8 might significantly contribute to the differentiation between subfamily I and subfamily II within Brassica species. Evolutionary analyses and chromosome mapping revealed a reduction in the NRAMP gene family during B. napus evolutionary history, resulting in the loss of an orthologous gene derived from BoNRAMP3.2. Cis-acting element analysis suggested potential regulation of the NRAMP gene family by specific plant hormones, such as abscisic acid (ABA) and methyl jasmonate (MeJA). However, gene expression pattern analyses under hormonal or stress treatments indicated limited responsiveness of the NRAMP gene family to these treatments, warranting further experimental validation. Under Cd stress in B. napus, expression pattern analysis of the NRAMP gene family revealed a decrease in the expression levels of most BnNRAMP genes with increasing Cd concentrations. Notably, BnNRAMP5.1/5.2 exhibited a unique response pattern, being stimulated at low Cd concentrations and inhibited at high Cd concentrations, suggesting potential response mechanisms distinct from those of other NRAMP genes. CONCLUSIONS In summary, this study indicates complex molecular dynamics within the NRAMP gene family under Cd stress, suggesting potential applications in enhancing plant resilience, particularly against Cd. The findings also offer valuable insights for further understanding the functionality and regulatory mechanisms of the NRAMP gene family.
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Affiliation(s)
- Yuquan Zhao
- Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization, School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan, 411201, China
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China
- Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
| | - Qijun Xie
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China
- School of Life Science and Chemistry, Hunan University of Technology, Zhuzhou, 412007, China
| | - Qian Yang
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China
- Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
| | - Jiamin Cui
- Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization, School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan, 411201, China
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China
| | - Wenqing Tan
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China
- Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
| | - Dawei Zhang
- Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization, School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan, 411201, China
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China
| | - Jianhua Xiang
- Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization, School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan, 411201, China
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China
| | - Lichao Deng
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China
- Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
- Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
| | - Yiming Guo
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China
- Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
- Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
| | - Mei Li
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China
- Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
- Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan Academy of Agricultural Sciences, Changsha, 410125, China
| | - Lili Liu
- Hunan Key Laboratory of Economic Crops Genetic Improvement and Integrated Utilization, School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan, 411201, China.
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China.
| | - Mingli Yan
- Yuelushan Laboratory, Hongqi Road, Changsha, 410125, China.
- Crop Research Institute, Hunan Academy of Agricultural Sciences, Changsha, 410125, China.
- Hunan Engineering and Technology Research Center of Hybrid Rapeseed, Hunan Academy of Agricultural Sciences, Changsha, 410125, China.
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11
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Licht JA, Berry SP, Gutierrez MA, Gaudet R. They all rock: A systematic comparison of conformational movements in LeuT-fold transporters. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.24.577062. [PMID: 38352416 PMCID: PMC10862720 DOI: 10.1101/2024.01.24.577062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/19/2024]
Abstract
Many membrane transporters share the LeuT fold-two five-helix repeats inverted across the membrane plane. Despite hundreds of structures, whether distinct conformational mechanisms are supported by the LeuT fold has not been systematically determined. After annotating published LeuT-fold structures, we analyzed distance difference matrices (DDMs) for nine proteins with multiple available conformations. We identified rigid bodies and relative movements of transmembrane helices (TMs) during distinct steps of the transport cycle. In all transporters the bundle (first two TMs of each repeat) rotates relative to the hash (third and fourth TMs). Motions of the arms (fifth TM) to close or open the intracellular and outer vestibules are common, as is a TM1a swing, with notable variations in the opening-closing motions of the outer vestibule. Our analyses suggest that LeuT-fold transporters layer distinct motions on a common bundle-hash rock and demonstrate that systematic analyses can provide new insights into large structural datasets.
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Affiliation(s)
- Jacob A. Licht
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
| | - Samuel P. Berry
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
| | - Michael A. Gutierrez
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
- Present address: Novartis Biomedical Research, Cambridge, MA, USA
| | - Rachelle Gaudet
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
- Lead contact
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12
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Okazaki Y. Iron from the gut: the role of divalent metal transporter 1. J Clin Biochem Nutr 2024; 74:1-8. [PMID: 38292117 PMCID: PMC10822759 DOI: 10.3164/jcbn.23-47] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 10/10/2023] [Indexed: 02/01/2024] Open
Abstract
Mammalian cells contain thousands of metalloproteins and evolved systems to correctly incorporate metal cofactors into their designated sites. Among the transient metals in living cells, iron is the most abundant element that present as an iron sulfur cluster, mono- and dinuclear iron centers or heme for catalytic reactions. Iron homeostasis is tightly regulated by intestinal iron absorption in mammals owing to the lack of an iron excretive transport system, apart from superficial epithelial cell detachment and urinary outflow reabsorptive impairment. In mammals, the central site for iron absorption is in the duodenum, where the divalent metal transporter 1 is essential for iron uptake. The most notable manifestation of mutated divalent metal transporter 1 presents as iron deficiency anemia in humans. In contrast, the mutation of ferroportin, which exports iron, causes iron overload by either gain or loss of function. Furthermore, hepcidin secretion from the liver suppresses iron efflux by internalizing and degrading ferroportin; thus, the hepcidin/ferroportin axis is extensively investigated for its potential as a therapeutic target to treat iron overload. This review focuses on the divalent metal transporter 1-mediated intestinal iron uptake and hepcidin/ferroportin axis that regulate systemic iron homeostasis.
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Affiliation(s)
- Yasumasa Okazaki
- Department of Pathology and Biological Responses, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Aichi 466-8550, Japan
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13
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Qu Z, Nakanishi H. Amino Acid Residues of the Metal Transporter OsNRAMP5 Responsible for Cadmium Absorption in Rice. PLANTS (BASEL, SWITZERLAND) 2023; 12:4182. [PMID: 38140509 PMCID: PMC10748276 DOI: 10.3390/plants12244182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/02/2023] [Accepted: 12/13/2023] [Indexed: 12/24/2023]
Abstract
The transport of metals such as iron (Fe), manganese (Mn), and cadmium (Cd) in rice is highly related. Although Fe and Mn are essential elements for plant growth, Cd is a toxic element for both plants and humans. OsNRAMP5-a member of the same family as the Fe, Mn, and Cd transporter OsNRAMP1-is responsible for the transport of Mn and Cd from soil in rice. Knockout of OsNRAMP5 markedly reduces both Cd and Mn absorption, and this OsNRAMP5 knockout is indispensable for the development of low-Cd rice. However, in low-Mn environments, such plants would exhibit Mn deficiency and suppressed growth. We generated random mutations in OsNRAMP5 via error-prone PCR, and used yeast to screen for the retention of Mn absorption and the inhibition of Cd absorption. The results showed that alanine 512th is the most important amino acid residue for Cd absorption and that its substitution resulted in the absorption of Mn but not Cd.
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Affiliation(s)
| | - Hiromi Nakanishi
- Department of Global Agricultural Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan;
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Zhong S, Fang L, Li X, Liu T, Wang P, Gao R, Chen G, Yin H, Yang Y, Huang F, Li F. Roles of Chloride and Sulfate Ions in Controlling Cadmium Transport in a Soil-Rice System as Evidenced by the Cd Isotope Fingerprint. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:17920-17929. [PMID: 37755710 DOI: 10.1021/acs.est.3c04132] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
Anions accompanying inorganic fertilizers, such as chloride and sulfate ions, potentially affect the solubility, uptake, and transport of Cd to rice grains. However, the role of anions in controlling Cd transport in the soil-soil solution-Fe plaque-rice plant continuum remains poorly understood. Cd isotope ratios were applied to Cd-contaminated soil pots, hydroponic rice, and adsorption experiments with or without KCl and K2SO4 treatments to decipher transport processes in the complex soil-rice system. The chloride and sulfate ions increased the Cd concentrations in the soil solution, Fe plaque, and rice plants. Accordingly, the magnitude of positive fractionation from soil to the soil solution was less pronounced, but that between soil and Fe plaque or rice plant is barely varied. The similar isotope composition of Fe plaque and soil, and the similar fractionation magnitude between Fe plaque and the solution and between goethite and the solution, suggested that desorption-sorption between iron oxides and the solution could be important at the soil-soil solution-Fe plaque continuum. This study reveals the roles of chloride and sulfate ions: (i) induce the mobility of light Cd isotopes from soil to the soil solution, (ii) chloro-Cd and sulfato-Cd complexes contribute to Cd immobilization in the Fe plaque and uptake into roots, and (iii) facilitate second leaves/node II-to-grain Cd transport within shoots. These results provide insights into the anion-induced Cd isotope effect in the soil-rice system and the roles of anions in facilitating Cd migration and transformation.
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Affiliation(s)
- Songxiong Zhong
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Liping Fang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Xiaomin Li
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - Tongxu Liu
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Pei Wang
- College of Tropical Crops, Hainan University, Haikou 570228, China
| | - Ruichuan Gao
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Guojun Chen
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Haoming Yin
- CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Yang Yang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Fang Huang
- CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Fangbai Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
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15
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Fan P, Wu L, Wang Q, Wang Y, Luo H, Song J, Yang M, Yao H, Chen S. Physiological and molecular mechanisms of medicinal plants in response to cadmium stress: Current status and future perspective. JOURNAL OF HAZARDOUS MATERIALS 2023; 450:131008. [PMID: 36842201 DOI: 10.1016/j.jhazmat.2023.131008] [Citation(s) in RCA: 51] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/08/2023] [Accepted: 02/13/2023] [Indexed: 06/18/2023]
Abstract
Medicinal plants have a wide range of uses worldwide. However, the quality of medicinal plants is affected by severe cadmium pollution. Cadmium can reduce photosynthetic capacity, lead to plant growth retardation and oxidative stress, and affect secondary metabolism. Medicinal plants have complex mechanisms to cope with cadmium stress. On the one hand, an antioxidant system can effectively scavenge excess reactive oxygen species produced by cadmium stress. On the other hand, cadmium chelates are formed by chelating peptides and then sequestered through vacuolar compartmentalization. Cadmium has no specific transporter in plants and is generally transferred to plant tissues through competition for the transporters of divalent metal ions, such as zinc, iron, and manganese. In recent years, progress has been achieved in exploring the physiological mechanisms by which medicinal plants responding to cadmium stress. The exogenous regulation of cadmium accumulation in medicinal plants has been studied, and the aim is reducing the toxicity of cadmium. However, research into molecular mechanisms is still lagging. In this paper, we review the physiological and molecular mechanisms and regulatory networks of medicinal plants exposed to cadmium, providing a reference for the study on the responses of medicinal plants to cadmium stress.
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Affiliation(s)
- Panhui Fan
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China
| | - Liwei Wu
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China
| | - Qing Wang
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China
| | - Yu Wang
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China
| | - Hongmei Luo
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China
| | - Jingyuan Song
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China
| | - Meihua Yang
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China
| | - Hui Yao
- Key Lab of Chinese Medicine Resources Conservation, State Administration of Traditional Chinese Medicine of the People's Republic of China, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, China; Engineering Research Center of Chinese Medicine Resources, Ministry of Education, Beijing 100193, China.
| | - Shilin Chen
- Institute of Herbgenomics, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, China.
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16
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Ray S, Berry SP, Wilson EA, Zhang CH, Shekhar M, Singharoy A, Gaudet R. High-resolution structures with bound Mn 2+ and Cd 2+ map the metal import pathway in an Nramp transporter. eLife 2023; 12:e84006. [PMID: 37039477 PMCID: PMC10185341 DOI: 10.7554/elife.84006] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 04/06/2023] [Indexed: 04/12/2023] Open
Abstract
Transporters of the Nramp (Natural resistance-associated macrophage protein) family import divalent transition metal ions into cells of most organisms. By supporting metal homeostasis, Nramps prevent diseases and disorders related to metal insufficiency or overload. Previous studies revealed that Nramps take on a LeuT fold and identified the metal-binding site. We present high-resolution structures of Deinococcus radiodurans (Dra)Nramp in three stable conformations of the transport cycle revealing that global conformational changes are supported by distinct coordination geometries of its physiological substrate, Mn2+, across conformations, and by conserved networks of polar residues lining the inner and outer gates. In addition, a high-resolution Cd2+-bound structure highlights differences in how Cd2+ and Mn2+ are coordinated by DraNramp. Complementary metal binding studies using isothermal titration calorimetry with a series of mutated DraNramp proteins indicate that the thermodynamic landscape for binding and transporting physiological metals like Mn2+ is different and more robust to perturbation than for transporting the toxic Cd2+ metal. Overall, the affinity measurements and high-resolution structural information on metal substrate binding provide a foundation for understanding the substrate selectivity of essential metal ion transporters like Nramps.
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Affiliation(s)
- Shamayeeta Ray
- Department of Molecular and Cellular Biology, Harvard UniversityCambridgeUnited States
| | - Samuel P Berry
- Department of Molecular and Cellular Biology, Harvard UniversityCambridgeUnited States
| | - Eric A Wilson
- School of Molecular Sciences, Arizona State UniversityTempeUnited States
| | - Casey H Zhang
- Department of Molecular and Cellular Biology, Harvard UniversityCambridgeUnited States
| | | | - Abhishek Singharoy
- School of Molecular Sciences, Arizona State UniversityTempeUnited States
| | - Rachelle Gaudet
- Department of Molecular and Cellular Biology, Harvard UniversityCambridgeUnited States
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17
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Zhao FJ, Chang JD. A weak allele of OsNRAMP5 for safer rice. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:6009-6012. [PMID: 36255375 PMCID: PMC9578346 DOI: 10.1093/jxb/erac323] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 07/22/2022] [Indexed: 06/16/2023]
Affiliation(s)
| | - Jia-Dong Chang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
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18
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Cellier MFM. Nramp: Deprive and conquer? Front Cell Dev Biol 2022; 10:988866. [PMID: 36313567 PMCID: PMC9606685 DOI: 10.3389/fcell.2022.988866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Solute carriers 11 (Slc11) evolved from bacterial permease (MntH) to eukaryotic antibacterial defense (Nramp) while continuously mediating proton (H+)-dependent manganese (Mn2+) import. Also, Nramp horizontal gene transfer (HGT) toward bacteria led to mntH polyphyly. Prior demonstration that evolutionary rate-shifts distinguishing Slc11 from outgroup carriers dictate catalytic specificity suggested that resolving Slc11 family tree may provide a function-aware phylogenetic framework. Hence, MntH C (MC) subgroups resulted from HGTs of prototype Nramp (pNs) parologs while archetype Nramp (aNs) correlated with phagocytosis. PHI-Blast based taxonomic profiling confirmed MntH B phylogroup is confined to anaerobic bacteria vs. MntH A (MA)’s broad distribution; suggested niche-related spread of MC subgroups; established that MA-variant MH, which carries ‘eukaryotic signature’ marks, predominates in archaea. Slc11 phylogeny shows MH is sister to Nramp. Site-specific analysis of Slc11 charge network known to interact with the protonmotive force demonstrates sequential rate-shifts that recapitulate Slc11 evolution. 3D mapping of similarly coevolved sites across Slc11 hydrophobic core revealed successive targeting of discrete areas. The data imply that pN HGT could advantage recipient bacteria for H+-dependent Mn2+ acquisition and Alphafold 3D models suggest conformational divergence among MC subgroups. It is proposed that Slc11 originated as a bacterial stress resistance function allowing Mn2+-dependent persistence in conditions adverse for growth, and that archaeal MH could contribute to eukaryogenesis as a Mn2+ sequestering defense perhaps favoring intracellular growth-competent bacteria.
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19
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López-Lorca VM, Molina-Luzón MJ, Ferrol N. Characterization of the NRAMP Gene Family in the Arbuscular Mycorrhizal Fungus Rhizophagus irregularis. J Fungi (Basel) 2022; 8:jof8060592. [PMID: 35736075 PMCID: PMC9224570 DOI: 10.3390/jof8060592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/18/2022] [Accepted: 05/25/2022] [Indexed: 12/04/2022] Open
Abstract
Transporters of the NRAMP family are ubiquitous metal-transition transporters, playing a key role in metal homeostasis, especially in Mn and Fe homeostasis. In this work, we report the characterization of the NRAMP family members (RiSMF1, RiSMF2, RiSMF3.1 and RiSMF3.2) of the arbuscular mycorrhizal (AM) fungus Rhizophagus irregularis. Phylogenetic analysis of the NRAMP sequences of different AM fungi showed that they are classified in two groups, which probably diverged early in their evolution. Functional analyses in yeast revealed that RiSMF3.2 encodes a protein mediating Mn and Fe transport from the environment. Gene-expression analyses by RT-qPCR showed that the RiSMF genes are differentially expressed in the extraradical (ERM) and intraradical (IRM) mycelium and differentially regulated by Mn and Fe availability. Mn starvation decreased RiSMF1 transcript levels in the ERM but increased RiSMF3.1 expression in the IRM. In the ERM, RiSMF1 expression was up-regulated by Fe deficiency, suggesting a role for its encoded protein in Fe-deficiency alleviation. Expression of RiSMF3.2 in the ERM was up-regulated at the early stages of Fe toxicity but down-regulated at later stages. These data suggest a role for RiSMF3.2 not only in Fe transport but also as a sensor of high external-Fe concentrations. Both Mn- and Fe-deficient conditions affected ERM development. While Mn deficiency increased hyphal length, Fe deficiency reduced sporulation.
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20
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Xu J, Qin X, Ni Z, Chen F, Fu X, Yu F. Identification of Zinc Efficiency-Associated Loci ( ZEALs) and Candidate Genes for Zn Deficiency Tolerance of Two Recombination Inbred Line Populations in Maize. Int J Mol Sci 2022; 23:ijms23094852. [PMID: 35563244 PMCID: PMC9106061 DOI: 10.3390/ijms23094852] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 04/02/2022] [Accepted: 04/18/2022] [Indexed: 01/26/2023] Open
Abstract
Zinc (Zn) deficiency is one of the most common micronutrient disorders in cereal plants, greatly impairing crop productivity and nutritional quality. Identifying the genes associated with Zn deficiency tolerance is the basis for understanding the genetic mechanism conferring tolerance. In this study, the K22×BY815 and DAN340×K22 recombination inbred line (RIL) populations, which were derived from Zn-inefficient and Zn-efficient inbred lines, were utilized to detect the quantitative trait loci (QTLs) associated with Zn deficiency tolerance and to further identify candidate genes within these loci. The BLUP (Best Linear Unbiased Prediction) values under Zn-deficient condition (-Zn) and the ratios of the BLUP values under Zn deficient condition to the BLUP values under Zn-sufficient condition (-Zn/CK) were used to perform linkage mapping. In QTL analysis, 21 QTLs and 33 QTLs controlling the Zn score, plant height, shoot and root dry weight, and root-to-shoot ratio were detected in the K22×BY815 population and the DAN340×K22 population, explaining 5.5–16.6% and 4.2–23.3% of phenotypic variation, respectively. In addition, seventeen candidate genes associated with the mechanisms underlying Zn deficiency tolerance were identified in QTL colocalizations or the single loci, including the genes involved in the uptake, transport, and redistribution of Zn (ZmIRT1, ZmHMAs, ZmNRAMP6, ZmVIT, ZmNAS3, ZmDMAS1, ZmTOM3), and the genes participating in the auxin and ethylene signal pathways (ZmAFBs, ZmIAA17, ZmETR, ZmEIN2, ZmEIN3, ZmCTR3, ZmEBF1). Our findings will broaden the understanding of the genetic structure of the tolerance to Zn deficiency in maize.
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Affiliation(s)
- Jianqin Xu
- Key Laboratory of Plant-Soil Interaction (MOE), Centre for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; (J.X.); (X.Q.); (F.C.)
| | - Xiaoxin Qin
- Key Laboratory of Plant-Soil Interaction (MOE), Centre for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; (J.X.); (X.Q.); (F.C.)
| | - Zhongfu Ni
- State Key Laboratory for Agrobiotechnology, Key Laboratory of Crop Heterosis and Utilization (MOE), Key Laboratory of Crop Genetic Improvement, China Agricultural University, Beijing 100193, China;
| | - Fanjun Chen
- Key Laboratory of Plant-Soil Interaction (MOE), Centre for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; (J.X.); (X.Q.); (F.C.)
| | - Xiuyi Fu
- Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding, Maize Research Center, Beijing Academy of Agriculture & Forestry Science (BAAFS), Beijing 100097, China;
| | - Futong Yu
- Key Laboratory of Plant-Soil Interaction (MOE), Centre for Resources, Environment and Food Security, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; (J.X.); (X.Q.); (F.C.)
- Correspondence:
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21
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Zhong S, Li X, Li F, Huang Y, Liu T, Yin H, Qiao J, Chen G, Huang F. Cadmium uptake and transport processes in rice revealed by stable isotope fractionation and Cd-related gene expression. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150633. [PMID: 34592274 DOI: 10.1016/j.scitotenv.2021.150633] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 09/23/2021] [Accepted: 09/23/2021] [Indexed: 06/13/2023]
Abstract
Multiple processes are involved in Cd transfer in rice plants, including root uptake, xylem loading, and immobilization. These processes can be mediated by membrane transporters and can alter Cd speciation by binding Cd to different organic ligands. However, it remains unclear which processes control Cd transport in rice in response to different watering conditions in soil. Herein, Cd isotope fractionation and Cd-related gene expression were employed to investigate the key regulatory mechanisms during uptake, root-to-shoot, and stem-to-leaf transport of Cd in rice grown in pot experiments with Cd-contaminated soil under flooded and non-flooded conditions, respectively. The results showed that soil flooding decreased the Cd concentration in soil porewater and, thereby, Cd uptake and transport in rice. Cd isotopes fractionated negatively from soil porewater to the whole rice (flooded: ∆114/110Cdrice-porewater = -0.15‰, non-flooded: ∆114/110Cdrice-porewater = -0.39‰), suggesting that Cd transporters preferentially absorbed light Cd isotopes. The non-flooded treatment revealed an upregulated expression of OsNRAMP1 and OsNRAMP5 genes compared to the flooded treatment, which may partially contribute to its more pronounced porewater-to-rice fractionation. Cd isotopes fractionated positively from roots to shoots under flooded conditions (∆114/110Cdshoot-root = 0.19‰). However, a reverse direction of fractionation was observed under non-flooded conditions (∆114/110Cdshoot-root = -0.67‰), which was associated with the substantial upregulation of CAL1 in roots, facilitating xylem loading of Cd-CAL1 complexes with lighter isotopes. After being transported to the shoots, the majority of Cd were detained in stems (44%-55%), which were strongly enriched in lighter isotopes than in the leaves (∆114/110Cdleaf-stem = 0.77 to 1.01‰). Besides the Cd-CAL1 transported from the roots, the expression of OsPCS1 and OsHMA3 in the stems could also favor the enrichment of Cd-PCs with lighter isotopes, leaving heavier isotopes to be transported to the leaves. The higher expression levels of OsMT1e in older leaves than in younger leaves implied that Cd immobilization via binding to metallothioneins like OsMT1e may favor the enrichment of lighter isotopes in older leaves. The non-flooded treatment showed lighter Cd isotopes in younger leaves than the flooded treatment, suggesting that more Cd-CAL1 in the stems and Cd-PCs in the older leaves might be transported to the younger leaves under non-flooded conditions. Our results demonstrate that isotopically light Cd can be preferentially transported from roots to shoots when more Cd is absorbed by rice under non-flooded conditions, and isotope fractionation signature together with gene expression quantification has the potential to provide a better understanding of the key processes regulating Cd transfer in rice.
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Affiliation(s)
- Songxiong Zhong
- Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaomin Li
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China.
| | - Fangbai Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Yingmei Huang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Tongxu Liu
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Haoming Yin
- CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Jiangtao Qiao
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Guojun Chen
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Fang Huang
- CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
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22
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Ramanadane K, Straub MS, Dutzler R, Manatschal C. Structural and functional properties of a magnesium transporter of the SLC11/NRAMP family. eLife 2022; 11:74589. [PMID: 35001872 PMCID: PMC8806188 DOI: 10.7554/elife.74589] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Accepted: 12/17/2021] [Indexed: 11/13/2022] Open
Abstract
Members of the ubiquitous SLC11/NRAMP family catalyze the uptake of divalent transition metal ions into cells. They have evolved to efficiently select these trace elements from a large pool of Ca2+ and Mg2+, which are both orders of magnitude more abundant, and to concentrate them in the cytoplasm aided by the cotransport of H+ serving as energy source. In the present study, we have characterized a member of a distant clade of the family found in prokaryotes, termed NRMTs, that were proposed to function as transporters of Mg2+. The protein transports Mg2+ and Mn2+ but not Ca2+ by a mechanism that is not coupled to H+. Structures determined by cryo-EM and X-ray crystallography revealed a generally similar protein architecture compared to classical NRAMPs, with a restructured ion binding site whose increased volume provides suitable interactions with ions that likely have retained much of their hydration shell.
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Affiliation(s)
| | - Monique S Straub
- Department of Biochemistry, University of Zurich, Zürich, Switzerland
| | - Raimund Dutzler
- Department of Biochemistry, University of Zurich, Zürich, Switzerland
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Chen Y, Li G, Yang J, Zhao X, Sun Z, Hou H. Role of Nramp transporter genes of Spirodela polyrhiza in cadmium accumulation. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 227:112907. [PMID: 34673410 DOI: 10.1016/j.ecoenv.2021.112907] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 10/05/2021] [Accepted: 10/12/2021] [Indexed: 06/13/2023]
Abstract
As a pollutant, Cd causes severe impact to the environment and damages living organisms. It can be uptaken from the environment by the natural resistance-associated macrophage protein (Nramp) in plants. However, the ion absorption function of Nramp transporter genes in Spirodela polyrhiza has not been reported. In this study, SpNramp1, SpNramp2, and SpNramp3 from S. polyrhiza were cloned and their functions were analyzed in S. polyrhiza and yeast. Growth parameters and physicochemical indices of wild-type and transgenic lines were measured under Cd stress. Results revealed that SpNramp1, SpNramp2, and SpNramp3 were identified as plasma membrane-localized transporters, and their roles in transporting Cd were verified in yeast. In S. polyrhiza, SpNramp1 overexpression significantly increased the content of Cd, Fe, Mn, and fresh weight. SpNramp2 overexpression increased Mn and Cd. SpNramp3 overexpression increased Fe and Mn concentrations. These results indicate that SpNramp1, SpNramp2, and SpNramp3 had a different preference for ion absorption. Two S. polyrhiza transgenic lines (OE1 and OE3) were obtained. One of them (OE1) showed a stronger accumulation ability, and the other one (OE3) exhibited tolerance capacity to Cd. This study provides new insight into the functions of SpNramp1, SpNramp2, and SpNramp3 and obtains important enrichment lines (OE1) for manipulating Cd accumulation, phytoremediation, and ecological safety.
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Affiliation(s)
- Yan Chen
- The State Key Laboratory of Freshwater Ecology and Biotechnology, The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Gaojie Li
- The State Key Laboratory of Freshwater Ecology and Biotechnology, The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingjing Yang
- The State Key Laboratory of Freshwater Ecology and Biotechnology, The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xuyao Zhao
- The State Key Laboratory of Freshwater Ecology and Biotechnology, The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China; University of Chinese Academy of Sciences, Beijing 100049, China; College of Environment and Chemical Engineering, Pingdingshan University, Pingdingshan 467000, Henan, China
| | - Zuoliang Sun
- The State Key Laboratory of Freshwater Ecology and Biotechnology, The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hongwei Hou
- The State Key Laboratory of Freshwater Ecology and Biotechnology, The Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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24
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He J, Rössner N, Hoang MTT, Alejandro S, Peiter E. Transport, functions, and interaction of calcium and manganese in plant organellar compartments. PLANT PHYSIOLOGY 2021; 187:1940-1972. [PMID: 35235665 PMCID: PMC8890496 DOI: 10.1093/plphys/kiab122] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/02/2021] [Indexed: 05/05/2023]
Abstract
Calcium (Ca2+) and manganese (Mn2+) are essential elements for plants and have similar ionic radii and binding coordination. They are assigned specific functions within organelles, but share many transport mechanisms to cross organellar membranes. Despite their points of interaction, those elements are usually investigated and reviewed separately. This review takes them out of this isolation. It highlights our current mechanistic understanding and points to open questions of their functions, their transport, and their interplay in the endoplasmic reticulum (ER), vesicular compartments (Golgi apparatus, trans-Golgi network, pre-vacuolar compartment), vacuoles, chloroplasts, mitochondria, and peroxisomes. Complex processes demanding these cations, such as Mn2+-dependent glycosylation or systemic Ca2+ signaling, are covered in some detail if they have not been reviewed recently or if recent findings add to current models. The function of Ca2+ as signaling agent released from organelles into the cytosol and within the organelles themselves is a recurrent theme of this review, again keeping the interference by Mn2+ in mind. The involvement of organellar channels [e.g. glutamate receptor-likes (GLR), cyclic nucleotide-gated channels (CNGC), mitochondrial conductivity units (MCU), and two-pore channel1 (TPC1)], transporters (e.g. natural resistance-associated macrophage proteins (NRAMP), Ca2+ exchangers (CAX), metal tolerance proteins (MTP), and bivalent cation transporters (BICAT)], and pumps [autoinhibited Ca2+-ATPases (ACA) and ER Ca2+-ATPases (ECA)] in the import and export of organellar Ca2+ and Mn2+ is scrutinized, whereby current controversial issues are pointed out. Mechanisms in animals and yeast are taken into account where they may provide a blueprint for processes in plants, in particular, with respect to tunable molecular mechanisms of Ca2+ versus Mn2+ selectivity.
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Affiliation(s)
- Jie He
- Faculty of Natural Sciences III, Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, D-06099 Halle (Saale), Germany
| | - Nico Rössner
- Faculty of Natural Sciences III, Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, D-06099 Halle (Saale), Germany
| | - Minh T T Hoang
- Faculty of Natural Sciences III, Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, D-06099 Halle (Saale), Germany
| | - Santiago Alejandro
- Faculty of Natural Sciences III, Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, D-06099 Halle (Saale), Germany
| | - Edgar Peiter
- Faculty of Natural Sciences III, Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, D-06099 Halle (Saale), Germany
- Author for communication:
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25
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Puccio T, Kunka KS, An SS, Kitten T. Contribution of a ZIP-family protein to manganese uptake and infective endocarditis virulence in Streptococcus sanguinis. Mol Microbiol 2021; 117:353-374. [PMID: 34855265 PMCID: PMC8844249 DOI: 10.1111/mmi.14853] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 11/24/2021] [Accepted: 11/30/2021] [Indexed: 01/18/2023]
Abstract
Streptococcus sanguinis is an important cause of infective endocarditis. In strain SK36, the ABC‐family manganese transporter, SsaACB, is essential for virulence. We have now identified a ZIP‐family protein, TmpA, as a secondary manganese transporter. A tmpA mutant had no phenotype, but a ΔssaACB ΔtmpA mutant was more attenuated for serum growth and for virulence in a rabbit model than its ΔssaACB parent. The growth of both mutants was restored by supplemental manganese, but the ΔssaACB ΔtmpA mutant required twenty‐fold more and accumulated less. Although ZIP‐family proteins are known for zinc and iron transport, TmpA‐mediated transport of either metal was minimal. While ssaACB appears ubiquitous in St. sanguinis, tmpA was present in a majority of strains and a mntH gene encoding an NRAMP‐family transporter was identified in relatively few, including VMC66. As in SK36, deletion of ssaACB greatly diminished VMC66 endocarditis virulence and serum growth, and deletion of tmpA from this mutant diminished virulence further. Virulence was not significantly altered by deletion of mntH from either VMC66 or its ΔssaACB mutant. This and the accompanying paper together suggest that SsaACB is of primary importance for endocarditis virulence while secondary transporters TmpA and MntH contribute to growth under differing conditions.
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Affiliation(s)
- Tanya Puccio
- Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, Virginia, USA
| | - Karina S Kunka
- Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, Virginia, USA
| | - Seon-Sook An
- Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, Virginia, USA
| | - Todd Kitten
- Philips Institute for Oral Health Research, Virginia Commonwealth University School of Dentistry, Richmond, Virginia, USA
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26
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Wang K, Yu H, Zhang X, Ye D, Huang H, Wang Y, Zheng Z, Li T. A transcriptomic view of cadmium retention in roots of cadmium-safe rice line (Oryza sativa L.). JOURNAL OF HAZARDOUS MATERIALS 2021; 418:126379. [PMID: 34329031 DOI: 10.1016/j.jhazmat.2021.126379] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 06/13/2023]
Abstract
A better understanding of the mechanisms controlling cadmium (Cd) accumulation in rice will benefit the development of strategies to minimize Cd accumulation in grains. A Cd-safe rice line designated D62B accumulated less than 0.2 mg Cd kg-1 in brown rice due to its strong capacity for Cd retention in roots. Here transcriptomic was used to clarify the underlying mechanisms of Cd response in roots of D62B compared with a high Cd-accumulating line (Wujin4B). There were 777, 1058 differentially expressed genes (DEGs) in D62B and Wujin4B, respectively, when exposed to Cd. The functions of DEGs were clearly line-specific. Cell wall biosynthesis responded more intensively to Cd stress in D62B, facilitating Cd restriction. Meanwhile, more glutathione (GSH) and phytochelatins synthesized in D62B with the upregulation of sulphur and GSH metabolism. Besides, membrane proteins played critical roles in Cd response in D62B, whereas 18 terms involved in regulation were enriched in Wujin4B. Exogenous GSH further induced the expression of genes related to GSH metabolism and cell wall biosynthesis, leading to the retention of more Cd. Great responsiveness of cell wall biosynthesis and GSH metabolism could be considered the most important specific mechanisms for Cd retention in the roots of Cd-safe rice line.
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Affiliation(s)
- Keji Wang
- College of Resource, Sichuan Agricultural University, 211 Huimin Road, Chengdu, Sichuan 611130, China
| | - Haiying Yu
- College of Resource, Sichuan Agricultural University, 211 Huimin Road, Chengdu, Sichuan 611130, China
| | - Xizhou Zhang
- College of Resource, Sichuan Agricultural University, 211 Huimin Road, Chengdu, Sichuan 611130, China
| | - Daihua Ye
- College of Resource, Sichuan Agricultural University, 211 Huimin Road, Chengdu, Sichuan 611130, China
| | - Huagang Huang
- College of Resource, Sichuan Agricultural University, 211 Huimin Road, Chengdu, Sichuan 611130, China
| | - Yongdong Wang
- College of Resource, Sichuan Agricultural University, 211 Huimin Road, Chengdu, Sichuan 611130, China
| | - Zicheng Zheng
- College of Resource, Sichuan Agricultural University, 211 Huimin Road, Chengdu, Sichuan 611130, China
| | - Tingxuan Li
- College of Resource, Sichuan Agricultural University, 211 Huimin Road, Chengdu, Sichuan 611130, China.
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27
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Sharma P, Tóth V, Hyland EM, Law CJ. Characterization of the substrate binding site of an iron detoxifying membrane transporter from Plasmodium falciparum. Malar J 2021; 20:295. [PMID: 34193175 PMCID: PMC8247066 DOI: 10.1186/s12936-021-03827-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 06/17/2021] [Indexed: 11/10/2022] Open
Abstract
Background Plasmodium species are entirely dependent upon their host as a source of essential iron. Although it is an indispensable micronutrient, oxidation of excess ferrous iron to the ferric state in the cell cytoplasm can produce reactive oxygen species that are cytotoxic. The malaria parasite must therefore carefully regulate the processes involved in iron acquisition and storage. A 273 amino acid membrane transporter that is a member of the vacuolar iron transporter (VIT) family and an orthologue of the yeast Ca2+-sensitive cross complementer (CCC1) protein plays a major role in cytosolic iron detoxification of Plasmodium species and functions in transport of ferrous iron ions into the endoplasmic reticulum for storage. While this transporter, termed PfVIT, is not critical for viability of the parasite evidence from studies of mice infected with VIT-deficient Plasmodium suggests it could still provide an efficient target for chemoprophylactic treatment of malaria. Individual amino acid residues that constitute the Fe2+ binding site of the protein were identified to better understand the structural basis of substrate recognition and binding by PfVIT. Methods Using the crystal structure of a recently published plant VIT as a template, a high-quality homology model of PfVIT was constructed to identify the amino acid composition of the transporter’s substrate binding site and to act as a guide for subsequent mutagenesis studies. To test the effect of mutation of the substrate binding-site residues on PfVIT function a yeast complementation assay assessed the ability of overexpressed, recombinant wild type and mutant PfVIT to rescue an iron-sensitive deletion strain (ccc1∆) of Saccharomyces cerevisiae yeast from the toxic effects of a high concentration of extracellular iron. Results The combined in silico and mutagenesis approach identified a methionine residue located within the cytoplasmic metal binding domain of the transporter as essential for PfVIT function and provided insight into the structural basis for the Fe2+-selectivity of the protein. Conclusion The structural model of the metal binding site of PfVIT opens the door for rational design of therapeutics to interfere with iron homeostasis within the malaria parasite. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-03827-7.
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Affiliation(s)
- Pragya Sharma
- School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL, UK
| | - Veronika Tóth
- School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL, UK
| | - Edel M Hyland
- School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL, UK
| | - Christopher J Law
- School of Biological Sciences, Queen's University Belfast, 19 Chlorine Gardens, Belfast, BT9 5DL, UK.
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28
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Genome-Wide Identification of the Nramp Gene Family in Spirodela polyrhiza and Expression Analysis under Cadmium Stress. Int J Mol Sci 2021; 22:ijms22126414. [PMID: 34203933 PMCID: PMC8232720 DOI: 10.3390/ijms22126414] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 05/18/2021] [Accepted: 05/28/2021] [Indexed: 11/29/2022] Open
Abstract
Natural resistance-associated macrophage proteins (Nramps) are specific metal transporters in plants with different functions among various species. The evolutionary and functional information of the Nramp gene family in Spirodela polyrhiza has not been previously reported in detail. To identify the Nramp genes in S. polyrhiza, we performed genome-wide identification, characterization, classification, and cis-elements analysis among 22 species with 138 amino acid sequences. We also conducted chromosomal localization and analyzed the synteny relationship, promoter, subcellular localization, and expression patterns in S. polyrhiza. β-Glucuronidase staining indicated that SpNramp1 and SpNramp3 mainly accumulated in the root and joint between mother and daughter frond. Moreover, SpNramp1 was also widely displayed in the frond. SpNramp2 was intensively distributed in the root and frond. Quantitative real-time PCR results proved that the SpNramp gene expression level was influenced by Cd stress, especially in response to Fe or Mn deficiency. The study provides detailed information on the SpNramp gene family and their distribution and expression, laying a beneficial foundation for functional research.
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29
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Martinelli A, Rice ML, Talcott JB, Diaz R, Smith S, Raza MH, Snowling MJ, Hulme C, Stein J, Hayiou-Thomas ME, Hawi Z, Kent L, Pitt SJ, Newbury DF, Paracchini S. A rare missense variant in the ATP2C2 gene is associated with language impairment and related measures. Hum Mol Genet 2021; 30:1160-1171. [PMID: 33864365 PMCID: PMC8188402 DOI: 10.1093/hmg/ddab111] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 04/09/2021] [Accepted: 04/12/2021] [Indexed: 01/02/2023] Open
Abstract
At least 5% of children present unexpected difficulties in expressing and understanding spoken language. This condition is highly heritable and often co-occurs with other neurodevelopmental disorders such as dyslexia and ADHD. Through an exome sequencing analysis, we identified a rare missense variant (chr16:84405221, GRCh38.p12) in the ATP2C2 gene. ATP2C2 was implicated in language disorders by linkage and association studies, and exactly the same variant was reported previously in a different exome sequencing study for language impairment (LI). We followed up this finding by genotyping the mutation in cohorts selected for LI and comorbid disorders. We found that the variant had a higher frequency in LI cases (1.8%, N = 360) compared with cohorts selected for dyslexia (0.8%, N = 520) and ADHD (0.7%, N = 150), which presented frequencies comparable to reference databases (0.9%, N = 24 046 gnomAD controls). Additionally, we observed that carriers of the rare variant identified from a general population cohort (N = 42, ALSPAC cohort) presented, as a group, lower scores on a range of reading and language-related measures compared to controls (N = 1825; minimum P = 0.002 for non-word reading). ATP2C2 encodes for an ATPase (SPCA2) that transports calcium and manganese ions into the Golgi lumen. Our functional characterization suggested that the rare variant influences the ATPase activity of SPCA2. Thus, our results further support the role of ATP2C2 locus in language-related phenotypes and pinpoint the possible effects of a specific rare variant at molecular level.
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Affiliation(s)
| | - Mabel L Rice
- Child Language Doctoral Program, University of Kansas, Lawrence, KS, USA
| | - Joel B Talcott
- Aston Brain Centre, School of Life and Health Sciences, Aston University, Birmingham, UK
| | - Rebeca Diaz
- School of Medicine, University of St Andrews, St Andrews, UK
| | - Shelley Smith
- Department of Neurological Sciences, University of Nebraska Medical Center, Lincoln, NE, USA
| | | | - Margaret J Snowling
- Department of Experimental Psychology and St John's College, University of Oxford, Oxford, UK
| | - Charles Hulme
- Department of Education, University of Oxford, Oxford, UK
| | - John Stein
- Department of Physiology, University of Oxford, Oxford, UK
| | | | - Ziarih Hawi
- Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, VIC, Australia
| | - Lindsey Kent
- School of Medicine, University of St Andrews, St Andrews, UK
| | - Samantha J Pitt
- School of Medicine, University of St Andrews, St Andrews, UK
| | - Dianne F Newbury
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, UK
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30
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Molecular Mechanism of Nramp-Family Transition Metal Transport. J Mol Biol 2021; 433:166991. [PMID: 33865868 DOI: 10.1016/j.jmb.2021.166991] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 04/02/2021] [Accepted: 04/05/2021] [Indexed: 02/06/2023]
Abstract
The Natural resistance-associated macrophage protein (Nramp) family of transition metal transporters enables uptake and trafficking of essential micronutrients that all organisms must acquire to survive. Two decades after Nramps were identified as proton-driven, voltage-dependent secondary transporters, multiple Nramp crystal structures have begun to illustrate the fine details of the transport process and provide a new framework for understanding a wealth of preexisting biochemical data. Here we review the relevant literature pertaining to Nramps' biological roles and especially their conserved molecular mechanism, including our updated understanding of conformational change, metal binding and transport, substrate selectivity, proton transport, proton-metal coupling, and voltage dependence. We ultimately describe how the Nramp family has adapted the LeuT fold common to many secondary transporters to provide selective transition-metal transport with a mechanism that deviates from the canonical model of symport.
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31
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Sassa M, Takagi T, Kinjo A, Yoshioka Y, Zayasu Y, Shinzato C, Kanda S, Murakami-Sugihara N, Shirai K, Inoue K. Divalent metal transporter-related protein restricts animals to marine habitats. Commun Biol 2021; 4:463. [PMID: 33846549 PMCID: PMC8041893 DOI: 10.1038/s42003-021-01984-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 03/12/2021] [Indexed: 12/30/2022] Open
Abstract
Utilization and regulation of metals from seawater by marine organisms are important physiological processes. To better understand metal regulation, we searched the crown-of-thorns starfish genome for the divalent metal transporter (DMT) gene, a membrane protein responsible for uptake of divalent cations. We found two DMT-like sequences. One is an ortholog of vertebrate DMT, but the other is an unknown protein, which we named DMT-related protein (DMTRP). Functional analysis using a yeast expression system demonstrated that DMT transports various metals, like known DMTs, but DMTRP does not. In contrast, DMTRP reduced the intracellular concentration of some metals, especially zinc, suggesting its involvement in negative regulation of metal uptake. Phylogenetic distribution of the DMTRP gene in various metazoans, including sponges, protostomes, and deuterostomes, indicates that it originated early in metazoan evolution. However, the DMTRP gene is only retained in marine species, and its loss seems to have occurred independently in ecdysozoan and vertebrate lineages from which major freshwater and land animals appeared. DMTRP may be an evolutionary and ecological limitation, restricting organisms that possess it to marine habitats, whereas its loss may have allowed other organisms to invade freshwater and terrestrial habitats. Mieko Sassa et al. report a novel divalent metal transporter protein (DMTRP) in the crown-of-thorns starfish genome and determine that all organisms with a DMTRP gene are located in marine habitats. They also show in a functional yeast system that DMTRP can prevent uptake of certain metals, bringing insight into the evolution of metal regulation for marine organisms.
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Affiliation(s)
- Mieko Sassa
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa-shi, Chiba, Japan. .,Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa-shi, Chiba, Japan.
| | - Toshiyuki Takagi
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa-shi, Chiba, Japan
| | - Azusa Kinjo
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa-shi, Chiba, Japan
| | - Yuki Yoshioka
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa-shi, Chiba, Japan.,Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa-shi, Chiba, Japan
| | - Yuna Zayasu
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Kunigami-gun, Okinawa, Japan
| | - Chuya Shinzato
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa-shi, Chiba, Japan
| | - Shinji Kanda
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa-shi, Chiba, Japan
| | | | - Kotaro Shirai
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa-shi, Chiba, Japan
| | - Koji Inoue
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa-shi, Chiba, Japan.,Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa-shi, Chiba, Japan
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Devanna BN, Jaswal R, Singh PK, Kapoor R, Jain P, Kumar G, Sharma Y, Samantaray S, Sharma TR. Role of transporters in plant disease resistance. PHYSIOLOGIA PLANTARUM 2021; 171:849-867. [PMID: 33639002 DOI: 10.1111/ppl.13377] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 02/14/2021] [Accepted: 02/22/2021] [Indexed: 05/11/2023]
Abstract
Plants being sessile have evolved numerous mechanisms to meet the changing environmental and growth conditions. Plant pathogens are responsible for devastating disease epidemics in many species. Transporter proteins are an integral part of plant growth and development, and several studies have documented their role in pathogen disease resistance. In this review, we analyze the studies on genome-wide identifications of plant transporters like sugars will eventually be exported transporters (SWEET), multidrug and toxic compound extrusion (MATE) transporters, ATP-binding cassette (ABC) transporters, natural resistance-associated macrophage proteins (NRAMP), and sugar transport proteins (STPs), all having a significant role in plant disease resistance. The mechanism of action of these transporters, their solute specificity, and the potential application of recent molecular biology approaches deploying these transporters for the development of disease-resistant plants are also discussed. The applications of genome editing tools, such as CRIPSR/Cas9, are also presented. Altogether the information included in this article gives a better understanding of the role of transporter proteins during plant-pathogen interaction.
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Affiliation(s)
| | - Rajdeep Jaswal
- National Agri-Food Biotechnology Institute, Mohali, India
| | | | - Ritu Kapoor
- National Agri-Food Biotechnology Institute, Mohali, India
| | - Priyanka Jain
- ICAR-National Institute for Plant Biotechnology, New Delhi, India
| | - Gulshan Kumar
- National Agri-Food Biotechnology Institute, Mohali, India
| | - Yogesh Sharma
- National Agri-Food Biotechnology Institute, Mohali, India
| | | | - Tilak R Sharma
- Indian Council of Agricultural Research, Division of Crop Science, New Delhi, India
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33
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Osman D, Cooke A, Young TR, Deery E, Robinson NJ, Warren MJ. The requirement for cobalt in vitamin B 12: A paradigm for protein metalation. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2021; 1868:118896. [PMID: 33096143 PMCID: PMC7689651 DOI: 10.1016/j.bbamcr.2020.118896] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 10/13/2020] [Accepted: 10/14/2020] [Indexed: 12/20/2022]
Abstract
Vitamin B12, cobalamin, is a cobalt-containing ring-contracted modified tetrapyrrole that represents one of the most complex small molecules made by nature. In prokaryotes it is utilised as a cofactor, coenzyme, light sensor and gene regulator yet has a restricted role in assisting only two enzymes within specific eukaryotes including mammals. This deployment disparity is reflected in another unique attribute of vitamin B12 in that its biosynthesis is limited to only certain prokaryotes, with synthesisers pivotal in establishing mutualistic microbial communities. The core component of cobalamin is the corrin macrocycle that acts as the main ligand for the cobalt. Within this review we investigate why cobalt is paired specifically with the corrin ring, how cobalt is inserted during the biosynthetic process, how cobalt is made available within the cell and explore the cellular control of cobalt and cobalamin levels. The partitioning of cobalt for cobalamin biosynthesis exemplifies how cells assist metalation.
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Affiliation(s)
- Deenah Osman
- Department of Biosciences, Durham University, Durham DH1 3LE, UK; Department of Chemistry, Durham University, Durham DH1 3LE, UK.
| | - Anastasia Cooke
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK.
| | - Tessa R Young
- Department of Biosciences, Durham University, Durham DH1 3LE, UK; Department of Chemistry, Durham University, Durham DH1 3LE, UK.
| | - Evelyne Deery
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK.
| | - Nigel J Robinson
- Department of Biosciences, Durham University, Durham DH1 3LE, UK; Department of Chemistry, Durham University, Durham DH1 3LE, UK.
| | - Martin J Warren
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK; Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK; Biomedical Research Centre, University of East Anglia, Norwich NR4 7TJ, UK.
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Electrophysiology Measurements of Metal Transport by MntH2 from Enterococcus faecalis. MEMBRANES 2020; 10:membranes10100255. [PMID: 32987882 PMCID: PMC7599946 DOI: 10.3390/membranes10100255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/16/2020] [Accepted: 09/22/2020] [Indexed: 12/30/2022]
Abstract
Transition metals are essential trace elements and their high-affinity uptake is required for many organisms. Metal transporters are often characterised using metal-sensitive fluorescent dyes, limiting the metals and experimental conditions that can be studied. Here, we have tested whether metal transport by Enterococcus faecalis MntH2 can be measured with an electrophysiology method that is based on the solid-supported membrane technology. E. faecalis MntH2 belongs to the Natural Resistance-Associated Macrophage Protein (Nramp) family of proton-coupled transporters, which transport divalent transition metals and do not transport the earth metals. Electrophysiology confirms transport of Mn(II), Co(II), Zn(II) and Cd(II) by MntH2. However, no uptake responses for Cu(II), Fe(II) and Ni(II) were observed, while the presence of these metals abolishes the uptake signals for Mn(II). Fluorescence assays confirm that Ni(II) is transported. The data are discussed with respect to properties and structures of Nramp-type family members and the ability of electrophysiology to measure charge transport and not directly substrate transport.
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Bioinformatics and Transcriptional Study of the Nramp Gene in the Extreme Acidophile Acidithiobacillus ferrooxidans Strain DC. MINERALS 2020. [DOI: 10.3390/min10060544] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The family of Nramp (natural resistance-associated macrophage protein) metal ion transporter functions in diverse organisms from bacteria to humans. Acidithiobacillus ferrooxidans (At. ferrooxidans) is a Gram-negative bacterium that lives at pH 2 in high concentrations of soluble ferrous ion (600 mM). The AFE_2126 protein of At. ferrooxidans of the Dachang Copper Mine (DC) was analyzed by bioinformatics software or online tools, showing that it was highly homologous to the Nramp family, and its subcellular localization was predicted to locate in the cytoplasmic membrane. Transcriptional study revealed that AFE_2126 was expressed by Fe2+-limiting conditions in At. ferrooxidans DC. It can be concluded that the AFE_2126 protein may function in ferrous ion transport into the cells. Based on the ΔpH of the cytoplasmic membrane between the periplasm (pH 3.5) and the cytoplasm (pH 6.5), it can be concluded that Fe2+ is transported in the direction identical to that of the H+ gradient. This study indirectly confirmed that the function of Nramp in At. ferrooxidans DC can transport divalent iron ions.
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Boles GC, Stevenson BC, Hightower RL, Berden G, Oomens J, Armentrout PB. Zinc and cadmium complexation of L-methionine: An infrared multiple photon dissociation spectroscopy and theoretical study. JOURNAL OF MASS SPECTROMETRY : JMS 2020; 56:e4580. [PMID: 32677757 DOI: 10.1002/jms.4580] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 05/14/2020] [Accepted: 05/20/2020] [Indexed: 06/11/2023]
Abstract
Methionine (Met) cationized with Zn2+ , forming Zn (Met-H)+ (ACN) where ACN = acetonitrile, Zn (Met-H)+ , and ZnCl+ (Met), as well as Cd2+ , forming CdCl+ (Met), were examined by infrared multiple photon dissociation (IRMPD) action spectroscopy using light generated from the FELIX free electron laser. A series of low-energy conformers for each complex was found using quantum-chemical calculations in order to identify the structures formed experimentally. For all four complexes, spectral comparison indicated that the main binding motif observed is a charge solvated, tridentate structure where the metal center binds to the backbone amino group nitrogen, backbone carbonyl oxygen (where the carboxylic acid is deprotonated in two of the Zn2+ complexes), and side-chain sulfur. For all species, the predicted ground structures reproduce the experimental spectra well, although low-lying conformers characterized by similar binding motifs may also contribute in each system. The current work provides valuable information regarding the binding interaction between Met and biologically relevant metals. Further, the comparison between the current work and previous analyses involving alkali metal cationized Met as well as cysteine (the other sulfur containing amino acid) cationized with Zn2+ and Cd2+ allows for the elucidation of important metal dependent trends associated with physiologically important metal-sulfur binding.
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Affiliation(s)
- Georgia C Boles
- Department of Chemistry, University of Utah, Salt Lake City, Utah, USA
| | | | - Randy L Hightower
- Department of Chemistry, University of Utah, Salt Lake City, Utah, USA
| | - Giel Berden
- FELIX Laboratory, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands
| | - Jos Oomens
- FELIX Laboratory, Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - P B Armentrout
- Department of Chemistry, University of Utah, Salt Lake City, Utah, USA
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Martin LM, Konermann L. Enhancing Protein Electrospray Charge States by Multivalent Metal Ions: Mechanistic Insights from MD Simulations and Mass Spectrometry Experiments. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2020; 31:25-33. [PMID: 32881517 DOI: 10.1021/jasms.9b00027] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The structure and reactivity of electrosprayed protein ions is governed by their net charge. Native proteins in non-denaturing aqueous solutions produce low charge states. More highly charged ions are formed when electrospraying proteins that are unfolded and/or exposed to organic supercharging agents. Numerous studies have explored the electrospray process under these various conditions. One phenomenon that has received surprisingly little attention is the charge enhancement caused by multivalent metal ions such as La3+ when electrospraying proteins out of non-denaturing solutions. Here, we conducted mass spectrometry and ion mobility spectrometry experiments, in combination with molecular dynamics (MD) simulations, to uncover the mechanistic basis of this charge enhancement. MD simulations of aqueous ESI droplets reproduced the experimental observation that La3+ boosts protein charge states relative to monovalent metals (e.g., Na+). The simulations showed that gaseous proteins were released by solvent evaporation to dryness, consistent with the charged residue model. Metal ion ejection kept the shrinking droplets close to the Rayleigh limit until ∼99% of the solvent had left. For droplets charged with Na+, metal adduction during the final stage of solvent evaporation produced low protein charge states. Droplets containing La3+ showed a very different behavior. The trivalent nature of La3+ favored adduction to the protein at a very early stage, when most of the solvent had not evaporated yet. This irreversible binding via multidentate contacts suppressed La3+ ejection from the vanishing droplets, such that the resulting gaseous proteins carried significantly more charge. Our results illustrate that MD simulations are suitable for uncovering intricate aspects of electrospray mechanisms, paving the way toward an atomistic understanding of mass spectrometry based analytical workflows.
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Affiliation(s)
- Leanne M Martin
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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Zhang W, Yue S, Song J, Xun M, Han M, Yang H. MhNRAMP1 From Malus hupehensis Exacerbates Cell Death by Accelerating Cd Uptake in Tobacco and Apple Calli. FRONTIERS IN PLANT SCIENCE 2020; 11:957. [PMID: 32733509 PMCID: PMC7358555 DOI: 10.3389/fpls.2020.00957] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 06/10/2020] [Indexed: 05/14/2023]
Abstract
Excessive cadmium (Cd) damages plants by causing cell death. The present study discusses the function of natural resistance-associated macrophage protein (NRAMP) on cell death caused by Cd in Malus hupehensis. MhNRAMP1 was isolated from M. hupehensis roots, and its protein was located in the cell membrane as a transmembrane protein characterized by hydrophobicity. MhNRAMP1 expression in the roots was induced by Cd stress and calcium (Ca) deficiency. MhNRAMP1 overexpression increased Cd concentration in yeasts and enhanced their sensitivity to Cd. Phenotypic comparisons of plants under Cd stress revealed that the growth of transgenic tobacco and apple calli overexpressing MhNRAMP1 was worse than that of the wild type (WT). The Cd2+ influx of transgenic tobacco roots and apple calli was higher, and the recovery time of the Cd2+ influx to a stable state in transgenic apple calli was longer than that of the WT. Cd accumulation and the percentage of apoptotic cells in transgenic lines were higher. Correspondingly, the caspase-1-like and vacuolar processing enzyme (VPE) activities and MdVPEγ expression were higher in transgenic apple calli, but the expression levels of genes that inhibit cell death were lower than those in the WT under Cd stress. Moreover, the Cd translocation from the roots to leaves was increased after MhNRAMP1 overexpression, but the Cd translocation from the leaves to seeds was not affected. These results suggest that MhNRMAP1 exacerbated Cd-induced cell death, which was accomplished by mediating Cd2+ uptake and accumulation, as well as stimulating VPE.
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Affiliation(s)
- Weiwei Zhang
- *Correspondence: Weiwei Zhang, ; Hongqiang Yang,
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Bozzi AT, McCabe AL, Barnett BC, Gaudet R. Transmembrane helix 6b links proton and metal release pathways and drives conformational change in an Nramp-family transition metal transporter. J Biol Chem 2020. [DOI: 10.1016/s0021-9258(17)49881-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Bozzi AT, McCabe AL, Barnett BC, Gaudet R. Transmembrane helix 6b links proton and metal release pathways and drives conformational change in an Nramp-family transition metal transporter. J Biol Chem 2019; 295:1212-1224. [PMID: 31882536 DOI: 10.1074/jbc.ra119.011336] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 12/10/2019] [Indexed: 12/15/2022] Open
Abstract
The natural resistance-associated macrophage protein (Nramp) family encompasses transition metal and proton cotransporters that are present in many organisms from bacteria to humans. Recent structures of Deinococcus radiodurans Nramp (DraNramp) in multiple conformations revealed the intramolecular rearrangements required for alternating access of the metal-binding site to the external or cytosolic environment. Here, using recombinant proteins and metal transport and cysteine accessibility assays, we demonstrate that two parallel cytoplasm-accessible networks of conserved hydrophilic residues in DraNramp, one lining the wide intracellular vestibule for metal release and the other forming a narrow proton transport pathway, are essential for metal transport. We further show that mutagenic or posttranslational modifications of transmembrane helix (TM) 6b, which structurally links these two pathways, impede normal conformational cycling and metal transport. TM6b contains two highly conserved histidines, His232 and His237 We found that different mutagenic perturbations of His232, just below the metal-binding site along the proton exit route, differentially affect DraNramp's conformational state, suggesting that His232 serves as a pivot point for conformational changes. In contrast, any replacement of His237, lining the metal exit route, locked the transporter in a transport-inactive outward-closed state. We conclude that these two histidines, and TM6b more broadly, help trigger the bulk rearrangement of DraNramp to the inward-open state upon metal binding and facilitate return of the empty transporter to an outward-open state upon metal release.
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Affiliation(s)
- Aaron T Bozzi
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138
| | - Anne L McCabe
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138
| | - Benjamin C Barnett
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138
| | - Rachelle Gaudet
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138
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Manatschal C, Pujol-Giménez J, Poirier M, Reymond JL, Hediger MA, Dutzler R. Mechanistic basis of the inhibition of SLC11/NRAMP-mediated metal ion transport by bis-isothiourea substituted compounds. eLife 2019; 8:51913. [PMID: 31804182 PMCID: PMC6917499 DOI: 10.7554/elife.51913] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 11/22/2019] [Indexed: 12/23/2022] Open
Abstract
In humans, the divalent metal ion transporter-1 (DMT1) mediates the transport of ferrous iron across the apical membrane of enterocytes. Hence, its inhibition could be beneficial for the treatment of iron overload disorders. Here we characterize the interaction of aromatic bis-isothiourea-substituted compounds with human DMT1 and its prokaryotic homologue EcoDMT. Both transporters are inhibited by a common competitive mechanism with potencies in the low micromolar range. The crystal structure of EcoDMT in complex with a brominated derivative defines the binding of the inhibitor to an extracellular pocket of the transporter in direct contact with residues of the metal ion coordination site, thereby interfering with substrate loading and locking the transporter in its outward-facing state. Mutagenesis and structure-activity relationships further support the observed interaction mode and reveal species-dependent differences between pro- and eukaryotic transporters. Together, our data provide the first detailed mechanistic insight into the pharmacology of SLC11/NRAMP transporters.
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Affiliation(s)
| | - Jonai Pujol-Giménez
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland.,Membrane Transport Discovery Lab, Department of Nephrology and Hypertension, Inselspital, University of Bern, Bern, Switzerland.,Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Marion Poirier
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Jean-Louis Reymond
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Matthias A Hediger
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland.,Membrane Transport Discovery Lab, Department of Nephrology and Hypertension, Inselspital, University of Bern, Bern, Switzerland.,Department of Biomedical Research, University of Bern, Bern, Switzerland
| | - Raimund Dutzler
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
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Bozzi AT, Bane LB, Zimanyi CM, Gaudet R. Unique structural features in an Nramp metal transporter impart substrate-specific proton cotransport and a kinetic bias to favor import. J Gen Physiol 2019; 151:1413-1429. [PMID: 31619456 PMCID: PMC6888756 DOI: 10.1085/jgp.201912428] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 09/26/2019] [Indexed: 01/01/2023] Open
Abstract
Natural resistance-associated macrophage protein (Nramp) transporters enable uptake of essential transition metal micronutrients in numerous biological contexts. These proteins are believed to function as secondary transporters that harness the electrochemical energy of proton gradients by "coupling" proton and metal transport. Here we use the Deinococcus radiodurans (Dra) Nramp homologue, for which we have determined crystal structures in multiple conformations, to investigate mechanistic details of metal and proton transport. We untangle the proton-metal coupling behavior of DraNramp into two distinct phenomena: ΔpH stimulation of metal transport rates and metal stimulation of proton transport. Surprisingly, metal type influences substrate stoichiometry, leading to manganese-proton cotransport but cadmium uniport, while proton uniport also occurs. Additionally, a physiological negative membrane potential is required for high-affinity metal uptake. To begin to understand how Nramp's structure imparts these properties, we target a conserved salt-bridge network that forms a proton-transport pathway from the metal-binding site to the cytosol. Mutations to this network diminish voltage and ΔpH dependence of metal transport rates, alter substrate selectivity, perturb or eliminate metal-stimulated proton transport, and erode the directional bias favoring outward-to-inward metal transport under physiological-like conditions. Thus, this unique salt-bridge network may help Nramp-family transporters maximize metal uptake and reduce deleterious back-transport of acquired metals. We provide a new mechanistic model for Nramp proton-metal cotransport and propose that functional advantages may arise from deviations from the traditional model of symport.
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Affiliation(s)
- Aaron T Bozzi
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA
| | - Lukas B Bane
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA
| | - Christina M Zimanyi
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA
| | - Rachelle Gaudet
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA
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Cunrath O, Bumann D. Host resistance factor SLC11A1 restrictsSalmonellagrowth through magnesium deprivation. Science 2019; 366:995-999. [DOI: 10.1126/science.aax7898] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 08/12/2019] [Accepted: 10/25/2019] [Indexed: 12/30/2022]
Abstract
The pleiotropic host resistance factor SLC11A1 (NRAMP1) defends against diverse intracellular pathogens in mammals by yet-unknown mechanisms. We comparedSalmonellainfection of coisogenic mice with differentSLC11A1alleles. SLC11A1 reducedSalmonellareplication and triggered up-regulation of uptake systems for divalent metal cations but no other stress responses. SLC11A1 modestly diminished iron availability and acutely restrictedSalmonellaaccess to magnesium. Growth ofSalmonellacells in the presence of SLC11A1 was highly heterogeneous and inversely correlated with expression of the crucial magnesium transporter genemgtB. We observed superimposable single-cell patterns in mice lacking SLC11A1 when we restrictedSalmonellaaccess to magnesium by impairing its uptake. Together, these findings identify deprivation of the main group metal magnesium as the main resistance mechanism of SLC11A1 againstSalmonella.
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Designing yeast as plant-like hyperaccumulators for heavy metals. Nat Commun 2019; 10:5080. [PMID: 31704944 PMCID: PMC6841955 DOI: 10.1038/s41467-019-13093-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 10/14/2019] [Indexed: 02/01/2023] Open
Abstract
Hyperaccumulators typically refer to plants that absorb and tolerate elevated amounts of heavy metals. Due to their unique metal trafficking abilities, hyperaccumulators are promising candidates for bioremediation applications. However, compared to bacteria-based bioremediation systems, plant life cycle is long and growing conditions are difficult to maintain hindering their adoption. Herein, we combine the robust growth and engineerability of bacteria with the unique waste management mechanisms of plants by using a more tractable platform-the common baker’s yeast-to create plant-like hyperaccumulators. Through overexpression of metal transporters and engineering metal trafficking pathways, engineered yeast strains are able to sequester metals at concentrations 10–100 times more than established hyperaccumulator thresholds for chromium, arsenic, and cadmium. Strains are further engineered to be selective for either cadmium or strontium removal, specifically for radioactive Sr90. Overall, this work presents a systematic approach for transforming yeast into metal hyperaccumulators that are as effective as their plant counterparts. Existing heavy metal bioremediation systems are mainly based on plants, which require long growing time in specific conditions. Here, the authors mimic the characteristics of plant hyperaccumulators to engineer more tractable baker’s yeast and achieve 10–100-fold higher accumulation of chromium, arsenic, or cadmium.
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Nuryady MM, Widayanti R, Nurcahyo RW, Fadjrinatha B, Fahrurrozi Z S A. Characterization and phylogenetic analysis of multidrug-resistant protein - encoding genes in Trypanosoma evansi isolated from buffaloes in Ngawi district, Indonesia. Vet World 2019; 12:1573-1577. [PMID: 31849418 PMCID: PMC6868250 DOI: 10.14202/vetworld.2019.1573-1577] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 09/03/2019] [Indexed: 11/16/2022] Open
Abstract
Background and Aim: Excessive use of trypanocidal drugs can lead to cases of drug resistance. Multiple cases of resistance have been widely reported for drugs such as isometamidium chloride and diminazene aceturate. These cases deserve serious attention, especially in Indonesia, where the first case was recorded and where the molecular basis of trypanocidal drug resistance has never been evaluated. This study aimed to analyze the multidrug resistance protein (MRP) gene in Trypanosoma evansi isolates, sampled from Indonesia, by focusing on the phylogenetic relationship between these isolates and other Trypanosoma spp. Materials and Methods: A total of 88 blood samples were drawn from buffaloes in the Ngawi district, Indonesia. Animals infected with T. evansi were detected through the microhematocrit technique and Giemsa blood smear methods. Positive blood samples were used to inoculate in male mice (Mus musculus BALB-C strain) as an animal model for culturing the T. evansi. The genomic DNA of the blood taken from the T. evansi- infected mice was used for polymerase chain reaction amplification, sequencing, and phylogenetic analysis. Results: Two genes were analyzed; the first gene detected for T. evansi corresponded to Trypanosomabrucei with a homology of 99% and the second gene to Trypanosoma brucei gambiense, with a homology of 100%. These two genes of the MRP from T. evansi showed clear similarity to the MRPE and MRPA genes of the T. brucei ssp. Conclusion: The MRP gene is conserved on the subspecies level of T. brucei. Only few point mutations were found between various sequences, which mean that the proteins have the same structure. This is important to treat the parasite with the appropriate drugs in the future.
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Affiliation(s)
- Mohammad Mirza Nuryady
- Department of Biology Education, Faculty of Teacher Training and Education, Universitas Muhammadiyah Malang, Malang, Indonesia
| | - Rini Widayanti
- Department of Biochemistry, Veterinary Medicine Faculty, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Raden Wisnu Nurcahyo
- Department of Parasitology, Veterinary Medicine Faculty, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Brilyantika Fadjrinatha
- Department of Parasitology, Veterinary Medicine Faculty, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Ahmad Fahrurrozi Z S
- Department of Tropical Medicine, Medicine Faculty, Universitas Gadjah Mada, Yogyakarta, Indonesia
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Christenson ET, Isaac DT, Yoshida K, Lipo E, Kim JS, Ghirlando R, Isberg RR, Banerjee A. The iron-regulated vacuolar Legionella pneumophila MavN protein is a transition-metal transporter. Proc Natl Acad Sci U S A 2019; 116:17775-17785. [PMID: 31431530 PMCID: PMC6731752 DOI: 10.1073/pnas.1902806116] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Legionella pneumophila causes a potentially fatal form of pneumonia by replicating within macrophages in the Legionella-containing vacuole (LCV). Bacterial survival and proliferation within the LCV rely on hundreds of secreted effector proteins comprising high functional redundancy. The vacuolar membrane-localized MavN, hypothesized to support iron transport, is unique among effectors because loss-of-function mutations result in severe intracellular growth defects. We show here an iron starvation response by L. pneumophila after infection of macrophages that was prematurely induced in the absence of MavN, consistent with MavN granting access to limiting cellular iron stores. MavN cysteine accessibilities to a membrane-impermeant label were determined during macrophage infections, revealing a topological pattern supporting multipass membrane transporter models. Mutations to several highly conserved residues that can take part in metal recognition and transport resulted in defective intracellular growth. Purified MavN and mutant derivatives were directly tested for transporter activity after heterologous purification and liposome reconstitution. Proteoliposomes harboring MavN exhibited robust transport of Fe2+, with the severity of defect of most mutants closely mimicking the magnitude of defects during intracellular growth. Surprisingly, MavN was equivalently proficient at transporting Fe2+, Mn2+, Co2+, or Zn2+ Consequently, flooding infected cells with either Mn2+ or Zn2+ allowed collaboration with iron to enhance intracellular growth of L. pneumophila ΔmavN strains, indicating a clear role for MavN in transporting each of these ions. These findings reveal that MavN is a transition-metal-ion transporter that plays a critical role in response to iron limitation during Legionella infection.
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Affiliation(s)
- Eric T Christenson
- Unit on Structural and Chemical Biology of Membrane Proteins, Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
| | - Dervla T Isaac
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111
| | - Karin Yoshida
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111
| | - Erion Lipo
- Program in Genetics, Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111
| | - Jin-Sik Kim
- Unit on Structural and Chemical Biology of Membrane Proteins, Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
| | - Rodolfo Ghirlando
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Ralph R Isberg
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111;
| | - Anirban Banerjee
- Unit on Structural and Chemical Biology of Membrane Proteins, Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892;
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Kato T, Kumazaki K, Wada M, Taniguchi R, Nakane T, Yamashita K, Hirata K, Ishitani R, Ito K, Nishizawa T, Nureki O. Crystal structure of plant vacuolar iron transporter VIT1. NATURE PLANTS 2019; 5:308-315. [PMID: 30742036 DOI: 10.1038/s41477-019-0367-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Accepted: 01/11/2019] [Indexed: 06/09/2023]
Abstract
The iron ion is an essential cofactor in several vital enzymatic reactions, such as DNA replication, oxygen transport, and respiratory and photosynthetic electron transfer chains, but its excess accumulation induces oxidative stress in cells. Vacuolar iron transporter 1 (VIT1) is important for iron homeostasis in plants, by transporting cytoplasmic ferrous ions into vacuoles. Modification of the VIT1 gene leads to increased iron content in crops, which could be used for the treatment of human iron deficiency diseases. Furthermore, a VIT1 from the malaria-causing parasite Plasmodium is considered as a potential drug target for malaria. Here we report the crystal structure of VIT1 from rose gum Eucalyptus grandis, which probably functions as a H+-dependent antiporter for Fe2+ and other transition metal ions. VIT1 adopts a novel protein fold forming a dimer of five membrane-spanning domains, with an ion-translocating pathway constituted by the conserved methionine and carboxylate residues at the dimer interface. The second transmembrane helix protrudes from the lipid membrane by about 40 Å and connects to a three-helical bundle, triangular cytoplasmic domain, which binds to the substrate metal ions and stabilizes their soluble form, thus playing an essential role in their transport. These mechanistic insights will provide useful information for the further design of genetically modified crops and the development of anti-malaria drugs.
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Affiliation(s)
- Takafumi Kato
- Department of Biological Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Kaoru Kumazaki
- Department of Biological Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Miki Wada
- Department of computational biology and medical sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Reiya Taniguchi
- Department of Biological Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Takanori Nakane
- Department of Biological Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Structural Studies Division, MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | | | - Kunio Hirata
- RIKEN SPring-8 Center, Sayo, Japan
- Precursory Research for Embryonic Science and Technology , Japan Science and Technology Agency, Kawaguchi, Japan
| | - Ryuichiro Ishitani
- Department of Biological Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Koichi Ito
- Department of computational biology and medical sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Tomohiro Nishizawa
- Department of Biological Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
- Precursory Research for Embryonic Science and Technology , Japan Science and Technology Agency, Kawaguchi, Japan.
| | - Osamu Nureki
- Department of Biological Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
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Bozzi AT, Zimanyi CM, Nicoludis JM, Lee BK, Zhang CH, Gaudet R. Structures in multiple conformations reveal distinct transition metal and proton pathways in an Nramp transporter. eLife 2019; 8:41124. [PMID: 30714568 PMCID: PMC6398981 DOI: 10.7554/elife.41124] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 01/31/2019] [Indexed: 01/03/2023] Open
Abstract
Nramp family transporters—expressed in organisms from bacteria to humans—enable uptake of essential divalent transition metals via an alternating-access mechanism that also involves proton transport. We present high-resolution structures of Deinococcus radiodurans (Dra)Nramp in multiple conformations to provide a thorough description of the Nramp transport cycle by identifying the key intramolecular rearrangements and changes to the metal coordination sphere. Strikingly, while metal transport requires cycling from outward- to inward-open states, efficient proton transport still occurs in outward-locked (but not inward-locked) DraNramp. We propose a model in which metal and proton enter the transporter via the same external pathway to the binding site, but follow separate routes to the cytoplasm, which could facilitate the co-transport of two cationic species. Our results illustrate the flexibility of the LeuT fold to support a broad range of substrate transport and conformational change mechanisms. Cells use transport proteins embedded in their membrane to acquire many of the nutrients they need to survive and grow. Different transport proteins transport different nutrients; for example, the Nramp transporters move transition metal ions across cell membranes. Nramps are found in a wide range of organisms. Bacteria use them to acquire the metals they need during the course of an infection, and humans rely on Nramps to absorb iron from food. Nramps can also transport hydrogen ions (known as protons). Understanding how the structure of an Nramp transporter changes as it transports metal ions and protons can help researchers to understand how it works. These structures can be studied using a technique called X-ray crystallography, which captures snapshots of the proteins at different stages of their task. Bozzi, Zimanyi et al. used X-ray crystallography to study the structures of an Nramp transporter from the bacterium Deinococcus radiodurans. The results reveal four of the shapes that the Nramp transporter takes on at different stages in its transport process, including the first structure to show an Nramp binding to a metal ion from the outside of the cell. Taken together, the structures suggest a new transport mechanism that has not been seen in previously studied transport proteins with similar structures. An unexpected feature of this mechanism is that Nramps transport metal ions and protons along different pathways. Studying the transport mechanisms used by Nramp transporters will help researchers to understand how cells maintain appropriate levels of metal ions, an important component of human health. The mechanisms of relatively few transport proteins are understood at a structural level, yet many share common origins and have shared characteristics. Understanding how Nramps work could therefore help us to understand how wider classes of transporters work as well.
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Affiliation(s)
- Aaron T Bozzi
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States
| | - Christina M Zimanyi
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States
| | - John M Nicoludis
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States
| | - Brandon K Lee
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States
| | - Casey H Zhang
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States
| | - Rachelle Gaudet
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States
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49
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Triantaphyllopoulos KA, Baltoumas FA, Hamodrakas SJ. Structural characterization and molecular dynamics simulations of the caprine and bovine solute carrier family 11 A1 (SLC11A1). J Comput Aided Mol Des 2018; 33:265-285. [PMID: 30543052 DOI: 10.1007/s10822-018-0179-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 12/03/2018] [Indexed: 12/22/2022]
Abstract
Natural Resistance-Associated Macrophage Proteins are a family of transmembrane divalent metal ion transporters, with important implications in life of both bacteria and mammals. Among them, the Solute Carrier family 11 member A1 (SLC11A1) has been implicated with susceptibility to infection by Mycobacterium avium subspecies paratuberculosis (MAP), potentially causing Crohn's disease in humans and paratuberculosis (PTB) in ruminants. Our previous research had focused on sequencing the mRNA of the caprine slc11a1 gene and pinpointed polymorphisms that contribute to caprine SLC11A1's susceptibility to infection by MAP in PTB. Despite its importance, little is known on the structural/dynamic features of mammalian SLC11A1 that may influence its function under normal or pathological conditions at the protein level. In this work we studied the structural architecture of SLC11A1 in Capra hircus and Bos taurus through molecular modeling, molecular dynamics simulations in different, functionally relevant configurations, free energy calculations of protein-metal interactions and sequence conservation analysis. The results of this study propose a three dimensional structure for SLC11A1 with conserved sequence and structural features and provide hints for a potential mechanism through which divalent metal ion transport is conducted. Given the importance of SLC11A1 in susceptibility to PTB, this study provides a framework for further studies on the structure and dynamics of SLC11A1 in other organisms, to gain 3D structural insight into the macromolecular arrangements of SLC11A1 but also suggesting a potential mechanism which divalent metal ion transport is conducted.
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Affiliation(s)
- Kostas A Triantaphyllopoulos
- Department of Animal Breeding and Husbandry, Faculty of Animal Science and Aquaculture, School of Agricultural Production, Infrastructure and Environment, Agricultural University of Athens, 75 Iera Odos St., 11855, Athens, Greece.
| | - Fotis A Baltoumas
- Section of Cell Biology and Biophysics, Department of Biology, School of Sciences, National and Kapodistrian University of Athens, Panepistimiopolis, 15701, Athens, Greece
| | - Stavros J Hamodrakas
- Section of Cell Biology and Biophysics, Department of Biology, School of Sciences, National and Kapodistrian University of Athens, Panepistimiopolis, 15701, Athens, Greece
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50
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Ullah I, Wang Y, Eide DJ, Dunwell JM. Evolution, and functional analysis of Natural Resistance-Associated Macrophage Proteins (NRAMPs) from Theobroma cacao and their role in cadmium accumulation. Sci Rep 2018; 8:14412. [PMID: 30258092 PMCID: PMC6158261 DOI: 10.1038/s41598-018-32819-y] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 09/13/2018] [Indexed: 12/22/2022] Open
Abstract
The presence of the toxic metal cadmium (Cd2+) in certain foodstuffs is recognised as a global problem, and there is increasing legislative pressure to reduce the content of Cd in food. The present study was conducted on cacao (Theobroma cacao), the source of chocolate, and one of the crops known to accumulate Cd in certain conditions. There are a range of possible genetic and agronomic methods being tested as a route to such reduction. As part of a gene-based approach, we focused on the Natural Resistance-Associated Macrophage Proteins (NRAMPS), a family of proton/metal transporter proteins that are evolutionarily conserved across all species from bacteria to humans. The plant NRAMP gene family are of particular importance as they are responsible for uptake of the nutritionally vital divalent cations Fe2+, Mn2+, Zn2+, as well as Cd2+. We identified the five NRAMP genes in cacao, sequenced these genes and studied their expression in various organs. We then confirmed the expression patterns in response to variation in nutrient cation availability and addition of Cd2+. Functional analysis by expression in yeast provided evidence that NRAMP5 encoded a protein capable of Cd2+ transport, and suggested this gene as a target for genetic selection/modification.
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Affiliation(s)
- Ihsan Ullah
- School of Agriculture, Policy and Development, University of Reading, Earley Gate, Reading, RG6 6AR, UK
| | - Yirong Wang
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - David J Eide
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Jim M Dunwell
- School of Agriculture, Policy and Development, University of Reading, Earley Gate, Reading, RG6 6AR, UK.
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