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Bonsor M, Ammar O, Schnoegl S, Wanker EE, Silva Ramos E. Polyglutamine disease proteins: Commonalities and differences in interaction profiles and pathological effects. Proteomics 2024; 24:e2300114. [PMID: 38615323 DOI: 10.1002/pmic.202300114] [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: 11/30/2023] [Revised: 03/25/2024] [Accepted: 03/27/2024] [Indexed: 04/16/2024]
Abstract
Currently, nine polyglutamine (polyQ) expansion diseases are known. They include spinocerebellar ataxias (SCA1, 2, 3, 6, 7, 17), spinal and bulbar muscular atrophy (SBMA), dentatorubral-pallidoluysian atrophy (DRPLA), and Huntington's disease (HD). At the root of these neurodegenerative diseases are trinucleotide repeat mutations in coding regions of different genes, which lead to the production of proteins with elongated polyQ tracts. While the causative proteins differ in structure and molecular mass, the expanded polyQ domains drive pathogenesis in all these diseases. PolyQ tracts mediate the association of proteins leading to the formation of protein complexes involved in gene expression regulation, RNA processing, membrane trafficking, and signal transduction. In this review, we discuss commonalities and differences among the nine polyQ proteins focusing on their structure and function as well as the pathological features of the respective diseases. We present insights from AlphaFold-predicted structural models and discuss the biological roles of polyQ-containing proteins. Lastly, we explore reported protein-protein interaction networks to highlight shared protein interactions and their potential relevance in disease development.
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Affiliation(s)
- Megan Bonsor
- Department of Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Orchid Ammar
- Department of Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Sigrid Schnoegl
- Department of Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Erich E Wanker
- Department of Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Eduardo Silva Ramos
- Department of Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
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2
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Zhang Z, Gehin C, Abriata LA, Dal Peraro M, Lashuel H. Differential Effects of Post-translational Modifications on the Membrane Interaction of Huntingtin Protein. ACS Chem Neurosci 2024. [PMID: 38752226 DOI: 10.1021/acschemneuro.4c00091] [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: 05/25/2024] Open
Abstract
Huntington's disease is a neurodegenerative disorder caused by an expanded polyglutamine stretch near the N-terminus of the huntingtin (HTT) protein, rendering the protein more prone to aggregate. The first 17 residues in HTT (Nt17) interact with lipid membranes and harbor multiple post-translational modifications (PTMs) that can modulate HTT conformation and aggregation. In this study, we used a combination of biophysical studies and molecular simulations to investigate the effect of PTMs on the helicity of Nt17 in the presence of various lipid membranes. We demonstrate that anionic lipids such as PI4P, PI(4,5)P2, and GM1 significantly enhance the helical structure of unmodified Nt17. This effect is attenuated by single acetylation events at K6, K9, or K15, whereas tri-acetylation at these sites abolishes Nt17-membrane interaction. Similarly, single phosphorylation at S13 and S16 decreased but did not abolish the POPG and PIP2-induced helicity, while dual phosphorylation at these sites markedly diminished Nt17 helicity, regardless of lipid composition. The helicity of Nt17 with phosphorylation at T3 is insensitive to the membrane environment. Oxidation at M8 variably affects membrane-induced helicity, highlighting a lipid-dependent modulation of the Nt17 structure. Altogether, our findings reveal differential effects of PTMs and crosstalks between PTMs on membrane interaction and conformation of HTT. Intriguingly, the effects of phosphorylation at T3 or single acetylation at K6, K9, and K15 on Nt17 conformation in the presence of certain membranes do not mirror that observed in the absence of membranes. Our studies provide novel insights into the complex relationship between Nt17 structure, PTMs, and membrane binding.
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Affiliation(s)
- Zhidian Zhang
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
- Laboratory for Biomolecular Modeling, School of Life Sciences, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Charlotte Gehin
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Luciano A Abriata
- Laboratory for Biomolecular Modeling, School of Life Sciences, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Matteo Dal Peraro
- Laboratory for Biomolecular Modeling, School of Life Sciences, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Hilal Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
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3
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Antón R, Treviño MÁ, Pantoja-Uceda D, Félix S, Babu M, Cabrita EJ, Zweckstetter M, Tinnefeld P, Vera AM, Oroz J. Alternative low-populated conformations prompt phase transitions in polyalanine repeat expansions. Nat Commun 2024; 15:1925. [PMID: 38431667 PMCID: PMC10908835 DOI: 10.1038/s41467-024-46236-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 02/19/2024] [Indexed: 03/05/2024] Open
Abstract
Abnormal trinucleotide repeat expansions alter protein conformation causing malfunction and contribute to a significant number of incurable human diseases. Scarce structural insights available on disease-related homorepeat expansions hinder the design of effective therapeutics. Here, we present the dynamic structure of human PHOX2B C-terminal fragment, which contains the longest polyalanine segment known in mammals. The major α-helical conformation of the polyalanine tract is solely extended by polyalanine expansions in PHOX2B, which are responsible for most congenital central hypoventilation syndrome cases. However, polyalanine expansions in PHOX2B additionally promote nascent homorepeat conformations that trigger length-dependent phase transitions into solid condensates that capture wild-type PHOX2B. Remarkably, HSP70 and HSP90 chaperones specifically seize PHOX2B alternative conformations preventing phase transitions. The precise observation of emerging polymorphs in expanded PHOX2B postulates unbalanced phase transitions as distinct pathophysiological mechanisms in homorepeat expansion diseases, paving the way towards the search of therapeutics modulating biomolecular condensates in central hypoventilation syndrome.
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Affiliation(s)
- Rosa Antón
- Instituto de Química Física Blas Cabrera (IQF), CSIC, E-28006, Madrid, Spain
| | - Miguel Á Treviño
- Instituto de Química Física Blas Cabrera (IQF), CSIC, E-28006, Madrid, Spain
| | - David Pantoja-Uceda
- Instituto de Química Física Blas Cabrera (IQF), CSIC, E-28006, Madrid, Spain
| | - Sara Félix
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516, Caparica, Portugal
- UCIBIO, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516, Caparica, Portugal
| | - María Babu
- German Center for Neurodegenerative Diseases (DZNE), 37075, Göttingen, Germany
| | - Eurico J Cabrita
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516, Caparica, Portugal
- UCIBIO, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, 2819-516, Caparica, Portugal
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), 37075, Göttingen, Germany
- Department for NMR-based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, 37077, Göttingen, Germany
| | - Philip Tinnefeld
- Department of Chemistry and Center for NanoScience, Ludwig-Maximilians-Universität München, München, 81377, Germany
| | - Andrés M Vera
- Department of Chemistry and Center for NanoScience, Ludwig-Maximilians-Universität München, München, 81377, Germany
| | - Javier Oroz
- Instituto de Química Física Blas Cabrera (IQF), CSIC, E-28006, Madrid, Spain.
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Tsai TY, Chen CY, Lin TW, Lin TC, Chiu FL, Shih O, Chang MY, Lin YC, Su AC, Chen CM, Jeng US, Kuo HC, Chang CF, Chen YR. Amyloid modifier SERF1a interacts with polyQ-expanded huntingtin-exon 1 via helical interactions and exacerbates polyQ-induced toxicity. Commun Biol 2023; 6:767. [PMID: 37479809 PMCID: PMC10361993 DOI: 10.1038/s42003-023-05142-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 07/13/2023] [Indexed: 07/23/2023] Open
Abstract
Abnormal polyglutamine (polyQ) expansion and fibrillization occur in Huntington's disease (HD). Amyloid modifier SERF enhances amyloid formation, but the underlying mechanism is not revealed. Here, the fibrillization and toxicity effect of SERF1a on Htt-exon1 are examined. SERF1a enhances the fibrillization of and interacts with mutant thioredoxin (Trx)-fused Httex1. NMR studies with Htt peptides show that TrxHttex1-39Q interacts with the helical regions in SERF1a and SERF1a preferentially interacts with the N-terminal 17 residues of Htt. Time-course analysis shows that SERF1a induces mutant TrxHttex1 to a single conformation enriched of β-sheet. Co-expression of SERF1a and Httex1-polyQ in neuroblastoma and lentiviral infection of SERF1a in HD-induced polypotent stem cell (iPSC)-derived neurons demonstrates the detrimental effect of SERF1a in HD. Higher level of SERF1a transcript or protein is detected in HD iPSC, transgenic mice, and HD plasma. Overall, this study provides molecular mechanism for SERF1a and mutant Httex1 to facilitate therapeutic development for HD.
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Affiliation(s)
- Tien-Ying Tsai
- Genomics Research Center, Academia Sinica, 128, Academia Rd., Sec. 2, Nankang District, Taipei, 115, Taiwan
- Chemical Biology and Molecular Biophysics Program, Taiwan International Graduate Program, Institute of Biological Chemistry, Academia Sinica, 128, Academia Road, Sec. 2. Nankang, Taipei, 115, Taiwan
- Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Chun-Yu Chen
- Genomics Research Center, Academia Sinica, 128, Academia Rd., Sec. 2, Nankang District, Taipei, 115, Taiwan
| | - Tien-Wei Lin
- Genomics Research Center, Academia Sinica, 128, Academia Rd., Sec. 2, Nankang District, Taipei, 115, Taiwan
| | - Tien-Chang Lin
- National Synchrotron Radiation Research Center, Hsinchu, 300, Taiwan
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, 300, Taiwan
| | - Feng-Lan Chiu
- Institute of Cellular and Organismic Biology, Academia Sinica, 128, Academia Rd., Sec. 2, Nankang District, Taipei, 115, Taiwan
| | - Orion Shih
- National Synchrotron Radiation Research Center, Hsinchu, 300, Taiwan
| | - Ming-Yun Chang
- Genomics Research Center, Academia Sinica, 128, Academia Rd., Sec. 2, Nankang District, Taipei, 115, Taiwan
- Taiwan International Graduate Program in Interdisciplinary Neuroscience, National Yang Ming Chiao Tung University and Academia Sinica, Taipei, Taiwan
| | - Yu-Chun Lin
- Genomics Research Center, Academia Sinica, 128, Academia Rd., Sec. 2, Nankang District, Taipei, 115, Taiwan
| | - An-Chung Su
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, 300, Taiwan
| | - Chiung-Mei Chen
- Department of Neurology, Linkou Chang Gung Memorial Hospital and College of Medicine, Chang Gung University, Taoyuan, 333, Taiwan
| | - U-Ser Jeng
- National Synchrotron Radiation Research Center, Hsinchu, 300, Taiwan
- Department of Chemical Engineering, National Tsing Hua University, Hsinchu, 300, Taiwan
| | - Hung-Chih Kuo
- Institute of Cellular and Organismic Biology, Academia Sinica, 128, Academia Rd., Sec. 2, Nankang District, Taipei, 115, Taiwan
| | - Chi-Fon Chang
- Genomics Research Center, Academia Sinica, 128, Academia Rd., Sec. 2, Nankang District, Taipei, 115, Taiwan
| | - Yun-Ru Chen
- Genomics Research Center, Academia Sinica, 128, Academia Rd., Sec. 2, Nankang District, Taipei, 115, Taiwan.
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5
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Barbosa Pereira PJ, Manso JA, Macedo-Ribeiro S. The structural plasticity of polyglutamine repeats. Curr Opin Struct Biol 2023; 80:102607. [PMID: 37178477 DOI: 10.1016/j.sbi.2023.102607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 04/11/2023] [Accepted: 04/12/2023] [Indexed: 05/15/2023]
Abstract
From yeast to humans, polyglutamine (polyQ) repeat tracts are found frequently in the proteome and are particularly prominent in the activation domains of transcription factors. PolyQ is a polymorphic motif that modulates functional protein-protein interactions and aberrant self-assembly. Expansion of the polyQ repeated sequences beyond critical physiological repeat length thresholds triggers self-assembly and is linked to severe pathological implications. This review provides an overview of the current knowledge on the structures of polyQ tracts in the soluble and aggregated states and discusses the influence of neighboring regions on polyQ secondary structure, aggregation, and fibril morphologies. The influence of the genetic context of the polyQ-encoding trinucleotides is briefly discussed as a challenge for future endeavors in this field.
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Affiliation(s)
- Pedro José Barbosa Pereira
- IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal.
| | - José A Manso
- IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
| | - Sandra Macedo-Ribeiro
- IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135, Porto, Portugal
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6
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Elena-Real CA, Urbanek A, Lund XL, Morató A, Sagar A, Fournet A, Estaña A, Bellande T, Allemand F, Cortés J, Sibille N, Melki R, Bernadó P. Multi-site-specific isotopic labeling accelerates high-resolution structural investigations of pathogenic huntingtin exon-1. Structure 2023:S0969-2126(23)00126-0. [PMID: 37119819 DOI: 10.1016/j.str.2023.04.003] [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: 02/02/2023] [Revised: 03/10/2023] [Accepted: 04/04/2023] [Indexed: 05/01/2023]
Abstract
Huntington's disease neurodegeneration occurs when the number of consecutive glutamines in the huntingtin exon-1 (HTTExon1) exceeds a pathological threshold of 35. The sequence homogeneity of HTTExon1 reduces the signal dispersion in NMR spectra, hampering its structural characterization. By simultaneously introducing three isotopically labeled glutamines in a site-specific manner in multiple concatenated samples, 18 glutamines of a pathogenic HTTExon1 with 36 glutamines were unambiguously assigned. Chemical shift analyses indicate the α-helical persistence in the homorepeat and the absence of an emerging toxic conformation around the pathological threshold. Using the same type of samples, the recognition mechanism of Hsc70 molecular chaperone has been investigated, indicating that it binds to the N17 region of HTTExon1, inducing the partial unfolding of the poly-Q. The proposed strategy facilitates high-resolution structural and functional studies in low-complexity regions.
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Affiliation(s)
- Carlos A Elena-Real
- Centre de Biologie Structurale (CBS), Université de Montpellier, INSERM, CNRS, 29, rue de Navacelles, 34090 Montpellier, France
| | - Annika Urbanek
- Centre de Biologie Structurale (CBS), Université de Montpellier, INSERM, CNRS, 29, rue de Navacelles, 34090 Montpellier, France
| | - Xamuel L Lund
- Centre de Biologie Structurale (CBS), Université de Montpellier, INSERM, CNRS, 29, rue de Navacelles, 34090 Montpellier, France; Institut Laue Langevin, 38000 Grenoble, France
| | - Anna Morató
- Centre de Biologie Structurale (CBS), Université de Montpellier, INSERM, CNRS, 29, rue de Navacelles, 34090 Montpellier, France
| | - Amin Sagar
- Centre de Biologie Structurale (CBS), Université de Montpellier, INSERM, CNRS, 29, rue de Navacelles, 34090 Montpellier, France
| | - Aurélie Fournet
- Centre de Biologie Structurale (CBS), Université de Montpellier, INSERM, CNRS, 29, rue de Navacelles, 34090 Montpellier, France
| | - Alejandro Estaña
- Centre de Biologie Structurale (CBS), Université de Montpellier, INSERM, CNRS, 29, rue de Navacelles, 34090 Montpellier, France; LAAS-CNRS, Université de Toulouse, CNRS, 31400, Toulouse, France
| | - Tracy Bellande
- Institut François Jacob, Molecular Imaging Center (MIRCen), Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA) and Laboratory of Neurodegenerative Diseases, Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay, CEA-Fontenay-aux-Roses Bâtiment 61, 18, route du Panorama, 92265 Fontenay-aux-Rses cedex, France
| | - Frédéric Allemand
- Centre de Biologie Structurale (CBS), Université de Montpellier, INSERM, CNRS, 29, rue de Navacelles, 34090 Montpellier, France
| | - Juan Cortés
- LAAS-CNRS, Université de Toulouse, CNRS, 31400, Toulouse, France
| | - Nathalie Sibille
- Centre de Biologie Structurale (CBS), Université de Montpellier, INSERM, CNRS, 29, rue de Navacelles, 34090 Montpellier, France
| | - Ronald Melki
- Institut François Jacob, Molecular Imaging Center (MIRCen), Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA) and Laboratory of Neurodegenerative Diseases, Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay, CEA-Fontenay-aux-Roses Bâtiment 61, 18, route du Panorama, 92265 Fontenay-aux-Rses cedex, France
| | - Pau Bernadó
- Centre de Biologie Structurale (CBS), Université de Montpellier, INSERM, CNRS, 29, rue de Navacelles, 34090 Montpellier, France.
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7
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Elena-Real CA, Sagar A, Urbanek A, Popovic M, Morató A, Estaña A, Fournet A, Doucet C, Lund XL, Shi ZD, Costa L, Thureau A, Allemand F, Swenson RE, Milhiet PE, Crehuet R, Barducci A, Cortés J, Sinnaeve D, Sibille N, Bernadó P. The structure of pathogenic huntingtin exon 1 defines the bases of its aggregation propensity. Nat Struct Mol Biol 2023; 30:309-320. [PMID: 36864173 DOI: 10.1038/s41594-023-00920-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 01/05/2023] [Indexed: 03/04/2023]
Abstract
Huntington's disease is a neurodegenerative disorder caused by a CAG expansion in the first exon of the HTT gene, resulting in an extended polyglutamine (poly-Q) tract in huntingtin (httex1). The structural changes occurring to the poly-Q when increasing its length remain poorly understood due to its intrinsic flexibility and the strong compositional bias. The systematic application of site-specific isotopic labeling has enabled residue-specific NMR investigations of the poly-Q tract of pathogenic httex1 variants with 46 and 66 consecutive glutamines. Integrative data analysis reveals that the poly-Q tract adopts long α-helical conformations propagated and stabilized by glutamine side chain to backbone hydrogen bonds. We show that α-helical stability is a stronger signature in defining aggregation kinetics and the structure of the resulting fibrils than the number of glutamines. Our observations provide a structural perspective of the pathogenicity of expanded httex1 and pave the way to a deeper understanding of poly-Q-related diseases.
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Affiliation(s)
- Carlos A Elena-Real
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
| | - Amin Sagar
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
| | - Annika Urbanek
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
| | - Matija Popovic
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
| | - Anna Morató
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
| | - Alejandro Estaña
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
- LAAS-CNRS, University of Toulouse, CNRS, Toulouse, France
| | - Aurélie Fournet
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
| | - Christine Doucet
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
| | - Xamuel L Lund
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
- Institute of Laue Langevin, Grenoble, France
| | - Zhen-Dan Shi
- The Chemistry and Synthesis Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Rockville, MD, USA
| | - Luca Costa
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
| | | | - Frédéric Allemand
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
| | - Rolf E Swenson
- The Chemistry and Synthesis Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Rockville, MD, USA
| | | | - Ramon Crehuet
- Institute for Advanced Chemistry of Catalonia (IQAC), CSIC, Barcelona, Spain
| | - Alessandro Barducci
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
| | - Juan Cortés
- LAAS-CNRS, University of Toulouse, CNRS, Toulouse, France
| | - Davy Sinnaeve
- Univ. Lille, INSERM, CHU Lille, Institut Pasteur de Lille, U1167 - RID-AGE - Risk Factors and Molecular Determinants of Aging-Related Diseases, Lille, France
- CNRS, EMR9002, Integrative Structural Biology, Lille, France
| | - Nathalie Sibille
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France
| | - Pau Bernadó
- Centre for Structural Biology, University of Montpellier, INSERM, CNRS, Montpellier, France.
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8
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Khaled M, Strodel B, Sayyed-Ahmad A. Comparative molecular dynamics simulations of pathogenic and non-pathogenic huntingtin protein monomers and dimers. Front Mol Biosci 2023; 10:1143353. [PMID: 37101557 PMCID: PMC10123271 DOI: 10.3389/fmolb.2023.1143353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 03/29/2023] [Indexed: 04/28/2023] Open
Abstract
Polyglutamine expansion at the N-terminus of the huntingtin protein exon 1 (Htt-ex1) is closely associated with a number of neurodegenerative diseases, which result from the aggregation of the increased polyQ repeat. However, the underlying structures and aggregation mechanism are still poorly understood. We performed microsecond-long all-atom molecular dynamics simulations to study the folding and dimerization of Htt-ex1 (about 100 residues) with non-pathogenic and pathogenic polyQ lengths, and uncovered substantial differences. The non-pathogenic monomer adopts a long α-helix that includes most of the polyQ residues, which forms the interaction interface for dimerization, and a PPII-turn-PPII motif in the proline-rich region. In the pathogenic monomer, the polyQ region is disordered, leading to compact structures with many intra-protein interactions and the formation of short β-sheets. Dimerization can proceed via different modes, where those involving the N-terminal headpiece bury more hydrophobic residues and are thus more stable. Moreover, in the pathogenic Htt-ex1 dimers the proline-rich region interacts with the polyQ region, which slows the formation of β-sheets.
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Affiliation(s)
- Mohammed Khaled
- Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich, Jülich, Germany
| | - Birgit Strodel
- Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich, Jülich, Germany
- Institute of Theoretical and Computational Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- *Correspondence: Birgit Strodel, ; Abdallah Sayyed-Ahmad,
| | - Abdallah Sayyed-Ahmad
- Department of Physics, Birzeit University, Birzeit, Palestine
- *Correspondence: Birgit Strodel, ; Abdallah Sayyed-Ahmad,
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9
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Sap KA, Geijtenbeek KW, Schipper-Krom S, Guler AT, Reits EA. Ubiquitin-modifying enzymes in Huntington's disease. Front Mol Biosci 2023; 10:1107323. [PMID: 36926679 PMCID: PMC10013475 DOI: 10.3389/fmolb.2023.1107323] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 01/16/2023] [Indexed: 02/10/2023] Open
Abstract
Huntington's disease (HD) is a neurodegenerative disorder caused by a CAG repeat expansion in the N-terminus of the HTT gene. The CAG repeat expansion translates into a polyglutamine expansion in the mutant HTT (mHTT) protein, resulting in intracellular aggregation and neurotoxicity. Lowering the mHTT protein by reducing synthesis or improving degradation would delay or prevent the onset of HD, and the ubiquitin-proteasome system (UPS) could be an important pathway to clear the mHTT proteins prior to aggregation. The UPS is not impaired in HD, and proteasomes can degrade mHTT entirely when HTT is targeted for degradation. However, the mHTT protein is differently ubiquitinated when compared to wild-type HTT (wtHTT), suggesting that the polyQ expansion affects interaction with (de) ubiquitinating enzymes and subsequent targeting for degradation. The soluble mHTT protein is associated with several ubiquitin-modifying enzymes, and various ubiquitin-modifying enzymes have been identified that are linked to Huntington's disease, either by improving mHTT turnover or affecting overall homeostasis. Here we describe their potential mechanism of action toward improved mHTT targeting towards the proteostasis machinery.
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Affiliation(s)
- Karen A Sap
- Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Karlijne W Geijtenbeek
- Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Sabine Schipper-Krom
- Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Arzu Tugce Guler
- Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Eric A Reits
- Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
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10
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Escobedo A, Piccirillo J, Aranda J, Diercks T, Mateos B, Garcia-Cabau C, Sánchez-Navarro M, Topal B, Biesaga M, Staby L, Kragelund BB, García J, Millet O, Orozco M, Coles M, Crehuet R, Salvatella X. A glutamine-based single α-helix scaffold to target globular proteins. Nat Commun 2022; 13:7073. [PMID: 36400768 PMCID: PMC9674830 DOI: 10.1038/s41467-022-34793-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 11/04/2022] [Indexed: 11/19/2022] Open
Abstract
The binding of intrinsically disordered proteins to globular ones can require the folding of motifs into α-helices. These interactions offer opportunities for therapeutic intervention but their modulation with small molecules is challenging because they bury large surfaces. Linear peptides that display the residues that are key for binding can be targeted to globular proteins when they form stable helices, which in most cases requires their chemical modification. Here we present rules to design peptides that fold into single α-helices by instead concatenating glutamine side chain to main chain hydrogen bonds recently discovered in polyglutamine helices. The resulting peptides are uncharged, contain only natural amino acids, and their sequences can be optimized to interact with specific targets. Our results provide design rules to obtain single α-helices for a wide range of applications in protein engineering and drug design.
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Affiliation(s)
- Albert Escobedo
- grid.473715.30000 0004 6475 7299Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain ,grid.473715.30000 0004 6475 7299Present Address: Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Jonathan Piccirillo
- grid.473715.30000 0004 6475 7299Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain ,grid.428469.50000 0004 1794 1018Present Address: Department of Macromolecular Structures, Centro Nacional de Biotecnología (CNB-CSIC), Madrid, Spain
| | - Juan Aranda
- grid.473715.30000 0004 6475 7299Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Tammo Diercks
- grid.420161.0CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Science and Technology Park, 48160 Derio, Spain
| | - Borja Mateos
- grid.473715.30000 0004 6475 7299Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Carla Garcia-Cabau
- grid.473715.30000 0004 6475 7299Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Macarena Sánchez-Navarro
- Department of Molecular Biology, Instituto de Parasitología y Biomedicina López Neyra (IPBLN-CSIC), Armilla, Granada Spain
| | - Busra Topal
- grid.473715.30000 0004 6475 7299Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Mateusz Biesaga
- grid.473715.30000 0004 6475 7299Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Lasse Staby
- grid.5254.60000 0001 0674 042XREPIN and Structural Biology and NMR Laboratory, The Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaloes Vej 5, DK-2200 Copenhagen N, Denmark
| | - Birthe B. Kragelund
- grid.5254.60000 0001 0674 042XREPIN and Structural Biology and NMR Laboratory, The Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaloes Vej 5, DK-2200 Copenhagen N, Denmark
| | - Jesús García
- grid.473715.30000 0004 6475 7299Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Oscar Millet
- grid.420161.0CIC bioGUNE, Basque Research and Technology Alliance (BRTA), Bizkaia Science and Technology Park, 48160 Derio, Spain
| | - Modesto Orozco
- grid.473715.30000 0004 6475 7299Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain ,grid.5841.80000 0004 1937 0247Department of Biochemistry and Biomedicine, University of Barcelona, Avinguda Diagonal 645, 08028 Barcelona, Spain
| | - Murray Coles
- grid.419580.10000 0001 0942 1125Department of Protein Evolution, Max Planck Institute for Biology, Max-Planck-Ring 5, 72076 Tubingen, Germany
| | - Ramon Crehuet
- grid.4711.30000 0001 2183 4846Institute for Advanced Chemistry of Catalonia (IQAC), CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
| | - Xavier Salvatella
- grid.473715.30000 0004 6475 7299Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028 Barcelona, Spain ,grid.425902.80000 0000 9601 989XICREA, Passeig Lluís Companys 23, 08010 Barcelona, Spain
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11
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Zhang L, Kang H, Perez-Aguilar JM, Zhou R. Possible Co-Evolution of Polyglutamine and Polyproline in Huntingtin Protein: Proline-Rich Domain as Transient Folding Chaperone. J Phys Chem Lett 2022; 13:6331-6341. [PMID: 35796410 DOI: 10.1021/acs.jpclett.2c01184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Huntington's disease is an inherited neurodegenerative disorder caused by the overduplication of CAG repeats in the Huntingtin gene. Recent findings revealed that among the orthologs, the expansion of CAG repeats (polyQ) in the Huntingtin gene occurs in tandem with the duplication of CCG repeats (polyP). However, the molecular mechanism of this possible co-evolution remains unknown. We examined the structures of Huntingtin exon 1 (HttEx1) from six species along with five designed mutants. We found that the polyP segments "chaperone" the rest of the HttEx1 by forming ad hoc polyP binding grooves. Such a process elongates the otherwise poorly solvated polyQ domain, while modulating its secondary structure propensity from β-strands to α-helices. This chaperoning effect is achieved mostly through transient hydrogen bond interactions between polyP and the rest of HttEx1, resulting in a striking golden ratio of ∼2:1 between the chain lengths of polyQ and polyP.
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Affiliation(s)
- Leili Zhang
- Computational Biology Center, IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598, United States
| | - Hongsuk Kang
- Computational Biology Center, IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598, United States
| | - Jose Manuel Perez-Aguilar
- School of Chemical Sciences, Meritorious Autonomous University of Puebla (BUAP), University City, Puebla 72570, Mexico
| | - Ruhong Zhou
- Computational Biology Center, IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598, United States
- Institute of Quantitative Biology, College of Life Sciences, Zhejiang University, Hangzhou 310027, China
- Department of Chemistry, Columbia University, New York, New York 10027, United States
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12
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Maity S, Komal P, Kumar V, Saxena A, Tungekar A, Chandrasekar V. Impact of ER Stress and ER-Mitochondrial Crosstalk in Huntington's Disease. Int J Mol Sci 2022; 23:780. [PMID: 35054963 PMCID: PMC8775980 DOI: 10.3390/ijms23020780] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/30/2021] [Accepted: 01/03/2022] [Indexed: 02/07/2023] Open
Abstract
Accumulation of misfolded proteins is a common phenomenon of several neurodegenerative diseases. The misfolding of proteins due to abnormal polyglutamine (PolyQ) expansions are linked to the development of PolyQ diseases including Huntington's disease (HD). Though the genetic basis of PolyQ repeats in HD remains prominent, the primary molecular basis mediated by PolyQ toxicity remains elusive. Accumulation of misfolded proteins in the ER or disruption of ER homeostasis causes ER stress and activates an evolutionarily conserved pathway called Unfolded protein response (UPR). Protein homeostasis disruption at organelle level involving UPR or ER stress response pathways are found to be linked to HD. Due to dynamic intricate connections between ER and mitochondria, proteins at ER-mitochondria contact sites (mitochondria associated ER membranes or MAMs) play a significant role in HD development. The current review aims at highlighting the most updated information about different UPR pathways and their involvement in HD disease progression. Moreover, the role of MAMs in HD progression has also been discussed. In the end, the review has focused on the therapeutic interventions responsible for ameliorating diseased states via modulating either ER stress response proteins or modulating the expression of ER-mitochondrial contact proteins.
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Affiliation(s)
- Shuvadeep Maity
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS)-Pilani (Hyderabad Campus), Shameerpet-Mandal, Hyderabad 500078, Telangana, India; (P.K.); (V.K.); (A.S.); (A.T.); (V.C.)
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13
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Pigazzini ML, Lawrenz M, Margineanu A, Kaminski Schierle GS, Kirstein J. An Expanded Polyproline Domain Maintains Mutant Huntingtin Soluble in vivo and During Aging. Front Mol Neurosci 2021; 14:721749. [PMID: 34720872 PMCID: PMC8554126 DOI: 10.3389/fnmol.2021.721749] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 08/30/2021] [Indexed: 02/02/2023] Open
Abstract
Huntington's disease is a dominantly inherited neurodegenerative disorder caused by the expansion of a CAG repeat, encoding for the amino acid glutamine (Q), present in the first exon of the protein huntingtin. Over the threshold of Q39 HTT exon 1 (HTTEx1) tends to misfold and aggregate into large intracellular structures, but whether these end-stage aggregates or their on-pathway intermediates are responsible for cytotoxicity is still debated. HTTEx1 can be separated into three domains: an N-terminal 17 amino acid region, the polyglutamine (polyQ) expansion and a C-terminal proline rich domain (PRD). Alongside the expanded polyQ, these flanking domains influence the aggregation propensity of HTTEx1: with the N17 initiating and promoting aggregation, and the PRD modulating it. In this study we focus on the first 11 amino acids of the PRD, a stretch of pure prolines, which are an evolutionary recent addition to the expanding polyQ region. We hypothesize that this proline region is expanding alongside the polyQ to counteract its ability to misfold and cause toxicity, and that expanding this proline region would be overall beneficial. We generated HTTEx1 mutants lacking both flanking domains singularly, missing the first 11 prolines of the PRD, or with this stretch of prolines expanded. We then followed their aggregation landscape in vitro with a battery of biochemical assays, and in vivo in novel models of C. elegans expressing the HTTEx1 mutants pan-neuronally. Employing fluorescence lifetime imaging we could observe the aggregation propensity of all HTTEx1 mutants during aging and correlate this with toxicity via various phenotypic assays. We found that the presence of an expanded proline stretch is beneficial in maintaining HTTEx1 soluble over time, regardless of polyQ length. However, the expanded prolines were only advantageous in promoting the survival and fitness of an organism carrying a pathogenic stretch of Q48 but were extremely deleterious to the nematode expressing a physiological stretch of Q23. Our results reveal the unique importance of the prolines which have and still are evolving alongside expanding glutamines to promote the function of HTTEx1 and avoid pathology.
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Affiliation(s)
- Maria Lucia Pigazzini
- Department of Molecular Physiology and Cell Biology, Leibniz Research Institute for Molecular Pharmacology in the Forschungsverbund Berlin e.V. (FMP), Berlin, Germany
- NeuroCure Cluster of Excellence, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Mandy Lawrenz
- Department of Molecular Physiology and Cell Biology, Leibniz Research Institute for Molecular Pharmacology in the Forschungsverbund Berlin e.V. (FMP), Berlin, Germany
| | - Anca Margineanu
- Advanced Light Microscopy, Max-Delbrück Centrum for Molecular Medicine (MDC), Berlin, Germany
| | - Gabriele S. Kaminski Schierle
- Molecular Neuroscience Group, Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, United Kingdom
| | - Janine Kirstein
- Department of Molecular Physiology and Cell Biology, Leibniz Research Institute for Molecular Pharmacology in the Forschungsverbund Berlin e.V. (FMP), Berlin, Germany
- Department of Cell Biology, University of Bremen, Bremen, Germany
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14
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Mier P, Paladin L, Tamana S, Petrosian S, Hajdu-Soltész B, Urbanek A, Gruca A, Plewczynski D, Grynberg M, Bernadó P, Gáspári Z, Ouzounis CA, Promponas VJ, Kajava AV, Hancock JM, Tosatto SCE, Dosztanyi Z, Andrade-Navarro MA. Disentangling the complexity of low complexity proteins. Brief Bioinform 2021; 21:458-472. [PMID: 30698641 PMCID: PMC7299295 DOI: 10.1093/bib/bbz007] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/19/2018] [Accepted: 01/07/2019] [Indexed: 12/31/2022] Open
Abstract
There are multiple definitions for low complexity regions (LCRs) in protein sequences, with all of them broadly considering LCRs as regions with fewer amino acid types compared to an average composition. Following this view, LCRs can also be defined as regions showing composition bias. In this critical review, we focus on the definition of sequence complexity of LCRs and their connection with structure. We present statistics and methodological approaches that measure low complexity (LC) and related sequence properties. Composition bias is often associated with LC and disorder, but repeats, while compositionally biased, might also induce ordered structures. We illustrate this dichotomy, and more generally the overlaps between different properties related to LCRs, using examples. We argue that statistical measures alone cannot capture all structural aspects of LCRs and recommend the combined usage of a variety of predictive tools and measurements. While the methodologies available to study LCRs are already very advanced, we foresee that a more comprehensive annotation of sequences in the databases will enable the improvement of predictions and a better understanding of the evolution and the connection between structure and function of LCRs. This will require the use of standards for the generation and exchange of data describing all aspects of LCRs. Short abstract There are multiple definitions for low complexity regions (LCRs) in protein sequences. In this critical review, we focus on the definition of sequence complexity of LCRs and their connection with structure. We present statistics and methodological approaches that measure low complexity (LC) and related sequence properties. Composition bias is often associated with LC and disorder, but repeats, while compositionally biased, might also induce ordered structures. We illustrate this dichotomy, plus overlaps between different properties related to LCRs, using examples.
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Affiliation(s)
- Pablo Mier
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University of Mainz, Mainz, Germany
| | - Lisanna Paladin
- Department of Biomedical Science, University of Padova, Padova, Italy
| | - Stella Tamana
- Bioinformatics Research Laboratory, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - Sophia Petrosian
- Biological Computation and Process Laboratory, Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas, Thessalonica, Greece
| | - Borbála Hajdu-Soltész
- MTA-ELTE Lendület Bioinformatics Research Group, Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary
| | - Annika Urbanek
- Centre de Biochimie Structurale, INSERM, CNRS, Université de Montpellier, Montpellier, France
| | - Aleksandra Gruca
- Institute of Informatics, Silesian University of Technology, Gliwice, Poland
| | - Dariusz Plewczynski
- Center of New Technologies, University of Warsaw, Warsaw, Poland.,Faculty of Mathematics and Information Science, Warsaw University of Technology, Warsaw, Poland
| | | | - Pau Bernadó
- Centre de Biochimie Structurale, INSERM, CNRS, Université de Montpellier, Montpellier, France
| | - Zoltán Gáspári
- Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary
| | - Christos A Ouzounis
- Biological Computation and Process Laboratory, Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas, Thessalonica, Greece
| | - Vasilis J Promponas
- Bioinformatics Research Laboratory, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - Andrey V Kajava
- Centre de Recherche en Biologie Cellulaire de Montpellier, CNRS-UMR, Institut de Biologie Computationnelle, Universite de Montpellier, Montpellier, France.,Institute of Bioengineering, University ITMO, St. Petersburg, Russia
| | - John M Hancock
- Earlham Institute, Norwich, UK.,ELIXIR Hub, Welcome Genome Campus, Hinxton, UK
| | - Silvio C E Tosatto
- Department of Biomedical Science, University of Padova, Padova, Italy.,CNR Institute of Neuroscience, Padova, Italy
| | - Zsuzsanna Dosztanyi
- MTA-ELTE Lendület Bioinformatics Research Group, Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary
| | - Miguel A Andrade-Navarro
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University of Mainz, Mainz, Germany
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15
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Assessment of transferable forcefields for protein simulations attests improved description of disordered states and secondary structure propensities, and hints at multi-protein systems as the next challenge for optimization. Comput Struct Biotechnol J 2021; 19:2626-2636. [PMID: 34025949 PMCID: PMC8120800 DOI: 10.1016/j.csbj.2021.04.050] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 04/20/2021] [Accepted: 04/22/2021] [Indexed: 01/02/2023] Open
Abstract
Continuous assessment of transferable forcefields for molecular simulations is essential to identify their weaknesses and direct improvement efforts. The latest efforts focused on better describing disordered proteins while retaining proper description of folded domains, important because forcefields of the previous generations produce overly compact disordered states. Such improvements should additionally alleviate the related problem of over-stabilized protein–protein interactions, which has been largely overlooked. Here we evaluated three state-of-the-art forcefields, current flagships of their respective developers, optimized for ordered and disordered proteins: CHARMM36m with its recommended corrected TIP3P* water, ff19SB with the recommended OPC water, and the 2019 a99SBdisp forcefield by D. E. Shaw Research with its modified TIP4P water; plus ff14SB with TIP3P as an example of the former generation of forcefields. Our evaluation entailed simulations of (i) multiple copies of a protein that is highly soluble yet undergoes weak dimerization, (ii) a disordered peptide with low, well-characterized alpha helical propensity, and (iii) a peptide known to form insoluble β-aggregates. Our results recapitulate ff14SB-TIP3P over-stabilizing aggregates and secondary structures and place a99SBdisp-TIP4PD at the other end i.e. predicting overly weak intermolecular interactions despite reasonably predicting secondary structure propensities. In-between, CHARMM36m-TIP3P* still over-stabilizes aggregates but predicts residue-wise alpha helical propensities in solution slightly better than ff19SB-OPC, while ff19SB-OPC poses the best prediction of weak dimerization of the soluble protein still predicting aggregation of the β-peptides. This independent assessment shows that the claimed forcefield improvements are real, but also that a right balance between noncovalent attraction and repulsion has not yet been reached. We thus propose developers to consider systems like those tested here in their forcefield tuning protocols. Last, the good performance of CHARMM36m-TIP3P* further shows that tuning 3-point water models might still be an alternative to the more costly 4-point models like OPC and TIP4PD.
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16
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Chiki A, Ricci J, Hegde R, Abriata LA, Reif A, Boudeffa D, Lashuel HA. Site-Specific Phosphorylation of Huntingtin Exon 1 Recombinant Proteins Enabled by the Discovery of Novel Kinases. Chembiochem 2021; 22:217-231. [PMID: 32805086 PMCID: PMC8698011 DOI: 10.1002/cbic.202000508] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/17/2020] [Indexed: 12/20/2022]
Abstract
Post-translational modifications (PTMs) within the first 17 amino acids (Nt17) of exon 1 of the Huntingtin protein (Httex1) play important roles in modulating its cellular properties and functions in health and disease. In particular, phosphorylation of threonine and serine residues (T3, S13, and/or S16) has been shown to inhibit Htt aggregation in vitro and inclusion formation in cellular and animal models of Huntington's disease (HD). In this paper, we describe a new and simple methodology for producing milligram quantities of highly pure wild-type or mutant Httex1 proteins that are site-specifically phosphorylated at T3 or at both S13 and S16. This advance was enabled by 1) the discovery and validation of novel kinases that efficiently phosphorylate Httex1 at S13 and S16 (TBK1), at T3 (GCK) or T3 and S13 (TNIK and HGK), and 2) the development of an efficient methodology for producing recombinant native Httex1 proteins by using a SUMO-fusion expression and purification strategy.[26] As a proof of concept, we demonstrate how this method can be applied to produce Httex1 proteins that are both site-specifically phosphorylated and fluorescently or isotopically labeled. Together, these advances should increase access to these valuable tools and expand the range of methods and experimental approaches that can be used to elucidate the mechanisms by which phosphorylation influences Httex1 or HTT structure, aggregation, interactome, and function(s) in health and disease.
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Affiliation(s)
- Anass Chiki
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences Brain Mind InstituteEcole Polytechnique Fédérale de Lausanne (EPFL)Station 191015LausanneSwitzerland
| | - Jonathan Ricci
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences Brain Mind InstituteEcole Polytechnique Fédérale de Lausanne (EPFL)Station 191015LausanneSwitzerland
| | - Ramanath Hegde
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences Brain Mind InstituteEcole Polytechnique Fédérale de Lausanne (EPFL)Station 191015LausanneSwitzerland
| | - Luciano A. Abriata
- Protein Production and Structure Core Facility and Laboratory for Biomolecular ModelingEcole Polytechnique Fédérale de Lausanne (EPFL) and Swiss Institute of Bioinformatics (SIB)1015LausanneSwitzerland
| | - Andreas Reif
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences Brain Mind InstituteEcole Polytechnique Fédérale de Lausanne (EPFL)Station 191015LausanneSwitzerland
| | - Driss Boudeffa
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences Brain Mind InstituteEcole Polytechnique Fédérale de Lausanne (EPFL)Station 191015LausanneSwitzerland
| | - Hilal A. Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences Brain Mind InstituteEcole Polytechnique Fédérale de Lausanne (EPFL)Station 191015LausanneSwitzerland
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17
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Delhommel F, Sattler M. When Less Is More: Combining Site-Specific Isotope Labeling and NMR Unravels Structural Details of Huntingtin Repeats. Structure 2020; 28:730-732. [PMID: 32640252 DOI: 10.1016/j.str.2020.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In this issue of Structure, Urbanek et al. (2020a) combine site-specific isotope labeling and NMR spectroscopy to investigate opposing effects of flanking regions onto the conformation of the poly-Q region in Huntingtin. Poly-Q interactions with preceding residues promote an α-helical conformation while a following proline-rich region favors extended conformations.
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Affiliation(s)
- Florent Delhommel
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany; Bavarian NMR Center and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Garching, Germany
| | - Michael Sattler
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany; Bavarian NMR Center and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Garching, Germany.
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18
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Morató A, Elena-Real CA, Popovic M, Fournet A, Zhang K, Allemand F, Sibille N, Urbanek A, Bernadó P. Robust Cell-Free Expression of Sub-Pathological and Pathological Huntingtin Exon-1 for NMR Studies. General Approaches for the Isotopic Labeling of Low-Complexity Proteins. Biomolecules 2020; 10:E1458. [PMID: 33086646 PMCID: PMC7603387 DOI: 10.3390/biom10101458] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/07/2020] [Accepted: 10/16/2020] [Indexed: 12/23/2022] Open
Abstract
The high-resolution structural study of huntingtin exon-1 (HttEx1) has long been hampered by its intrinsic properties. In addition to being prone to aggregate, HttEx1 contains low-complexity regions (LCRs) and is intrinsically disordered, ruling out several standard structural biology approaches. Here, we use a cell-free (CF) protein expression system to robustly and rapidly synthesize (sub-) pathological HttEx1. The open nature of the CF reaction allows the application of different isotopic labeling schemes, making HttEx1 amenable for nuclear magnetic resonance studies. While uniform and selective labeling facilitate the sequential assignment of HttEx1, combining CF expression with nonsense suppression allows the site-specific incorporation of a single labeled residue, making possible the detailed investigation of the LCRs. To optimize CF suppression yields, we analyze the expression and suppression kinetics, revealing that high concentrations of loaded suppressor tRNA have a negative impact on the final reaction yield. The optimized CF protein expression and suppression system is very versatile and well suited to produce challenging proteins with LCRs in order to enable the characterization of their structure and dynamics.
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Affiliation(s)
| | | | | | | | | | | | | | - Annika Urbanek
- Centre de Biochimie Structurale (CBS), INSERM, CNRS and Université de Montpellier. 29 rue de Navacelles, 34090 Montpellier, France; (A.M.); (C.A.E.-R.); (M.P.); (A.F.); (K.Z.); (F.A.); (N.S.)
| | - Pau Bernadó
- Centre de Biochimie Structurale (CBS), INSERM, CNRS and Université de Montpellier. 29 rue de Navacelles, 34090 Montpellier, France; (A.M.); (C.A.E.-R.); (M.P.); (A.F.); (K.Z.); (F.A.); (N.S.)
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19
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Loureiro RJS, Faísca PFN. The Early Phase of β2-Microglobulin Aggregation: Perspectives From Molecular Simulations. Front Mol Biosci 2020; 7:578433. [PMID: 33134317 PMCID: PMC7550760 DOI: 10.3389/fmolb.2020.578433] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 09/08/2020] [Indexed: 11/24/2022] Open
Abstract
Protein β2-microglobulin is the causing agent of two amyloidosis, dialysis related amyloidosis (DRA), affecting the bones and cartilages of individuals with chronic renal failure undergoing long-term hemodialysis, and a systemic amyloidosis, found in one French family, which impairs visceral organs. The protein’s small size and its biomedical significance attracted the attention of theoretical scientists, and there are now several studies addressing its aggregation mechanism in the context of molecular simulations. Here, we review the early phase of β2-microglobulin aggregation, by focusing on the identification and structural characterization of monomers with the ability to trigger aggregation, and initial small oligomers (dimers, tetramers, hexamers etc.) formed in the so-called nucleation phase. We focus our analysis on results from molecular simulations and integrate our views with those coming from in vitro experiments to provide a broader perspective of this interesting field of research. We also outline directions for future computer simulation studies.
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Affiliation(s)
- Rui J S Loureiro
- Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, University of Lisboa, Lisbon, Portugal
| | - Patrícia F N Faísca
- Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, University of Lisboa, Lisbon, Portugal.,Department of Physics, Faculty of Sciences, University of Lisboa, Lisbon, Portugal
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20
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Moldovean SN, Chiş V. Specific Key-Point Mutations along the Helical Conformation of Huntingtin-Exon 1 Protein Might Have an Antagonistic Effect on the Toxic Helical Content's Formation. ACS Chem Neurosci 2020; 11:2881-2889. [PMID: 32786304 DOI: 10.1021/acschemneuro.0c00493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The polyglutamine tract length represents a key regulator for the Huntington's disease toxicity level and its aggregation rates, often being related to helical structural conformations. In this study, we performed all-atom MD simulations on mutant Huntingtin-Exon1 protein with additional mutation spots, aiming to observe the corresponding structural and dynamical changes at the level of the helix. The simulated structures consist of three sets of Q residue mutations into P residues (4P, 7P, and 9P), with each set including different spots of mutations: random along the mutant sequence (R models), at the edges of the helix (E models), as well as at the edges and in the middle of the helix (EM models). At the helical level, our results predict less compactness profiles for a higher number of P mutations (7P and 9P models) with particular mutation spots at the edges and at the edges-middle of the helix. Moreover, the C-alpha atom distances decreased for 7P and 9P models in comparison to 4P models, and the RMSF values show the highest fluctuation rates for 9P models with point mutations at the edges and in the middle of the helix. The secondary structure analysis suggests greater structural transitions from α-helices to bends, turns, and random coils for 7P and 9P models, particularly for point mutations considered at the edges and in the middle of the helical content. The obtained results support our hypothesis that specific key-point mutations along the helical conformation might have an antagonistic effect on the toxic helical content's formation.
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Affiliation(s)
| | - Vasile Chiş
- Faculty of Physics, Babeş-Bolyai University, Kogălniceanu 1, RO-400084 Cluj-Napoca, Romania
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21
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Chavali S, Singh AK, Santhanam B, Babu MM. Amino acid homorepeats in proteins. Nat Rev Chem 2020; 4:420-434. [PMID: 37127972 DOI: 10.1038/s41570-020-0204-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/04/2020] [Indexed: 12/16/2022]
Abstract
Amino acid homorepeats, or homorepeats, are polypeptide segments found in proteins that contain stretches of identical amino acid residues. Although abnormal homorepeat expansions are linked to pathologies such as neurodegenerative diseases, homorepeats are prevalent in eukaryotic proteomes, suggesting that they are important for normal physiology. In this Review, we discuss recent advances in our understanding of the biological functions of homorepeats, which range from facilitating subcellular protein localization to mediating interactions between proteins across diverse cellular pathways. We explore how the functional diversity of homorepeat-containing proteins could be linked to the ability of homorepeats to adopt different structural conformations, an ability influenced by repeat composition, repeat length and the nature of flanking sequences. We conclude by highlighting how an understanding of homorepeats will help us better characterize and develop therapeutics against the human diseases to which they contribute.
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Affiliation(s)
- Sreenivas Chavali
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, UK.
- Department of Biology, Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati, India.
| | - Anjali K Singh
- Department of Biology, Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati, India
| | - Balaji Santhanam
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, UK
- Department of Structural Biology and Center for Data Driven Discovery, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - M Madan Babu
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, UK.
- Department of Structural Biology and Center for Data Driven Discovery, St. Jude Children's Research Hospital, Memphis, TN, USA.
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22
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Urbanek A, Popovic M, Morató A, Estaña A, Elena-Real CA, Mier P, Fournet A, Allemand F, Delbecq S, Andrade-Navarro MA, Cortés J, Sibille N, Bernadó P. Flanking Regions Determine the Structure of the Poly-Glutamine in Huntingtin through Mechanisms Common among Glutamine-Rich Human Proteins. Structure 2020; 28:733-746.e5. [PMID: 32402249 DOI: 10.1016/j.str.2020.04.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/18/2020] [Accepted: 04/11/2020] [Indexed: 10/24/2022]
Abstract
The causative agent of Huntington's disease, the poly-Q homo-repeat in the N-terminal region of huntingtin (httex1), is flanked by a 17-residue-long fragment (N17) and a proline-rich region (PRR), which promote and inhibit the aggregation propensity of the protein, respectively, by poorly understood mechanisms. Based on experimental data obtained from site-specifically labeled NMR samples, we derived an ensemble model of httex1 that identified both flanking regions as opposing poly-Q secondary structure promoters. While N17 triggers helicity through a promiscuous hydrogen bond network involving the side chains of the first glutamines in the poly-Q tract, the PRR promotes extended conformations in neighboring glutamines. Furthermore, a bioinformatics analysis of the human proteome showed that these structural traits are present in many human glutamine-rich proteins and that they are more prevalent in proteins with longer poly-Q tracts. Taken together, these observations provide the structural bases to understand previous biophysical and functional data on httex1.
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Affiliation(s)
- Annika Urbanek
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 34090 Montpellier, France
| | - Matija Popovic
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 34090 Montpellier, France
| | - Anna Morató
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 34090 Montpellier, France
| | - Alejandro Estaña
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 34090 Montpellier, France; LAAS-CNRS, Université de Toulouse, CNRS, 31400 Toulouse, France
| | - Carlos A Elena-Real
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 34090 Montpellier, France
| | - Pablo Mier
- Institute of Organismic and Molecular Evolution, Faculty of Biology, Johannes Gutenberg University of Mainz, 55128 Mainz, Germany
| | - Aurélie Fournet
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 34090 Montpellier, France
| | - Frédéric Allemand
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 34090 Montpellier, France
| | - Stephane Delbecq
- Laboratoire de Biologie Cellulaire et Moléculaire (LBCM-EA4558 Vaccination Antiparasitaire), UFR Pharmacie, Université de Montpellier, 34090 Montpellier, France
| | - Miguel A Andrade-Navarro
- Institute of Organismic and Molecular Evolution, Faculty of Biology, Johannes Gutenberg University of Mainz, 55128 Mainz, Germany
| | - Juan Cortés
- LAAS-CNRS, Université de Toulouse, CNRS, 31400 Toulouse, France
| | - Nathalie Sibille
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 34090 Montpellier, France
| | - Pau Bernadó
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 34090 Montpellier, France.
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23
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Escobedo A, Chiesa G, Salvatella X. Recombinant Production of Monomeric Isotope-Enriched Aggregation-Prone Peptides: Polyglutamine Tracts and Beyond. Methods Mol Biol 2020; 2141:211-231. [PMID: 32696359 DOI: 10.1007/978-1-0716-0524-0_10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
High solvent exposure of certain sequences located in intrinsically disordered regions (IDRs) may eventually lead to aggregation, as is the case for some low-complexity regions (LCRs) and short linear motifs (SLiMs). In particular, polyglutamine (polyQ) tracts are LCRs of variable length highly enriched in glutamine residues. They are common in transcription factors, and their length can have an impact on transcriptional activity. In nine proteins, polyQ tract expansions beyond specific thresholds cause nine neurodegenerative diseases, and aggregates formed by the protein harboring the polyQ tract can be detected in affected individuals. A structural characterization of polyQ proteins in their monomeric form is key to understand how their expansion can affect their aggregation propensity. In this regard, nuclear magnetic resonance (NMR) spectroscopy can provide high-resolution structural information. Here, we present a protocol to prepare monomeric samples of isotope-enriched short helical polyQ peptides based on the sequence of the androgen receptor (AR) suitable for NMR characterization and suggest different ways to adapt it for the production and monomerization of other relatively short IDR sequences and SLiMs.
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Affiliation(s)
- Albert Escobedo
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Joint BSC-IRB Research Programme in Computational Biology, Barcelona, Spain
| | - Giulio Chiesa
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Joint BSC-IRB Research Programme in Computational Biology, Barcelona, Spain
- Department of Biomedical Engineering and Biological Design Center, Boston University, Boston, MA, USA
| | - Xavier Salvatella
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Barcelona, Spain.
- Joint BSC-IRB Research Programme in Computational Biology, Barcelona, Spain.
- ICREA, Barcelona, Spain.
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24
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Urbanek A, Elena-Real CA, Popovic M, Morató A, Fournet A, Allemand F, Delbecq S, Sibille N, Bernadó P. Site-Specific Isotopic Labeling (SSIL): Access to High-Resolution Structural and Dynamic Information in Low-Complexity Proteins. Chembiochem 2019; 21:769-775. [PMID: 31697025 DOI: 10.1002/cbic.201900583] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/05/2019] [Indexed: 12/17/2022]
Abstract
Remarkable technical progress in the area of structural biology has paved the way to study previously inaccessible targets. For example, large protein complexes can now be easily investigated by cryo-electron microscopy, and modern high-field NMR magnets have challenged the limits of high-resolution characterization of proteins in solution. However, the structural and dynamic characteristics of certain proteins with important functions still cannot be probed by conventional methods. These proteins in question contain low-complexity regions (LCRs), compositionally biased sequences where only a limited number of amino acids is repeated multiple times, which hamper their characterization. This Concept article describes a site-specific isotopic labeling (SSIL) strategy, which combines nonsense suppression and cell-free protein synthesis to overcome these limitations. An overview on how poly-glutamine tracts were made amenable to high-resolution structural studies is used to illustrate the usefulness of SSIL. Furthermore, we discuss the potential of this methodology to give further insights into the roles of LCRs in human pathologies and liquid-liquid phase separation, as well as the challenges that must be addressed in the future for the popularization of SSIL.
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Affiliation(s)
- Annika Urbanek
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 29, rue de Navacelles, 34090, Montpellier, France
| | - Carlos A Elena-Real
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 29, rue de Navacelles, 34090, Montpellier, France
| | - Matija Popovic
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 29, rue de Navacelles, 34090, Montpellier, France
| | - Anna Morató
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 29, rue de Navacelles, 34090, Montpellier, France
| | - Aurélie Fournet
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 29, rue de Navacelles, 34090, Montpellier, France
| | - Frédéric Allemand
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 29, rue de Navacelles, 34090, Montpellier, France
| | - Stephane Delbecq
- Laboratoire de Biologie Cellulaire et Moléculaire, (LBCM-EA4558 Vaccination Antiparasitaire), UFR Pharmacie, Université de Montpellier, 15, Av. Charles Flahault, BP 14491, 34000, Montpellier, France
| | - Nathalie Sibille
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 29, rue de Navacelles, 34090, Montpellier, France
| | - Pau Bernadó
- Centre de Biochimie Structurale (CBS), INSERM, CNRS, Université de Montpellier, 29, rue de Navacelles, 34090, Montpellier, France
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25
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Wanker EE, Ast A, Schindler F, Trepte P, Schnoegl S. The pathobiology of perturbed mutant huntingtin protein-protein interactions in Huntington's disease. J Neurochem 2019; 151:507-519. [PMID: 31418858 DOI: 10.1111/jnc.14853] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 07/08/2019] [Accepted: 08/02/2019] [Indexed: 12/24/2022]
Abstract
Mutations are at the root of many human diseases. Still, we largely do not exactly understand how they trigger pathogenesis. One, more recent, hypothesis has been that they comprehensively perturb protein-protein interaction (PPI) networks and significantly alter key biological processes. Under this premise, many rare genetic disorders with Mendelian inheritance, like Huntington's disease and several spinocerebellar ataxias, are likely to be caused by complex genotype-phenotype relationships involving abnormal PPIs. These altered PPI networks and their effects on cellular pathways are poorly understood at the molecular level. In this review, we focus on PPIs that are perturbed by the expanded pathogenic polyglutamine tract in huntingtin (HTT), the protein which, in its mutated form, leads to the autosomal dominant, neurodegenerative Huntington's disease. One aspect of perturbed mutant HTT interactions is the formation of abnormal protein species such as fibrils or large neuronal inclusions as a result of homotypic and heterotypic aberrant molecular interactions. This review focuses on abnormal PPIs that are associated with the assembly of mutant HTT aggregates in cells and their potential relevance in disease. Furthermore, the mechanisms and pathobiological processes that may contribute to phenotype development, neuronal dysfunction and toxicity in Huntington's disease brains are also discussed. This article is part of the Special Issue "Proteomics".
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Affiliation(s)
- Erich E Wanker
- Neuroproteomics, Max Delbrueck Center for Molecular Medicine, Berlin, Germany
| | - Anne Ast
- Neuroproteomics, Max Delbrueck Center for Molecular Medicine, Berlin, Germany
| | - Franziska Schindler
- Neuroproteomics, Max Delbrueck Center for Molecular Medicine, Berlin, Germany
| | - Philipp Trepte
- Neuroproteomics, Max Delbrueck Center for Molecular Medicine, Berlin, Germany
| | - Sigrid Schnoegl
- Neuroproteomics, Max Delbrueck Center for Molecular Medicine, Berlin, Germany
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26
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Sicorello A, Kelly G, Oregioni A, Nováček J, Sklenář V, Pastore A. The Structural Properties in Solution of the Intrinsically Mixed Folded Protein Ataxin-3. Biophys J 2019; 115:59-71. [PMID: 29972812 DOI: 10.1016/j.bpj.2018.05.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 05/25/2018] [Accepted: 05/29/2018] [Indexed: 10/28/2022] Open
Abstract
It has increasingly become clear over the last two decades that proteins can contain both globular domains and intrinsically unfolded regions that can both contribute to function. Although equally interesting, the disordered regions are difficult to study, because they usually do not crystallize unless bound to partners and are not easily amenable to cryo-electron microscopy studies. NMR spectroscopy remains the best technique to capture the structural features of intrinsically mixed folded proteins and describe their dynamics. These studies rely on the successful assignment of the spectrum, a task not easy per se given the limited spread of the resonances of the disordered residues. Here, we describe the structural properties of ataxin-3, the protein responsible for the neurodegenerative Machado-Joseph disease. Ataxin-3 is a 42-kDa protein containing a globular N-terminal Josephin domain and a C-terminal tail that comprises 13 polyglutamine repeats within a low complexity region. We developed a strategy that allowed us to achieve 87% assignment of the NMR spectrum using a mixed protocol based on high-dimensionality, high-resolution experiments and different labeling schemes. Thanks to the almost complete spectral assignment, we proved that the C-terminal tail is flexible, with extended helical regions, and interacts only marginally with the rest of the protein. We could also, for the first time to our knowledge, observe the structural propensity of the polyglutamine repeats within the context of the full-length protein and show that its structure is stabilized by the preceding region.
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Affiliation(s)
- Alessandro Sicorello
- Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Geoff Kelly
- Medical Research Council Biomolecular NMR Centre, The Francis Crick Institute, London, United Kingdom
| | - Alain Oregioni
- Medical Research Council Biomolecular NMR Centre, The Francis Crick Institute, London, United Kingdom
| | - Jiří Nováček
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Vladimír Sklenář
- Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Annalisa Pastore
- Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom; Department of Molecular Medicine, University of Pavia, Pavia, Italy.
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27
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J S Loureiro R, Vila-Viçosa D, Machuqueiro M, Shakhnovich EI, F N Faísca P. The Early Phase of β2m Aggregation: An Integrative Computational Study Framed on the D76N Mutant and the ΔN6 Variant. Biomolecules 2019; 9:biom9080366. [PMID: 31416179 PMCID: PMC6722664 DOI: 10.3390/biom9080366] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 08/08/2019] [Accepted: 08/13/2019] [Indexed: 12/12/2022] Open
Abstract
Human β2-microglobulin (b2m) protein is classically associated with dialysis-related amyloidosis (DRA). Recently, the single point mutant D76N was identified as the causative agent of a hereditary systemic amyloidosis affecting visceral organs. To get insight into the early stage of the β2m aggregation mechanism, we used molecular simulations to perform an in depth comparative analysis of the dimerization phase of the D76N mutant and the ΔN6 variant, a cleaved form lacking the first six N-terminal residues, which is a major component of ex vivo amyloid plaques from DRA patients. We also provide first glimpses into the tetramerization phase of D76N at physiological pH. Results from extensive protein–protein docking simulations predict an essential role of the C- and N-terminal regions (both variants), as well as of the BC-loop (ΔN6 variant), DE-loop (both variants) and EF-loop (D76N mutant) in dimerization. The terminal regions are more relevant under acidic conditions while the BC-, DE- and EF-loops gain importance at physiological pH. Our results recapitulate experimental evidence according to which Tyr10 (A-strand), Phe30 and His31 (BC-loop), Trp60 and Phe62 (DE-loop) and Arg97 (C-terminus) act as dimerization hot-spots, and further predict the occurrence of novel residues with the ability to nucleate dimerization, namely Lys-75 (EF-loop) and Trp-95 (C-terminus). We propose that D76N tetramerization is mainly driven by the self-association of dimers via the N-terminus and DE-loop, and identify Arg3 (N-terminus), Tyr10, Phe56 (D-strand) and Trp60 as potential tetramerization hot-spots.
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Affiliation(s)
- Rui J S Loureiro
- BioISI-Biosystems & Integrative Sciences Institute, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Diogo Vila-Viçosa
- BioISI-Biosystems & Integrative Sciences Institute and Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Miguel Machuqueiro
- BioISI-Biosystems & Integrative Sciences Institute and Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Eugene I Shakhnovich
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Patrícia F N Faísca
- BioISI-Biosystems & Integrative Sciences Institute and Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
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28
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Matlahov I, van der Wel PC. Conformational studies of pathogenic expanded polyglutamine protein deposits from Huntington's disease. Exp Biol Med (Maywood) 2019; 244:1584-1595. [PMID: 31203656 PMCID: PMC6920524 DOI: 10.1177/1535370219856620] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Huntington’s disease, like other neurodegenerative diseases, continues to lack an
effective cure. Current treatments that address early symptoms ultimately fail
Huntington’s disease patients and their families, with the disease typically
being fatal within 10–15 years from onset. Huntington’s disease is an inherited
disorder with motor and mental impairment, and is associated with the genetic
expansion of a CAG codon repeat encoding a polyglutamine-segment-containing
protein called huntingtin. These Huntington’s disease mutations cause misfolding
and aggregation of fragments of the mutant huntingtin protein, thereby likely
contributing to disease toxicity through a combination of gain-of-toxic-function
for the misfolded aggregates and a loss of function from sequestration of
huntingtin and other proteins. As with other amyloid diseases, the mutant
protein forms non-native fibrillar structures, which in Huntington’s disease are
found within patients’ neurons. The intracellular deposits are associated with
dysregulation of vital processes, and inter-neuronal transport of aggregates may
contribute to disease progression. However, a molecular understanding of these
aggregates and their detrimental effects has been frustrated by insufficient
structural data on the misfolded protein state. In this review, we examine
recent developments in the structural biology of polyglutamine-expanded
huntingtin fragments, and especially the contributions enabled by advances in
solid-state nuclear magnetic resonance spectroscopy. We summarize and discuss
our current structural understanding of the huntingtin deposits and how this
information furthers our understanding of the misfolding mechanism and disease
toxicity mechanisms.
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Affiliation(s)
- Irina Matlahov
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Patrick Ca van der Wel
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA.,Zernike Institute for Advanced Materials, University of Groningen, Groningen 9747 AG, The Netherlands
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29
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Hong JY, Wang DD, Xue W, Yue HW, Yang H, Jiang LL, Wang WN, Hu HY. Structural and dynamic studies reveal that the Ala-rich region of ataxin-7 initiates α-helix formation of the polyQ tract but suppresses its aggregation. Sci Rep 2019; 9:7481. [PMID: 31097749 PMCID: PMC6522498 DOI: 10.1038/s41598-019-43926-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 03/04/2019] [Indexed: 11/26/2022] Open
Abstract
Ataxin-7 (Atx7) is a disease-related protein associated with the pathogenesis of spinocerebellar ataxia 7, while its polyglutamine (polyQ) tract in N-terminus is the causative source of aggregation and proteinopathy. We investigated the structure, dynamics and aggregation properties of the N-terminal 62-residue fragment of Atx7 (Atx7-N) by biochemical and biophysical approaches. The results showed that the normal Atx7-N with a tract of 10 glutamines (10Q) overall adopts a flexible and disordered structure, but it may contain a short or small population of helical structure in solution. PolyQ expansion increases the α-helical propensity of the polyQ tract and consequently enhances its transformation into β-sheet structures during amyloid aggregation. An alanine-rich region (ARR) just ahead of the polyQ tract forms a local and relatively stable α-helix. The ARR α-helix can initiate and stabilize helical formation of the following polyQ tract, but it may suppress aggregation of the polyQ-expanded Atx7-N both in vitro and in cell. Thus, the preceding ARR segment in Atx7-N may influence the dynamic structure and aggregation property of the polyQ tract and even determine the threshold of the pathogenic polyQ lengths. This study may gain structural and dynamic insights into amyloid aggregation of Atx7 and help us further understand the Atx7 proteinopathy based on polyQ expansion.
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Affiliation(s)
- Jun-Ye Hong
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, 200031, P.R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Dong-Dong Wang
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200433, P.R. China
| | - Wei Xue
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, 200031, P.R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Hong-Wei Yue
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, 200031, P.R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Hui Yang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, 200031, P.R. China
| | - Lei-Lei Jiang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, 200031, P.R. China
| | - Wen-Ning Wang
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200433, P.R. China
| | - Hong-Yu Hu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, 200031, P.R. China.
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30
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Escobedo A, Topal B, Kunze MBA, Aranda J, Chiesa G, Mungianu D, Bernardo-Seisdedos G, Eftekharzadeh B, Gairí M, Pierattelli R, Felli IC, Diercks T, Millet O, García J, Orozco M, Crehuet R, Lindorff-Larsen K, Salvatella X. Side chain to main chain hydrogen bonds stabilize a polyglutamine helix in a transcription factor. Nat Commun 2019; 10:2034. [PMID: 31048691 PMCID: PMC6497633 DOI: 10.1038/s41467-019-09923-2] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 04/09/2019] [Indexed: 01/18/2023] Open
Abstract
Polyglutamine (polyQ) tracts are regions of low sequence complexity frequently found in transcription factors. Tract length often correlates with transcriptional activity and expansion beyond specific thresholds in certain human proteins is the cause of polyQ disorders. To study the structural basis of the association between tract length, transcriptional activity and disease, we addressed how the conformation of the polyQ tract of the androgen receptor, associated with spinobulbar muscular atrophy (SBMA), depends on its length. Here we report that this sequence folds into a helical structure stabilized by unconventional hydrogen bonds between glutamine side chains and main chain carbonyl groups, and that its helicity directly correlates with tract length. These unusual hydrogen bonds are bifurcate with the conventional hydrogen bonds stabilizing α-helices. Our findings suggest a plausible rationale for the association between polyQ tract length and androgen receptor transcriptional activity and have implications for establishing the mechanistic basis of SBMA. Polyglutamine (polyQ) tracts are low-complexity regions and their expansion is linked to certain neurodegenerative diseases. Here the authors combine experimental and computational approaches to find that the length of the androgen receptor polyQ tract correlates with its helicity and show that the polyQ helical structure is stabilized by hydrogen bonds between the Gln side chains and main chain carbonyl groups.
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Affiliation(s)
- Albert Escobedo
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028, Barcelona, Spain.,Joint BSC-IRB Research Programme in Computational Biology, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Busra Topal
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028, Barcelona, Spain.,Joint BSC-IRB Research Programme in Computational Biology, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Micha B A Kunze
- Structural Biology and NMR Laboratory, Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Juan Aranda
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028, Barcelona, Spain.,Joint BSC-IRB Research Programme in Computational Biology, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Giulio Chiesa
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028, Barcelona, Spain.,Joint BSC-IRB Research Programme in Computational Biology, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Daniele Mungianu
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028, Barcelona, Spain.,Joint BSC-IRB Research Programme in Computational Biology, Baldiri Reixac 10, 08028, Barcelona, Spain
| | | | - Bahareh Eftekharzadeh
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028, Barcelona, Spain.,Joint BSC-IRB Research Programme in Computational Biology, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Margarida Gairí
- NMR Facility, Scientific and Technological Centers University of Barcelona (CCiTUB), Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Roberta Pierattelli
- CERM and Department of Chemistry "Ugo Schiff", University of Florence, Via Luigi Sacconi 6, Sesto Fiorentino, 50019, Florence, Italy
| | - Isabella C Felli
- CERM and Department of Chemistry "Ugo Schiff", University of Florence, Via Luigi Sacconi 6, Sesto Fiorentino, 50019, Florence, Italy
| | - Tammo Diercks
- CIC bioGUNE, Bizkaia Science and Technology Park bld 801A, 48160, Derio, Bizkaia, Spain
| | - Oscar Millet
- CIC bioGUNE, Bizkaia Science and Technology Park bld 801A, 48160, Derio, Bizkaia, Spain
| | - Jesús García
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028, Barcelona, Spain
| | - Modesto Orozco
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028, Barcelona, Spain.,Joint BSC-IRB Research Programme in Computational Biology, Baldiri Reixac 10, 08028, Barcelona, Spain.,Department of Biochemistry and Biomedicine, University of Barcelona, Avinguda Diagonal 645, 08028, Barcelona, Spain
| | - Ramon Crehuet
- Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, 08034, Barcelona, Spain.
| | - Kresten Lindorff-Larsen
- Structural Biology and NMR Laboratory, Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, 2200, Copenhagen, Denmark.
| | - Xavier Salvatella
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac 10, 08028, Barcelona, Spain. .,Joint BSC-IRB Research Programme in Computational Biology, Baldiri Reixac 10, 08028, Barcelona, Spain. .,ICREA, Passeig Lluís Companys 23, 08010, Barcelona, Spain.
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31
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Probing initial transient oligomerization events facilitating Huntingtin fibril nucleation at atomic resolution by relaxation-based NMR. Proc Natl Acad Sci U S A 2019; 116:3562-3571. [PMID: 30808748 DOI: 10.1073/pnas.1821216116] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The N-terminal region of the huntingtin protein, encoded by exon-1, comprises an amphiphilic domain (httNT), a polyglutamine (Q n ) tract, and a proline-rich sequence. Polyglutamine expansion results in an aggregation-prone protein responsible for Huntington's disease. Here, we study the earliest events involved in oligomerization of a minimalistic construct, httNTQ7, which remains largely monomeric over a sufficiently long period of time to permit detailed quantitative NMR analysis of the kinetics and structure of sparsely populated [Formula: see text] oligomeric states, yet still eventually forms fibrils. Global fitting of concentration-dependent relaxation dispersion, transverse relaxation in the rotating frame, and exchange-induced chemical shift data reveals a bifurcated assembly mechanism in which the NMR observable monomeric species either self-associates to form a productive dimer (τex ∼ 30 μs, K diss ∼ 0.1 M) that goes on to form a tetramer ([Formula: see text] μs; K diss ∼ 22 μM), or exchanges with a "nonproductive" dimer that does not oligomerize further (τex ∼ 400 μs; K diss ∼ 0.3 M). The excited state backbone chemical shifts are indicative of a contiguous helix (residues 3-17) in the productive dimer/tetramer, with only partial helical character in the nonproductive dimer. A structural model of the productive dimer/tetramer was obtained by simulated annealing driven by intermolecular paramagnetic relaxation enhancement data. The tetramer comprises a D 2 symmetric dimer of dimers with largely hydrophobic packing between the helical subunits. The structural model, validated by EPR distance measurements, illuminates the role of the httNT domain in the earliest stages of prenucleation and oligomerization, before fibril formation.
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32
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Levy GR, Shen K, Gavrilov Y, Smith PES, Levy Y, Chan R, Frydman J, Frydman L. Huntingtin's N-Terminus Rearrangements in the Presence of Membranes: A Joint Spectroscopic and Computational Perspective. ACS Chem Neurosci 2019; 10:472-481. [PMID: 30149694 DOI: 10.1021/acschemneuro.8b00353] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Huntington's disease is a neurodegenerative disorder resulting from an expanded polyglutamine (polyQ) repeat of the Huntingtin (Htt) protein. Affected tissues often contain aggregates of the N-terminal Htt exon 1 (Htt-Ex1) fragment. The N-terminal N17 domain proximal to the polyQ tract is key to enhance aggregation and modulate Htt toxicity. Htt-Ex1 is intrinsically disordered, yet it has been postulated that under physiological conditions membranes induce the N17 to adopt an α-helical structure, which then plays a key role in regulating Htt protein aggregation. The present study leverages the recently available assignment of NMR peaks in an N17Q17 construct, in order to provide a look into the changes occurring in vitro upon exposing this fragment to various brain extract fragments as well as to synthetic bilayers. Residue-specific changes were observed by 3D HNCO NMR, whose nature was further clarified with ancillary CD and aggregation studies, as well as with molecular dynamic calculations. From this combination of measurements and computations, a unified picture emerges, whereby transient structures consisting of α-helices spanning a fraction of the N17 residues form during N17Q17-membrane interactions. These interactions are fairly dynamic, but they qualitatively mimic more rigid variants that have been discussed in the literature. The nature of these interactions and their potential influence on the aggregation process of these kinds of constructs under physiological conditions are briefly assessed.
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Affiliation(s)
| | - Koning Shen
- Department of Biology, Stanford University, Stanford, California 94305, United States
| | | | | | | | - Rebecca Chan
- Department of Biology, Stanford University, Stanford, California 94305, United States
| | - Judith Frydman
- Department of Biology, Stanford University, Stanford, California 94305, United States
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33
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Treviño MÁ, Pantoja-Uceda D, Menéndez M, Gomez MV, Mompeán M, Laurents DV. The Singular NMR Fingerprint of a Polyproline II Helical Bundle. J Am Chem Soc 2018; 140:16988-17000. [PMID: 30430829 DOI: 10.1021/jacs.8b05261] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Polyproline II (PPII) helices play vital roles in biochemical recognition events and structures like collagen and form part of the conformational landscapes of intrinsically disordered proteins (IDPs). Nevertheless, this structure is generally hard to detect and quantify. Here, we report the first thorough NMR characterization of a PPII helical bundle protein, the Hypogastrura harveyi "snow flea" antifreeze protein (sfAFP). J-couplings and nuclear Overhauser enhancement spectroscopy confirm a natively folded structure consisting of six PPII helices. NMR spectral analyses reveal quite distinct Hα2 versus Hα3 chemical shifts for 28 Gly residues as well as 13Cα, 15N, and 1HN conformational chemical shifts (Δδ) unique to PPII helical bundles. The 15N Δδ and 1HN Δδ values and small negative 1HN temperature coefficients evince hydrogen-bond formation. 1H-15N relaxation measurements reveal that the backbone structure is generally highly rigid on ps-ns time scales. NMR relaxation parameters and biophysical characterization reveal that sfAFP is chiefly a dimer. For it, a structural model featuring the packing of long, flat hydrophobic faces at the dimer interface is advanced. The conformational stability, measured by amide H/D exchange to be 6.24 ± 0.2 kcal·mol-1, is elevated. These are extraordinary findings considering the great entropic cost of fixing Gly residues and, together with the remarkable upfield chemical shifts of 28 Gly 1Hα, evidence significant stabilizing contributions from CαHα ||| O═C hydrogen bonds. These stabilizing interactions are corroborated by density functional theory calculations and natural bonding orbital analysis. The singular conformational chemical shifts, J-couplings, high hNOE ratios, small negative temperature coefficients, and slowed H/D exchange constitute a unique set of fingerprints to identify PPII helical bundles, which may be formed by hundreds of Gly-rich motifs detected in sequence databases. These results should aid the quantification of PPII helices in IDPs, the development of improved antifreeze proteins, and the incorporation of PPII helices into novel designed proteins.
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Affiliation(s)
- Miguel Ángel Treviño
- "Rocasolano" Institute for Physical Chemistry , Spanish National Research Council , Serrano 119 , 28006 Madrid , Spain
| | - David Pantoja-Uceda
- "Rocasolano" Institute for Physical Chemistry , Spanish National Research Council , Serrano 119 , 28006 Madrid , Spain
| | - Margarita Menéndez
- "Rocasolano" Institute for Physical Chemistry , Spanish National Research Council , Serrano 119 , 28006 Madrid , Spain.,Ciber of Respiratory Diseases (CIBERES) , Melchor Fernández de Almargo 3 , 28029 Madrid , Spain
| | - M Victoria Gomez
- University of Castile-La Mancha, Instituto Regional de Investigación Científica Aplicada (IRICA) , 13071 Ciudad Real , Spain
| | - Miguel Mompeán
- University of Castile-La Mancha, Instituto Regional de Investigación Científica Aplicada (IRICA) , 13071 Ciudad Real , Spain
| | - Douglas V Laurents
- "Rocasolano" Institute for Physical Chemistry , Spanish National Research Council , Serrano 119 , 28006 Madrid , Spain
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34
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Bravo-Arredondo JM, Kegulian NC, Schmidt T, Pandey NK, Situ AJ, Ulmer TS, Langen R. The folding equilibrium of huntingtin exon 1 monomer depends on its polyglutamine tract. J Biol Chem 2018; 293:19613-19623. [PMID: 30315108 DOI: 10.1074/jbc.ra118.004808] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 10/05/2018] [Indexed: 11/06/2022] Open
Abstract
Expansion of the polyglutamine (polyQ) tract in exon 1 of the huntingtin protein (Httex1) leads to Huntington's disease resulting in fatal neurodegeneration. However, it remains poorly understood how polyQ expansions alter protein structure and cause toxicity. Using CD, EPR, and NMR spectroscopy, we found here that monomeric Httex1 consists of two co-existing structural states whose ratio is determined by polyQ tract length. We observed that short Q-lengths favor a largely random-coil state, whereas long Q-lengths increase the proportion of a predominantly α-helical state. We also note that by following a mobility gradient, Httex1 α-helical conformation is restricted to the N-terminal N17 region and to the N-terminal portion of the adjoining polyQ tract. Structuring in both regions was interdependent and likely stabilized by tertiary contacts. Although little helicity was present in N17 alone, each Gln residue in Httex1 enhanced helix stability by 0.03-0.05 kcal/mol, causing a pronounced preference for the α-helical state at pathological Q-lengths. The Q-length-dependent structuring and rigidification could be mimicked in proteins with shorter Q-lengths by a decrease in temperature, indicating that lower temperatures similarly stabilize N17 and polyQ intramolecular contacts. The more rigid α-helical state of Httex1 with an expanded polyQ tract is expected to alter interactions with cellular proteins and modulate the toxic Httex1 misfolding process. We propose that the polyQ-dependent shift in the structural equilibrium may enable future therapeutic strategies that specifically target Httex1 with toxic Q-lengths.
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Affiliation(s)
- Jose M Bravo-Arredondo
- From the Departments of Physiology and Neuroscience and.,the Facultad de Ciencias Básicas, Ingeniería y Tecnología, Universidad Autónoma de Tlaxcala, Calzada Apizaquito S/N, 90300 Apizaco, Tlaxcala, Mexico
| | - Natalie C Kegulian
- Biochemistry and Molecular Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 and
| | - Thomas Schmidt
- Biochemistry and Molecular Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 and
| | | | - Alan J Situ
- From the Departments of Physiology and Neuroscience and
| | - Tobias S Ulmer
- From the Departments of Physiology and Neuroscience and.,Biochemistry and Molecular Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 and
| | - Ralf Langen
- From the Departments of Physiology and Neuroscience and .,Biochemistry and Molecular Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California 90033 and
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35
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Caulkins BG, Cervantes SA, Isas JM, Siemer AB. Dynamics of the Proline-Rich C-Terminus of Huntingtin Exon-1 Fibrils. J Phys Chem B 2018; 122:9507-9515. [PMID: 30252478 DOI: 10.1021/acs.jpcb.8b09213] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Intrinsically disordered protein domains not only are found in soluble proteins but also can be part of large protein complexes or protein aggregates. For example, several amyloid fibrils have intrinsically disordered domains framing a rigid β-sheet-rich core. These disordered domains can often be observed using solution NMR methods in combination with modest magic angle spinning and without perdeuteration. But how can these regions be detected using solution NMR methods when they are part of a fibril that is not tumbling isotropically in solution? Here we addressed this question by investigating the dynamic C-terminus of huntingtin exon-1 (HTTex1) fibrils that are important in Huntington's disease. We assigned the most dynamic regions of the C-terminus of three HTTex1 variants. On the basis of this assignment, we measured site-specific secondary chemical shifts, peak intensities, and R1, R'2, and R1ρ 15N relaxation rates. In addition, we determined the residual 1H-15N dipolar couplings of this region. Our results show that the dipolar couplings are averaged to a very high degree, resulting in an order parameter that is essentially zero. Together, our data show that the C-terminus of HTTex1 is intrinsically disordered and undergoes motions in the high picosecond to low nanosecond range.
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Affiliation(s)
- Bethany G Caulkins
- Department of Physiology & Neuroscience, Zilkha Neurogenetic Institute , Keck School of Medicine of USC , 1501 San Pablo St. , Los Angeles , California 90033 , United States
| | - Silvia A Cervantes
- Department of Physiology & Neuroscience, Zilkha Neurogenetic Institute , Keck School of Medicine of USC , 1501 San Pablo St. , Los Angeles , California 90033 , United States
| | - J Mario Isas
- Department of Physiology & Neuroscience, Zilkha Neurogenetic Institute , Keck School of Medicine of USC , 1501 San Pablo St. , Los Angeles , California 90033 , United States
| | - Ansgar B Siemer
- Department of Physiology & Neuroscience, Zilkha Neurogenetic Institute , Keck School of Medicine of USC , 1501 San Pablo St. , Los Angeles , California 90033 , United States
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36
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Kang H, Luan B, Zhou R. Glassy dynamics in mutant huntingtin proteins. J Chem Phys 2018; 149:072333. [DOI: 10.1063/1.5029369] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Hongsuk Kang
- Institute of Quantitative Biology, Department of Physics, Zhejiang University, Hangzhou 310027, China
- Computational Biology Center, IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598, USA
| | - Binquan Luan
- Computational Biology Center, IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598, USA
| | - Ruhong Zhou
- Institute of Quantitative Biology, Department of Physics, Zhejiang University, Hangzhou 310027, China
- Computational Biology Center, IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598, USA
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37
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Grudziąż K, Zawadzka-Kazimierczuk A, Koźmiński W. High-dimensional NMR methods for intrinsically disordered proteins studies. Methods 2018; 148:81-87. [PMID: 29705209 DOI: 10.1016/j.ymeth.2018.04.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Accepted: 04/24/2018] [Indexed: 01/16/2023] Open
Abstract
Intrinsically disordered proteins (IDPs) are getting more and more interest of the scientific community. Nuclear magnetic resonance (NMR) is often a technique of choice for these studies, as it provides atomic-resolution information on structure, dynamics and interactions of IDPs. Nonetheless, NMR spectra of IDPs are typically extraordinary crowded, comparing to those of structured proteins. To overcome this problem, high-dimensional NMR experiments can be used, which allow for a better peak separation. In the present review different aspects of such experiments are discussed, from data acquisition and processing to analysis, focusing on experiments for resonance assignment.
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Affiliation(s)
- Katarzyna Grudziąż
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Anna Zawadzka-Kazimierczuk
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland
| | - Wiktor Koźmiński
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089 Warsaw, Poland.
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38
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Conformation Polymorphism of Polyglutamine Proteins. Trends Biochem Sci 2018; 43:424-435. [PMID: 29636213 DOI: 10.1016/j.tibs.2018.03.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 03/05/2018] [Accepted: 03/12/2018] [Indexed: 01/29/2023]
Abstract
Expanded polyglutamine (polyQ) stretches within endogenous proteins cause at least nine human diseases. The structural basis of polyQ pathogenesis is the key to understanding fundamental mechanisms of these diseases, but it remains unclear and controversial due to a lack of polyQ protein structures at the single-atom level. Various hypotheses have been proposed to explain the structure-cytotoxicity relationship of pathogenic proteins with polyQ expansion, largely based on indirect evidence. Here we review these hypotheses and their supporting evidence, along with additional insights from recent structural biology and chemical biology studies, with a focus on Huntingtin (HTT), the most extensively studied polyQ disease protein. Lastly, we propose potential novel strategies that may further clarify the conformation-cytotoxicity relationship of polyQ proteins.
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39
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Newcombe EA, Ruff KM, Sethi A, Ormsby AR, Ramdzan YM, Fox A, Purcell AW, Gooley PR, Pappu RV, Hatters DM. Tadpole-like Conformations of Huntingtin Exon 1 Are Characterized by Conformational Heterogeneity that Persists regardless of Polyglutamine Length. J Mol Biol 2018; 430:1442-1458. [PMID: 29627459 DOI: 10.1016/j.jmb.2018.03.031] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 03/21/2018] [Accepted: 03/25/2018] [Indexed: 11/30/2022]
Abstract
Soluble huntingtin exon 1 (Httex1) with expanded polyglutamine (polyQ) engenders neurotoxicity in Huntington's disease. To uncover the physical basis of this toxicity, we performed structural studies of soluble Httex1 for wild-type and mutant polyQ lengths. Nuclear magnetic resonance experiments show evidence for conformational rigidity across the polyQ region. In contrast, hydrogen-deuterium exchange shows absence of backbone amide protection, suggesting negligible persistence of hydrogen bonds. The seemingly conflicting results are explained by all-atom simulations, which show that Httex1 adopts tadpole-like structures with a globular head encompassing the N-terminal amphipathic and polyQ regions and the tail encompassing the C-terminal proline-rich region. The surface area of the globular domain increases monotonically with polyQ length. This stimulates sharp increases in gain-of-function interactions in cells for expanded polyQ, and one of these interactions is with the stress-granule protein Fus. Our results highlight plausible connections between Httex1 structure and routes to neurotoxicity.
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Affiliation(s)
- Estella A Newcombe
- Department of Biochemistry and Molecular Biology, and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC 3010, Australia
| | - Kiersten M Ruff
- Department of Biomedical Engineering and Center for Biological Systems Engineering, Washington University in St. Louis, St Louis, MO 63130, USA
| | - Ashish Sethi
- Department of Biochemistry and Molecular Biology, and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC 3010, Australia
| | - Angelique R Ormsby
- Department of Biochemistry and Molecular Biology, and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC 3010, Australia
| | - Yasmin M Ramdzan
- Department of Biochemistry and Molecular Biology, and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC 3010, Australia
| | - Archa Fox
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, WA 6009, Australia
| | - Anthony W Purcell
- Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia
| | - Paul R Gooley
- Department of Biochemistry and Molecular Biology, and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC 3010, Australia
| | - Rohit V Pappu
- Department of Biomedical Engineering and Center for Biological Systems Engineering, Washington University in St. Louis, St Louis, MO 63130, USA.
| | - Danny M Hatters
- Department of Biochemistry and Molecular Biology, and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, VIC 3010, Australia.
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40
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Urbanek A, Morató A, Allemand F, Delaforge E, Fournet A, Popovic M, Delbecq S, Sibille N, Bernadó P. A General Strategy to Access Structural Information at Atomic Resolution in Polyglutamine Homorepeats. Angew Chem Int Ed Engl 2018; 57:3598-3601. [PMID: 29359503 PMCID: PMC5901001 DOI: 10.1002/anie.201711530] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 12/28/2017] [Indexed: 12/31/2022]
Abstract
Homorepeat (HR) proteins are involved in key biological processes and multiple pathologies, however their high-resolution characterization has been impaired due to their homotypic nature. To overcome this problem, we have developed a strategy to isotopically label individual glutamines within HRs by combining nonsense suppression and cell-free expression. Our method has enabled the NMR investigation of huntingtin exon1 with a 16-residue polyglutamine (poly-Q) tract, and the results indicate the presence of an N-terminal α-helix at near neutral pH that vanishes towards the end of the HR. The generality of the strategy was demonstrated by introducing a labeled glutamine into a pathological version of huntingtin with 46 glutamines. This methodology paves the way to decipher the structural and dynamic perturbations induced by HR extensions in poly-Q-related diseases. Our approach can be extended to other amino acids to investigate biological processes involving proteins containing low-complexity regions (LCRs).
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Affiliation(s)
- Annika Urbanek
- Centre de Biochimie Structurale (CBS), INSERM, CNRSUniversité de Montpellier29 rue de Navacelles34090MontpellierFrance
| | - Anna Morató
- Centre de Biochimie Structurale (CBS), INSERM, CNRSUniversité de Montpellier29 rue de Navacelles34090MontpellierFrance
| | - Frédéric Allemand
- Centre de Biochimie Structurale (CBS), INSERM, CNRSUniversité de Montpellier29 rue de Navacelles34090MontpellierFrance
| | - Elise Delaforge
- Centre de Biochimie Structurale (CBS), INSERM, CNRSUniversité de Montpellier29 rue de Navacelles34090MontpellierFrance
| | - Aurélie Fournet
- Centre de Biochimie Structurale (CBS), INSERM, CNRSUniversité de Montpellier29 rue de Navacelles34090MontpellierFrance
| | - Matija Popovic
- Centre de Biochimie Structurale (CBS), INSERM, CNRSUniversité de Montpellier29 rue de Navacelles34090MontpellierFrance
| | - Stephane Delbecq
- Laboratoire de Biologie Cellulaire et Moléculaire, (LBCM-EA4558 Vaccination Antiparasitaire)UFR PharmacieUniversité de MontpellierMontpellierFrance
| | - Nathalie Sibille
- Centre de Biochimie Structurale (CBS), INSERM, CNRSUniversité de Montpellier29 rue de Navacelles34090MontpellierFrance
| | - Pau Bernadó
- Centre de Biochimie Structurale (CBS), INSERM, CNRSUniversité de Montpellier29 rue de Navacelles34090MontpellierFrance
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41
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Caterino M, Squillaro T, Montesarchio D, Giordano A, Giancola C, Melone MAB. Huntingtin protein: A new option for fixing the Huntington's disease countdown clock. Neuropharmacology 2018. [PMID: 29526547 DOI: 10.1016/j.neuropharm.2018.03.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Huntington's disease is a dreadful, incurable disorder. It springs from the autosomal dominant mutation in the first exon of the HTT gene, which encodes for the huntingtin protein (HTT) and results in progressive neurodegeneration. Thus far, all the attempted approaches to tackle the mutant HTT-induced toxicity causing this disease have failed. The mutant protein comes with the aberrantly expanded poly-glutamine tract. It is primarily to blame for the build-up of β-amyloid-like HTT aggregates, deleterious once broadened beyond the critical ∼35-37 repeats threshold. Recent experimental findings have provided valuable information on the molecular basis underlying this HTT-driven neurodegeneration. These findings indicate that the poly-glutamine siding regions and many post-translation modifications either abet or counter the poly-glutamine tract. This review provides an overall, up-to-date insight into HTT biophysics and structural biology, particularly discussing novel pharmacological options to specifically target the mutated protein and thus inhibit its functions and toxicity.
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Affiliation(s)
- Marco Caterino
- Department of Pharmacy, University of Napoli Federico II, Via D. Montesano 49, 80131, Napoli, Italy
| | - Tiziana Squillaro
- Department of Medical, Surgical, Neurological, Metabolic Sciences, and Aging, 2nd Division of Neurology, Center for Rare Diseases, University of Campania "Luigi Vanvitelli", Napoli, Italy; InterUniversity Center for Research in Neurosciences, University of Campania "Luigi Vanvitelli", Napoli, Italy
| | - Daniela Montesarchio
- InterUniversity Center for Research in Neurosciences, University of Campania "Luigi Vanvitelli", Napoli, Italy; Department of Chemical Sciences, University of Napoli Federico II, Via Cintia 21, 80126, Napoli, Italy
| | - Antonio Giordano
- Sbarro Institute for Cancer Research and Molecular Medicine, Department of Biology, Center for Biotechnology, College of Science and Technology, Temple University, Philadelphia, PA, USA; Department of Medicine, Surgery and Neuroscience University of Siena, Siena, Italy
| | - Concetta Giancola
- Department of Pharmacy, University of Napoli Federico II, Via D. Montesano 49, 80131, Napoli, Italy; InterUniversity Center for Research in Neurosciences, University of Campania "Luigi Vanvitelli", Napoli, Italy.
| | - Mariarosa A B Melone
- Department of Medical, Surgical, Neurological, Metabolic Sciences, and Aging, 2nd Division of Neurology, Center for Rare Diseases, University of Campania "Luigi Vanvitelli", Napoli, Italy; InterUniversity Center for Research in Neurosciences, University of Campania "Luigi Vanvitelli", Napoli, Italy; Sbarro Institute for Cancer Research and Molecular Medicine, Department of Biology, Center for Biotechnology, College of Science and Technology, Temple University, Philadelphia, PA, USA.
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42
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Urbanek A, Morató A, Allemand F, Delaforge E, Fournet A, Popovic M, Delbecq S, Sibille N, Bernadó P. A General Strategy to Access Structural Information at Atomic Resolution in Polyglutamine Homorepeats. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201711530] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Annika Urbanek
- Centre de Biochimie Structurale (CBS), INSERM, CNRS; Université de Montpellier; 29 rue de Navacelles 34090 Montpellier France
| | - Anna Morató
- Centre de Biochimie Structurale (CBS), INSERM, CNRS; Université de Montpellier; 29 rue de Navacelles 34090 Montpellier France
| | - Frédéric Allemand
- Centre de Biochimie Structurale (CBS), INSERM, CNRS; Université de Montpellier; 29 rue de Navacelles 34090 Montpellier France
| | - Elise Delaforge
- Centre de Biochimie Structurale (CBS), INSERM, CNRS; Université de Montpellier; 29 rue de Navacelles 34090 Montpellier France
| | - Aurélie Fournet
- Centre de Biochimie Structurale (CBS), INSERM, CNRS; Université de Montpellier; 29 rue de Navacelles 34090 Montpellier France
| | - Matija Popovic
- Centre de Biochimie Structurale (CBS), INSERM, CNRS; Université de Montpellier; 29 rue de Navacelles 34090 Montpellier France
| | - Stephane Delbecq
- Laboratoire de Biologie Cellulaire et Moléculaire, (LBCM-EA4558 Vaccination Antiparasitaire); UFR Pharmacie; Université de Montpellier; Montpellier France
| | - Nathalie Sibille
- Centre de Biochimie Structurale (CBS), INSERM, CNRS; Université de Montpellier; 29 rue de Navacelles 34090 Montpellier France
| | - Pau Bernadó
- Centre de Biochimie Structurale (CBS), INSERM, CNRS; Université de Montpellier; 29 rue de Navacelles 34090 Montpellier France
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43
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Murrali MG, Schiavina M, Sainati V, Bermel W, Pierattelli R, Felli IC. 13C APSY-NMR for sequential assignment of intrinsically disordered proteins. JOURNAL OF BIOMOLECULAR NMR 2018; 70:167-175. [PMID: 29492731 DOI: 10.1007/s10858-018-0167-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 02/09/2018] [Indexed: 06/08/2023]
Abstract
The increasingly recognized biological relevance of intrinsically disordered proteins requires a continuous expansion of the tools for their characterization via NMR spectroscopy, the only technique so far able to provide atomic-resolution information on these highly mobile macromolecules. Here we present the implementation of projection spectroscopy in 13C-direct detected NMR experiments to achieve the sequence specific assignment of IDPs. The approach was used to obtain the complete backbone assignment at high temperature of α-synuclein, a paradigmatic intrinsically disordered protein.
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Affiliation(s)
- Maria Grazia Murrali
- CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Florence, Italy
| | - Marco Schiavina
- CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Florence, Italy
| | - Valerio Sainati
- CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Florence, Italy
| | - Wolfgang Bermel
- Bruker BioSpin GmbH, Silberstreifen, 76287, Rheinstetten, Germany
| | - Roberta Pierattelli
- CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Florence, Italy.
- Department of Chemistry "Ugo Schiff", University of Florence, 50019, Sesto Fiorentino, Florence, Italy.
| | - Isabella C Felli
- CERM, University of Florence, Via Luigi Sacconi 6, 50019, Sesto Fiorentino, Florence, Italy.
- Department of Chemistry "Ugo Schiff", University of Florence, 50019, Sesto Fiorentino, Florence, Italy.
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44
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Warner JB, Ruff KM, Tan PS, Lemke EA, Pappu RV, Lashuel HA. Monomeric Huntingtin Exon 1 Has Similar Overall Structural Features for Wild-Type and Pathological Polyglutamine Lengths. J Am Chem Soc 2017; 139:14456-14469. [PMID: 28937758 PMCID: PMC5677759 DOI: 10.1021/jacs.7b06659] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Indexed: 12/22/2022]
Abstract
Huntington's disease is caused by expansion of a polyglutamine (polyQ) domain within exon 1 of the huntingtin gene (Httex1). The prevailing hypothesis is that the monomeric Httex1 protein undergoes sharp conformational changes as the polyQ length exceeds a threshold of 36-37 residues. Here, we test this hypothesis by combining novel semi-synthesis strategies with state-of-the-art single-molecule Förster resonance energy transfer measurements on biologically relevant, monomeric Httex1 proteins of five different polyQ lengths. Our results, integrated with atomistic simulations, negate the hypothesis of a sharp, polyQ length-dependent change in the structure of monomeric Httex1. Instead, they support a continuous global compaction with increasing polyQ length that derives from increased prominence of the globular polyQ domain. Importantly, we show that monomeric Httex1 adopts tadpole-like architectures for polyQ lengths below and above the pathological threshold. Our results suggest that higher order homotypic and/or heterotypic interactions within distinct sub-populations of neurons, which are inevitable at finite cellular concentrations, are likely to be the main source of sharp polyQ length dependencies of HD.
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Affiliation(s)
- John B. Warner
- Laboratory
of Molecular and Chemical Biology of Neurodegeneration, Brain Mind
Institute, Station 19, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Kiersten M. Ruff
- Department
of Biomedical Engineering and Center for Biological Systems Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Piau Siong Tan
- Structural
and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
| | - Edward A. Lemke
- Structural
and Computational Biology Unit, Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
| | - Rohit V. Pappu
- Department
of Biomedical Engineering and Center for Biological Systems Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Hilal A. Lashuel
- Laboratory
of Molecular and Chemical Biology of Neurodegeneration, Brain Mind
Institute, Station 19, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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45
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Wang B, Zeng L, Merillat SA, Fischer S, Ochaba J, Thompson LM, Barmada SJ, Scaglione KM, Paulson HL. The ubiquitin conjugating enzyme Ube2W regulates solubility of the Huntington's disease protein, huntingtin. Neurobiol Dis 2017; 109:127-136. [PMID: 28986324 DOI: 10.1016/j.nbd.2017.10.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 08/29/2017] [Accepted: 10/01/2017] [Indexed: 12/20/2022] Open
Abstract
Huntington's disease (HD) is caused by a CAG repeat expansion that encodes a polyglutamine (polyQ) expansion in the HD disease protein, huntingtin (HTT). PolyQ expansion promotes misfolding and aggregation of mutant HTT (mHTT) within neurons. The cellular pathways, including ubiquitin-dependent processes, by which mHTT is regulated remain incompletely understood. Ube2W is the only ubiquitin conjugating enzyme (E2) known to ubiquitinate substrates at their amino (N)-termini, likely favoring substrates with disordered N-termini. By virtue of its N-terminal polyQ domain, HTT has an intrinsically disordered amino terminus. In studies employing immortalized cells, primary neurons and a knock-in (KI) mouse model of HD, we tested the effect of Ube2W deficiency on mHTT levels, aggregation and neurotoxicity. In cultured cells, deficiency of Ube2W activity markedly decreases mHTT aggregate formation and increases the level of soluble monomers, while reducing mHTT-induced cytotoxicity. Consistent with this result, the absence of Ube2W in HdhQ200 KI mice significantly increases levels of soluble monomeric mHTT while reducing insoluble oligomeric species. This study sheds light on the potential function of the non-canonical ubiquitin-conjugating enzyme, Ube2W, in this polyQ neurodegenerative disease.
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Affiliation(s)
- Bo Wang
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA; Neuroscience Program, University of Michigan, Ann Arbor, MI 48109, USA; Department of Dermatology, Ruijin Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Li Zeng
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Neurology, Sichuan Provincial Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, China
| | - Sean A Merillat
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Svetlana Fischer
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Joseph Ochaba
- Department of Neurobiology and Behavior, Institute of Memory Impairment and Neurological Disorders, University of California, Irvine, CA 92697, USA; Department of Psychiatry and Human Behavior, Institute of Memory Impairment and Neurological Disorders, University of California, Irvine, CA 92697, USA
| | - Leslie M Thompson
- Department of Neurobiology and Behavior, Institute of Memory Impairment and Neurological Disorders, University of California, Irvine, CA 92697, USA; Department of Psychiatry and Human Behavior, Institute of Memory Impairment and Neurological Disorders, University of California, Irvine, CA 92697, USA
| | - Sami J Barmada
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Kenneth M Scaglione
- Neuroscience Research Center and Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Henry L Paulson
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109, USA; Neuroscience Program, University of Michigan, Ann Arbor, MI 48109, USA.
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46
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Polyglutamine expansion diseases: More than simple repeats. J Struct Biol 2017; 201:139-154. [PMID: 28928079 DOI: 10.1016/j.jsb.2017.09.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 08/24/2017] [Accepted: 09/15/2017] [Indexed: 12/27/2022]
Abstract
Polyglutamine (polyQ) repeat-containing proteins are widespread in the human proteome but only nine of them are associated with highly incapacitating neurodegenerative disorders. The genetic expansion of the polyQ tract in disease-related proteins triggers a series of events resulting in neurodegeneration. The polyQ tract plays the leading role in the aggregation mechanism, but other elements modulate the aggregation propensity in the context of the full-length proteins, as implied by variations in the length of the polyQ tract required to trigger the onset of a given polyQ disease. Intrinsic features such as the presence of aggregation-prone regions (APRs) outside the polyQ segments and polyQ-flanking sequences, which synergistically participate in the aggregation process, are emerging for several disease-related proteins. The inherent polymorphic structure of polyQ stretches places the polyQ proteins in a central position in protein-protein interaction networks, where interacting partners may additionally shield APRs or reshape the aggregation course. Expansion of the polyQ tract perturbs the cellular homeostasis and contributes to neuronal failure by modulating protein-protein interactions and enhancing toxic oligomerization. Post-translational modifications further regulate self-assembly either by directly altering the intrinsic aggregation propensity of polyQ proteins, by modulating their interaction with different macromolecules or by modifying their withdrawal by the cell quality control machinery. Here we review the recent data on the multifaceted aggregation pathways of disease-related polyQ proteins, focusing on ataxin-3, the protein mutated in Machado-Joseph disease. Further mechanistic understanding of this network of events is crucial for the development of effective therapies for polyQ diseases.
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47
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Ahmed R, VanSchouwen B, Jafari N, Ni X, Ortega J, Melacini G. Molecular Mechanism for the (-)-Epigallocatechin Gallate-Induced Toxic to Nontoxic Remodeling of Aβ Oligomers. J Am Chem Soc 2017; 139:13720-13734. [PMID: 28841302 DOI: 10.1021/jacs.7b05012] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
(-)-Epigallocatechin gallate (EGCG) effectively reduces the cytotoxicity of the Alzheimer's disease β-amyloid peptide (Aβ) by remodeling seeding-competent Aβ oligomers into off-pathway seeding-incompetent Aβ assemblies. However, the mechanism of EGCG-induced remodeling is not fully understood. Here we combine 15N and 1H dark-state exchange saturation transfer (DEST), relaxation, and chemical shift projection NMR analyses with fluorescence, dynamic light scattering, and electron microscopy to elucidate how EGCG remodels Aβ oligomers. We show that the remodeling adheres to a Hill-Scatchard model whereby the Aβ(1-40) self-association occurs cooperatively and generates Aβ(1-40) oligomers with multiple independent binding sites for EGCG with a Kd ∼10-fold lower than that for the Aβ(1-40) monomers. Upon binding to EGCG, the Aβ(1-40) oligomers become less solvent exposed, and the β-regions, which are involved in direct monomer-protofibril contacts in the absence of EGCG, undergo a direct-to-tethered contact shift. This switch toward less engaged monomer-protofibril contacts explains the seeding incompetency observed upon EGCG remodeling and suggests that EGCG interferes with secondary nucleation events known to generate toxic Aβ assemblies. Unexpectedly, the N-terminal residues experience an opposite EGCG-induced shift from tethered to direct contacts, explaining why EGCG remodeling occurs without release of Aβ(1-40) monomers. We also show that upon binding Aβ(1-40) oligomers the relative positions of the EGCG B and D rings change with respect to that of ring A. These distinct structural changes occurring in both Aβ(1-40) oligomers and EGCG during remodeling offer a foundation for understanding the molecular mechanism of EGCG as a neurotoxicity inhibitor. Furthermore, the results reported here illustrate the effectiveness of DEST-based NMR approaches in investigating the mechanism of low-molecular-weight amyloid inhibitors.
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Affiliation(s)
- Rashik Ahmed
- Department of Biochemistry and Biomedical Sciences and ‡Department of Chemistry and Chemical Biology, McMaster University , 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - Bryan VanSchouwen
- Department of Biochemistry and Biomedical Sciences and ‡Department of Chemistry and Chemical Biology, McMaster University , 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - Naeimeh Jafari
- Department of Biochemistry and Biomedical Sciences and ‡Department of Chemistry and Chemical Biology, McMaster University , 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - Xiaodan Ni
- Department of Biochemistry and Biomedical Sciences and ‡Department of Chemistry and Chemical Biology, McMaster University , 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - Joaquin Ortega
- Department of Biochemistry and Biomedical Sciences and ‡Department of Chemistry and Chemical Biology, McMaster University , 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - Giuseppe Melacini
- Department of Biochemistry and Biomedical Sciences and ‡Department of Chemistry and Chemical Biology, McMaster University , 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
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48
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Kang H, Vázquez FX, Zhang L, Das P, Toledo-Sherman L, Luan B, Levitt M, Zhou R. Emerging β-Sheet Rich Conformations in Supercompact Huntingtin Exon-1 Mutant Structures. J Am Chem Soc 2017; 139:8820-8827. [PMID: 28609090 PMCID: PMC5835228 DOI: 10.1021/jacs.7b00838] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
There exists strong correlation between the extended polyglutamines (polyQ) within exon-1 of Huntingtin protein (Htt) and age onset of Huntington's disease (HD); however, the underlying molecular mechanism is still poorly understood. Here we apply extensive molecular dynamics simulations to study the folding of Htt-exon-1 across five different polyQ-lengths. We find an increase in secondary structure motifs at longer Q-lengths, including β-sheet content that seems to contribute to the formation of increasingly compact structures. More strikingly, these longer Q-lengths adopt supercompact structures as evidenced by a surprisingly small power-law scaling exponent (0.22) between the radius-of-gyration and Q-length that is substantially below expected values for compact globule structures (∼0.33) and unstructured proteins (∼0.50). Hydrogen bond analyses further revealed that the supercompact behavior of polyQ is mainly due to the "glue-like" behavior of glutamine's side chains with significantly more side chain-side chain H-bonds than regular proteins in the Protein Data Bank (PDB). The orientation of the glutamine side chains also tend to be "buried" inside, explaining why polyQ domains are insoluble on their own.
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Affiliation(s)
- Hongsuk Kang
- Computational Biology Center, IBM Thomas J. Watson Research Center , Yorktown Heights, New York 10598, United States
| | - Francisco X Vázquez
- Computational Biology Center, IBM Thomas J. Watson Research Center , Yorktown Heights, New York 10598, United States
| | - Leili Zhang
- Computational Biology Center, IBM Thomas J. Watson Research Center , Yorktown Heights, New York 10598, United States
| | - Payel Das
- Computational Biology Center, IBM Thomas J. Watson Research Center , Yorktown Heights, New York 10598, United States
| | | | - Binquan Luan
- Computational Biology Center, IBM Thomas J. Watson Research Center , Yorktown Heights, New York 10598, United States
| | - Michael Levitt
- Department of Structural Biology, Stanford University School of Medicine , Stanford, California 94305, United States
| | - Ruhong Zhou
- Computational Biology Center, IBM Thomas J. Watson Research Center , Yorktown Heights, New York 10598, United States
- Department of Chemistry, Columbia University , New York, New York 10027, United States
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49
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Kosiński K, Stanek J, Górka MJ, Żerko S, Koźmiński W. Reconstruction of non-uniformly sampled five-dimensional NMR spectra by signal separation algorithm. JOURNAL OF BIOMOLECULAR NMR 2017; 68:129-138. [PMID: 28243768 PMCID: PMC5504137 DOI: 10.1007/s10858-017-0095-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 02/08/2017] [Indexed: 05/31/2023]
Abstract
A method for five-dimensional spectral reconstruction of non-uniformly sampled NMR data sets is proposed. It is derived from the previously published signal separation algorithm, with major alterations to avoid unfeasible processing of an entire five-dimensional spectrum. The proposed method allows credible reconstruction of spectra from as little as a few hundred data points and enables sensitive resonance detection in experiments with a high dynamic range of peak intensities. The efficiency of the method is demonstrated on two high-resolution spectra for rapid sequential assignment of intrinsically disordered proteins, namely 5D HN(CA)CONH and 5D (HACA)CON(CO)CONH.
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Affiliation(s)
- Krzysztof Kosiński
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Jan Stanek
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Michał J Górka
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
- Faculty of Physics, Division of Biophysics, Institute of Experimental Physics, University of Warsaw, Pasteura 5, 02-093, Warsaw, Poland
| | - Szymon Żerko
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Wiktor Koźmiński
- Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland.
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50
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Aggregation landscapes of Huntingtin exon 1 protein fragments and the critical repeat length for the onset of Huntington's disease. Proc Natl Acad Sci U S A 2017; 114:4406-4411. [PMID: 28400517 DOI: 10.1073/pnas.1702237114] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Huntington's disease (HD) is a neurodegenerative disease caused by an abnormal expansion in the polyglutamine (polyQ) track of the Huntingtin (HTT) protein. The severity of the disease depends on the polyQ repeat length, arising only in patients with proteins having 36 repeats or more. Previous studies have shown that the aggregation of N-terminal fragments (encoded by HTT exon 1) underlies the disease pathology in mouse models and that the HTT exon 1 gene product can self-assemble into amyloid structures. Here, we provide detailed structural mechanisms for aggregation of several protein fragments encoded by HTT exon 1 by using the associative memory, water-mediated, structure and energy model (AWSEM) to construct their free energy landscapes. We find that the addition of the N-terminal 17-residue sequence ([Formula: see text]) facilitates polyQ aggregation by encouraging the formation of prefibrillar oligomers, whereas adding the C-terminal polyproline sequence ([Formula: see text]) inhibits aggregation. The combination of both terminal additions in HTT exon 1 fragment leads to a complex aggregation mechanism with a basic core that resembles that found for the aggregation of pure polyQ repeats using AWSEM. At the extrapolated physiological concentration, although the grand canonical free energy profiles are uphill for HTT exon 1 fragments having 20 or 30 glutamines, the aggregation landscape for fragments with 40 repeats has become downhill. This computational prediction agrees with the critical length found for the onset of HD and suggests potential therapies based on blocking early binding events involving the terminal additions to the polyQ repeats.
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