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Querci L, Piccioli M, Ciofi-Baffoni S, Banci L. Structural aspects of iron‑sulfur protein biogenesis: An NMR view. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119786. [PMID: 38901495 DOI: 10.1016/j.bbamcr.2024.119786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 05/15/2024] [Accepted: 06/10/2024] [Indexed: 06/22/2024]
Abstract
Over the last decade, structural aspects involving iron‑sulfur (Fe/S) protein biogenesis have played an increasingly important role in understanding the high mechanistic complexity of mitochondrial and cytosolic machineries maturing Fe/S proteins. In this respect, solution NMR has had a significant impact because of its ability to monitor transient protein-protein interactions, which are abundant in the networks of pathways leading to Fe/S cluster biosynthesis and transfer, as well as thanks to the developments of paramagnetic NMR in both terms of new methodologies and accurate data interpretation. Here, we review the use of solution NMR in characterizing the structural aspects of human Fe/S proteins and their interactions in the framework of Fe/S protein biogenesis. We will first present a summary of the recent advances that have been achieved by paramagnetic NMR and then we will focus our attention on the role of solution NMR in the field of human Fe/S protein biogenesis.
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Affiliation(s)
- Leonardo Querci
- Magnetic Resonance Center CERM, University of Florence, Via Luigi Sacconi 6, Sesto Fiorentino, 50019 Florence, Italy; Department of Chemistry, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019 Florence, Italy
| | - Mario Piccioli
- Magnetic Resonance Center CERM, University of Florence, Via Luigi Sacconi 6, Sesto Fiorentino, 50019 Florence, Italy; Department of Chemistry, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019 Florence, Italy
| | - Simone Ciofi-Baffoni
- Magnetic Resonance Center CERM, University of Florence, Via Luigi Sacconi 6, Sesto Fiorentino, 50019 Florence, Italy; Department of Chemistry, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019 Florence, Italy.
| | - Lucia Banci
- Magnetic Resonance Center CERM, University of Florence, Via Luigi Sacconi 6, Sesto Fiorentino, 50019 Florence, Italy; Department of Chemistry, University of Florence, Via della Lastruccia 3, Sesto Fiorentino, 50019 Florence, Italy; Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), Via Luigi Sacconi 6, Sesto Fiorentino, 50019 Florence, Italy.
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2
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Doni D, Cavallari E, Noguera ME, Gentili HG, Cavion F, Parisi G, Fornasari MS, Sartori G, Santos J, Bellanda M, Carbonera D, Costantini P, Bortolus M. Searching for Frataxin Function: Exploring the Analogy with Nqo15, the Frataxin-like Protein of Respiratory Complex I from Thermus thermophilus. Int J Mol Sci 2024; 25:1912. [PMID: 38339189 PMCID: PMC10855754 DOI: 10.3390/ijms25031912] [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: 12/23/2023] [Revised: 01/26/2024] [Accepted: 02/02/2024] [Indexed: 02/12/2024] Open
Abstract
Nqo15 is a subunit of respiratory complex I of the bacterium Thermus thermophilus, with strong structural similarity to human frataxin (FXN), a protein involved in the mitochondrial disease Friedreich's ataxia (FRDA). Recently, we showed that the expression of recombinant Nqo15 can ameliorate the respiratory phenotype of FRDA patients' cells, and this prompted us to further characterize both the Nqo15 solution's behavior and its potential functional overlap with FXN, using a combination of in silico and in vitro techniques. We studied the analogy of Nqo15 and FXN by performing extensive database searches based on sequence and structure. Nqo15's folding and flexibility were investigated by combining nuclear magnetic resonance (NMR), circular dichroism, and coarse-grained molecular dynamics simulations. Nqo15's iron-binding properties were studied using NMR, fluorescence, and specific assays and its desulfurase activation by biochemical assays. We found that the recombinant Nqo15 isolated from complex I is monomeric, stable, folded in solution, and highly dynamic. Nqo15 does not share the iron-binding properties of FXN or its desulfurase activation function.
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Affiliation(s)
- Davide Doni
- Department of Biology, University of Padova, 35121 Padova, Italy; (D.D.); (F.C.)
| | - Eva Cavallari
- Department of Biology, University of Padova, 35121 Padova, Italy; (D.D.); (F.C.)
- Grenoble Alpes University, CNRS, CEA, INRAE, IRIG-LPCV, 38000 Grenoble, France
| | - Martin Ezequiel Noguera
- Department of Physiology and Molecular and Cellular Biology, Institute of Biosciences, Biotechnology and Translational Biology (iB3), Faculty of Exact and Natural Sciences, University of Buenos Aires, Intendente Güiraldes 2160, Buenos Aires C1428EG, Argentina; (M.E.N.); (H.G.G.); (J.S.)
- Institute of Biological Chemistry and Physical Chemistry, Dr Alejandro Paladini (UBA-CONICET), University of Buenos Aires, Junín 956, Buenos Aires 1113AAD, Argentina
- Department of Science and Technology, National University of Quilmes, Roque Saenz Peña 352, Bernal B1876BXD, Argentina; (G.P.); (M.S.F.)
| | - Hernan Gustavo Gentili
- Department of Physiology and Molecular and Cellular Biology, Institute of Biosciences, Biotechnology and Translational Biology (iB3), Faculty of Exact and Natural Sciences, University of Buenos Aires, Intendente Güiraldes 2160, Buenos Aires C1428EG, Argentina; (M.E.N.); (H.G.G.); (J.S.)
| | - Federica Cavion
- Department of Biology, University of Padova, 35121 Padova, Italy; (D.D.); (F.C.)
| | - Gustavo Parisi
- Department of Science and Technology, National University of Quilmes, Roque Saenz Peña 352, Bernal B1876BXD, Argentina; (G.P.); (M.S.F.)
| | - Maria Silvina Fornasari
- Department of Science and Technology, National University of Quilmes, Roque Saenz Peña 352, Bernal B1876BXD, Argentina; (G.P.); (M.S.F.)
| | - Geppo Sartori
- Department of Biomedical Sciences, University of Padova, 35121 Padova, Italy;
| | - Javier Santos
- Department of Physiology and Molecular and Cellular Biology, Institute of Biosciences, Biotechnology and Translational Biology (iB3), Faculty of Exact and Natural Sciences, University of Buenos Aires, Intendente Güiraldes 2160, Buenos Aires C1428EG, Argentina; (M.E.N.); (H.G.G.); (J.S.)
| | - Massimo Bellanda
- Department of Chemical Sciences, University of Padova, 35131 Padova, Italy; (M.B.); (D.C.)
- Consiglio Nazionale delle Ricerche Institute of Biomolecular Chemistry, 35131 Padova, Italy
| | - Donatella Carbonera
- Department of Chemical Sciences, University of Padova, 35131 Padova, Italy; (M.B.); (D.C.)
| | - Paola Costantini
- Department of Biology, University of Padova, 35121 Padova, Italy; (D.D.); (F.C.)
| | - Marco Bortolus
- Department of Chemical Sciences, University of Padova, 35131 Padova, Italy; (M.B.); (D.C.)
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3
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Pignataro MF, Herrera MG, Fernández NB, Aran M, Gentili HG, Battaglini F, Santos J. Selection of synthetic proteins to modulate the human frataxin function. Biotechnol Bioeng 2023; 120:409-425. [PMID: 36225115 DOI: 10.1002/bit.28263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 09/13/2022] [Accepted: 10/09/2022] [Indexed: 01/13/2023]
Abstract
Frataxin is a kinetic activator of the mitochondrial supercomplex for iron-sulfur cluster assembly. Low frataxin expression or a decrease in its functionality results in Friedreich's Ataxia (FRDA). With the aim of creating new molecular tools to study this metabolic pathway, and ultimately, to explore new therapeutic strategies, we have investigated the possibility of obtaining small proteins exhibiting a high affinity for frataxin. In this study, we applied the ribosome display approach, using human frataxin as the target. We focused on Affi_224, one of the proteins that we were able to select after five rounds of selection. We have studied the interaction between both proteins and discussed some applications of this specific molecular tutor, concerning the modulation of the supercomplex activity. Affi_224 and frataxin showed a KD value in the nanomolar range, as judged by surface plasmon resonance analysis. Most likely, it binds to the frataxin acidic ridge, as suggested by the analysis of chemical shift perturbations (nuclear magnetic resonance) and computational simulations. Affi_224 was able to increase Cys NFS1 desulfurase activation exerted by the FRDA frataxin variant G130V. Importantly, Affi_224 interacts with frataxin in a human cellular model. Our results suggest quaternary addition may be a new tool to modulate frataxin function in vivo. Nevertheless, more functional experiments under physiological conditions should be carried out to evaluate Affi_224 effectiveness in FRDA cell models.
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Affiliation(s)
- María Florencia Pignataro
- Departamento de Fisiología y Biología Molecular y Celular, Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes, Ciudad Autónoma de Buenos Aires, Argentina
| | - María Georgina Herrera
- Departamento de Fisiología y Biología Molecular y Celular, Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes, Ciudad Autónoma de Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
| | - Natalia Brenda Fernández
- Departamento de Fisiología y Biología Molecular y Celular, Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes, Ciudad Autónoma de Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
| | - Martín Aran
- Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina.,Fundación Instituto Leloir, IIBBA-CONICET, Buenos Aires, Argentina
| | - Hernán Gustavo Gentili
- Departamento de Fisiología y Biología Molecular y Celular, Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes, Ciudad Autónoma de Buenos Aires, Argentina
| | - Fernando Battaglini
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE CONICET), Buenos Aires, Argentina
| | - Javier Santos
- Departamento de Fisiología y Biología Molecular y Celular, Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes, Ciudad Autónoma de Buenos Aires, Argentina.,Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina
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Characteristics of the Isu1 C-terminus in relation to [2Fe-2S] cluster assembly and ISCU Myopathy. J Biol Inorg Chem 2022; 27:759-773. [PMID: 36309885 DOI: 10.1007/s00775-022-01964-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 09/30/2022] [Indexed: 01/05/2023]
Abstract
Mitochondrial [2Fe-2S] cluster biosynthesis is driven by the coordinated activities of the Iron-Sulfur Cluster (ISC) pathway protein machinery. Within the ISC machinery, the protein that provides a structural scaffold on which [2Fe-2S] clusters are assembled is the ISCU protein in humans; this protein is referred to as the "Scaffold" protein. Truncation of the C-terminal portion of ISCU causes the fatal disease "ISCU Myopathy", which exhibits phenotypes of reduced Fe-S cluster assembly in cells. In this report, the yeast ISCU ortholog "Isu1" has been characterized to gain a better understanding of the role of the scaffold protein in relation to [2Fe-2S] assembly and ISCU Myopathy. Here we explored the biophysical characteristics of the C-terminal region of Isu1, the segment of the protein that is truncated on the human ortholog during the disease ISCU Myopathy. We characterized the role of this region in relation to iron binding, protein stability, assembly of the ISC multiprotein complex required to accomplish Fe-S cluster assembly, and finally on overall cell viability. We determined the Isu1 C-terminus is essential for the completion of the Fe-S cluster assembly but serves a function independent of protein iron binding.
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Campbell CJ, Pall AE, Naik AR, Thompson LN, Stemmler TL. Molecular Details of the Frataxin-Scaffold Interaction during Mitochondrial Fe-S Cluster Assembly. Int J Mol Sci 2021; 22:6006. [PMID: 34199378 PMCID: PMC8199681 DOI: 10.3390/ijms22116006] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 05/27/2021] [Accepted: 05/28/2021] [Indexed: 12/23/2022] Open
Abstract
Iron-sulfur clusters are essential to almost every life form and utilized for their unique structural and redox-targeted activities within cells during many cellular pathways. Although there are three different Fe-S cluster assembly pathways in prokaryotes (the NIF, SUF and ISC pathways) and two in eukaryotes (CIA and ISC pathways), the iron-sulfur cluster (ISC) pathway serves as the central mechanism for providing 2Fe-2S clusters, directly and indirectly, throughout the entire cell in eukaryotes. Proteins central to the eukaryotic ISC cluster assembly complex include the cysteine desulfurase, a cysteine desulfurase accessory protein, the acyl carrier protein, the scaffold protein and frataxin (in humans, NFS1, ISD11, ACP, ISCU and FXN, respectively). Recent molecular details of this complex (labeled NIAUF from the first letter from each ISC protein outlined earlier), which exists as a dimeric pentamer, have provided real structural insight into how these partner proteins arrange themselves around the cysteine desulfurase, the core dimer of the (NIAUF)2 complex. In this review, we focus on both frataxin and the scaffold within the human, fly and yeast model systems to provide a better understanding of the biophysical characteristics of each protein alone and within the FXN/ISCU complex as it exists within the larger NIAUF construct. These details support a complex dynamic interaction between the FXN and ISCU proteins when both are part of the NIAUF complex and this provides additional insight into the coordinated mechanism of Fe-S cluster assembly.
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Affiliation(s)
| | | | | | | | - Timothy L. Stemmler
- Department of Pharmaceutical Sciences, Wayne State University, Detroit, MI 48201, USA; (C.J.C.); (A.E.P.); (A.R.N.); (L.N.T.)
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6
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Cai K, Frederick RO, Markley JL. ISCU interacts with NFU1, and ISCU[4Fe-4S] transfers its Fe-S cluster to NFU1 leading to the production of holo-NFU1. J Struct Biol 2020; 210:107491. [PMID: 32151725 PMCID: PMC7261492 DOI: 10.1016/j.jsb.2020.107491] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/17/2020] [Accepted: 03/04/2020] [Indexed: 01/30/2023]
Abstract
NFU1 is a late-acting factor in the biogenesis of human mitochondrial iron-sulfur proteins. Mutations in NFU1 are associated with genetic diseases such as multiple mitochondrial dysfunctions syndrome 1 (MMDS1) that involve defects in mitochondrial [4Fe-4S] proteins. We present results from NMR spectroscopy, small angle X-ray scattering, size exclusion chromatography, and isothermal titration calorimetry showing that the structured conformer of human ISCU binds human NFU1. The dissociation constant determined by ITC is Kd = 1.1 ± 0.2 μM. NMR and SAXS studies led to a structural model for the complex in which the cluster binding region of ISCU interacts with two α-helices in the C-terminal domain of NFU1. In vitro experiments demonstrate that ISCU[4Fe-4S] transfers its Fe-S cluster to apo-NFU1, in the absence of a chaperone, leading to the assembly of holo-NFU1. By contrast, the cluster of ISCU[2Fe-2S] remains bound to ISCU in the presence of apo-NFU1.
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Affiliation(s)
- Kai Cai
- Biochemistry Department, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Ronnie O Frederick
- Biochemistry Department, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - John L Markley
- Biochemistry Department, University of Wisconsin-Madison, Madison, WI 53706, USA
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7
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Baussier C, Fakroun S, Aubert C, Dubrac S, Mandin P, Py B, Barras F. Making iron-sulfur cluster: structure, regulation and evolution of the bacterial ISC system. Adv Microb Physiol 2020; 76:1-39. [PMID: 32408945 DOI: 10.1016/bs.ampbs.2020.01.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Iron sulfur (Fe-S) clusters rank among the most ancient and conserved prosthetic groups. Fe-S clusters containing proteins are present in most, if not all, organisms. Fe-S clusters containing proteins are involved in a wide range of cellular processes, from gene regulation to central metabolism, via gene expression, RNA modification or bioenergetics. Fe-S clusters are built by biogenesis machineries conserved throughout both prokaryotes and eukaryotes. We focus mostly on bacterial ISC machinery, but not exclusively, as we refer to eukaryotic ISC system when it brings significant complementary information. Besides covering the structural and regulatory aspects of Fe-S biogenesis, this review aims to highlight Fe-S biogenesis facets remaining matters of discussion, such as the role of frataxin, or the link between fatty acid metabolism and Fe-S homeostasis. Last, we discuss recent advances on strategies used by different species to make and use Fe-S clusters in changing redox environmental conditions.
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Affiliation(s)
- Corentin Baussier
- Laboratoire de Chimie Bactérienne, CNRS-Aix Marseille Université, UMR 7283, Institut de Microbiologie de la Méditerranée, Institut de Microbiologie, Bioénergies et Biotechnologies, Marseille, France
| | - Soufyan Fakroun
- Stress Adaptation and Metabolism Unit, Department of Microbiology, Institut Pasteur, Paris, France; ERL CNRS 6002, CNRS, Paris, France; Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Corinne Aubert
- Laboratoire de Chimie Bactérienne, CNRS-Aix Marseille Université, UMR 7283, Institut de Microbiologie de la Méditerranée, Institut de Microbiologie, Bioénergies et Biotechnologies, Marseille, France
| | - Sarah Dubrac
- Stress Adaptation and Metabolism Unit, Department of Microbiology, Institut Pasteur, Paris, France; ERL CNRS 6002, CNRS, Paris, France
| | - Pierre Mandin
- Laboratoire de Chimie Bactérienne, CNRS-Aix Marseille Université, UMR 7283, Institut de Microbiologie de la Méditerranée, Institut de Microbiologie, Bioénergies et Biotechnologies, Marseille, France
| | - Béatrice Py
- Laboratoire de Chimie Bactérienne, CNRS-Aix Marseille Université, UMR 7283, Institut de Microbiologie de la Méditerranée, Institut de Microbiologie, Bioénergies et Biotechnologies, Marseille, France
| | - Frédéric Barras
- Stress Adaptation and Metabolism Unit, Department of Microbiology, Institut Pasteur, Paris, France; ERL CNRS 6002, CNRS, Paris, France
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8
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Tanaka N, Yuda E, Fujishiro T, Hirabayashi K, Wada K, Takahashi Y. Identification of IscU residues critical for de novo iron-sulfur cluster assembly. Mol Microbiol 2019; 112:1769-1783. [PMID: 31532036 DOI: 10.1111/mmi.14392] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2019] [Indexed: 01/16/2023]
Abstract
IscU is a central component of the ISC machinery and serves as a scaffold for the de novo assembly of iron-sulfur (Fe-S) clusters prior to their delivery to target apo-Fe-S proteins. However, the molecular mechanism is not yet fully understood. In this study, we have conducted mutational analysis of E. coli IscU using the recently developed genetic complementation system of a mutant that can survive without Fe-S clusters. The Fe-S cluster ligands (C37, C63, H105, C106) and the proximal D39 and K103 residues are essential for in vivo function of IscU and could not be substituted with any other amino acids. Furthermore, we found that substitution of Y3, a strictly conserved residue among IscU homologs, abolished in vivo functions. Surprisingly, a second-site suppressor mutation in IscS (A349V) reverted the defect caused by IscU Y3 substitutions. Biochemical analysis revealed that IscU Y3 was crucial for functional interaction with IscS and sulfur transfer between the two proteins. Our findings suggest that the critical role of IscU Y3 is linked to the conformational dynamics of the flexible loop of IscS, which is required for the ingenious sulfur transfer to IscU.
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Affiliation(s)
- Naoyuki Tanaka
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Eiki Yuda
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Takashi Fujishiro
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Kei Hirabayashi
- Department of Medical Sciences, University of Miyazaki, Miyazaki, 889-1692, Japan
| | - Kei Wada
- Department of Medical Sciences, University of Miyazaki, Miyazaki, 889-1692, Japan
| | - Yasuhiro Takahashi
- Department of Biochemistry and Molecular Biology, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama, 338-8570, Japan
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9
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Lewis BE, Mason Z, Rodrigues AV, Nuth M, Dizin E, Cowan JA, Stemmler TL. Unique roles of iron and zinc binding to the yeast Fe-S cluster scaffold assembly protein "Isu1". Metallomics 2019; 11:1820-1835. [PMID: 31532427 DOI: 10.1039/c9mt00172g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Mitochondrial Fe-S cluster biosynthesis is accomplished within yeast utilizing the biophysical attributes of the "Isu1" scaffold assembly protein. As a member of a highly homologous protein family, Isu1 has sequence conservation between orthologs and a conserved ability to assemble [2Fe-2S] clusters. Regardless of species, scaffold orthologs have been shown to exist in both "disordered" and "structured" conformations, a structural architecture that is directly related to conformations utilized during Fe-S cluster assembly. During assembly, the scaffold helps direct the delivery and utilization of Fe(ii) and persulfide substrates to produce [2Fe-2S] clusters, however Zn(ii) binding alters the activity of the scaffold while at the same time stabilizes the protein in its structured state. Additional studies confirm Zn binds to the scaffold's Cys rich active site, and has an impact on the protein's ability to make Fe-S clusters. Understanding the interplay between Fe(ii) and Zn(ii) binding to Isu1 in vitro may help clarify metal loading events that occur during Fe-S cluster assembly in vivo. Here we determine the metal : protein stoichiometry for Isu1 Zn and Fe binding to be 1 : 1 and 2 : 1, respectively. As expected, while Zn binding shifts the Isu1 to its structured state, folding is not influenced by Fe(ii) binding. X-ray absorption spectroscopy (XAS) confirms Zn(ii) binds to the scaffold's cysteine rich active site but Fe(ii) binds at a location distinct from the active site. XAS results show Isu1 binding initially of either Fe(ii) or Zn(ii) does not significantly perturb the metal site structure of alternate metal. XAS confirmed that four scaffold orthologs bind iron as high-spin Fe(ii) at a site composed of ca. 6 oxygen and nitrogen nearest neighbor ligands. Finally, in our report Zn binding dramatically reduces the Fe-S cluster assembly activity of Isu1 even in the presence of frataxin. Given the Fe-binding activity we report for Isu1 and its orthologs here, a possible mechanism involving Fe(ii) transport to the scaffold's active site during cluster assembly has been considered.
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Affiliation(s)
- Brianne E Lewis
- Department of Pharmaceutical Science, Wayne State University, Detroit, MI 48201, USA.
| | - Zachary Mason
- Department of Pharmaceutical Science, Wayne State University, Detroit, MI 48201, USA.
| | - Andria V Rodrigues
- Department of Pharmaceutical Science, Wayne State University, Detroit, MI 48201, USA.
| | - Manunya Nuth
- Department of Chemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Eric Dizin
- Department of Chemistry, The Ohio State University, Columbus, OH 43210, USA
| | - J A Cowan
- Department of Chemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Timothy L Stemmler
- Department of Pharmaceutical Science, Wayne State University, Detroit, MI 48201, USA.
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10
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Petrosino M, Pasquo A, Novak L, Toto A, Gianni S, Mantuano E, Veneziano L, Minicozzi V, Pastore A, Puglisi R, Capriotti E, Chiaraluce R, Consalvi V. Characterization of human frataxin missense variants in cancer tissues. Hum Mutat 2019; 40:1400-1413. [PMID: 31074541 PMCID: PMC6744310 DOI: 10.1002/humu.23789] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 04/17/2019] [Accepted: 05/06/2019] [Indexed: 12/19/2022]
Abstract
Human frataxin is an iron-binding protein involved in the mitochondrial iron-sulfur (Fe-S) clusters assembly, a process fundamental for the functional activity of mitochondrial proteins. Decreased level of frataxin expression is associated with the neurodegenerative disease Friedreich ataxia. Defective function of frataxin may cause defects in mitochondria, leading to increased tumorigenesis. Tumor-initiating cells show higher iron uptake, a decrease in iron storage and a reduced Fe-S clusters synthesis and utilization. In this study, we selected, from COSMIC database, the somatic human frataxin missense variants found in cancer tissues p.D104G, p.A107V, p.F109L, p.Y123S, p.S161I, p.W173C, p.S181F, and p.S202F to analyze the effect of the single amino acid substitutions on frataxin structure, function, and stability. The spectral properties, the thermodynamic and the kinetic stability, as well as the molecular dynamics of the frataxin missense variants found in cancer tissues point to local changes confined to the environment of the mutated residues. The global fold of the variants is not altered by the amino acid substitutions; however, some of the variants show a decreased stability and a decreased functional activity in comparison with that of the wild-type protein.
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Affiliation(s)
- Maria Petrosino
- Dipartimento di Scienze Biochimiche “A. Rossi Fanelli”. Sapienza University of Rome, Rome, Italy
- Current address: IRCCS Istituto Neurologico Carlo Besta, Milano, Italia
- European Brain Research Institute-Fondazione Rita Levi Montalcini, Roma, Italia
| | - Alessandra Pasquo
- ENEA CR Frascati, Diagnostics and Metrology Laboratory,FSN-TECFIS-DIM, Frascati, Italy
| | - Leonore Novak
- Dipartimento di Scienze Biochimiche “A. Rossi Fanelli”. Sapienza University of Rome, Rome, Italy
| | - Angelo Toto
- Dipartimento di Scienze Biochimiche “A. Rossi Fanelli”. Sapienza University of Rome, Rome, Italy
- Istituto di Biologia e Patologia Molecolari del CNR, Sapienza Università di Roma, Rome, Italy
| | - Stefano Gianni
- Dipartimento di Scienze Biochimiche “A. Rossi Fanelli”. Sapienza University of Rome, Rome, Italy
- Istituto di Biologia e Patologia Molecolari del CNR, Sapienza Università di Roma, Rome, Italy
| | - Elide Mantuano
- Institute of Translational Pharmacology, CNR, Rome, Italy
| | | | - Velia Minicozzi
- INFN and Department of Physics, University of Rome Tor Vergata, Rome, Italy
| | - Annalisa Pastore
- The Wohl Institute, King’s College London, London, United Kingdom
| | - Rita Puglisi
- The Wohl Institute, King’s College London, London, United Kingdom
| | - Emidio Capriotti
- Department of Pharmacy and Biotechnology (FaBiT), University of Bologna, Bologna, Italy
| | - Roberta Chiaraluce
- Dipartimento di Scienze Biochimiche “A. Rossi Fanelli”. Sapienza University of Rome, Rome, Italy
| | - Valerio Consalvi
- Dipartimento di Scienze Biochimiche “A. Rossi Fanelli”. Sapienza University of Rome, Rome, Italy
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11
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Das D, Patra S, Bridwell-Rabb J, Barondeau DP. Mechanism of frataxin "bypass" in human iron-sulfur cluster biosynthesis with implications for Friedreich's ataxia. J Biol Chem 2019; 294:9276-9284. [PMID: 30975898 PMCID: PMC6556584 DOI: 10.1074/jbc.ra119.007716] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/10/2019] [Indexed: 11/06/2022] Open
Abstract
In humans, mitochondrial iron-sulfur cluster biosynthesis is an essential biochemical process mediated by the assembly complex consisting of cysteine desulfurase (NFS1), LYR protein (ISD11), acyl-carrier protein (ACP), and the iron-sulfur cluster assembly scaffold protein (ISCU2). The protein frataxin (FXN) is an allosteric activator that binds the assembly complex and stimulates the cysteine desulfurase and iron-sulfur cluster assembly activities. FXN depletion causes loss of activity of iron-sulfur-dependent enzymes and the development of the neurodegenerative disease Friedreich's ataxia. Recently, a mutation that suppressed the loss of the FXN homolog in Saccharomyces cerevisiae was identified that encodes an amino acid substitution equivalent to the human variant ISCU2 M140I. Here, we developed iron-sulfur cluster synthesis and transfer functional assays and determined that the human ISCU2 M140I variant can substitute for FXN in accelerating the rate of iron-sulfur cluster formation on the monothiol glutaredoxin (GRX5) acceptor protein. Incorporation of both FXN and the M140I substitution had an additive effect, suggesting an acceleration of distinct steps in iron-sulfur cluster biogenesis. In contrast to the canonical role of FXN in stimulating the formation of [2Fe-2S]-ISCU2 intermediates, we found here that the M140I substitution in ISCU2 promotes the transfer of iron-sulfur clusters to GRX5. Together, these results reveal an unexpected mechanism that replaces FXN-based stimulation of the iron-sulfur cluster biosynthetic pathway and suggest new strategies to overcome the loss of cellular FXN that may be relevant to the development of therapeutics for Friedreich's ataxia.
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Affiliation(s)
- Deepika Das
- From the Department of Chemistry, Texas A & M University, College Station, Texas 77842
| | - Shachin Patra
- From the Department of Chemistry, Texas A & M University, College Station, Texas 77842
| | | | - David P Barondeau
- From the Department of Chemistry, Texas A & M University, College Station, Texas 77842
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12
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Ast T, Meisel JD, Patra S, Wang H, Grange RMH, Kim SH, Calvo SE, Orefice LL, Nagashima F, Ichinose F, Zapol WM, Ruvkun G, Barondeau DP, Mootha VK. Hypoxia Rescues Frataxin Loss by Restoring Iron Sulfur Cluster Biogenesis. Cell 2019; 177:1507-1521.e16. [PMID: 31031004 PMCID: PMC6911770 DOI: 10.1016/j.cell.2019.03.045] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 02/11/2019] [Accepted: 03/22/2019] [Indexed: 12/16/2022]
Abstract
Friedreich's ataxia (FRDA) is a devastating, multisystemic disorder caused by recessive mutations in the mitochondrial protein frataxin (FXN). FXN participates in the biosynthesis of Fe-S clusters and is considered to be essential for viability. Here we report that when grown in 1% ambient O2, FXN null yeast, human cells, and nematodes are fully viable. In human cells, hypoxia restores steady-state levels of Fe-S clusters and normalizes ATF4, NRF2, and IRP2 signaling events associated with FRDA. Cellular studies and in vitro reconstitution indicate that hypoxia acts through HIF-independent mechanisms that increase bioavailable iron as well as directly activate Fe-S synthesis. In a mouse model of FRDA, breathing 11% O2 attenuates the progression of ataxia, whereas breathing 55% O2 hastens it. Our work identifies oxygen as a key environmental variable in the pathogenesis associated with FXN depletion, with important mechanistic and therapeutic implications.
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Affiliation(s)
- Tslil Ast
- Broad Institute, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Howard Hughes Medical Institute, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Joshua D Meisel
- Broad Institute, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Howard Hughes Medical Institute, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Shachin Patra
- Department of Chemistry, Texas A&M University, College Station, TX 77843, USA
| | - Hong Wang
- Broad Institute, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Howard Hughes Medical Institute, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Robert M H Grange
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Sharon H Kim
- Broad Institute, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Howard Hughes Medical Institute, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Sarah E Calvo
- Broad Institute, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Howard Hughes Medical Institute, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Lauren L Orefice
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Fumiaki Nagashima
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Fumito Ichinose
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Warren M Zapol
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Gary Ruvkun
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Medical School, Boston, MA 02115, USA
| | - David P Barondeau
- Department of Chemistry, Texas A&M University, College Station, TX 77843, USA
| | - Vamsi K Mootha
- Broad Institute, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Howard Hughes Medical Institute, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Harvard Medical School, Boston, MA 02115, USA.
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13
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Tsvetkov P, Detappe A, Cai K, Keys HR, Brune Z, Ying W, Thiru P, Reidy M, Kugener G, Rossen J, Kocak M, Kory N, Tsherniak A, Santagata S, Whitesell L, Ghobrial IM, Markley JL, Lindquist S, Golub TR. Mitochondrial metabolism promotes adaptation to proteotoxic stress. Nat Chem Biol 2019; 15:681-689. [PMID: 31133756 PMCID: PMC8183600 DOI: 10.1038/s41589-019-0291-9] [Citation(s) in RCA: 272] [Impact Index Per Article: 54.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 04/16/2019] [Indexed: 12/17/2022]
Abstract
The mechanisms by which cells adapt to proteotoxic stress are largely unknown, but key to understanding how tumor cells, particularly in vivo, are largely resistant to proteasome inhibitors. Analysis of cancer cell lines, mouse xenografts and patient-derived tumor samples all showed an association between mitochondrial metabolism and proteasome inhibitor sensitivity. When cells were forced to use oxidative phosphorylation rather than glycolysis, they became proteasome inhibitor-resistant. This mitochondrial state, however, creates a unique vulnerability: sensitivity to the small-molecule compound elesclomol. Genome-wide CRISPR/Cas9 screening showed that a single gene, encoding the mitochondrial reductase FDX1, could rescue elesclomol-induced cell death. Enzymatic function and NMR-based analyses further showed that FDX1 is the direct target of elesclomol, which promotes a unique form of copper-dependent cell death. These studies elucidate a fundamental mechanism by which cells adapt to proteotoxic stress and suggests strategies to mitigate proteasome inhibitor-resistance.
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Affiliation(s)
| | - Alexandre Detappe
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Kai Cai
- Biochemistry Department, University of Wisconsin-Madison, Madison, WI, USA
| | - Heather R Keys
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | - Zarina Brune
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | - Weiwen Ying
- OnTarget Pharmaceutical Consulting LLC, Lexington, MA, USA
| | - Prathapan Thiru
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | - Mairead Reidy
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | | | - Jordan Rossen
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Mustafa Kocak
- Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Nora Kory
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | | | - Sandro Santagata
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Ludwig Center at Harvard, Harvard Medical School, Boston, MA, USA
| | - Luke Whitesell
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA.,Molecular Genetics Department, University of Toronto, Toronto, ON, Canada
| | - Irene M Ghobrial
- Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - John L Markley
- Biochemistry Department, University of Wisconsin-Madison, Madison, WI, USA
| | - Susan Lindquist
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA.,Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Todd R Golub
- Broad Institute of Harvard and MIT, Cambridge, MA, USA. .,Howard Hughes Medical Institute, Chevy Chase, MD, USA. .,Harvard Medical School, Boston, MA, USA. .,Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.
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14
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NMR as a Tool to Investigate the Processes of Mitochondrial and Cytosolic Iron-Sulfur Cluster Biosynthesis. Molecules 2018; 23:molecules23092213. [PMID: 30200358 PMCID: PMC6205161 DOI: 10.3390/molecules23092213] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/03/2018] [Accepted: 08/20/2018] [Indexed: 12/15/2022] Open
Abstract
Iron-sulfur (Fe-S) clusters, the ubiquitous protein cofactors found in all kingdoms of life, perform a myriad of functions including nitrogen fixation, ribosome assembly, DNA repair, mitochondrial respiration, and metabolite catabolism. The biogenesis of Fe-S clusters is a multi-step process that involves the participation of many protein partners. Recent biophysical studies, involving X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), and small angle X-ray scattering (SAXS), have greatly improved our understanding of these steps. In this review, after describing the biological importance of iron sulfur proteins, we focus on the contributions of NMR spectroscopy has made to our understanding of the structures, dynamics, and interactions of proteins involved in the biosynthesis of Fe-S cluster proteins.
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15
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Cai K, Frederick RO, Dashti H, Markley JL. Architectural Features of Human Mitochondrial Cysteine Desulfurase Complexes from Crosslinking Mass Spectrometry and Small-Angle X-Ray Scattering. Structure 2018; 26:1127-1136.e4. [PMID: 29983374 PMCID: PMC6082693 DOI: 10.1016/j.str.2018.05.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 04/16/2018] [Accepted: 05/24/2018] [Indexed: 11/19/2022]
Abstract
Cysteine desulfurase plays a central role in mitochondrial iron-sulfur cluster biogenesis by generating sulfur through the conversion of L-cysteine to L-alanine and by serving as the platform for assembling other components of the biosynthetic machinery, including ISCU, frataxin, and ferredoxin. The human mitochondrial cysteine desulfurase complex consists of two copies each of NFS1, ISD11, and acyl carrier protein. We describe results from chemical crosslinking coupled with tandem mass spectrometry and small-angle X-ray scattering studies that are consistent with a closed NFS1 dimer rather than an open one for both the cysteine desulfurase-ISCU and cysteine desulfurase-ISCU-frataxin complexes. We present a structural model for the cysteine desulfurase-ISCU-frataxin complex derived from chemical crosslinking restraints in conjunction with the recent crystal structure of the cysteine desulfurase-ISCU-zinc complex and distance constraints from nuclear magnetic resonance.
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Affiliation(s)
- Kai Cai
- Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, USA
| | - Ronnie O Frederick
- Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, USA
| | - Hesam Dashti
- Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, USA
| | - John L Markley
- Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, USA.
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16
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Cai K, Frederick RO, Tonelli M, Markley JL. Interactions of iron-bound frataxin with ISCU and ferredoxin on the cysteine desulfurase complex leading to Fe-S cluster assembly. J Inorg Biochem 2018; 183:107-116. [PMID: 29576242 PMCID: PMC5951399 DOI: 10.1016/j.jinorgbio.2018.03.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 03/08/2018] [Accepted: 03/12/2018] [Indexed: 12/15/2022]
Abstract
Frataxin (FXN) is involved in mitochondrial iron‑sulfur (Fe-S) cluster biogenesis and serves to accelerate Fe-S cluster formation. FXN deficiency is associated with Friedreich ataxia, a neurodegenerative disease. We have used a combination of isothermal titration calorimetry and multinuclear NMR spectroscopy to investigate interactions among the components of the biological machine that carries out the assembly of iron‑sulfur clusters in human mitochondria. Our results show that FXN tightly binds a single Fe2+ but not Fe3+. While FXN (with or without bound Fe2+) does not bind the scaffold protein ISCU directly, the two proteins interact mutually when each is bound to the cysteine desulfurase complex ([NFS1]2:[ISD11]2:[Acp]2), abbreviated as (NIA)2, where "N" represents the cysteine desulfurase (NFS1), "I" represents the accessory protein (ISD11), and "A" represents acyl carrier protein (Acp). FXN binds (NIA)2 weakly in the absence of ISCU but more strongly in its presence. Fe2+-FXN binds to the (NIA)2-ISCU2 complex without release of iron. However, upon the addition of both l-cysteine and a reductant (either reduced FDX2 or DTT), Fe2+ is released from FXN as consistent with Fe2+-FXN being the proximal source of iron for Fe-S cluster assembly.
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Affiliation(s)
- Kai Cai
- National Magnetic Resonance Facility at Madison and Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, United States
| | - Ronnie O Frederick
- National Magnetic Resonance Facility at Madison and Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, United States
| | - Marco Tonelli
- National Magnetic Resonance Facility at Madison and Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, United States
| | - John L Markley
- National Magnetic Resonance Facility at Madison and Biochemistry Department, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, United States.
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