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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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Gentili HG, Pignataro MF, Olmos J, Pavan MF, Ibañez LI, Santos J, Velazquez Duarte F. CRISPR/Cas9-based edition of frataxin gene in Dictyostelium discoideum. Biochem J 2023; 480:1533-1551. [PMID: 37721041 DOI: 10.1042/bcj20230244] [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: 06/26/2023] [Revised: 09/11/2023] [Accepted: 09/15/2023] [Indexed: 09/19/2023]
Abstract
In this paper, we describe the development of a Dictyostelium discoideum strain deficient in frataxin protein (FXN). We investigated the conservation of function between humans and D. discoideum and showed that DdFXN can substitute the human version in the interaction and activation of the Fe-S assembly supercomplex. We edited the D. discoideum fxn locus and isolated a defective mutant, clone 8, which presents landmarks of frataxin deficiency, such as a decrease in Fe-S cluster-dependent enzymatic functions, growth rate reduction, and increased sensitivity to oxidative stress. In addition, the multicellular development is affected as well as growing on bacterial lawn. We also assessed the rescuing capacity of DdFXN-G122V, a version that mimics a human variant present in some FA patients. While the expression of DdFXN-G122V rescues growth and enzymatic activity defects, as DdFXN does, multicellular development defects were only partially rescued. The results of the study suggest that this new D. discoideum strain offers a wide range of possibilities to easily explore diverse FA FXN variants. This can facilitate the development of straightforward drug screenings to look for new therapeutic strategies.
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Affiliation(s)
- Hernan G Gentili
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
| | - María Florencia Pignataro
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
| | - Justo Olmos
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
| | - María Florencia Pavan
- Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), CONICET, FCEN, UBA, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
| | - Lorena Itatí Ibañez
- Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE), CONICET, FCEN, UBA, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
| | - Javier Santos
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
| | - Francisco Velazquez Duarte
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina
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3
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Sewell KE, Gola GF, Pignataro MF, Herrera MG, Noguera ME, Olmos J, Ramírez JA, Capece L, Aran M, Santos J. Direct Cysteine Desulfurase Activity Determination by NMR and the Study of the Functional Role of Key Structural Elements of Human NFS1. ACS Chem Biol 2023; 18:1534-1547. [PMID: 37410592 DOI: 10.1021/acschembio.3c00147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/08/2023]
Abstract
The mitochondrial cysteine desulfurase NFS1 is an essential PLP-dependent enzyme involved in iron-sulfur cluster assembly. The enzyme catalyzes the desulfurization of the l-Cys substrate, producing a persulfide and l-Ala as products. In this study, we set the measurement of the product l-Ala by NMR in vitro by means of 1H NMR spectra acquisition. This methodology provided us with the possibility of monitoring the reaction in both fixed-time and real-time experiments, with high sensitivity and accuracy. By studying I452A, W454A, Q456A, and H457A NFS1 variants, we found that the C-terminal stretch (CTS) of the enzyme is critical for function. Specifically, mutation of the extremely conserved position W454 resulted in highly decreased activity. Additionally, we worked on two singular variants: "GGG" and C158A. In the former, the catalytic Cys-loop was altered by including two Gly residues to increase the flexibility of this loop. This variant had significantly impaired activity, indicating that the Cys-loop motions are fine-tuned in the wild-type enzyme. In turn, for C158A, we found an unanticipated increase in l-Cys desulfurase activity. Furthermore, we carried out molecular dynamics simulations of the supercomplex dedicated to iron-sulfur cluster biosynthesis, which includes NFS1, ACP, ISD11, ISCU2, and FXN subunits. We identified CTS as a key element that established interactions with ISCU2 and FXN concurrently; we found specific interactions that are established when FXN is present, reinforcing the idea that FXN not only forms part of the iron-sulfur cluster assembly site but also modulates the internal motions of ISCU2.
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Affiliation(s)
- Karl E Sewell
- Laboratorio de Genómica e Ingeniería de Sistemas Biológicos. Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Autónoma de Buenos Aires C1428EGA, Argentina
| | - Gabriel F Gola
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina
- Unidad de Microanálisis y Métodos Físicos Aplicados a Química Orgánica (UMYMFOR), CONICET─Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina
| | - María Florencia Pignataro
- Laboratorio de Genómica e Ingeniería de Sistemas Biológicos. Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Autónoma de Buenos Aires C1428EGA, Argentina
| | - María Georgina Herrera
- Laboratorio de Genómica e Ingeniería de Sistemas Biológicos. Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Autónoma de Buenos Aires C1428EGA, Argentina
| | - Martín E Noguera
- Laboratorio de Genómica e Ingeniería de Sistemas Biológicos. Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Autónoma de Buenos Aires C1428EGA, Argentina
- Instituto de Química y Físico-Química Biológicas, Universidad de Buenos Aires, Junín 956, Buenos Aires 1113AAD, Argentina
| | - Justo Olmos
- Laboratorio de Genómica e Ingeniería de Sistemas Biológicos. Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Autónoma de Buenos Aires C1428EGA, Argentina
| | - Javier A Ramírez
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina
- Unidad de Microanálisis y Métodos Físicos Aplicados a Química Orgánica (UMYMFOR), CONICET─Universidad de Buenos Aires, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina
| | - Luciana Capece
- Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Instituto de Química Física de los Materiales, Medio Ambiente y Energía (INQUIMAE CONICET), Universidad de Buenos Aires. Buenos Aires C1428EGA, Argentina
| | - Martín Aran
- Fundación Instituto Leloir, IIBBA-CONICET, and Plataforma Argentina de Biología Estructural y Metabolómica PLABEM, Av. Patricias Argentinas 435, Buenos Aires C1405BWE, Argentina
| | - Javier Santos
- Laboratorio de Genómica e Ingeniería de Sistemas Biológicos. Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Autónoma de Buenos Aires C1428EGA, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Rivadavia 1917, Ciudad Autónoma de Buenos Aires C1033AAJ, Argentina
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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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Puglisi R. Protein Mutations and Stability, a Link with Disease: The Case Study of Frataxin. Biomedicines 2022; 10:biomedicines10020425. [PMID: 35203634 PMCID: PMC8962269 DOI: 10.3390/biomedicines10020425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 11/16/2022] Open
Abstract
Protein mutations may lead to pathologies by causing protein misfunction or propensity to degradation. For this reason, several studies have been performed over the years to determine the capability of proteins to retain their native conformation under stress condition as well as factors to explain protein stabilization and the mechanisms behind unfolding. In this review, we explore the paradigmatic example of frataxin, an iron binding protein involved in Fe–S cluster biogenesis, and whose impairment causes a neurodegenerative disease called Friedreich’s Ataxia (FRDA). We summarize what is known about most common point mutations identified so far in heterozygous FRDA patients, their effects on frataxin structure and function and the consequences of its binding with partners.
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Affiliation(s)
- Rita Puglisi
- UK Dementia Research Institute at the Wohl Institute of King's College London, London SE59RT, UK
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6
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Espeche LD, Sewell KE, Castro IH, Capece L, Pignataro MF, Dain L, Santos J. Conformational stability, dynamics and function of human frataxin: Tryptophan side chain interplay. Arch Biochem Biophys 2022; 715:109086. [PMID: 34801473 DOI: 10.1016/j.abb.2021.109086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 11/09/2021] [Accepted: 11/16/2021] [Indexed: 11/02/2022]
Abstract
In humans, the loss of frataxin results in Friedreich's Ataxia, a neurodegenerative disease, in which a deficit in the iron-sulfur cluster assembly is observed. In this work, we analyzed three frataxin variants in which one tryptophan was replaced by a glycine: W155G, W168G and W173G. As expected, given its localization in the assembly site, W155G was not able to activate the desulfurase activity of the supercomplex for iron-sulfur cluster assembly. In turn, W168G, which was significantly more unstable than W155G, was fully active. W173G, which was highly unstable as W168G, showed a significantly decreased activity, only slightly higher than W155G. As W168G and W173G were highly sensitive to proteolysis, we investigated the protein motions by molecular dynamic simulations. We observed that W173G may display altered motions at the Trp155 site. Furthermore, we revealed a H-bond network in which Trp155 takes part, involving residues Gln148, Asn151, Gln153 and Arg165. We suggest that this motion modulation that specifically alters the population of different Trp155 rotamers can be directly transferred to the assembly site, altering the dynamics of the ISCU His137 key residue. This hypothesis was also contrasted by means of molecular dynamic simulations of frataxin in the context of the complete supercomplex. We propose that the supercomplex requires very definite motions of Trp155 to consolidate the assembly site.
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Affiliation(s)
- Lucía D Espeche
- Departamento de Diagnóstico Genético, Centro Nacional de Genética Médica "Dr. Eduardo E. Castilla" A.N.L.I.S., Av. Las Heras 2670, C1425ASQ, C.A.B.A, Argentina
| | - Karl Ellioth Sewell
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina
| | - Ignacio H Castro
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina
| | - Luciana Capece
- 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), C1428EGA, Buenos Aires, Argentina.
| | - María Florencia Pignataro
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina
| | - Liliana Dain
- Departamento de Diagnóstico Genético, Centro Nacional de Genética Médica "Dr. Eduardo E. Castilla" A.N.L.I.S., Av. Las Heras 2670, C1425ASQ, C.A.B.A, Argentina; Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia 1917, C1033AAJ, Buenos Aires, Argentina
| | - Javier Santos
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia 1917, C1033AAJ, Buenos Aires, Argentina; Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina.
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Mompeán M, Treviño MÁ, Laurents DV. Partial structure, dampened mobility, and modest impact of a His tag in the SARS-CoV-2 Nsp2 C-terminal region. EUROPEAN BIOPHYSICS JOURNAL : EBJ 2021; 50:1129-1137. [PMID: 34633480 PMCID: PMC8503394 DOI: 10.1007/s00249-021-01575-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 09/10/2021] [Accepted: 10/03/2021] [Indexed: 11/30/2022]
Abstract
Intrinsically disordered proteins (IDPs) play essential roles in regulating physiological processes in eukaryotic cells. Many viruses use their own IDPs to "hack" these processes to deactivate host defenses and promote viral growth. Thus, viral IDPs are attractive drug targets. While IDPs are hard to study by X-ray crystallography or cryo-EM, atomic level information on their conformational preferences and dynamics can be obtained using NMR spectroscopy. SARS-CoV-2 Nsp2, whose C-terminal region (CtR) is predicted to be disordered, interacts with human proteins that regulate translation initiation and endosome vesicle sorting. Molecules that block these interactions could be valuable leads for drug development. The 13Cβ and backbone 13CO, 1HN, 13Cα, and 15N nuclei of Nsp2's 45-residue CtR were assigned and used to characterize its structure and dynamics in three contexts; namely: (1) retaining an N-terminal His tag, (2) without the His tag and with an adventitious internal cleavage, and (3) lacking both the His tag and the internal cleavage. Two five-residue segments adopting a minor extended population were identified. Overall, the dynamic behavior is midway between a completely rigid and a fully flexible chain. Whereas the presence of an N-terminal His tag and internal cleavage stiffen and loosen, respectively, neighboring residues, they do not affect the tendency of two regions to populate extended conformations.
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Affiliation(s)
- Miguel Mompeán
- "Rocasolano" Institute for Physical Chemistry, Spanish National Research Council, Serrano 119, 28006, Madrid, Spain
| | - Miguel Á Treviño
- "Rocasolano" Institute for Physical Chemistry, Spanish National Research Council, Serrano 119, 28006, Madrid, Spain
| | - Douglas V Laurents
- "Rocasolano" Institute for Physical Chemistry, Spanish National Research Council, Serrano 119, 28006, Madrid, Spain.
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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: 7] [Impact Index Per Article: 2.3] [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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9
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Castro IH, Bringas M, Doni D, Noguera ME, Capece L, Aran M, Blaustein M, Costantini P, Santos J. Relationship between activity and stability: Design and characterization of stable variants of human frataxin. Arch Biochem Biophys 2020; 691:108491. [PMID: 32707090 DOI: 10.1016/j.abb.2020.108491] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/26/2020] [Accepted: 07/08/2020] [Indexed: 11/16/2022]
Abstract
The relationships between conformational dynamics, stability and protein function are not obvious. Frataxin (FXN) is an essential protein that forms part of a supercomplex dedicated to the iron-sulfur (Fe-S) cluster assembly within the mitochondrial matrix. In humans, the loss of FXN expression or a decrease in its functionality results in Friedreich's Ataxia, a cardio-neurodegenerative disease. Recently, the way in which FXN interacts with the rest of the subunits of the supercomplex was uncovered. This opens a window to explore relationships between structural dynamics and function. In this study, we prepared a set of FXN variants spanning a broad range of conformational stabilities. Variants S160I, S160M and A204R were more stable than the wild-type and showed similar biological activity. Additionally, we prepared SILCAR, a variant that combines S160I, L203C and A204R mutations. SILCAR was 2.4 kcal mol-1 more stable and equally active. Some of the variants were significantly more resistant to proteolysis than the wild-type FXN. SILCAR showed the highest resistance, suggesting a more rigid structure. It was corroborated by means of molecular dynamics simulations. Relaxation dispersion NMR experiments comparing SILCAR and wild-type variants suggested similar internal motions in the microsecond to millisecond timescale. Instead, variant S157I showed higher denaturation resistance but a significant lower function, similarly to that observed for the FRDA variant N146K. We concluded that the contribution of particular side chains to the conformational stability of FXN might be highly subordinated to their impact on both the protein function and the stability of the functional supercomplex.
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Affiliation(s)
- Ignacio Hugo Castro
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina
| | - Mauro Bringas
- 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), C1428EGA, Buenos Aires, Argentina
| | - Davide Doni
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131, Padova, Italy
| | - Martin Ezequiel Noguera
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina; Instituto de Química y Fisicoquímica Biológicas, Dr. Alejandro Paladini, Universidad de Buenos Aires, CONICET, Junín 956, C1113AAD, Buenos Aires, Argentina
| | - Luciana Capece
- 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), C1428EGA, Buenos Aires, Argentina
| | - Martín Aran
- Fundación Instituto Leloir, IIBBA-CONICET, Av. Patricias Argentinas 435, C1405BWE, Buenos Aires, Argentina
| | - Matías Blaustein
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia 1917, C1033AAJ, Buenos Aires, Argentina
| | - Paola Costantini
- Department of Biology, University of Padova, Viale G. Colombo 3, 35131, Padova, Italy
| | - Javier Santos
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB(3)). Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia 1917, C1033AAJ, Buenos Aires, Argentina; Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Buenos Aires, Argentina.
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10
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Olmos J, Pignataro MF, Benítez dos Santos AB, Bringas M, Klinke S, Kamenetzky L, Velazquez F, Santos J. A Highly Conserved Iron-Sulfur Cluster Assembly Machinery between Humans and Amoeba Dictyostelium discoideum: The Characterization of Frataxin. Int J Mol Sci 2020; 21:E6821. [PMID: 32957566 PMCID: PMC7554988 DOI: 10.3390/ijms21186821] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 09/05/2020] [Accepted: 09/14/2020] [Indexed: 12/17/2022] Open
Abstract
Several biological activities depend on iron-sulfur clusters ([Fe-S]). Even though they are well-known in several organisms their function and metabolic pathway were poorly understood in the majority of the organisms. We propose to use the amoeba Dictyostelium discoideum, as a biological model to study the biosynthesis of [Fe-S] at the molecular, cellular and organism levels. First, we have explored the D. discoideum genome looking for genes corresponding to the subunits that constitute the molecular machinery for Fe-S cluster assembly and, based on the structure of the mammalian supercomplex and amino acid conservation profiles, we inferred the full functionality of the amoeba machinery. After that, we expressed the recombinant mature form of D. discoideum frataxin protein (DdFXN), the kinetic activator of this pathway. We characterized the protein and its conformational stability. DdFXN is monomeric and compact. The analysis of the secondary structure content, calculated using the far-UV CD spectra, was compatible with the data expected for the FXN fold, and near-UV CD spectra were compatible with the data corresponding to a folded protein. In addition, Tryptophan fluorescence indicated that the emission occurs from an apolar environment. However, the conformation of DdFXN is significantly less stable than that of the human FXN, (4.0 vs. 9.0 kcal mol-1, respectively). Based on a sequence analysis and structural models of DdFXN, we investigated key residues involved in the interaction of DdFXN with the supercomplex and the effect of point mutations on the energetics of the DdFXN tertiary structure. More than 10 residues involved in Friedreich's Ataxia are conserved between the human and DdFXN forms, and a good correlation between mutational effect on the energetics of both proteins were found, suggesting the existence of similar sequence/function/stability relationships. Finally, we integrated this information in an evolutionary context which highlights particular variation patterns between amoeba and humans that may reflect a functional importance of specific protein positions. Moreover, the complete pathway obtained forms a piece of evidence in favor of the hypothesis of a shared and highly conserved [Fe-S] assembly machinery between Human and D. discoideum.
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Affiliation(s)
- Justo Olmos
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina; (J.O.); (M.F.P.); (A.B.B.d.S.); (L.K.)
| | - María Florencia Pignataro
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina; (J.O.); (M.F.P.); (A.B.B.d.S.); (L.K.)
| | - Ana Belén Benítez dos Santos
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina; (J.O.); (M.F.P.); (A.B.B.d.S.); (L.K.)
| | - Mauro Bringas
- 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 C1428EGA, Argentina;
| | - Sebastián Klinke
- Fundación Instituto Leloir, IIBBA-CONICET, and Plataforma Argentina de Biología Estructural y Metabolómica PLABEM, Av. Patricias Argentinas 435, Buenos Aires C1405BWE, Argentina;
| | - Laura Kamenetzky
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina; (J.O.); (M.F.P.); (A.B.B.d.S.); (L.K.)
- IMPaM, CONICET, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires C1121ABG, Argentina
| | - Francisco Velazquez
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina; (J.O.); (M.F.P.); (A.B.B.d.S.); (L.K.)
- Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN)—(UBA/CONICET), Buenos Aires C1428EGA, Argentina
| | - Javier Santos
- Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina; (J.O.); (M.F.P.); (A.B.B.d.S.); (L.K.)
- Consejo Nacional de Investigaciones Científicas y Técnicas, Rivadavia 1917, Buenos Aires C1033AAJ, Argentina
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires. Intendente Güiraldes 2160, Ciudad Universitaria, Buenos Aires C1428EGA, Argentina
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11
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Nuzhny EP, Abramycheva NY, Nikolaeva NS, Ershova MV, Klyushnikov SA, Illarioshkin SN, Fedotova EY. [Epigenetic regulation of clinical manifestations of Friedreich's disease]. Zh Nevrol Psikhiatr Im S S Korsakova 2020; 120:20-26. [PMID: 32105265 DOI: 10.17116/jnevro202012001120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
AIM To study a methylation profile of FXN gene and its influence on the clinical phenotype of Friedreich's desease (FD). MATERIAL AND METHODS The methylation pattern was analyzed in 17 patients with FD. Forty-five CpG-sites in the promoter region and the region of intron 1 of FXN: before the GAA-expansion (UP-GAA) and after the GAA-expansion (DOWN-GAA), were studied. RESULTS Correlations between the methylation level of CpG-sites in UP-GAA and DOWN-GAA and the number of GAA repeats in both expanded FXN alleles in patients with FD were found. An analysis revealed an earlier onset and a more severe course of FD in cases with hypermethylation of several CpG-sites in the UP-GAA region. The correlation between the methylation pattern and the presence of extraneural manifestations of FD was also revealed. In FD patients with cardiomyopathy, a hypomethylated CpG-site in the promoter region was found. In FD patients with carbohydrate metabolism disorders, two hypomethylated CpG-sites in the DOWN-GAA region were observed. CONCLUSION The results indicate a significant contribution of epigenetic modifications of FXN to the clinical presentation of FA.
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Affiliation(s)
- E P Nuzhny
- Research Center of Neurology, Moscow, Russia
| | | | | | - M V Ershova
- Research Center of Neurology, Moscow, Russia
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12
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González-Lebrero RM, Defelipe L, Modenutti C, Roitberg AE, Batastini NA, Noguera ME, Santos J, Roman EA. Folding and Dynamics Are Strongly pH-Dependent in a Psychrophile Frataxin. J Phys Chem B 2019; 123:7676-7686. [PMID: 31407901 DOI: 10.1021/acs.jpcb.9b05960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Protein dynamics, folding, and thermodynamics represent a central aspect of biophysical chemistry. pH, temperature, and denaturant perturbations inform our understanding of diverse contributors to stability and rates. In this work, we performed a thermodynamic analysis using a combined experimental and computational approach to gain insights into the role of electrostatics in the folding reaction of a psychrophile frataxin variant from Psychromonas ingrahamii. This folding reaction is strongly modulated by pH with a single, narrow, and well-defined transition state with ∼80% compactness, ∼70% electrostatic interactions, and ∼60% hydration shell compared to the native state (αD = 0.82, αH = 0.67, and αΔCp = 0.59). Our results are best explained by a two-proton/two-state model with very different pKa values of the native and denatured states (∼5.5 and ∼8.0, respectively). As a consequence, the stability strongly increases from pH 8.0 to 6.0 (|ΔΔG°| = 5.2 kcal mol-1), mainly because of a decrease in the TΔS°. Variation of ΔH° and ΔS° at pH below 7.0 is dominated by a change in ΔHf⧧ and ΔSf⧧, while at pH above 7.0, it is governed by ΔHu⧧ and ΔSu⧧. Molecular dynamics simulations showed that these pH modulations could be explained by the fluctuations of two regions, rich in electrostatic contacts, whose dynamics are pH-dependent and motions are strongly correlated. Results presented herein contribute to the understanding of the stability and dynamics of this frataxin variant, pointing to an intrinsic feature of the family topology to support different folding mechanisms.
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Affiliation(s)
- Rodolfo M González-Lebrero
- Facultad de Farmacia y Bioquímica, Departamento de Química Biológica , Universidad de Buenos Aires , Buenos Aires C1113AAD , Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas , Instituto de Química y Fisicoquímica Biológicas , Buenos Aires C1113AAD , Argentina
| | | | | | - Adrian E Roitberg
- Department of Chemistry , University of Florida , Gainesville , Florida 32611 , United States
| | - Nicolas A Batastini
- Facultad de Farmacia y Bioquímica, Departamento de Química Biológica , Universidad de Buenos Aires , Buenos Aires C1113AAD , Argentina
| | - Martín E Noguera
- Facultad de Farmacia y Bioquímica, Departamento de Química Biológica , Universidad de Buenos Aires , Buenos Aires C1113AAD , Argentina
| | | | - Ernesto A Roman
- Consejo Nacional de Investigaciones Científicas y Técnicas , Instituto de Química y Fisicoquímica Biológicas , Buenos Aires C1113AAD , Argentina
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13
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Faraj SE, Noguera ME, Delfino JM, Santos J. Global Implications of Local Unfolding Phenomena, Probed by Cysteine Reactivity in Human Frataxin. Sci Rep 2019; 9:1731. [PMID: 30742023 PMCID: PMC6370780 DOI: 10.1038/s41598-019-39429-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 01/18/2019] [Indexed: 12/28/2022] Open
Abstract
Local events that affect specific regions of proteins are of utmost relevance for stability and function. The aim of this study is to quantitatively assess the importance of locally-focused dynamics by means of a simple chemical modification procedure. Taking human Frataxin as a working model, we investigated local fluctuations of the C-terminal region (the last 16 residues of the protein) by means of three L → C replacement mutants: L98C, L200C and L203C. The conformation and thermodynamic stability of each variant was assessed. All the variants exhibited native features and high stabilities: 9.1 (wild type), 8.1 (L198C), 7.0 (L200C) and 10.0 kcal mol-1 (L203C). In addition, kinetic rates of Cys chemical modification by DTNB and DTDPy were measured, conformational dynamics data were extracted and free energy for the local unfolding of the C-terminal region was estimated. The analysis of these results indicates that the conformation of the C-terminal region fluctuates with partial independence from global unfolding events. Additionally, numerical fittings of the kinetic model of the process suggest that the local transition occurs in the seconds to minutes timescale. In fact, standard free energy differences for local unfolding were found to be significantly lower than those of the global unfolding reaction, showing that chemical modification results may not be explained in terms of the global unfolding reaction alone. These results provide unequivocal experimental evidence of local phenomena with global effects and contribute to understanding how global and local stability are linked to protein dynamics.
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Affiliation(s)
- Santiago E Faraj
- Alejandro Paladini Institute of Biological Chemistry and Chemical Physics (UBA-CONICET), Faculty of Pharmacy and Biochemistry, University of Buenos Aires, Junín 956, (C1113AAD), Buenos Aires, Argentina
| | - Martín E Noguera
- Alejandro Paladini Institute of Biological Chemistry and Chemical Physics (UBA-CONICET), Faculty of Pharmacy and Biochemistry, University of Buenos Aires, Junín 956, (C1113AAD), Buenos Aires, Argentina
| | - José María Delfino
- Alejandro Paladini Institute of Biological Chemistry and Chemical Physics (UBA-CONICET), Faculty of Pharmacy and Biochemistry, University of Buenos Aires, Junín 956, (C1113AAD), Buenos Aires, Argentina
| | - Javier Santos
- Alejandro Paladini Institute of Biological Chemistry and Chemical Physics (UBA-CONICET), Faculty of Pharmacy and Biochemistry, University of Buenos Aires, Junín 956, (C1113AAD), Buenos Aires, Argentina. .,Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencia Exactas y Naturales, Universidad de Buenos Aires. Instituto de Biociencias, Biotecnología y Biomedicina (iB3). Intendente Güiraldes 2160 - Ciudad Universitaria, 1428EGA, C.A.B.A., Argentina.
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Castro IH, Pignataro MF, Sewell KE, Espeche LD, Herrera MG, Noguera ME, Dain L, Nadra AD, Aran M, Smal C, Gallo M, Santos J. Frataxin Structure and Function. Subcell Biochem 2019; 93:393-438. [PMID: 31939159 DOI: 10.1007/978-3-030-28151-9_13] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Mammalian frataxin is a small mitochondrial protein involved in iron sulfur cluster assembly. Frataxin deficiency causes the neurodegenerative disease Friedreich's Ataxia. Valuable knowledge has been gained on the structural dynamics of frataxin, metal-ion-protein interactions, as well as on the effect of mutations on protein conformation, stability and internal motions. Additionally, laborious studies concerning the enzymatic reactions involved have allowed for understanding the capability of frataxin to modulate Fe-S cluster assembly function. Remarkably, frataxin biological function depends on its interaction with some proteins to form a supercomplex, among them NFS1 desulfurase and ISCU, the scaffolding protein. By combining multiple experimental tools including high resolution techniques like NMR and X-ray, but also SAXS, crosslinking and mass-spectrometry, it was possible to build a reliable model of the structure of the desulfurase supercomplex NFS1/ACP-ISD11/ISCU/frataxin. In this chapter, we explore these issues showing how the scientific view concerning frataxin structure-function relationships has evolved over the last years.
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Affiliation(s)
- Ignacio Hugo Castro
- Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencia Exactas y Naturales, Instituto de Biociencias, Biotecnología y Biomedicina (iB3), Universidad de Buenos Aires, Intendente Güiraldes 2160-Ciudad Universitaria, 1428EGA, C.A.B.A, Argentina
- Intituto de Química y Fisicoquímica Biológicas, Dr. Alejandro Paladini Universidad de Buenos Aires, CONICET, Junín 956, 1113AAD, C.A.B.A, Argentina
| | - María Florencia Pignataro
- Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencia Exactas y Naturales, Instituto de Biociencias, Biotecnología y Biomedicina (iB3), Universidad de Buenos Aires, Intendente Güiraldes 2160-Ciudad Universitaria, 1428EGA, C.A.B.A, Argentina
- Intituto de Química y Fisicoquímica Biológicas, Dr. Alejandro Paladini Universidad de Buenos Aires, CONICET, Junín 956, 1113AAD, C.A.B.A, Argentina
| | - Karl Ellioth Sewell
- Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencia Exactas y Naturales, Instituto de Biociencias, Biotecnología y Biomedicina (iB3), Universidad de Buenos Aires, Intendente Güiraldes 2160-Ciudad Universitaria, 1428EGA, C.A.B.A, Argentina
- Intituto de Química y Fisicoquímica Biológicas, Dr. Alejandro Paladini Universidad de Buenos Aires, CONICET, Junín 956, 1113AAD, C.A.B.A, Argentina
| | - Lucía Daniela Espeche
- Departamento de Diagnóstico Genético, Centro Nacional de Genética Médica "Dr. Eduardo E. Castilla"-A.N.L.I.S, Av. Las Heras 2670, C1425ASQ, C.A.B.A, Argentina
| | - María Georgina Herrera
- Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencia Exactas y Naturales, Instituto de Biociencias, Biotecnología y Biomedicina (iB3), Universidad de Buenos Aires, Intendente Güiraldes 2160-Ciudad Universitaria, 1428EGA, C.A.B.A, Argentina
| | - Martín Ezequiel Noguera
- Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencia Exactas y Naturales, Instituto de Biociencias, Biotecnología y Biomedicina (iB3), Universidad de Buenos Aires, Intendente Güiraldes 2160-Ciudad Universitaria, 1428EGA, C.A.B.A, Argentina
- Intituto de Química y Fisicoquímica Biológicas, Dr. Alejandro Paladini Universidad de Buenos Aires, CONICET, Junín 956, 1113AAD, C.A.B.A, Argentina
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Roque Sáenz Peña 352, B1876BXD, Bernal, Provincia de Buenos Aires, Argentina
| | - Liliana Dain
- Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencia Exactas y Naturales, Instituto de Biociencias, Biotecnología y Biomedicina (iB3), Universidad de Buenos Aires, Intendente Güiraldes 2160-Ciudad Universitaria, 1428EGA, C.A.B.A, Argentina
- Departamento de Diagnóstico Genético, Centro Nacional de Genética Médica "Dr. Eduardo E. Castilla"-A.N.L.I.S, Av. Las Heras 2670, C1425ASQ, C.A.B.A, Argentina
| | - Alejandro Daniel Nadra
- Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencia Exactas y Naturales, Instituto de Biociencias, Biotecnología y Biomedicina (iB3), Universidad de Buenos Aires, Intendente Güiraldes 2160-Ciudad Universitaria, 1428EGA, C.A.B.A, Argentina
- Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Martín Aran
- Fundación Instituto Leloir E IIBBA-CONICET, Av. Patricias Argentinas 435, C1405BWE, Buenos Aires, Argentina
| | - Clara Smal
- Fundación Instituto Leloir E IIBBA-CONICET, Av. Patricias Argentinas 435, C1405BWE, Buenos Aires, Argentina
| | - Mariana Gallo
- IRBM Science Park S.p.A, Via Pontina km 30,600, 00071, Pomezia, RM, Italy
| | - Javier Santos
- Departamento de Fisiología y Biología Molecular y Celular, Facultad de Ciencia Exactas y Naturales, Instituto de Biociencias, Biotecnología y Biomedicina (iB3), Universidad de Buenos Aires, Intendente Güiraldes 2160-Ciudad Universitaria, 1428EGA, C.A.B.A, Argentina.
- Intituto de Química y Fisicoquímica Biológicas, Dr. Alejandro Paladini Universidad de Buenos Aires, CONICET, Junín 956, 1113AAD, C.A.B.A, Argentina.
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Castro IH, Ferrari A, Herrera MG, Noguera ME, Maso L, Benini M, Rufini A, Testi R, Costantini P, Santos J. Biophysical characterisation of the recombinant human frataxin precursor. FEBS Open Bio 2018; 8:390-405. [PMID: 29511616 PMCID: PMC5832983 DOI: 10.1002/2211-5463.12376] [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: 11/02/2017] [Revised: 12/25/2017] [Accepted: 12/27/2017] [Indexed: 11/10/2022] Open
Abstract
Friedreich's ataxia is a disease caused by a decrease in the levels of expression or loss of functionality of the mitochondrial protein frataxin (FXN). The development of an active and stable recombinant variant of FXN is important for protein replacement therapy. Although valuable data about the mature form FXN81-210 has been collected, not enough information is available about the conformation of the frataxin precursor (FXN1-210). We investigated the conformation, stability and function of a recombinant precursor variant (His6-TAT-FXN1-210), which includes a TAT peptide in the N-terminal region to assist with transport across cell membranes. His6-TAT-FXN1-210 was expressed in Escherichia coli and conditions were found for purifying folded protein free of aggregation, oxidation or degradation, even after freezing and thawing. The protein was found to be stable and monomeric, with the N-terminal stretch (residues 1-89) mostly unstructured and the C-terminal domain properly folded. The experimental data suggest a complex picture for the folding process of full-length frataxin in vitro: the presence of the N-terminal region increased the tendency of FXN to aggregate at high temperatures but this could be avoided by the addition of low concentrations of GdmCl. The purified precursor was translocated through cell membranes. In addition, immune response against His6-TAT-FXN1-210 was measured, suggesting that the C-terminal fragment was not immunogenic at the assayed protein concentrations. Finally, the recognition of recombinant FXN by cellular proteins was studied to evaluate its functionality. In this regard, cysteine desulfurase NFS1/ISD11/ISCU was activated in vitro by His6-TAT-FXN1-210. Moreover, the results showed that His6-TAT-FXN1-210 can be ubiquitinated in vitro by the recently identified frataxin E3 ligase RNF126, in a similar way as the FXN1-210, suggesting that the His6-TAT extension does not interfere with the ubiquitination machinery.
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Affiliation(s)
- Ignacio Hugo Castro
- Institute of Biological Chemistry and Physicochemistry Dr Alejandro Paladini (UBA-CONICET) University of Buenos Aires Argentina
| | - Alejandro Ferrari
- Institute of Biological Chemistry and Physicochemistry Dr Alejandro Paladini (UBA-CONICET) University of Buenos Aires Argentina
| | - María Georgina Herrera
- Institute of Biological Chemistry and Physicochemistry Dr Alejandro Paladini (UBA-CONICET) University of Buenos Aires Argentina
| | - Martín Ezequiel Noguera
- Institute of Biological Chemistry and Physicochemistry Dr Alejandro Paladini (UBA-CONICET) University of Buenos Aires Argentina
| | - Lorenzo Maso
- Department of Biology University of Padova Italy
| | - Monica Benini
- Laboratory of Signal Transduction Department of Biomedicine and Prevention University of Rome ''Tor Vergata'' Italy.,Fratagene Therapeutics srl Rome Italy
| | - Alessandra Rufini
- Laboratory of Signal Transduction Department of Biomedicine and Prevention University of Rome ''Tor Vergata'' Italy.,Fratagene Therapeutics srl Rome Italy
| | - Roberto Testi
- Laboratory of Signal Transduction Department of Biomedicine and Prevention University of Rome ''Tor Vergata'' Italy.,Fratagene Therapeutics srl Rome Italy
| | | | - Javier Santos
- Institute of Biological Chemistry and Physicochemistry Dr Alejandro Paladini (UBA-CONICET) University of Buenos Aires Argentina
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16
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Noguera ME, Aran M, Smal C, Vazquez DS, Herrera MG, Roman EA, Alaimo N, Gallo M, Santos J. Insights on the conformational dynamics of human frataxin through modifications of loop-1. Arch Biochem Biophys 2017; 636:123-137. [PMID: 29097312 DOI: 10.1016/j.abb.2017.10.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 10/20/2017] [Accepted: 10/28/2017] [Indexed: 02/07/2023]
Abstract
Human frataxin (FXN) is a highly conserved mitochondrial protein involved in iron homeostasis and activation of the iron-sulfur cluster assembly. FXN deficiency causes the neurodegenerative disease Friedreich's Ataxia. Here, we investigated the effect of alterations in loop-1, a stretch presumably essential for FXN function, on the conformational stability and dynamics of the native state. We generated four loop-1 variants, carrying substitutions, insertions and deletions. All of them were stable and well-folded proteins. Fast local motions (ps-ns) and slower long-range conformational dynamics (μs-ms) were altered in some mutants as judged by NMR. Particularly, loop-1 modifications impact on the dynamics of a distant region that includes residues from the β-sheet, helix α1 and the C-terminal. Remarkably, all the mutants retain the ability to activate cysteine desulfurase, even when two of them exhibit a strong decrease in iron binding, revealing a differential sensitivity of these functional features to loop-1 perturbation. Consequently, we found that even for a small and relatively rigid protein, engineering a loop segment enables to alter conformational dynamics through a long-range effect, preserving the native-state structure and important aspects of function.
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Affiliation(s)
- Martín E Noguera
- Instituto de Química y Físico-Química Biológicas, University of Buenos Aires, Junín 956, 1113AAD, Buenos Aires, Argentina
| | - Martín Aran
- The Leloir Institute Foundation and IIBBA-CONICET, Av. Patricias Argentinas 435, 1405 Buenos Aires, Argentina
| | - Clara Smal
- The Leloir Institute Foundation and IIBBA-CONICET, Av. Patricias Argentinas 435, 1405 Buenos Aires, Argentina
| | - Diego S Vazquez
- Instituto de Química y Físico-Química Biológicas, University of Buenos Aires, Junín 956, 1113AAD, Buenos Aires, Argentina
| | - María Georgina Herrera
- Instituto de Química y Físico-Química Biológicas, University of Buenos Aires, Junín 956, 1113AAD, Buenos Aires, Argentina
| | - Ernesto A Roman
- Instituto de Química y Físico-Química Biológicas, University of Buenos Aires, Junín 956, 1113AAD, Buenos Aires, Argentina
| | - Nadine Alaimo
- Dipartimento di Scienze e Tecnologie Chimiche, University of Rome "Tor Vergata", Via della Ricerca Scientifica snc, 00133 Roma, Italy
| | - Mariana Gallo
- Dipartimento di Scienze e Tecnologie Chimiche, University of Rome "Tor Vergata", Via della Ricerca Scientifica snc, 00133 Roma, Italy; IRBM Science Park S.p.A., Via Pontina km 30,600., 00071 Pomezia (RM), Italy.
| | - Javier Santos
- Instituto de Química y Físico-Química Biológicas, University of Buenos Aires, Junín 956, 1113AAD, Buenos Aires, Argentina.
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17
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Buchensky C, Sánchez M, Carrillo M, Palacios O, Capdevila M, Domínguez-Vera JM, Busi MV, Atrian S, Pagani MA, Gomez-Casati DF. Identification of two frataxin isoforms in Zea mays: Structural and functional studies. Biochimie 2017; 140:34-47. [PMID: 28630009 DOI: 10.1016/j.biochi.2017.06.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 06/15/2017] [Indexed: 11/19/2022]
Abstract
Frataxin is a ubiquitous protein that plays a role in Fe-S cluster biosynthesis and iron and heme metabolism, although its molecular functions are not entirely clear. In non-photosynthetic eukaryotes, frataxin is encoded by a single gene, and the protein localizes to mitochondria. Here we report the presence of two functional frataxin isoforms in Zea mays, ZmFH-1 and ZmFH-2. We confirmed our previous findings regarding plant frataxins: both proteins have dual localization in mitochondria and chloroplasts. Physiological, biochemical and biophysical studies show some differences in the expression pattern, protection against oxidants and in the aggregation state of both isoforms, suggesting that the two frataxin homologs would play similar but not identical roles in plant cell metabolism. In addition, two specific features of plant frataxins were evidenced: their ability to form dimers and their tendency to undergo conformational change under oxygen exposure.
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Affiliation(s)
- Celeste Buchensky
- CEFOBI - CONICET, Centro de Estudios Fotosintéticos y Bioquímicos - Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina
| | - Manuel Sánchez
- Departamento de Química Inorgánica, Facultad de Ciencias. Instituto de Biotecnología, Universidad de Granada, 18071, Granada, Spain
| | - Martin Carrillo
- CEFOBI - CONICET, Centro de Estudios Fotosintéticos y Bioquímicos - Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina
| | - Oscar Palacios
- Departament de Química, Facultat de Ciènces, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Barcelona, Spain
| | - Mercè Capdevila
- Departament de Química, Facultat de Ciènces, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Barcelona, Spain
| | - Jose M Domínguez-Vera
- Departamento de Química Inorgánica, Facultad de Ciencias. Instituto de Biotecnología, Universidad de Granada, 18071, Granada, Spain
| | - Maria V Busi
- CEFOBI - CONICET, Centro de Estudios Fotosintéticos y Bioquímicos - Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina
| | - Sílvia Atrian
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona, Av. Diagonal 643, 08028, Barcelona, Spain
| | - Maria A Pagani
- CEFOBI - CONICET, Centro de Estudios Fotosintéticos y Bioquímicos - Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina
| | - Diego F Gomez-Casati
- CEFOBI - CONICET, Centro de Estudios Fotosintéticos y Bioquímicos - Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Santa Fe, Argentina.
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18
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Bürk K. Friedreich Ataxia: current status and future prospects. CEREBELLUM & ATAXIAS 2017; 4:4. [PMID: 28405347 PMCID: PMC5383992 DOI: 10.1186/s40673-017-0062-x] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 03/24/2017] [Indexed: 01/23/2023]
Abstract
Friedreich ataxia (FA) represents the most frequent type of inherited ataxia. Most patients carry homozygous GAA expansions in the first intron of the frataxin gene on chromosome 9. Due to epigenetic alterations, frataxin expression is significantly reduced. Frataxin is a mitochondrial protein. Its deficiency leads to mitochondrial iron overload, defective energy supply and generation of reactive oxygen species. This review gives an overview over clinical and genetic aspects of FA and discusses current concepts of frataxin biogenesis and function as well as new therapeutic strategies.
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Affiliation(s)
- Katrin Bürk
- University of Marburg, and Paracelsus-Elena Klinik, Klinikstr. 16, 34128 Kassel, Germany
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19
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Faraj SE, González-Lebrero RM, Roman EA, Santos J. Human Frataxin Folds Via an Intermediate State. Role of the C-Terminal Region. Sci Rep 2016; 6:20782. [PMID: 26856628 PMCID: PMC4746760 DOI: 10.1038/srep20782] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 01/12/2016] [Indexed: 11/30/2022] Open
Abstract
The aim of this study is to investigate the folding reaction of human frataxin, whose deficiency causes the neurodegenerative disease Friedreich's Ataxia (FRDA). The characterization of different conformational states would provide knowledge about how frataxin can be stabilized without altering its functionality. Wild-type human frataxin and a set of mutants, including two highly destabilized FRDA-associated variants were studied by urea-induced folding/unfolding in a rapid mixing device and followed by circular dichroism. The analysis clearly indicates the existence of an intermediate state (I) in the folding route with significant secondary structure content but relatively low compactness, compared with the native ensemble. However, at high NaCl concentrations I-state gains substantial compaction, and the unfolding barrier is strongly affected, revealing the importance of electrostatics in the folding mechanism. The role of the C-terminal region (CTR), the key determinant of frataxin stability, was also studied. Simulations consistently with experiments revealed that this stretch is essentially unstructured, in the most compact transition state ensemble (TSE2). The complete truncation of the CTR drastically destabilizes the native state without altering TSE2. Results presented here shed light on the folding mechanism of frataxin, opening the possibility of mutating it to generate hyperstable variants without altering their folding kinetics.
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Affiliation(s)
- Santiago E. Faraj
- Instituto de Química y Físico-Química Biológicas, Universidad de Buenos Aires, Junín 956, 1113AAD, Buenos Aires, Argentina
| | - Rodolfo M. González-Lebrero
- Instituto de Química y Físico-Química Biológicas, Universidad de Buenos Aires, Junín 956, 1113AAD, Buenos Aires, Argentina
| | - Ernesto A. Roman
- Instituto de Química y Físico-Química Biológicas, Universidad de Buenos Aires, Junín 956, 1113AAD, Buenos Aires, Argentina
| | - Javier Santos
- Instituto de Química y Físico-Química Biológicas, Universidad de Buenos Aires, Junín 956, 1113AAD, Buenos Aires, Argentina
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