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Narozhnykh KN, Petukhov VL, Syso AI, Konovalova TV, Korotkevich OS, Sebezhko OI. Specific of accumulation of manganese in organs and tissues of Hereford cattle. BRAZ J BIOL 2024; 84:e282174. [PMID: 38836803 DOI: 10.1590/1519-6984.282174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 03/26/2024] [Indexed: 06/06/2024] Open
Abstract
The elemental status of cattle is one of the important factors, which determine its growth, fertility, fetal development, meat and dairy production, etc. Therefore, the study of content of different elements in cattle organs and tissues and its correlation with cattle characteristics and diet is urgent task. It is also important to develop intravital and low-invasive methods to analyze element content in cattle to regulate its diet during lifetime. In the present work, we have studied the content and distribution of manganese in Hereford cattle from an ecologically clean zone of Western Siberia (Russia). 252 samples were taken from 31 bulls aged 15-18 months. They were collected from various livestock farms in the region and analyzed using atomic absorption spectrophotometry (organs and muscle tissue) and inductively coupled plasma atomic emission spectrometry (hair). The median values of manganese concentration obtained in natural moisture for hair, heart, kidneys, liver, lungs, muscles, spleen, testes, and brain were 25, 0.37, 1.0, 2.6, 0.4, 0.2, 0.4, 0.5, and 0.5 ppm. Accordingly, the concentration of manganese differs significantly in the organs and tissues of animals (H = 188.6, df = 8, p <0.0001). Statistically significant associations of manganese were revealed in pairs: liver-testis, hair-testis, spleen-testis, and heart-brain. The classification of organs and tissues of animals according to the level of content and variability of manganese is carried out. The concentration of manganese in the body is not uniform, most of all it is deposited in the hair and excretory organs of the liver and kidneys. In other organs and muscle tissues, the distribution of manganese is more even and is in the range of 0.2-0.5 ppm. The resulting ranges can be used as a guideline for Hereford cattle bred in Western Siberia.
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Affiliation(s)
- K N Narozhnykh
- Federal State Budgetary Educational Institution of Higher Education "Novosibirsk State Agrarian University", Novosibirsk, Russia
| | - V L Petukhov
- Federal State Budgetary Educational Institution of Higher Education "Novosibirsk State Agrarian University", Novosibirsk, Russia
| | - A I Syso
- Institute of Soil Science and Agrochemistry of the Siberian Branch of the RAS, Novosibirsk, Russia
| | - T V Konovalova
- Federal State Budgetary Educational Institution of Higher Education "Novosibirsk State Agrarian University", Novosibirsk, Russia
| | - O S Korotkevich
- Federal State Budgetary Educational Institution of Higher Education "Novosibirsk State Agrarian University", Novosibirsk, Russia
| | - O I Sebezhko
- Federal State Budgetary Educational Institution of Higher Education "Novosibirsk State Agrarian University", Novosibirsk, Russia
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2
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Chereddy SCRR, Makino T. Conserved Genes in Highly Regenerative Metazoans Are Associated with Planarian Regeneration. Genome Biol Evol 2024; 16:evae082. [PMID: 38652806 PMCID: PMC11077316 DOI: 10.1093/gbe/evae082] [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: 01/10/2024] [Revised: 04/10/2024] [Accepted: 04/16/2024] [Indexed: 04/25/2024] Open
Abstract
Metazoan species depict a wide spectrum of regeneration ability which calls into question the evolutionary origins of the underlying processes. Since species with high regeneration ability are widely distributed throughout metazoans, there is a possibility that the metazoan ancestor had an underlying common molecular mechanism. Early metazoans like sponges possess high regenerative ability, but, due to the large differences they have with Cnidaria and Bilateria regarding symmetry and neuronal systems, it can be inferred that this regenerative ability is different. We hypothesized that the last common ancestor of Cnidaria and Bilateria possessed remarkable regenerative ability which was lost during evolution. We separated Cnidaria and Bilateria into three classes possessing whole-body regenerating, high regenerative ability, and low regenerative ability. Using a multiway BLAST and gene phylogeny approach, we identified genes conserved in whole-body regenerating species and lost in low regenerative ability species and labeled them Cnidaria and Bilaterian regeneration genes. Through transcription factor analysis, we identified that Cnidaria and Bilaterian regeneration genes were associated with an overabundance of homeodomain regulatory elements. RNA interference of Cnidaria and Bilaterian regeneration genes resulted in loss of regeneration phenotype for HRJDa, HRJDb, DUF21, DISP3, and ARMR genes. We observed that DUF21 knockdown was highly lethal in the early stages of regeneration indicating a potential role in wound response. Also, HRJDa, HRJDb, DISP3, and ARMR knockdown showed loss of regeneration phenotype after second amputation. The results strongly correlate with their respective RNA-seq profiles. We propose that Cnidaria and Bilaterian regeneration genes play a major role in regeneration across highly regenerative Cnidaria and Bilateria.
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Affiliation(s)
| | - Takashi Makino
- Graduate School of Life Sciences, Tohoku University, Sendai 980-8578, Japan
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3
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Qiu C, Arora P, Malik I, Laperuta AJ, Pavlovic EM, Ugochukwu S, Naik M, Kaplan CD. Thiolutin has complex effects in vivo but is a direct inhibitor of RNA polymerase II in vitro. Nucleic Acids Res 2024; 52:2546-2564. [PMID: 38214235 PMCID: PMC10954460 DOI: 10.1093/nar/gkad1258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 12/18/2023] [Accepted: 12/29/2023] [Indexed: 01/13/2024] Open
Abstract
Thiolutin is a natural product transcription inhibitor with an unresolved mode of action. Thiolutin and the related dithiolopyrrolone holomycin chelate Zn2+ and previous studies have concluded that RNA Polymerase II (Pol II) inhibition in vivo is indirect. Here, we present chemicogenetic and biochemical approaches to investigate thiolutin's mode of action in Saccharomyces cerevisiae. We identify mutants that alter sensitivity to thiolutin. We provide genetic evidence that thiolutin causes oxidation of thioredoxins in vivo and that thiolutin both induces oxidative stress and interacts functionally with multiple metals including Mn2+ and Cu2+, and not just Zn2+. Finally, we show direct inhibition of RNA polymerase II (Pol II) transcription initiation by thiolutin in vitro in support of classical studies that thiolutin can directly inhibit transcription in vitro. Inhibition requires both Mn2+ and appropriate reduction of thiolutin as excess DTT abrogates its effects. Pause prone, defective elongation can be observed in vitro if inhibition is bypassed. Thiolutin effects on Pol II occupancy in vivo are widespread but major effects are consistent with prior observations for Tor pathway inhibition and stress induction, suggesting that thiolutin use in vivo should be restricted to studies on its modes of action and not as an experimental tool.
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Affiliation(s)
- Chenxi Qiu
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Payal Arora
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Indranil Malik
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | | | | | | | - Mandar Naik
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Craig D Kaplan
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
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4
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Chen YS, Gehring K. New insights into the structure and function of CNNM proteins. FEBS J 2023; 290:5475-5495. [PMID: 37222397 DOI: 10.1111/febs.16872] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/17/2023] [Accepted: 05/23/2023] [Indexed: 05/25/2023]
Abstract
Magnesium (Mg2+ ) is the most abundant divalent cation in cells and plays key roles in almost all biological processes. CBS-pair domain divalent metal cation transport mediators (CNNMs) are a newly characterized class of Mg2+ transporters present throughout biology. Originally discovered in bacteria, there are four CNNM proteins in humans, which are involved in divalent cation transport, genetic diseases, and cancer. Eukaryotic CNNMs are composed of four domains: an extracellular domain, a transmembrane domain, a cystathionine-β-synthase (CBS)-pair domain, and a cyclic nucleotide-binding homology domain. The transmembrane and CBS-pair core are the defining features of CNNM proteins with over 20 000 protein sequences known from over 8000 species. Here, we review the structural and functional studies of eukaryotic and prokaryotic CNNMs that underlie our understanding of their regulation and mechanism of ion transport. Recent structures of prokaryotic CNNMs confirm the transmembrane domain mediates ion transport with the CBS-pair domain likely playing a regulatory role through binding divalent cations. Studies of mammalian CNNMs have identified new binding partners. These advances are driving progress in understanding this deeply conserved and widespread family of ion transporters.
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Affiliation(s)
- Yu Seby Chen
- Department of Biochemistry & Molecular Biology, Life Sciences Institute, The University of British Columbia, Vancouver, BC, Canada
| | - Kalle Gehring
- Department of Biochemistry & Centre de Recherche en Biologie Structurale, McGill University, Montreal, QC, Canada
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5
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Inoue S, Hayashi M, Huang S, Yokosho K, Gotoh E, Ikematsu S, Okumura M, Suzuki T, Kamura T, Kinoshita T, Ma JF. A tonoplast-localized magnesium transporter is crucial for stomatal opening in Arabidopsis under high Mg 2+ conditions. THE NEW PHYTOLOGIST 2022; 236:864-877. [PMID: 35976788 PMCID: PMC9804957 DOI: 10.1111/nph.18410] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
Plant stomata play an important role in CO2 uptake for photosynthesis and transpiration, but the mechanisms underlying stomatal opening and closing under changing environmental conditions are still not completely understood. Through large-scale genetic screening, we isolated an Arabidopsis mutant (closed stomata2 (cst2)) that is defective in stomatal opening. We cloned the causal gene (MGR1/CST2) and functionally characterized this gene. The mutant phenotype was caused by a mutation in a gene encoding an unknown protein with similarities to the human magnesium (Mg2+ ) efflux transporter ACDP/CNNM. MGR1/CST2 was localized to the tonoplast and showed transport activity for Mg2+ . This protein was constitutively and highly expressed in guard cells. Knockout of this gene resulted in stomatal closing, decreased photosynthesis and growth retardation, especially under high Mg2+ conditions, while overexpression of this gene increased stomatal opening and tolerance to high Mg2+ concentrations. Furthermore, guard cell-specific expression of MGR1/CST2 in the mutant partially restored its stomatal opening. Our results indicate that MGR1/CST2 expression in the leaf guard cells plays an important role in maintaining cytosolic Mg2+ concentrations through sequestering Mg2+ into vacuoles, which is required for stomatal opening, especially under high Mg2+ conditions.
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Affiliation(s)
- Shin‐ichiro Inoue
- Division of Biological Science, Graduate School of ScienceNagoya UniversityFuro‐cho, Chikusa‐kuNagoyaAichi464‐8602Japan
| | - Maki Hayashi
- Division of Biological Science, Graduate School of ScienceNagoya UniversityFuro‐cho, Chikusa‐kuNagoyaAichi464‐8602Japan
| | - Sheng Huang
- Institute of Plant Science and ResourcesOkayama UniversityChuo 2‐20‐1Kurashiki710‐0046Japan
| | - Kengo Yokosho
- Institute of Plant Science and ResourcesOkayama UniversityChuo 2‐20‐1Kurashiki710‐0046Japan
| | - Eiji Gotoh
- Department of Forest Environmental Sciences, Faculty of AgricultureKyushu University744 MotookaFukuoka819‐0395Japan
| | - Shuka Ikematsu
- Institute of Transformative Bio‐Molecules (WPI‐ITbM)Nagoya UniversityFuro‐cho, ChikusaNagoya464‐8602Japan
| | - Masaki Okumura
- Division of Biological Science, Graduate School of ScienceNagoya UniversityFuro‐cho, Chikusa‐kuNagoyaAichi464‐8602Japan
| | - Takamasa Suzuki
- Department of Biological Chemistry, College of Bioscience and BiotechnologyChubu UniversityKasugai‐shiAichi487‐8501Japan
| | - Takumi Kamura
- Division of Biological Science, Graduate School of ScienceNagoya UniversityFuro‐cho, Chikusa‐kuNagoyaAichi464‐8602Japan
| | - Toshinori Kinoshita
- Division of Biological Science, Graduate School of ScienceNagoya UniversityFuro‐cho, Chikusa‐kuNagoyaAichi464‐8602Japan
- Institute of Transformative Bio‐Molecules (WPI‐ITbM)Nagoya UniversityFuro‐cho, ChikusaNagoya464‐8602Japan
| | - Jian Feng Ma
- Institute of Plant Science and ResourcesOkayama UniversityChuo 2‐20‐1Kurashiki710‐0046Japan
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Meng SF, Zhang B, Tang RJ, Zheng XJ, Chen R, Liu CG, Jing YP, Ge HM, Zhang C, Chu YL, Fu AG, Zhao FG, Luan S, Lan WZ. Four plasma membrane-localized MGR transporters mediate xylem Mg 2+ loading for root-to-shoot Mg 2+ translocation in Arabidopsis. MOLECULAR PLANT 2022; 15:805-819. [PMID: 35063662 DOI: 10.1016/j.molp.2022.01.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 11/14/2021] [Accepted: 01/16/2022] [Indexed: 06/14/2023]
Abstract
Magnesium (Mg2+), an essential structural component of chlorophyll, is absorbed from the soil by roots and transported to shoots to support photosynthesis in plants. However, the molecular mechanisms underlying root-to-shoot Mg2+ translocation remain largely unknown. We describe here the identification of four plasma membrane (PM)-localized transporters, named Mg2+ release transporters (MGRs), that are critical for root-to-shoot Mg transport in Arabidopsis. Functional complementation assays in a Mg2+-uptake-deficient bacterial strain confirmed that these MGRs conduct Mg2+ transport. PM-localized MGRs (MGR4, MGR5, MGR6, and MGR7) were expressed primarily in root stellar cells and participated in the xylem loading step of the long-distance Mg2+ transport process. In particular, MGR4 and MGR6 played a major role in shoot Mg homeostasis, as their loss-of-function mutants were hypersensitive to low Mg2+ but tolerant to high Mg2+ conditions. Reciprocal grafting analysis further demonstrated that MGR4 functions in the root to determine shoot Mg2+ accumulation and physiological phenotypes caused by both low- and high-Mg2+ stress. Taken together, our study has identified the long-sought transporters responsible for root-to-shoot Mg2+ translocation in plants.
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Affiliation(s)
- Su-Fang Meng
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, Jiangsu, China
| | - Bin Zhang
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, Jiangsu, China; Institute of Future Agriculture, Northwest A&F University, Yangling 712100, Shaanxi, China; The Key Laboratory of Western Resources Biology and Biological Technology, College of Life Sciences, Northwest University, Xi'an 710069, China
| | - Ren-Jie Tang
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Xiao-Jiang Zheng
- The Key Laboratory of Western Resources Biology and Biological Technology, College of Life Sciences, Northwest University, Xi'an 710069, China; Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Rui Chen
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, Jiangsu, China
| | - Cong-Ge Liu
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, Jiangsu, China
| | - Yan-Ping Jing
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, Jiangsu, China; The Key Laboratory of Western Resources Biology and Biological Technology, College of Life Sciences, Northwest University, Xi'an 710069, China
| | - Hai-Man Ge
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, Jiangsu, China
| | - Chi Zhang
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, Jiangsu, China; The Key Laboratory of Western Resources Biology and Biological Technology, College of Life Sciences, Northwest University, Xi'an 710069, China
| | - Yan-Li Chu
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, Jiangsu, China
| | - Ai-Gen Fu
- The Key Laboratory of Western Resources Biology and Biological Technology, College of Life Sciences, Northwest University, Xi'an 710069, China
| | - Fu-Geng Zhao
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, Jiangsu, China
| | - Sheng Luan
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA.
| | - Wen-Zhi Lan
- State Key Laboratory for Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, Jiangsu, China.
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Tang RJ, Meng SF, Zheng XJ, Zhang B, Yang Y, Wang C, Fu AG, Zhao FG, Lan WZ, Luan S. Conserved mechanism for vacuolar magnesium sequestration in yeast and plant cells. NATURE PLANTS 2022; 8:181-190. [PMID: 35087208 DOI: 10.1038/s41477-021-01087-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 12/07/2021] [Indexed: 06/14/2023]
Abstract
Magnesium (Mg2+) is an essential nutrient for all life forms. In fungal and plant cells, the majority of Mg2+ is stored in the vacuole but mechanisms for Mg2+ transport into the vacuolar store are not fully understood. Here we demonstrate that members of ancient conserved domain proteins (ACDPs) from Saccharomyces cerevisiae and Arabidopsis thaliana function in vacuolar Mg2+ sequestration that enables plant and yeast cells to cope with high levels of external Mg2+. We show that the yeast genome (as well as other fungal genomes) harbour a single ACDP homologue, referred to as MAM3, that functions specifically in vacuolar Mg2+ accumulation and is essential for tolerance to high Mg. In parallel, vacuolar ACDP homologues were identified from Arabidopsis and shown to complement the yeast mutant mam3Δ. An Arabidopsis mutant lacking one of the vacuolar ACDP homologues displayed hypersensitivity to high-Mg conditions and accumulated less Mg in the vacuole compared with the wild type. Taken together, our results suggest that conserved transporters mediate vacuolar Mg2+ sequestration in fungal and plant cells to maintain cellular Mg2+ homeostasis in response to fluctuating Mg2+ levels in the environment.
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Affiliation(s)
- Ren-Jie Tang
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - Su-Fang Meng
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Xiao-Jiang Zheng
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
- College of Life Sciences, Northwest University, Xi'an, China
| | - Bin Zhang
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, China
- College of Life Sciences, Northwest University, Xi'an, China
| | - Yang Yang
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Chao Wang
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
- College of Life Sciences, Northwest University, Xi'an, China
| | - Ai-Gen Fu
- College of Life Sciences, Northwest University, Xi'an, China
| | - Fu-Geng Zhao
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, China
| | - Wen-Zhi Lan
- Nanjing University-Nanjing Forestry University Joint Institute for Plant Molecular Biology, State Key Laboratory for Pharmaceutical Biotechnology, College of Life Sciences, Nanjing University, Nanjing, China.
| | - Sheng Luan
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.
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Robinson JR, Isikhuemhen OS, Anike FN. Fungal-Metal Interactions: A Review of Toxicity and Homeostasis. J Fungi (Basel) 2021; 7:225. [PMID: 33803838 PMCID: PMC8003315 DOI: 10.3390/jof7030225] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 03/15/2021] [Accepted: 03/17/2021] [Indexed: 12/18/2022] Open
Abstract
Metal nanoparticles used as antifungals have increased the occurrence of fungal-metal interactions. However, there is a lack of knowledge about how these interactions cause genomic and physiological changes, which can produce fungal superbugs. Despite interest in these interactions, there is limited understanding of resistance mechanisms in most fungi studied until now. We highlight the current knowledge of fungal homeostasis of zinc, copper, iron, manganese, and silver to comprehensively examine associated mechanisms of resistance. Such mechanisms have been widely studied in Saccharomyces cerevisiae, but limited reports exist in filamentous fungi, though they are frequently the subject of nanoparticle biosynthesis and targets of antifungal metals. In most cases, microarray analyses uncovered resistance mechanisms as a response to metal exposure. In yeast, metal resistance is mainly due to the down-regulation of metal ion importers, utilization of metallothionein and metallothionein-like structures, and ion sequestration to the vacuole. In contrast, metal resistance in filamentous fungi heavily relies upon cellular ion export. However, there are instances of resistance that utilized vacuole sequestration, ion metallothionein, and chelator binding, deleting a metal ion importer, and ion storage in hyphal cell walls. In general, resistance to zinc, copper, iron, and manganese is extensively reported in yeast and partially known in filamentous fungi; and silver resistance lacks comprehensive understanding in both.
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Affiliation(s)
| | - Omoanghe S. Isikhuemhen
- Department of Natural Resources and Environmental Design, North Carolina Agricultural and Technical State University, 1601 East Market Street, Greensboro, NC 27411, USA; (J.R.R.); (F.N.A.)
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Mg2+-ATP Sensing in CNNM, a Putative Magnesium Transporter. Structure 2020; 28:324-335.e4. [DOI: 10.1016/j.str.2019.11.016] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 11/06/2019] [Accepted: 11/27/2019] [Indexed: 01/10/2023]
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Giménez-Mascarell P, Schirrmacher CE, Martínez-Cruz LA, Müller D. Novel Aspects of Renal Magnesium Homeostasis. Front Pediatr 2018; 6:77. [PMID: 29686978 PMCID: PMC5900390 DOI: 10.3389/fped.2018.00077] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 03/13/2018] [Indexed: 12/29/2022] Open
Abstract
Magnesium (Mg2+) is indispensable for several vital functions, such as neurotransmission, cardiac conductance, blood glucose, blood pressure regulation, and proper function of more than 300 enzymes. Thus, Mg2+ homeostasis is subject to tight regulation. Besides the fast and immediate regulation of plasma Mg2+, a major part of Mg2+ homeostasis is realized by a concerted action of epithelial molecular structures that tightly control intestinal uptake and renal absorption. This mechanism is provided by a combination of para- and transcellular pathways. Whereas the first pathway provides the organism with a maximal amount of vital substances by a minimal energy expenditure, the latter enables controlling and fine-tuning by means of local and regional regulatory systems and also, hormonal control. The paracellular pathway is driven by an electrochemical gradient and realized in principal by the tight junction (TJ), a supramolecular organization of membrane-bound proteins and their adaptor and scaffolding proteins. TJ determinants are claudins (CLDN), a family of membrane spanning proteins that generate a barrier or a pore between two adjacent epithelial cells. Many insights into molecular mechanisms of Mg2+ handling have been achieved by the identification of alterations and mutations in human genes which cause disorders of paracellular Mg2+ pathways (CLDN10, CLDN14, CLDN16, CLDN19). Also, in the distal convoluted tubule, a basolateral protein, CNNM2, causes if mutated, familial dominant and also recessive renal Mg2+ wasting, albeit its true function has not been clarified yet, but is assumed to play a key role in the transcellular pathway. Moreover, mutations in human genes that are involved in regulating these proteins directly or indirectly cause, if mutated human diseases, mostly in combination with comorbidities as diabetes, cystic renal disease, or metabolic abnormalities. Generation and characterization of animal models harboring the corresponding mutations have further contributed to the elucidation of physiology and pathophysiology of Mg2+ disorders. Finally, high-end crystallization techniques allow understanding of Mg2+ handling in more detail. As this field is rapidly growing, we describe here the principles of physiology and pathophysiology of epithelial transport of renal Mg2+ homeostasis with emphasis on recently identified mechanisms involved.
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Affiliation(s)
| | - Carlotta Else Schirrmacher
- Department of Pediatric Gastroenterology, Nephrology and Metabolism, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | | | - Dominik Müller
- Department of Pediatric Gastroenterology, Nephrology and Metabolism, Charité - Universitätsmedizin Berlin, Berlin, Germany
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Sinharoy S, Liu C, Breakspear A, Guan D, Shailes S, Nakashima J, Zhang S, Wen J, Torres-Jerez I, Oldroyd G, Murray JD, Udvardi MK. A Medicago truncatula Cystathionine-β-Synthase-like Domain-Containing Protein Is Required for Rhizobial Infection and Symbiotic Nitrogen Fixation. PLANT PHYSIOLOGY 2016; 170:2204-17. [PMID: 26884486 PMCID: PMC4825145 DOI: 10.1104/pp.15.01853] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 02/03/2016] [Indexed: 05/19/2023]
Abstract
The symbiosis between leguminous plants and soil rhizobia culminates in the formation of nitrogen-fixing organs called nodules that support plant growth. Two Medicago truncatula Tnt1-insertion mutants were identified that produced small nodules, which were unable to fix nitrogen effectively due to ineffective rhizobial colonization. The gene underlying this phenotype was found to encode a protein containing a putative membrane-localized domain of unknown function (DUF21) and a cystathionine-β-synthase domain. The cbs1 mutants had defective infection threads that were sometimes devoid of rhizobia and formed small nodules with greatly reduced numbers of symbiosomes. We studied the expression of the gene, designated M truncatula Cystathionine-β-Synthase-like1 (MtCBS1), using a promoter-β-glucuronidase gene fusion, which revealed expression in infected root hair cells, developing nodules, and in the invasion zone of mature nodules. An MtCBS1-GFP fusion protein localized itself to the infection thread and symbiosomes. Nodulation factor-induced Ca(2+) responses were observed in the cbs1 mutant, indicating that MtCBS1 acts downstream of nodulation factor signaling. MtCBS1 expression occurred exclusively during Medicago-rhizobium symbiosis. Induction of MtCBS1 expression during symbiosis was found to be dependent on Nodule Inception (NIN), a key transcription factor that controls both rhizobial infection and nodule organogenesis. Interestingly, the closest homolog of MtCBS1, MtCBS2, was specifically induced in mycorrhizal roots, suggesting common infection mechanisms in nodulation and mycorrhization. Related proteins in Arabidopsis have been implicated in cell wall maturation, suggesting a potential role for CBS1 in the formation of the infection thread wall.
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Affiliation(s)
- Senjuti Sinharoy
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
| | - Chengwu Liu
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
| | - Andrew Breakspear
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
| | - Dian Guan
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
| | - Sarah Shailes
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
| | - Jin Nakashima
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
| | - Shulan Zhang
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
| | - Jiangqi Wen
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
| | - Ivone Torres-Jerez
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
| | - Giles Oldroyd
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
| | - Jeremy D Murray
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
| | - Michael K Udvardi
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, Oklahoma 73401 (S.S., J.N., S.Z., J.W., I.T.-J., M.K.U.); and John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, UK (C.L., A.B., D.G., S.S., I.T.-J., G.O., J.D.M.)
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12
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Fokina AV, Chechenova MB, Karginov AV, Ter-Avanesyan MD, Agaphonov MO. Genetic Evidence for the Role of the Vacuole in Supplying Secretory Organelles with Ca2+ in Hansenula polymorpha. PLoS One 2015; 10:e0145915. [PMID: 26717478 PMCID: PMC4696657 DOI: 10.1371/journal.pone.0145915] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/10/2015] [Indexed: 11/18/2022] Open
Abstract
Processes taking place in the secretory organelles require Ca2+ and Mn2+, which in yeast are supplied by the Pmr1 ion pump. Here we observed that in the yeast Hansenula polymorpha Ca2+ deficiency in the secretory pathway caused by Pmr1 inactivation is exacerbated by (i) the ret1-27 mutation affecting COPI-mediated vesicular transport, (ii) inactivation of the vacuolar Ca2+ ATPase Pmc1 and (iii) inactivation of Vps35, which is a component of the retromer complex responsible for protein transport between the vacuole and secretory organelles. The ret1-27 mutation also exerted phenotypes indicating alterations in transport between the vacuole and secretory organelles. These data indicate that ret1-27, pmc1 and vps35 affect a previously unknown Pmr1-independent route of the Ca2+ delivery to the secretory pathway. We also observed that the vacuolar protein carboxypeptidase Y receives additional modifications of its glycoside chains if it escapes the Vps10-dependent sorting to the vacuole.
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Affiliation(s)
- Anastasia V. Fokina
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Maria B. Chechenova
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Azamat V. Karginov
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Michael D. Ter-Avanesyan
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
| | - Michael O. Agaphonov
- A.N. Bach Institute of Biochemistry, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
- * E-mail:
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13
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Nucleotide binding triggers a conformational change of the CBS module of the magnesium transporter CNNM2 from a twisted towards a flat structure. Biochem J 2015; 464:23-34. [PMID: 25184538 DOI: 10.1042/bj20140409] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Recent studies suggest CNNM2 (cyclin M2) to be part of the long-sought basolateral Mg2+ extruder at the renal distal convoluted tubule, or its regulator. In the present study, we explore structural features and ligand-binding capacities of the Bateman module of CNNM2 (residues 429-584), an intracellular domain structurally equivalent to the region involved in Mg2+ handling by the bacterial Mg2+ transporter MgtE, and AMP binding by the Mg2+ efflux protein CorC. Additionally, we studied the structural impact of the pathogenic mutation T568I located in this region. Our crystal structures reveal that nucleotides such as AMP, ADP or ATP bind at only one of the two cavities present in CNNM2429-584. Mg2+ favours ATP binding by alleviating the otherwise negative charge repulsion existing between acidic residues and the polyphosphate group of ATP. In crystals CNNM2429-584 forms parallel dimers, commonly referred to as CBS (cystathionine β-synthase) modules. Interestingly, nucleotide binding triggers a conformational change in the CBS module from a twisted towards a flat disc-like structure that mostly affects the structural elements connecting the Bateman module with the transmembrane region. We furthermore show that the T568I mutation, which causes dominant hypomagnesaemia, mimics the structural effect induced by nucleotide binding. The results of the present study suggest that the T568I mutation exerts its pathogenic effect in humans by constraining the conformational equilibrium of the CBS module of CNNM2, which becomes 'locked' in its flat form.
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14
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Islam Z, Hayashi N, Inoue H, Umezawa T, Kimura Y, Doi H, Romero MF, Hirose S, Kato A. Identification and lateral membrane localization of cyclin M3, likely to be involved in renal Mg2+ handling in seawater fish. Am J Physiol Regul Integr Comp Physiol 2014; 307:R525-37. [PMID: 24965791 DOI: 10.1152/ajpregu.00032.2014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The kidney of marine teleosts is the major site of Mg(2+) excretion and produces urine with a high Mg(2+) concentration. However, the transporters involved in Mg(2+) excretion are poorly understood. The cyclin M (Cnnm; also known as ancient conserved domain protein) family comprises membrane proteins homologous to the bacterial Mg(2+) and Co(2+) efflux protein, CorC. To understand the molecular mechanism of Mg(2+) homeostasis in marine teleosts, we analyzed the expression of the Cnnm family genes in the seawater (SW) pufferfish, torafugu (Takifugu rubripes), and the closely related euryhaline species, mefugu (Takifugu obscurus). Database mining and phylogenetic analysis indicated that the Takifugu genome contains six members of the Cnnm family: two orthologs of Cnnm1, one of Cnnm2, one of Cnnm3, and two of Cnnm4. RT-PCR analyses indicated that Cnnm2, Cnnm3, and Cnnm4a are expressed in the kidney, whereas other members are mainly expressed in the brain. Renal expression of Cnnm3 was upregulated in SW mefugu, whereas renal expression of Cnnm2 was upregulated in freshwater (FW) mefugu. No significant difference was observed in renal expression of Cnnm4a between SW and FW mefugu. In situ hybridization and immunohistochemical analyses of the SW mefugu kidney revealed that Cnnm3 is expressed in the proximal tubule, and its product localizes to the lateral membrane. When Cnnm3 was expressed in Xenopus laevis oocytes, whole cellular Mg(2+) content and free intracellular Mg(2+) activity significantly decreased. These results suggest that Cnnm3 is involved in body fluid Mg(2+) homeostasis in marine teleosts.
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Affiliation(s)
- Zinia Islam
- Department of Biological Sciences, Tokyo Institute of Technology, Yokohama, Japan
| | - Naoko Hayashi
- Department of Biological Sciences, Tokyo Institute of Technology, Yokohama, Japan
| | - Hana Inoue
- Department of Physiology, Tokyo Medical University, Tokyo, Japan
| | - Takahiro Umezawa
- Department of Biological Sciences, Tokyo Institute of Technology, Yokohama, Japan
| | - Yuuri Kimura
- Department of Biological Sciences, Tokyo Institute of Technology, Yokohama, Japan
| | - Hiroyuki Doi
- Shimonoseki Marine Science Museum, Shimonoseki, Japan
| | - Michael F Romero
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, Minnesota; Nephrology and Hypertension, Mayo Clinic College of Medicine, Rochester, Minnesota; and O'Brien Urology Research Center, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Shigehisa Hirose
- Department of Biological Sciences, Tokyo Institute of Technology, Yokohama, Japan
| | - Akira Kato
- Department of Biological Sciences, Tokyo Institute of Technology, Yokohama, Japan; Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, Minnesota;
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15
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Gómez-García I, Stuiver M, Ereño J, Oyenarte I, Corral-Rodríguez MA, Müller D, Martínez-Cruz LA. Purification, crystallization and preliminary crystallographic analysis of the CBS-domain pair of cyclin M2 (CNNM2). Acta Crystallogr Sect F Struct Biol Cryst Commun 2012; 68:1198-203. [PMID: 23027747 PMCID: PMC3497979 DOI: 10.1107/s1744309112035348] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 08/09/2012] [Indexed: 05/13/2024]
Abstract
This work describes the purification and preliminary crystallographic analysis of the CBS-domain pair of the murine CNNM2 magnesium transporter (formerly known as ancient domain protein 2; ACDP2), which consists of a pair of cystathionine β-synthase (CBS) motifs and has 100% sequence identity to its human homologue. CNNM proteins represent the least-studied members of the eight different types of magnesium transporters identified to date in mammals. In humans, the CNNM family is encoded by four genes: CNNM1-4. CNNM1 acts as a cytosolic copper chaperone, whereas CNNM2 and CNNM4 have been associated with magnesium handling. Interestingly, mutations in the CNNM2 gene cause familial dominant hypomagnesaemia (MIM:607803), a rare human disorder characterized by renal and intestinal magnesium (Mg(2+)) wasting, which may lead to symptoms of Mg(2+) depletion such as tetany, seizures and cardiac arrhythmias. This manuscript describes the preliminary crystallographic analysis of two different crystal habits of a truncated form of the protein containing its regulatory CBS-domain pair, which has been reported to host the pathological mutation T568I in humans. The crystals belonged to space groups P2(1)2(1)2 and I222 (or I2(1)2(1)2(1)) and diffracted X-rays to 2.0 and 3.6 Å resolution, respectively, using synchrotron radiation.
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Affiliation(s)
- Inmaculada Gómez-García
- Structural Biology Unit, CIC bioGUNE, Parque Tecnológico de Bizkaia, Edificio 800, 48160 Derio, Bizkaia, Spain
| | - Marchel Stuiver
- Department of Pediatric Nephrology, Charité Universitätsmedizin, 13353 Berlin, Germany
| | - June Ereño
- Structural Biology Unit, CIC bioGUNE, Parque Tecnológico de Bizkaia, Edificio 800, 48160 Derio, Bizkaia, Spain
| | - Iker Oyenarte
- Structural Biology Unit, CIC bioGUNE, Parque Tecnológico de Bizkaia, Edificio 800, 48160 Derio, Bizkaia, Spain
| | | | - Dominik Müller
- Department of Pediatric Nephrology, Charité Universitätsmedizin, 13353 Berlin, Germany
| | - Luis Alfonso Martínez-Cruz
- Structural Biology Unit, CIC bioGUNE, Parque Tecnológico de Bizkaia, Edificio 800, 48160 Derio, Bizkaia, Spain
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16
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Chesi A, Kilaru A, Fang X, Cooper AA, Gitler AD. The role of the Parkinson's disease gene PARK9 in essential cellular pathways and the manganese homeostasis network in yeast. PLoS One 2012; 7:e34178. [PMID: 22457822 PMCID: PMC3311584 DOI: 10.1371/journal.pone.0034178] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Accepted: 02/27/2012] [Indexed: 02/01/2023] Open
Abstract
YPK9 (Yeast PARK9; also known as YOR291W) is a non-essential yeast gene predicted by sequence to encode a transmembrane P-type transport ATPase. However, its substrate specificity is unknown. Mutations in the human homolog of YPK9, ATP13A2/PARK9, have been linked to genetic forms of early onset parkinsonism. We previously described a strong genetic interaction between Ypk9 and another Parkinson's disease (PD) protein α-synuclein in multiple model systems, and a role for Ypk9 in manganese detoxification in yeast. In humans, environmental exposure to toxic levels of manganese causes a syndrome similar to PD and is thus an environmental risk factor for the disease. How manganese contributes to neurodegeneration is poorly understood. Here we describe multiple genome-wide screens in yeast aimed at defining the cellular function of Ypk9 and the mechanisms by which it protects cells from manganese toxicity. In physiological conditions, we found that Ypk9 genetically interacts with essential genes involved in cellular trafficking and the cell cycle. Deletion of Ypk9 sensitizes yeast cells to exposure to excess manganese. Using a library of non-essential gene deletions, we screened for additional genes involved in tolerance to excess manganese exposure, discovering several novel pathways involved in manganese homeostasis. We defined the dependence of the deletion strain phenotypes in the presence of manganese on Ypk9, and found that Ypk9 deletion modifies the manganese tolerance of only a subset of strains. These results confirm a role for Ypk9 in manganese homeostasis and illuminates cellular pathways and biological processes in which Ypk9 likely functions.
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Affiliation(s)
- Alessandra Chesi
- Department of Genetics, Stanford University School of Medicine, Stanford University, Stanford, California, United States of America
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Austin Kilaru
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Xiaodong Fang
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Antony A. Cooper
- Garvan Institute of Medical Research, University of New South Wales, Sydney, New South Wales, Australia
| | - Aaron D. Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford University, Stanford, California, United States of America
- * E-mail:
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17
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A genome-wide immunodetection screen in S. cerevisiae uncovers novel genes involved in lysosomal vacuole function and morphology. PLoS One 2011; 6:e23696. [PMID: 21912603 PMCID: PMC3166051 DOI: 10.1371/journal.pone.0023696] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Accepted: 07/22/2011] [Indexed: 11/19/2022] Open
Abstract
Vacuoles of yeast Saccharomyces cerevisiae are functionally analogous to mammalian lysosomes. Both are cellular organelles responsible for macromolecular degradation, ion/pH homeostasis, and stress survival. We hypothesized that undefined gene functions remain at post-endosomal stage of vacuolar events and performed a genome-wide screen directed at such functions at the late endosome and vacuole interface – ENV genes. The immunodetection screen was designed to identify mutants that internally accumulate precursor form of the vacuolar hydrolase carboxypeptidase Y (CPY). Here, we report the uncovering and initial characterizations of twelve ENV genes. The small size of the collection and the lack of genes previously identified with vacuolar events are suggestive of the intended exclusive functional interface of the screen. Most notably, the collection includes four novel genes ENV7, ENV9, ENV10, and ENV11, and three genes previously linked to mitochondrial processes – MAM3, PCP1, PPE1. In all env mutants, vesicular trafficking stages were undisturbed in live cells as assessed by invertase and active α-factor secretion, as well as by localization of the endocytic fluorescent marker FM4-64 to the vacuole. Several mutants exhibit defects in stress survival functions associated with vacuoles. Confocal fluorescence microscopy revealed the collection to be significantly enriched in vacuolar morphologies suggestive of fusion and fission defects. These include the unique phenotype of lumenal vesicles within vacuoles in the novel env9Δ mutant and severely fragmented vacuoles upon deletion of GET4, a gene recently implicated in tail anchored membrane protein insertion. Thus, our results establish new gene functions in vacuolar function and morphology, and suggest a link between vacuolar and mitochondrial events.
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18
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Gómez García I, Oyenarte I, Martínez-Cruz LA. Purification, crystallization and preliminary crystallographic analysis of the CBS pair of the human metal transporter CNNM4. Acta Crystallogr Sect F Struct Biol Cryst Commun 2011; 67:349-53. [PMID: 21393841 PMCID: PMC3053161 DOI: 10.1107/s1744309110053856] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Accepted: 12/22/2010] [Indexed: 04/23/2023]
Abstract
This work describes the purification and preliminary crystallographic analysis of the CBS-pair regulatory domain of the human ancient domain protein 4 (ACDP4), also known as CNNM4. ACDP proteins represent the least-studied members of the eight different types of magnesium transporters that have been identified in mammals to date. In humans the ACDP family includes four members: CNNM1-4. CNNM1 acts as a cytosolic copper chaperone and has been associated with urofacial syndrome, whereas CNNM2 and CNNM4 have been identified as magnesium transporters. Interestingly, mutations in the CNNM4 gene have clinical consequences that are limited to retinal function and biomineralization and are considered to be the cause of Jalili syndrome, which consists of autosomal recessive cone-rod dystrophy and amelogenesis imperfecta. The truncated protein was overexpressed, purified and crystallized in the orthorhombic space group C222. The crystals diffracted X-rays to 3.6 Å resolution using synchrotron radiation. Matthews volume calculations suggested the presence of two molecules in the asymmetric unit, which were likely to correspond to a CBS module of the CBS pair of CNNM4.
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Affiliation(s)
- Inmaculada Gómez García
- Structural Biology Unit, CIC bioGUNE, Edificio 800, Parque Tecnológico de Bizkaia, 48160 Derio, Bizkaia, Spain
| | - Iker Oyenarte
- Structural Biology Unit, CIC bioGUNE, Edificio 800, Parque Tecnológico de Bizkaia, 48160 Derio, Bizkaia, Spain
| | - Luis Alfonso Martínez-Cruz
- Structural Biology Unit, CIC bioGUNE, Edificio 800, Parque Tecnológico de Bizkaia, 48160 Derio, Bizkaia, Spain
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19
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Rosenfeld L, Reddi AR, Leung E, Aranda K, Jensen LT, Culotta VC. The effect of phosphate accumulation on metal ion homeostasis in Saccharomyces cerevisiae. J Biol Inorg Chem 2010; 15:1051-62. [PMID: 20429018 DOI: 10.1007/s00775-010-0664-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Accepted: 04/12/2010] [Indexed: 10/19/2022]
Abstract
Much of what is currently understood about the cell biology of metals involves their interactions with proteins. By comparison, little is known about interactions of metals with intracellular inorganic compounds such as phosphate. Here we examined the role of phosphate in metal metabolism in vivo by genetically perturbing the phosphate content of Saccharomyces cerevisiae cells. Yeast pho80 mutants cannot sense phosphate and have lost control of phosphate uptake, storage, and metabolism. We report here that pho80 mutants specifically elevate cytosolic and nonvacuolar levels of phosphate and this in turn causes a wide range of metal homeostasis defects. Intracellular levels of the hard-metal cations sodium and calcium increase dramatically, and cells become susceptible to toxicity from the transition metals manganese, cobalt, zinc, and copper. Disruptions in phosphate control also elicit an iron starvation response, as pho80 mutants were seen to upregulate iron transport genes. The iron-responsive transcription factor Aft1p appears activated in cells with high phosphate content in spite of normal intracellular iron levels. The high phosphate content of pho80 mutants can be lowered by mutating Pho4p, the transcription factor for phosphate uptake and storage genes. Such lowering of phosphate content by pho4 mutations reversed the high calcium and sodium content of pho80 mutants and prevented the iron starvation response. However, pho4 mutations only partially reversed toxicity from heavy metals, representing a novel outcome of phosphate dysregulation. Overall, these studies underscore the importance of maintaining a charge balance in the cell; a disruption in phosphate metabolism can dramatically impact on metal homeostasis.
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Affiliation(s)
- Leah Rosenfeld
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, 615N. Wolfe Street, Room E7626, Baltimore, MD 21205, USA
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20
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Quamme GA. Molecular identification of ancient and modern mammalian magnesium transporters. Am J Physiol Cell Physiol 2010; 298:C407-29. [DOI: 10.1152/ajpcell.00124.2009] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A large number of mammalian Mg2+ transporters have been hypothesized on the basis of physiological data, but few have been investigated at the molecular level. The recent identification of a number of novel proteins that mediate Mg2+ transport has enhanced our understanding of how Mg2+ is translocated across mammalian membranes. Some of these transporters have some similarity to those found in prokaryocytes and yeast cells. Human Mrs2, a mitochondrial Mg2+ channel, shares many of the properties of the bacterial CorA and yeast Alr1 proteins. The SLC41 family of mammalian Mg2+ transporters has a similarity with some regions of the bacterial MgtE transporters. The mammalian ancient conserved domain protein (ACDP) Mg2+ transporters are found in prokaryotes, suggesting an ancient origin. However, other newly identified mammalian transporters, including TRPM6/7, MagT, NIPA, MMgT, and HIP14 families, are not represented in prokaryotic genomes, suggesting more recent development. MagT, NIPA, MMgT, and HIP14 transporters were identified by differential gene expression using microarray analysis. These proteins, which are found in many different tissues and subcellular organelles, demonstrate a diversity of structural properties and biophysical functions. The mammalian Mg2+ transporters have no obvious amino acid similarities, indicating that there are many ways to transport Mg2+ across membranes. Most of these proteins transport a number of divalent cations across membranes. Only MagT1 and NIPA2 are selective for Mg2+. Many of the identified mammalian Mg2+ transporters are associated with a number of congenital disorders encompassing a wide range of tissues, including intestine, kidney, brain, nervous system, and skin. It is anticipated that future research will identify other novel Mg2+ transporters and reveal other diseases.
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Affiliation(s)
- Gary A. Quamme
- Vancouver Hospital, University of British Columbia, Vancouver, British Columbia, Canada
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21
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Affiliation(s)
- Amit R. Reddi
- Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, 615 North Wolfe Street, Baltimore, Maryland 21205
| | - Laran T. Jensen
- Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, 615 North Wolfe Street, Baltimore, Maryland 21205
| | - Valeria C. Culotta
- To whom correspondence should be addressed. . Phone: (410) 955-4712. Fax: (410) 955-0116
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22
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Jensen LT, Carroll MC, Hall MD, Harvey CJ, Beese SE, Culotta VC. Down-regulation of a manganese transporter in the face of metal toxicity. Mol Biol Cell 2009; 20:2810-9. [PMID: 19369420 PMCID: PMC2695789 DOI: 10.1091/mbc.e08-10-1084] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Revised: 03/24/2009] [Accepted: 04/08/2009] [Indexed: 11/11/2022] Open
Abstract
The yeast Smf1p Nramp manganese transporter is posttranslationally regulated by environmental manganese. Smf1p is stabilized at the cell surface with manganese starvation, but is largely degraded in the vacuole with physiological manganese through a mechanism involving the Rsp5p adaptor complex Bsd2p/Tre1p/Tre2p. We now describe an additional level of Smf1p regulation that occurs with toxicity from manganese, but not other essential metals. This regulation is largely Smf1p-specific. As with physiological manganese, toxic manganese triggers vacuolar degradation of Smf1p by trafficking through the multivesicular body. However, regulation by toxic manganese does not involve Bsd2p/Tre1p/Tre2p. Toxic manganese triggers both endocytosis of cell surface Smf1p and vacuolar targeting of intracellular Smf1p through the exocytic pathway. Notably, the kinetics of vacuolar targeting for Smf1p are relatively slow with toxic manganese and require prolonged exposures to the metal. Down-regulation of Smf1p by toxic manganese does not require transport activity of Smf1p, whereas such transport activity is needed for Smf1p regulation by manganese starvation. Furthermore, the responses to manganese starvation and manganese toxicity involve separate cellular compartments. We provide evidence that manganese starvation is sensed within the lumen of the secretory pathway, whereas manganese toxicity is sensed within an extra-Golgi/cytosolic compartment of the cell.
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Affiliation(s)
- Laran T Jensen
- Department of Environmental Health Sciences and Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA.
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23
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Affiliation(s)
- Zhaohua Dai
- a Department of Chemistry and Physical Sciences , Pace University , New York, USA
- b Department of Chemistry , New York University , New York, USA
| | - Nikhil Khosla
- a Department of Chemistry and Physical Sciences , Pace University , New York, USA
| | - James W. Canary
- b Department of Chemistry , New York University , New York, USA
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24
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Polok B, Escher P, Ambresin A, Chouery E, Bolay S, Meunier I, Nan F, Hamel C, Munier FL, Thilo B, Mégarbané A, Schorderet DF. Mutations in CNNM4 cause recessive cone-rod dystrophy with amelogenesis imperfecta. Am J Hum Genet 2009; 84:259-65. [PMID: 19200527 DOI: 10.1016/j.ajhg.2009.01.006] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Revised: 12/30/2008] [Accepted: 01/13/2009] [Indexed: 02/06/2023] Open
Abstract
Cone-rod dystrophies are inherited dystrophies of the retina characterized by the accumulation of deposits mainly localized to the cone-rich macular region of the eye. Dystrophy can be limited to the retina or be part of a syndrome. Unlike nonsyndromic cone-rod dystrophies, syndromic cone-rod dystrophies are genetically heterogeneous with mutations in genes encoding structural, cell-adhesion, and transporter proteins. Using a genome-wide single-nucleotide polymorphism (SNP) haplotype analysis to fine map the locus and a gene-candidate approach, we identified homozygous mutations in the ancient conserved domain protein 4 gene (CNNM4) that either generate a truncated protein or occur in highly conserved regions of the protein. Given that CNNM4 is implicated in metal ion transport, cone-rod dystrophy and amelogenesis imperfecta may originate from abnormal ion homeostasis.
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Ruotolo R, Marchini G, Ottonello S. Membrane transporters and protein traffic networks differentially affecting metal tolerance: a genomic phenotyping study in yeast. Genome Biol 2008; 9:R67. [PMID: 18394190 PMCID: PMC2643938 DOI: 10.1186/gb-2008-9-4-r67] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2007] [Revised: 02/26/2008] [Accepted: 04/07/2008] [Indexed: 01/01/2023] Open
Abstract
Genomic phenotyping was used to assess the role of all non-essential S. cerevisiae proteins in modulating cell viability after exposure to cadmium, nickel and other metals. Background The cellular mechanisms that underlie metal toxicity and detoxification are rather variegated and incompletely understood. Genomic phenotyping was used to assess the roles played by all nonessential Saccharomyces cerevisiae proteins in modulating cell viability after exposure to cadmium, nickel, and other metals. Results A number of novel genes and pathways that affect multimetal as well as metal-specific tolerance were discovered. Although the vacuole emerged as a major hot spot for metal detoxification, we also identified a number of pathways that play a more general, less direct role in promoting cell survival under stress conditions (for example, mRNA decay, nucleocytoplasmic transport, and iron acquisition) as well as proteins that are more proximally related to metal damage prevention or repair. Most prominent among the latter are various nutrient transporters previously not associated with metal toxicity. A strikingly differential effect was observed for a large set of deletions, the majority of which centered on the ESCRT (endosomal sorting complexes required for transport) and retromer complexes, which - by affecting transporter downregulation and intracellular protein traffic - cause cadmium sensitivity but nickel resistance. Conclusion The data show that a previously underestimated variety of pathways are involved in cadmium and nickel tolerance in eukaryotic cells. As revealed by comparison with five additional metals, there is a good correlation between the chemical properties and the cellular toxicity signatures of various metals. However, many conserved pathways centered on membrane transporters and protein traffic affect cell viability with a surprisingly high degree of metal specificity.
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Affiliation(s)
- Roberta Ruotolo
- Department of Biochemistry and Molecular Biology, Viale G.P. Usberti 23/A, University of Parma, I-43100 Parma, Italy
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Alderton A, Davies P, Illman K, Brown DR. Ancient conserved domain protein-1 binds copper and modifies its retention in cells. J Neurochem 2007; 103:312-21. [PMID: 17608643 DOI: 10.1111/j.1471-4159.2007.04751.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The ancient conserved domain protein (ACDP) family are a recently identified group of homologous mammalian proteins. Some family members have been suggested to have roles in the metabolism of metals. We investigated the capacity of ACDP-1 to bind metals. Using immobilised metal affinity chromatography and isothermal titration calorimetry we determined that ACDP-1 is a high affinity copper binding protein able to bind copper at nanomolar concentrations. In addition the promoter of ACDP-1 contains metal response elements and the cellular expression of ACDP-1 alters cellular retention of copper. However, cellular expression of ACDP-1 does not alter cellular resistance to the toxicity of copper or other metals. As our findings place the subcellular localisation of ACDP-1 in the cytoplasm it is possible that ACDP-1 represent a novel copper chaperone or storage protein.
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Shao Z, Sun F. Intracellular sequestration of manganese and phosphorus in a metal-resistant fungus Cladosporium cladosporioides from deep-sea sediment. Extremophiles 2007; 11:435-43. [PMID: 17265162 DOI: 10.1007/s00792-006-0051-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2006] [Accepted: 11/21/2006] [Indexed: 10/23/2022]
Abstract
A heavy metal resistant fungus was isolated from the sediment of Pacific Ocean, and identified to be Cladosporium cladosporioides. It grew normally in a medium containing 60 mM Mn(2+) and could endure 1,200 mM as the highest concentration tested. Quantification analysis confirmed a high accumulation of Mn which was 58 mg/g in dried biomass. Under transmission electron microscope, many intracellular crystals were observed in the cytoplasm of the hypha cells grown in a Mn-rich medium, and varied from a few nanometers to 200 nm in length. Energy dispersive X-ray (EDX) analysis showed that the crystals were composed of manganese and phosphorus in atomic ratio of 1.6:1 (Mn/P). Further, factors which might influence the resistance of this fungus were investigated. As a result, its high resistance to Mn(2+) was found dependent on the presence of Mg(2+), and could be further enhanced by phosphate. However, the effect of phosphate was not observed without the presence of Mg(2+). In addition, the resistance was also influenced by pH of the medium, which was lost above pH 8. This is the first report on a fungus which showed a hyper resistance to manganese by forming a large quantity of intracellular Mn/P crystals.
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Affiliation(s)
- Zongze Shao
- Key Lab of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Daxue Road 178#, 361005, Xiamen, Fujian, China.
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Current awareness on yeast. Yeast 2005. [DOI: 10.1002/yea.1168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Khalimonchuk O, Rödel G. Biogenesis of cytochrome c oxidase. Mitochondrion 2005; 5:363-88. [PMID: 16199211 DOI: 10.1016/j.mito.2005.08.002] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2005] [Accepted: 08/10/2005] [Indexed: 11/20/2022]
Abstract
Cytochrome c oxidase (COX), the terminal enzyme of electron transport chains in some prokaryotes and in mitochondria, has been characterized in detail over many years. Recently, a number of new data on structural and functional aspects as well as on COX biogenesis emerged. COX biogenesis includes a variety of steps starting from translation to the formation of the mature complex. Each step involves a set of specific factors that assist translation of subunits, their translocation across membranes, insertion of essential cofactors, assembly and final maturation of the enzyme. In this review, we focus on the organization and biogenesis of COX.
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Affiliation(s)
- Oleh Khalimonchuk
- Institut für Genetik, Technische Universität Dresden, 01062 Dresden, Germany
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Culotta VC, Yang M, Hall MD. Manganese transport and trafficking: lessons learned from Saccharomyces cerevisiae. EUKARYOTIC CELL 2005; 4:1159-65. [PMID: 16002642 PMCID: PMC1168969 DOI: 10.1128/ec.4.7.1159-1165.2005] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Valeria Cizewski Culotta
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, 615 N. Wolfe St., Room E7626, Baltimore, MD 21205, USA.
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Goytain A, Quamme GA. Functional characterization of ACDP2 (ancient conserved domain protein), a divalent metal transporter. Physiol Genomics 2005; 22:382-9. [PMID: 15899945 DOI: 10.1152/physiolgenomics.00058.2005] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
We have begun to identify and characterize genes that are differentially expressed with low magnesium. One of these sequences conformed to the ancient conserved domain protein, ACDP2. Real-time RT-PCR of mRNA isolated from distal epithelial cells cultured in low-magnesium media relative to normal media and in kidney cortex of mice maintained on low-magnesium diets compared with those animals consuming normal diets confirmed that the ACDP2 transcript is responsive to magnesium. Mouse ACDP2 was cloned from mouse distal convoluted tubule cells, expressed in Xenopus laevis oocytes, and studied with two-electrode voltage-clamp studies. When expressed in oocytes, ACDP2 mediates saturable Mg2+ uptake with a Michaelis constant of 0.56 +/- 0.05 mM. Transport of Mg2+ by ACDP2 is rheogenic, is voltage-dependent, and is not coupled to Na+ or Cl- ions. Expressed ACDP2 transports a range of divalent cations: Mg2+, Co2+, Mn2+, Sr2+, Ba2+, Cu2+, and Fe2+; accordingly, it is a divalent cation transporter with wide substrate selectivity. The cations Ca2+, Cd2+, Zn2+, and Ni2+ did not induce currents, and only Zn2+ effectively inhibited transport. The ACDP2 transcript is abundantly present in kidney, brain, and heart with lower amounts in liver, small intestine, and colon. Moreover, ACDP2 mRNA is upregulated with magnesium deficiency, particularly in the distal convoluted tubule cells, kidney, heart, and brain. These studies suggest that ACDP2 may provide a regulated transporter for Mg2+ and other divalent cations in epithelial cells.
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Affiliation(s)
- Angela Goytain
- Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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Guo D, Ling J, Wang MH, She JX, Gu J, Wang CY. Physical interaction and functional coupling between ACDP4 and the intracellular ion chaperone COX11, an implication of the role of ACDP4 in essential metal ion transport and homeostasis. Mol Pain 2005; 1:15. [PMID: 15840172 PMCID: PMC1097757 DOI: 10.1186/1744-8069-1-15] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2005] [Accepted: 04/19/2005] [Indexed: 11/10/2022] Open
Abstract
Divalent metal ions such as copper, manganese, and cobalt are essential for cell development, differentiation, function and survival. These essential metal ions are delivered into intracellular domains as cofactors for enzymes involved in neuropeptide and neurotransmitter synthesis, superoxide metabolism, and other biological functions in a target specific fashion. Altering the homeostasis of these essential metal ions is known to connect to a number of human diseases including Alzheimer disease, amyotrophic lateral sclerosis, and pain. It remains unclear how these essential metal ions are delivered to intracellular targets in mammalian cells. Here we report that rat spinal cord dorsal horn neurons express ACDP4, a member of Ancient Conserved Domain Protein family. By screening a pretransformed human fetal brain cDNA library in a yeast two-hybrid system, we have identified that ACDP4 specifically interacts with COX11, an intracellular metal ion chaperone. Ectopic expression of ACDP4 in HEK293 cells resulted in enhanced toxicity to metal ions including copper, manganese, and cobalt. The metal ion toxicity became more pronounced when ACDP4 and COX11 were co-expressed ectopically in HEK293 cells, suggesting a functional coupling between them. Our results indicate a role of ACDP4 in metal ion homeostasis and toxicity. This is the first report revealing a functional aspect of this ancient conserved domain protein family. We propose that ACDP is a family of transporter protein or chaperone proteins for delivering essential metal ions in different mammalian tissues. The expression of ACDP4 on spinal cord dorsal horn neurons may have implications in sensory neuron functions under physiological and pathological conditions.
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Affiliation(s)
- Dehuang Guo
- Center for Biotechnology and Genomic Medicine, Medical College of Georgia, 1120 15Street, CA4098, Augusta, GA 30912, USA
| | - Jennifer Ling
- Department of Oral and Maxillofacial Surgery, Mcknight Brain Institute and College of Dentistry, University of Florida, Gainesville, Florida, 32610, USA
| | - Mong-Heng Wang
- Department of Physiology, Medical College of Georgia, 1120 15Street, Augusta, GA 30912, USA
| | - Jin-Xiong She
- Center for Biotechnology and Genomic Medicine, Medical College of Georgia, 1120 15Street, CA4098, Augusta, GA 30912, USA
| | - Jianguo Gu
- Department of Oral and Maxillofacial Surgery, Mcknight Brain Institute and College of Dentistry, University of Florida, Gainesville, Florida, 32610, USA
| | - Cong-Yi Wang
- Center for Biotechnology and Genomic Medicine, Medical College of Georgia, 1120 15Street, CA4098, Augusta, GA 30912, USA
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