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Leach BI, Ferguson JA, Morgan G, Sun X, Kroon G, Oyen D, Dyson HJ, Wright PE. Conformational Dynamics of an Amyloidogenic Intermediate of Transthyretin: Implications for Structural Remodeling and Amyloid Formation. J Mol Biol 2024; 436:168673. [PMID: 38909653 DOI: 10.1016/j.jmb.2024.168673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 06/17/2024] [Accepted: 06/18/2024] [Indexed: 06/25/2024]
Abstract
The aggregation pathway of transthyretin (TTR) proceeds through rate-limiting dissociation of the tetramer (a dimer of dimers) and partial misfolding of the resulting monomer, which assembles into amyloid structures through a downhill polymerization mechanism. The structural features of the aggregation-prone monomeric intermediate are poorly understood. NMR relaxation dispersion offers a unique opportunity to characterize amyloidogenic intermediates when they exchange on favorable timescales with NMR-visible ground states. Here we use NMR to characterize the structure and conformational dynamics of the monomeric F87E mutant of human TTR. Chemical shifts derived from analysis of multinuclear relaxation dispersion data provide insights into the structure of a low-lying excited state that exchanges with the ground state of the F87E monomer at a rate of 3800 s-1. Disruption of the subunit interfaces of the TTR tetramer leads to destabilization of edge strands in both β-sheets of the F87E monomer. Conformational fluctuations are propagated through the entire hydrogen bonding network of the DAGH β-sheet, from the inner β-strand H, which forms the strong dimer-dimer interface in the TTR tetramer, to outer strand D which is unfolded in TTR fibrils. Fluctuations are also propagated from the AB loop in the weak dimer-dimer interface to the EF helix, which undergoes structural remodeling in fibrils. The conformational fluctuations in both regions are enhanced at acidic pH where amyloid formation is most favorable. The relaxation dispersion data provide insights into the conformational dynamics of the amyloidogenic state of monomeric TTR that predispose it for structural remodeling and progression to amyloid fibrils.
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Affiliation(s)
- Benjamin I Leach
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - James A Ferguson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Gareth Morgan
- Departments of Chemistry and Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Xun Sun
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Gerard Kroon
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - David Oyen
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - H Jane Dyson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Peter E Wright
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA; Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
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2
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Nguyen BA, Singh V, Afrin S, Singh P, Pekala M, Ahmed Y, Pedretti R, Canepa J, Lemoff A, Kluve-Beckerman B, Wydorski PM, Chhapra F, Saelices L. Cryo-EM confirms a common fibril fold in the heart of four patients with ATTRwt amyloidosis. Commun Biol 2024; 7:905. [PMID: 39068302 PMCID: PMC11283564 DOI: 10.1038/s42003-024-06588-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2024] [Accepted: 07/15/2024] [Indexed: 07/30/2024] Open
Abstract
ATTR amyloidosis results from the conversion of transthyretin into amyloid fibrils that deposit in tissues causing organ failure and death. This conversion is facilitated by mutations in ATTRv amyloidosis, or aging in ATTRwt amyloidosis. ATTRv amyloidosis exhibits extreme phenotypic variability, whereas ATTRwt amyloidosis presentation is consistent and predictable. Previously, we found unique structural variabilities in cardiac amyloid fibrils from polyneuropathic ATTRv-I84S patients. In contrast, cardiac fibrils from five genotypically different patients with cardiomyopathy or mixed phenotypes are structurally homogeneous. To understand fibril structure's impact on phenotype, it is necessary to study the fibrils from multiple patients sharing genotype and phenotype. Here we show the cryo-electron microscopy structures of fibrils extracted from four cardiomyopathic ATTRwt amyloidosis patients. Our study confirms that they share identical conformations with minimal structural variability, consistent with their homogenous clinical presentation. Our study contributes to the understanding of ATTR amyloidosis biopathology and calls for further studies.
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Affiliation(s)
- Binh An Nguyen
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Virender Singh
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Shumaila Afrin
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Preeti Singh
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Maja Pekala
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Yasmin Ahmed
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Rose Pedretti
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Jacob Canepa
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Andrew Lemoff
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Barbara Kluve-Beckerman
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Pawel M Wydorski
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Farzeen Chhapra
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Lorena Saelices
- Center for Alzheimer's and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA.
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA.
- Peter O'Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA.
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3
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Yoon J, Zhang YM, Her C, Grant RA, Ponomarenko AI, Ackermann BE, Hui T, Lin YS, Debelouchina GT, Shoulders MD. The immune-evasive proline-283 substitution in influenza nucleoprotein increases aggregation propensity without altering the native structure. SCIENCE ADVANCES 2024; 10:eadl6144. [PMID: 38640233 PMCID: PMC11029814 DOI: 10.1126/sciadv.adl6144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 03/15/2024] [Indexed: 04/21/2024]
Abstract
Nucleoprotein (NP) is a key structural protein of influenza ribonucleoprotein complexes and is central to viral RNA packing and trafficking. NP also determines the sensitivity of influenza to myxovirus resistance protein 1 (MxA), an innate immunity factor that restricts influenza replication. A few critical MxA-resistant mutations have been identified in NP, including the highly conserved proline-283 substitution. This essential proline-283 substitution impairs influenza growth, a fitness defect that becomes particularly prominent at febrile temperature (39°C) when host chaperones are depleted. Here, we biophysically characterize proline-283 NP and serine-283 NP to test whether the fitness defect is caused by the proline-283 substitution introducing folding defects. We show that the proline-283 substitution changes the folding pathway of NP, making NP more aggregation prone during folding, but does not alter the native structure of the protein. These findings suggest that influenza has evolved to hijack host chaperones to promote the folding of otherwise biophysically incompetent viral proteins that enable innate immune system escape.
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Affiliation(s)
- Jimin Yoon
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yu Meng Zhang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Cheenou Her
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Robert A. Grant
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Anna I. Ponomarenko
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Bryce E. Ackermann
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Tiffani Hui
- Department of Chemistry, Tufts University, Medford, MA, USA
| | - Yu-Shan Lin
- Department of Chemistry, Tufts University, Medford, MA, USA
| | - Galia T. Debelouchina
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Matthew D. Shoulders
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
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4
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Nguyen BA, Singh V, Afrin S, Singh P, Pekala M, Ahmed Y, Pedretti R, Canepa J, Lemoff A, Kluve-Beckerman B, Wydorski P, Chhapra F, Saelices L. Cryo-EM confirms a common fibril fold in the heart of four patients with ATTRwt amyloidosis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.08.582936. [PMID: 38496656 PMCID: PMC10942412 DOI: 10.1101/2024.03.08.582936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
ATTR amyloidosis results from the conversion of transthyretin into amyloid fibrils that deposit in tissues causing organ failure and death. This conversion is facilitated by mutations in ATTRv amyloidosis, or aging in ATTRwt amyloidosis. ATTRv amyloidosis exhibits extreme phenotypic variability, whereas ATTRwt amyloidosis presentation is consistent and predictable. Previously, we found an unprecedented structural variability in cardiac amyloid fibrils from polyneuropathic ATTRv-I84S patients. In contrast, cardiac fibrils from five genotypically-different patients with cardiomyopathy or mixed phenotypes are structurally homogeneous. To understand fibril structure's impact on phenotype, it is necessary to study the fibrils from multiple patients sharing genotype and phenotype. Here we show the cryo-electron microscopy structures of fibrils extracted from four cardiomyopathic ATTRwt amyloidosis patients. Our study confirms that they share identical conformations with minimal structural variability, consistent with their homogenous clinical presentation. Our study contributes to the understanding of ATTR amyloidosis biopathology and calls for further studies.
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Affiliation(s)
- Binh An Nguyen
- Center for Alzheimer’s and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O’Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Virender Singh
- Center for Alzheimer’s and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O’Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Shumaila Afrin
- Center for Alzheimer’s and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O’Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Preeti Singh
- Center for Alzheimer’s and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O’Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Maja Pekala
- Center for Alzheimer’s and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O’Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Yasmin Ahmed
- Center for Alzheimer’s and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O’Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Rose Pedretti
- Center for Alzheimer’s and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O’Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Jacob Canepa
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Andrew Lemoff
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Barbara Kluve-Beckerman
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Pawel Wydorski
- Center for Alzheimer’s and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O’Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Farzeen Chhapra
- Center for Alzheimer’s and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O’Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
| | - Lorena Saelices
- Center for Alzheimer’s and Neurodegenerative Diseases, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
- Peter O’Donnell Jr Brain Institute, University of Texas Southwestern Medical Center (UTSW), Dallas, TX, USA
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5
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Sun X, Ferguson JA, Yang K, Stanfield RL, Dyson HJ, Wright PE. Mispacking of the F87 sidechain drives aggregation-promoting conformational fluctuations in the subunit interfaces of the transthyretin tetramer. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.26.582172. [PMID: 38464206 PMCID: PMC10925235 DOI: 10.1101/2024.02.26.582172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Aberrant formation and deposition of human transthyretin (TTR) aggregates causes transthyretin amyloidosis. To initialize aggregation, transthyretin tetramers must first dissociate into monomers that partially unfold to promote entry into the aggregation pathway. The native TTR tetramer (T) is stabilized by docking of the F87 sidechain into an interfacial cavity enclosed by several hydrophobic residues including A120. We have previously shown that an alternative tetramer (T*) with mispacked F87 sidechains is more prone to dissociation and aggregation than the native T state. However, the molecular basis for the reduced stability in T* remains unclear. Here we report characterization of the A120L mutant, where steric hindrance is introduced into the F87 binding site. The X-ray structure of A120L shows that the F87 sidechain is displaced from its docking site across the subunit interface. In A120S, a naturally occurring pathogenic mutant that is less aggregation-prone than A120L, the F87 sidechain is correctly docked, as in the native TTR tetramer. Nevertheless, 19F-NMR aggregation assays show an elevated population of a monomeric aggregation intermediate in A120S relative to a control containing the native A120, due to accelerated tetramer dissociation and slowed monomer tetramerization. The mispacking of the F87 sidechain is associated with enhanced exchange dynamics for interfacial residues. At 298 K, the T* populations of various naturally occurring mutants fall between 4-7% (ΔG ~ 1.5-1.9 kcal/mol), consistent with the free energy change expected for undocking and solvent exposure of one of the four F87 sidechains in the tetramer (ΔG ~ 1.6 kcal/mol). Our data provide a molecular-level picture of the likely universal F87 sidechain mispacking in tetrameric TTR that promotes interfacial conformational dynamics and increases aggregation propensity.
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Affiliation(s)
| | | | | | - Robyn L. Stanfield
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, U.S
| | - H. Jane Dyson
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, U.S
| | - Peter E. Wright
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, U.S
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6
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Sun X, Ferguson JA, Leach BI, Stanfield RL, Dyson HJ, Wright PE. Probing the Dissociation Pathway of a Kinetically Labile Transthyretin Mutant. J Am Chem Soc 2024; 146:532-542. [PMID: 38134439 PMCID: PMC10926950 DOI: 10.1021/jacs.3c10083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2023]
Abstract
Aggregation of transthyretin (TTR) is associated with devastating amyloid diseases. Amyloidosis begins with the dissociation of the native homotetramer (a dimer of dimers) to form a monomeric intermediate that assembles into pathogenic aggregates. This process is accelerated in vitro at low pH, but the process by which TTR dissociates and reassembles at neutral pH remains poorly characterized due to the low population of intermediates. Here, we use 19F-nuclear magnetic resonance (NMR) and a highly sensitive trifluoromethyl probe to determine the relative populations of the species formed by the dissociation of a destabilized variant, A25T. The A25T mutation perturbs both the strong dimer and weak dimer-dimer interfaces. A tetramer ⇌ dimer ⇌ monomer (TDM) equilibrium model is proposed to account for concentration- and temperature-dependent population changes. Thermodynamic and kinetic parameters and activation energetics for dissociation of the native A25T tetramer, as well as a destabilized alternative tetramer (T*) with a mispacked F87 side chain, were extracted by van't Hoff and 19F-NMR line shape analysis, saturation transfer, and transition state theory. Chemical shifts for the dimer and T* species are degenerate for 19F and methyl probes close to the strong dimer interface, implicating interfacial perturbation as a common structural feature of these destabilized species. All-atom molecular dynamics simulations further suggest more frequent F87 ring flipping on the nanosecond time scale in the A25T dimer than in the native A25T tetramer. Our integrated approach offers quantitative insights into the energy landscape of the dissociation pathway of TTR at neutral pH.
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Affiliation(s)
- Xun Sun
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - James A Ferguson
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Benjamin I Leach
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Robyn L Stanfield
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - H Jane Dyson
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Peter E Wright
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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7
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Pinheiro F, Varejão N, Sánchez-Morales A, Bezerra F, Navarro S, Velázquez-Campoy A, Busqué F, Almeida MR, Alibés R, Reverter D, Pallarès I, Ventura S. PITB: A high affinity transthyretin aggregation inhibitor with optimal pharmacokinetic properties. Eur J Med Chem 2023; 261:115837. [PMID: 37837673 DOI: 10.1016/j.ejmech.2023.115837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/24/2023] [Accepted: 09/26/2023] [Indexed: 10/16/2023]
Abstract
The aggregation of wild-type transthyretin (TTR) and over 130 genetic TTR variants underlies a group of lethal disorders named TTR amyloidosis (ATTR). TTR chemical chaperones are molecules that hold great promise to modify the course of ATTR progression. In previous studies, we combined rational design and molecular dynamics simulations to generate a series of TTR selective kinetic stabilizers displaying exceptionally high affinities. In an effort to endorse the previously developed molecules with optimal pharmacokinetic properties, we conducted structural design optimization, leading to the development of PITB. PITB binds with high affinity to TTR, effectively inhibiting tetramer dissociation and aggregation of both the wild-type protein and the two most prevalent disease-associated TTR variants. Importantly, PITB selectively binds and stabilizes TTR in plasma, outperforming tolcapone, a drug currently undergoing clinical trials for ATTR. Pharmacokinetic studies conducted on mice confirmed that PITB exhibits encouraging pharmacokinetic properties, as originally intended. Furthermore, PITB demonstrates excellent oral bioavailability and lack of toxicity. These combined attributes position PITB as a lead compound for future clinical trials as a disease-modifying therapy for ATTR.
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Affiliation(s)
- Francisca Pinheiro
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, 08193, Spain
| | - Nathalia Varejão
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, 08193, Spain
| | - Adrià Sánchez-Morales
- Departament de Química, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, 08193, Spain
| | - Filipa Bezerra
- Molecular Neurobiology Group, i3S - Instituto de Investigação e Inovação em Saúde, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal; Departamento de Biologia Molecular, ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313, Porto, Portugal
| | - Susanna Navarro
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, 08193, Spain
| | - Adrián Velázquez-Campoy
- Department of Biochemistry and Molecular & Cellular Biology, and Institute for Biocomputation and Physics of Complex Systems (BIFI), Joint Unit GBsC-CSIC-BIFI, Universidad de Zaragoza, Zaragoza, Spain; Aragon Institute for Health Research, Zaragoza (Spain) and Biomedical Research Network Center in Hepatic and Digestive Diseases (CIBERehd), Madrid, Spain
| | - Félix Busqué
- Departament de Química, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, 08193, Spain
| | - Maria Rosário Almeida
- Molecular Neurobiology Group, i3S - Instituto de Investigação e Inovação em Saúde, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal; Departamento de Biologia Molecular, ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313, Porto, Portugal
| | - Ramon Alibés
- Departament de Química, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, 08193, Spain
| | - David Reverter
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, 08193, Spain
| | - Irantzu Pallarès
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, 08193, Spain.
| | - Salvador Ventura
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, 08193, Spain; ICREA, Passeig Lluis Companys 23, E-08010, Barcelona, Spain.
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8
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Inada Y, Ono Y, Okazaki K, Yamashita T, Kawaguchi T, Kawano S, Kobashigawa Y, Shinya S, Kojima C, Shuto T, Kai H, Morioka H, Sato T. Hydrogen bonds connecting the N-terminal region and the DE loop stabilize the monomeric structure of transthyretin. J Biochem 2023; 174:355-370. [PMID: 37400978 DOI: 10.1093/jb/mvad049] [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: 03/02/2023] [Revised: 06/26/2023] [Accepted: 06/26/2023] [Indexed: 07/05/2023] Open
Abstract
Transthyretin (TTR) is a homo-tetrameric serum protein associated with sporadic and hereditary systemic amyloidosis. TTR amyloid formation proceeds by the dissociation of the TTR tetramer and the subsequent partial unfolding of the TTR monomer into an aggregation-prone conformation. Although TTR kinetic stabilizers suppress tetramer dissociation, a strategy for stabilizing monomers has not yet been developed. Here, we show that an N-terminal C10S mutation increases the thermodynamic stability of the TTR monomer by forming new hydrogen bond networks through the side chain hydroxyl group of Ser10. Nuclear magnetic resonance spectrometry and molecular dynamics simulation revealed that the Ser10 hydroxyl group forms hydrogen bonds with the main chain amide group of either Gly57 or Thr59 on the DE loop. These hydrogen bonds prevent the dissociation of edge strands in the DAGH and CBEF β-sheets during the unfolding of the TTR monomer by stabilizing the interaction between β-strands A and D and the quasi-helical structure in the DE loop. We propose that introducing hydrogen bonds to connect the N-terminal region to the DE loop reduces the amyloidogenic potential of TTR by stabilizing the monomer.
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Affiliation(s)
- Yuki Inada
- Department of Analytical and Biophysical Chemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Yuichiro Ono
- Department of Analytical and Biophysical Chemistry, School of Pharmacy, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Kyo Okazaki
- Department of Analytical and Biophysical Chemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Takuma Yamashita
- Department of Analytical and Biophysical Chemistry, School of Pharmacy, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Tomoyuki Kawaguchi
- Department of Analytical and Biophysical Chemistry, School of Pharmacy, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Shingo Kawano
- Department of Analytical and Biophysical Chemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Yoshihiro Kobashigawa
- Department of Analytical and Biophysical Chemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Shoko Shinya
- Laboratory of Molecular Biophysics, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Chojiro Kojima
- Laboratory of Molecular Biophysics, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
- Division of Materials Science and Chemical Engineering, Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Tsuyoshi Shuto
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Hirofumi Kai
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Hiroshi Morioka
- Department of Analytical and Biophysical Chemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
| | - Takashi Sato
- Department of Analytical and Biophysical Chemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto 862-0973, Japan
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9
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Yoon J, Zhang YM, Her C, Grant RA, Ponomarenko AM, Ackermann BE, Debelouchina GT, Shoulders MD. The Immune-Evasive Proline 283 Substitution in Influenza Nucleoprotein Increases Aggregation Propensity Without Altering the Native Structure. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.08.556894. [PMID: 37745335 PMCID: PMC10515774 DOI: 10.1101/2023.09.08.556894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Nucleoprotein (NP) is a key structural protein of influenza ribonucleoprotein complexes and is central to viral RNA packing and trafficking. In human cells, the interferon induced Myxovirus resistance protein 1 (MxA) binds to NP and restricts influenza replication. This selection pressure has caused NP to evolve a few critical MxA-resistant mutations, particularly the highly conserved Pro283 substitution. Previous work showed that this essential Pro283 substitution impairs influenza growth, and the fitness defect becomes particularly prominent at febrile temperature (39 °C) when host chaperones are depleted. Here, we biophysically characterize Pro283 NP and Ser283 NP to test if the fitness defect is owing to Pro283 substitution introducing folding defects. We show that the Pro283 substitution changes the folding pathway of NP without altering the native structure, making NP more aggregation prone during folding. These findings suggest that influenza has evolved to hijack host chaperones to promote the folding of otherwise biophysically incompetent viral proteins that enable innate immune system escape. Teaser Pro283 substitution in flu nucleoprotein introduces folding defects, and makes influenza uniquely dependent on host chaperones.
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10
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Ma Q, Wang M, Huang Y, Nie Y, Zhang X, Yang DD, Wang Z, Ding S, Qian N, Liu Y, Pan X. Identification of a novel transthyretin mutation D39Y in a cardiac amyloidosis patient and its biochemical characterizations. Front Cardiovasc Med 2023; 10:1091183. [PMID: 36776255 PMCID: PMC9909007 DOI: 10.3389/fcvm.2023.1091183] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 01/09/2023] [Indexed: 01/27/2023] Open
Abstract
Hereditary transthyretin cardiac amyloidosis (hATTR-CA) is a rare autosomal dominantly inherited disease caused by mutations in the transthyretin (TTR) gene. TTR mutations often cause the instability of transthyretin, production of misfolded proteins, and ultimately excessive deposition of insoluble amyloid fibrils in the myocardium, thereby leading to cardiac dysfunction. Herein, we report a novel transthyretin D39Y mutation in a Chinese family. We characterized the kinetic and thermodynamic stabilities of D39Y mutant TTR, revealing that TTR D39Y mutant was less stable than WT TTR and more stable than amyloidogenic mutation TTR L55P. Meanwhile, the only FDA approved drug Tafamidis showed satisfactory inhibitory effect toward ATTR amyloid formation and strong binding affinity in test tube revealed by isothermal titration calorimetry. Finally, we measured the well-folded tetrameric TTR concentration in patient's and his descents' blood serum using a previously reported UPLC-based assay. Notably, the tetramer concentrations gradually increased from symptomatic D39Y gene carrier father, to asymptomatic D39Y gene carrier daughter, and further to wild type daughter, suggesting the decrease in functional tetrameric TTR concentration may serve as an indicator for disease age of onset in D39Y gene carriers. The study described a Chinese family with hATTR-CA due to the TTR variant D39Y with its destabilizing effect in both kinetic and thermodynamic stabilities.
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Affiliation(s)
- Qunchao Ma
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Mengdie Wang
- Chinese Academy of Sciences (CAS) Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China,Department of Chemistry, University of Chinese Academy of Sciences, Beijing, China
| | - Yanan Huang
- Chinese Academy of Sciences (CAS) Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China
| | - Ying Nie
- Instrumentation and Service Center for Physical Sciences, Westlake University, Hangzhou, Zhejiang, China
| | - Xin Zhang
- School of Science, School of Life Sciences, Westlake University, Hangzhou, China,Westlake Laboratory of Life Sciences and Biomedicine, Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou, China
| | - Dan Dan Yang
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Zhuo Wang
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Siyin Ding
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Ningjing Qian
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Yu Liu
- Chinese Academy of Sciences (CAS) Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China,Yu Liu,
| | - Xiaohong Pan
- Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China,*Correspondence: Xiaohong Pan,
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11
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Oral Therapy for the Treatment of Transthyretin-Related Amyloid Cardiomyopathy. Int J Mol Sci 2022; 23:ijms232416145. [PMID: 36555787 PMCID: PMC9788438 DOI: 10.3390/ijms232416145] [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: 12/01/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022] Open
Abstract
The care of systemic amyloidosis has improved dramatically due to improved awareness, accurate diagnostic tools, the development of powerful prognostic and companion biomarkers, and a continuous flow of innovative drugs, which translated into the blooming of phase 2/3 interventional studies for light chain (AL) and transthyretin (ATTR) amyloidosis. The unprecedented availability of effective drugs ignited great interest across various medical specialties, particularly among cardiologists who are now recognizing cardiac amyloidosis at an extraordinary pace. In all amyloidosis referral centers, we are observing a substantial increase in the prevalence of wild-type transthyretin (ATTRwt) cardiomyopathy, which is now becoming the most common form of cardiac amyloidosis. This review focuses on the oral drugs that have been recently introduced for the treatment of ATTR cardiac amyloidosis, for their ease of use in the clinic. They include both old repurposed drugs or fit-for-purpose designed compounds which bind and stabilize the TTR tetramer, thus reducing the formation of new amyloid fibrils, such as tafamidis, diflunisal, and acoramidis, as well as fibril disruptors which have the potential to promote the clearance of amyloid deposits, such as doxycycline. The development of novel therapies is based on the advances in the understanding of the molecular events underlying amyloid cardiomyopathy.
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12
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Pinheiro F, Pallarès I, Peccati F, Sánchez-Morales A, Varejão N, Bezerra F, Ortega-Alarcon D, Gonzalez D, Osorio M, Navarro S, Velázquez-Campoy A, Almeida MR, Reverter D, Busqué F, Alibés R, Sodupe M, Ventura S. Development of a Highly Potent Transthyretin Amyloidogenesis Inhibitor: Design, Synthesis, and Evaluation. J Med Chem 2022; 65:14673-14691. [PMID: 36306808 PMCID: PMC9661476 DOI: 10.1021/acs.jmedchem.2c01195] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Transthyretin amyloidosis
(ATTR) is a group of fatal diseases described
by the misfolding and amyloid deposition of transthyretin (TTR). Discovering
small molecules that bind and stabilize the TTR tetramer, preventing
its dissociation and subsequent aggregation, is a therapeutic strategy
for these pathologies. Departing from the crystal structure of TTR
in complex with tolcapone, a potent binder in clinical trials for
ATTR, we combined rational design and molecular dynamics (MD) simulations
to generate a series of novel halogenated kinetic stabilizers. Among
them, M-23 displays one of the highest affinities for
TTR described so far. The TTR/M-23 crystal structure
confirmed the formation of unprecedented protein–ligand contacts,
as predicted by MD simulations, leading to an enhanced tetramer stability
both in vitro and in whole serum. We demonstrate
that MD-assisted design of TTR ligands constitutes a new avenue for
discovering molecules that, like M-23, hold the potential
to become highly potent drugs to treat ATTR.
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Affiliation(s)
- Francisca Pinheiro
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Irantzu Pallarès
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Francesca Peccati
- Departament de Química, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Adrià Sánchez-Morales
- Departament de Química, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Nathalia Varejão
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Filipa Bezerra
- Molecular Neurobiology Group, i3S−Instituto de Investigação e Inovação em Saúde, IBMC−Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
- Departamento de Biologia Molecular, ICBAS−Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal
| | - David Ortega-Alarcon
- Department of Biochemistry and Molecular & Cellular Biology, and Institute for Biocomputation eand Physics of Complex Systems (BIFI), Joint Unit GBsC-CSIC-BIFI, Universidad de Zaragoza, 50018 Zaragoza, Spain
- Aragon Institute for Health Research, 50009 Zaragoza, Spain
- Biomedical Research Network Center in Hepatic and Digestive Diseases (CIBERehd), 28029 Madrid, Spain
| | - Danilo Gonzalez
- Departament de Química, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Marcelo Osorio
- Departament de Química, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Susanna Navarro
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Adrián Velázquez-Campoy
- Department of Biochemistry and Molecular & Cellular Biology, and Institute for Biocomputation eand Physics of Complex Systems (BIFI), Joint Unit GBsC-CSIC-BIFI, Universidad de Zaragoza, 50018 Zaragoza, Spain
- Aragon Institute for Health Research, 50009 Zaragoza, Spain
- Biomedical Research Network Center in Hepatic and Digestive Diseases (CIBERehd), 28029 Madrid, Spain
| | - Maria Rosário Almeida
- Molecular Neurobiology Group, i3S−Instituto de Investigação e Inovação em Saúde, IBMC−Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
- Departamento de Biologia Molecular, ICBAS−Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal
| | - David Reverter
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Félix Busqué
- Departament de Química, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Ramon Alibés
- Departament de Química, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Mariona Sodupe
- Departament de Química, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
| | - Salvador Ventura
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona 08193, Spain
- ICREA, Passeig Lluis Companys 23, E-08010 Barcelona, Spain
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13
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Reum Han A, Hee Jeon E, Woo Kim K, Ki Lee S, Ohn CY, Jean Park S, Sook Kang N, Koo TS, Bum Hong K, Choi S. Synthesis and biological evaluation of quinolone derivatives as transthyretin amyloidogenesis inhibitors and fluorescence sensors. Bioorg Med Chem 2022; 53:116550. [PMID: 34890995 DOI: 10.1016/j.bmc.2021.116550] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/24/2021] [Accepted: 11/26/2021] [Indexed: 11/17/2022]
Abstract
Under certain conditions, numerous soluble proteins possess an inherent tendency to convert into insoluble amyloid aggregates, which are associated with several sporadic and genetic human diseases. Transthyretin (TTR) is one of the more than 30 human amyloidogenic proteins involved in conditions such as senile systemic amyloidosis, familial amyloid polyneuropathy, and familial amyloid cardiomyopathy. Considerable effort has been focused on identifying the native tetrameric TTR stabilizers to inhibit rate-limiting tetramer dissociation and, consequently, ameliorate TTR amyloidogenesis. Here, we describe the design and synthesis of quinolin-2(1H)-one derivatives that could be structurally complementary to the thyroxine-binding site within tetrameric TTR. Among these quinolin-2(1H)-one derivatives, compound 7a allowed 16.7% of V30M-TTR (3.6 μM) fibril formation at the same concentration and 49.6% at a concentration of 1.8 μM. Compound 7a exhibited much greater potency in complex biological samples like human plasma than that observed with tafamidis, the drug approved for the treatment of TTR amyloid cardiomyopathy for wild-type or hereditary TTR-mediated amyloidosis. Furthermore, the unique spectral properties of compound 7a demonstrated its high potential for TTR quantification, imaging sensors, and fluorescent tools to study the mechanism of TTR amyloidogenesis.
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Affiliation(s)
- Ah Reum Han
- Department of New Drug Discovery and Development, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejon 305-764, Republic of Korea
| | - Eun Hee Jeon
- Department of New Drug Discovery and Development, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejon 305-764, Republic of Korea
| | - Kun Woo Kim
- Department of New Drug Discovery and Development, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejon 305-764, Republic of Korea
| | - Seul Ki Lee
- Department of New Drug Discovery and Development, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejon 305-764, Republic of Korea
| | - Chan-Yeong Ohn
- Department of New Drug Discovery and Development, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejon 305-764, Republic of Korea
| | - Sung Jean Park
- College of Pharmacy and Gachon Institute of Pharmaceutical Sciences, Gachon University, 534-2 Yeonsu 3-dong, Yeonsu-gu, Incheon 406-799, Republic of Korea
| | - Nam Sook Kang
- Department of New Drug Discovery and Development, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejon 305-764, Republic of Korea
| | - Tae-Sung Koo
- Department of New Drug Discovery and Development, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejon 305-764, Republic of Korea
| | - Ki Bum Hong
- New Drug Development Center (NDDC), Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF), 80 Cheombok-ro, Dong-gu, Daegu 701-310, Republic of Korea.
| | - Sungwook Choi
- Department of New Drug Discovery and Development, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejon 305-764, Republic of Korea.
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14
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Gonzalez-Duarte A, Ulloa-Aguirre A. A Brief Journey through Protein Misfolding in Transthyretin Amyloidosis (ATTR Amyloidosis). Int J Mol Sci 2021; 22:ijms222313158. [PMID: 34884963 PMCID: PMC8658192 DOI: 10.3390/ijms222313158] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 11/05/2021] [Accepted: 11/07/2021] [Indexed: 12/23/2022] Open
Abstract
Transthyretin (TTR) amyloidogenesis involves the formation, aggregation, and deposition of amyloid fibrils from tetrameric TTR in different organs and tissues. While the result of amyloidoses is the accumulation of amyloid fibrils resulting in end-organ damage, the nature, and sequence of the molecular causes leading to amyloidosis may differ between the different variants. In addition, fibril accumulation and toxicity vary between different mutations. Structural changes in amyloidogenic TTR have been difficult to identify through X-ray crystallography; but nuclear magnetic resonance spectroscopy has revealed different chemical shifts in the backbone structure of mutated and wild-type TTR, resulting in diverse responses to the cellular conditions or proteolytic stress. Toxic mechanisms of TTR amyloidosis have different effects on different tissues. Therapeutic approaches have evolved from orthotopic liver transplants to novel disease-modifying therapies that stabilize TTR tetramers and gene-silencing agents like small interfering RNA and antisense oligonucleotide therapies. The underlying molecular mechanisms of the different TTR variants could be responsible for the tropisms to specific organs, the age at onset, treatment responses, or disparities in the prognosis.
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Affiliation(s)
- Alejandra Gonzalez-Duarte
- Departamento de Neurología, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Vasco de Quiroga 15, Col. Belisario Dominguez Sección XV, Tlalpan, Mexico City 14080, Mexico
- Correspondence:
| | - Alfredo Ulloa-Aguirre
- Red de Apoyo a la Investigación, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Coordinación de la Investigación Científica, Universidad Nacional Autónoma de México, Mexico City 14080, Mexico;
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15
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The discovery and development of transthyretin amyloidogenesis inhibitors: what are the lessons? Future Med Chem 2021; 13:2083-2105. [PMID: 34633220 DOI: 10.4155/fmc-2021-0248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Transthyretin (TTR) is associated with several human amyloid diseases. Various kinetic stabilizers have been developed to inhibit the dissociation of TTR tetramer and the formation of amyloid fibrils. Most of them are bisaryl derivatives, natural flavonoids, crown ethers and carborans. In this review article, we focus on TTR tetramer stabilizers, genetic therapeutic approaches and fibril remodelers. The binding modes of typical bisaryl derivatives, natural flavonoids, crown ethers and carborans are discussed. Based on knowledge of the binding of thyroxine to TTR tetramer, many stabilizers have been screened to dock into the thyroxine binding sites, leading to TTR tetramer stabilization. Particularly, those stabilizers with unique binding profiles have shown great potential in developing the therapeutic management of TTR amyloidogenesis.
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16
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In Vitro and In Vivo Effects of SerpinA1 on the Modulation of Transthyretin Proteolysis. Int J Mol Sci 2021; 22:ijms22179488. [PMID: 34502397 PMCID: PMC8430710 DOI: 10.3390/ijms22179488] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/26/2021] [Accepted: 08/28/2021] [Indexed: 12/14/2022] Open
Abstract
Transthyretin (TTR) proteolysis has been recognized as a complementary mechanism contributing to transthyretin-related amyloidosis (ATTR amyloidosis). Accordingly, amyloid deposits can be composed mainly of full-length TTR or contain a mixture of both cleaved and full-length TTR, particularly in the heart. The fragmentation pattern at Lys48 suggests the involvement of a serine protease, such as plasmin. The most common TTR variant, TTR V30M, is susceptible to plasmin-mediated proteolysis, and the presence of TTR fragments facilitates TTR amyloidogenesis. Recent studies revealed that the serine protease inhibitor, SerpinA1, was differentially expressed in hepatocyte-like cells (HLCs) from ATTR patients. In this work, we evaluated the effects of SerpinA1 on in vitro and in vivo modulation of TTR V30M proteolysis, aggregation, and deposition. We found that plasmin-mediated TTR proteolysis and aggregation are partially inhibited by SerpinA1. Furthermore, in vivo downregulation of SerpinA1 increased TTR levels in mice plasma and deposition in the cardiac tissue of older animals. The presence of TTR fragments was observed in the heart of young and old mice but not in other tissues following SerpinA1 knockdown. Increased proteolytic activity, particularly plasmin activity, was detected in mice plasmas. Overall, our results indicate that SerpinA1 modulates TTR proteolysis and aggregation in vitro and in vivo.
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17
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Esperante SA, Varejāo N, Pinheiro F, Sant'Anna R, Luque-Ortega JR, Alfonso C, Sora V, Papaleo E, Rivas G, Reverter D, Ventura S. Disease-associated mutations impacting BC-loop flexibility trigger long-range transthyretin tetramer destabilization and aggregation. J Biol Chem 2021; 297:101039. [PMID: 34343569 PMCID: PMC8406001 DOI: 10.1016/j.jbc.2021.101039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 07/30/2021] [Accepted: 07/30/2021] [Indexed: 11/13/2022] Open
Abstract
Hereditary transthyretin amyloidosis (ATTR) is an autosomal dominant disease characterized by the extracellular deposition of the transport protein transthyretin (TTR) as amyloid fibrils. Despite the progress achieved in recent years, understanding why different TTR residue substitutions lead to different clinical manifestations remains elusive. Here, we studied the molecular basis of disease-causing missense mutations affecting residues R34 and K35. R34G and K35T variants cause vitreous amyloidosis, whereas R34T and K35N mutations result in amyloid polyneuropathy and restrictive cardiomyopathy. All variants are more sensitive to pH-induced dissociation and amyloid formation than the wild-type (WT)-TTR counterpart, specifically in the variants deposited in the eyes amyloid formation occurs close to physiological pHs. Chemical denaturation experiments indicate that all the mutants are less stable than WT-TTR, with the vitreous amyloidosis variants, R34G and K35T, being highly destabilized. Sequence-induced stabilization of the dimer–dimer interface with T119M rendered tetramers containing R34G or K35T mutations resistant to pH-induced aggregation. Because R34 and K35 are among the residues more distant to the TTR interface, their impact in this region is therefore theorized to occur at long range. The crystal structures of double mutants, R34G/T119M and K35T/T119M, together with molecular dynamics simulations indicate that their strong destabilizing effect is initiated locally at the BC loop, increasing its flexibility in a mutation-dependent manner. Overall, the present findings help us to understand the sequence-dynamic-structural mechanistic details of TTR amyloid aggregation triggered by R34 and K35 variants and to link the degree of mutation-induced conformational flexibility to protein aggregation propensity.
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Affiliation(s)
- Sebastián A Esperante
- Institut de Biotecnologia i de Biomedicina and Departament de Bioquímica i de Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
| | - Nathalia Varejāo
- Institut de Biotecnologia i de Biomedicina and Departament de Bioquímica i de Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - Francisca Pinheiro
- Institut de Biotecnologia i de Biomedicina and Departament de Bioquímica i de Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - Ricardo Sant'Anna
- Institut de Biotecnologia i de Biomedicina and Departament de Bioquímica i de Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - Juan Román Luque-Ortega
- Molecular Interactions Facility, Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain
| | - Carlos Alfonso
- Systems Biochemistry of Bacterial Division Laboratory, Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain
| | - Valentina Sora
- Computational Biology Laboratory, Danish Cancer Society Research Center, Copenhagen, Denmark; Cancer Systems Biology, Health and Technology Department, Section for Bioinformatics, Technical University of Denmark, Lyngby, Denmark
| | - Elena Papaleo
- Computational Biology Laboratory, Danish Cancer Society Research Center, Copenhagen, Denmark; Cancer Systems Biology, Health and Technology Department, Section for Bioinformatics, Technical University of Denmark, Lyngby, Denmark
| | - Germán Rivas
- Systems Biochemistry of Bacterial Division Laboratory, Centro de Investigaciones Biológicas Margarita Salas, CSIC, Madrid, Spain
| | - David Reverter
- Institut de Biotecnologia i de Biomedicina and Departament de Bioquímica i de Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain
| | - Salvador Ventura
- Institut de Biotecnologia i de Biomedicina and Departament de Bioquímica i de Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
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18
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Ferguson JA, Sun X, Dyson HJ, Wright PE. Thermodynamic Stability and Aggregation Kinetics of EF Helix and EF Loop Variants of Transthyretin. Biochemistry 2021; 60:756-764. [PMID: 33645214 DOI: 10.1021/acs.biochem.1c00073] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Misfolding and aggregation of transthyretin (TTR) are linked to amyloid disease. Amyloidosis occurs when the TTR homotetramer dissociates into aggregation-prone monomers that self-assemble into amyloid. In familial transthyretin amyloidosis, hereditary amino acid substitutions destabilize TTR and promote aggregation. In this work, we used 19F nuclear magnetic resonance (NMR) to determine the effect of mutations in the EF helix (Y78F, K80D, K80E, and A81T) and EF loop (G83R and I84S) on the aggregation kinetics and stability of the TTR tetramer and monomer. The EF region acts as a scaffold that stabilizes interactions in both the strong and weak dimer interfaces of the tetramer and is the site of a cluster of pathogenic mutations. K80D and K80E are non-natural mutants that destabilize the EF helix and yield an equilibrium mixture of tetramer and monomer at neutral pH, providing a unique opportunity to determine the thermodynamic parameters for tetramer assembly under nondenaturing conditions. Of the pathogenic mutants studied, only A81T formed appreciable monomer at neutral pH. Real-time 19F NMR measurements showed that the pathogenic Y78F mutation accelerates aggregation by destabilizing both the tetrameric and monomeric species. The pathogenic mutations A81T, G83R, and I84S destabilize the monomer and increase its aggregation rate by disrupting a Schellman helix C-capping motif. These studies provide new insights into the mechanism by which relatively subtle mutations that affect tetramer or monomer stability promote entry of TTR into the dissociation-aggregation pathway.
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19
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Oligomerization Profile of Human Transthyretin Variants with Distinct Amyloidogenicity. Molecules 2020; 25:molecules25235698. [PMID: 33287192 PMCID: PMC7730986 DOI: 10.3390/molecules25235698] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/05/2020] [Accepted: 11/24/2020] [Indexed: 02/08/2023] Open
Abstract
One of the molecular hallmarks of amyloidoses is ordered protein aggregation involving the initial formation of soluble protein oligomers that eventually grow into insoluble fibrils. The identification and characterization of molecular species critical for amyloid fibril formation and disease development have been the focus of intense analysis in the literature. Here, using photo-induced cross-linking of unmodified proteins (PICUP), we studied the early stages of oligomerization of human transthyretin (TTR), a plasma protein involved in amyloid diseases (ATTR amyloidosis) with multiple clinical manifestations. Upon comparison, the oligomerization processes of wild-type TTR (TTRwt) and several TTR variants (TTRV30M, TTRL55P, and TTRT119M) clearly show distinct oligomerization kinetics for the amyloidogenic variants but a similar oligomerization mechanism. The oligomerization kinetics of the TTR amyloidogenic variants under analysis showed a good correlation with their amyloidogenic potential, with the most amyloidogenic variants aggregating faster (TTRL55P > TTRV30M > TTRwt). Moreover, the early stage oligomerization mechanism for these variants involves stepwise addition of monomeric units to the growing oligomer. A completely different behavior was observed for the nonamyloidogenic TTRT119M variant, which does not form oligomers in the same acidic conditions and even for longer incubation times. Thorough characterization of the initial steps of TTR oligomerization is critical for better understanding the origin of ATTR cytotoxicity and developing novel therapeutic strategies for the treatment of ATTR amyloidosis.
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20
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Dohrn MF, Ihne S, Hegenbart U, Medina J, Züchner SL, Coelho T, Hahn K. Targeting transthyretin - Mechanism-based treatment approaches and future perspectives in hereditary amyloidosis. J Neurochem 2020; 156:802-818. [PMID: 33155274 DOI: 10.1111/jnc.15233] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 10/25/2020] [Accepted: 10/28/2020] [Indexed: 12/19/2022]
Abstract
The liver-derived, circulating transport protein transthyretin (TTR) is the cause of systemic hereditary (ATTRv) and wild-type (ATTRwt) amyloidosis. TTR stabilization and knockdown are approved therapies to mitigate the otherwise lethal disease course. To date, the variety in phenotypic penetrance is not fully understood. This systematic review summarizes the current literature on TTR pathophysiology with its therapeutic implications. Tetramer dissociation is the rate-limiting step of amyloidogenesis. Besides destabilizing TTR mutations, other genetic (RBP4, APCS, AR, ATX2, C1q, C3) and external (extracellular matrix, Schwann cell interaction) factors influence the type of onset and organ tropism. The approved small molecule tafamidis stabilizes the tetramer and significantly decelerates the clinical course. By sequence-specific mRNA knockdown, the approved small interfering RNA (siRNA) patisiran and antisense oligonucleotide (ASO) inotersen both significantly reduce plasma TTR levels and improve neuropathy and quality of life compared to placebo. With enhanced hepatic targeting capabilities, GalNac-conjugated siRNA and ASOs have recently entered phase III clinical trials. Bivalent TTR stabilizers occupy both binding groves in vitro, but have not been tested in trials so far. Tolcapone is another stabilizer with the potential to cross the blood-brain barrier, but its half-life is short and liver failure a potential side effect. Amyloid-directed antibodies and substances like doxycycline aim at reducing the amyloid load, however, none of the yet developed antibodies has successfully passed clinical trials. ATTR-amyloidosis has become a model disease for pathophysiology-based treatment. Further understanding of disease mechanisms will help to overcome the remaining limitations, including application burden, side effects, and blood-brain barrier permeability.
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Affiliation(s)
- Maike F Dohrn
- Department of Neurology, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Dr. John T. Macdonald Foundation, Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Sandra Ihne
- Interdisciplinary Amyloidosis Center of Northern Bavaria, University Hospital of Würzburg, Würzburg, Germany.,Department of Internal Medicine II, Hematology, University Hospital Würzburg, Würzburg, Germany.,Comprehensive Heart Failure Center (CHFC), University and University Hospital Würzburg, Würzburg, Germany
| | - Ute Hegenbart
- Amyloidosis Center Heidelberg, Department of Internal Medicine V, Division of Hematology/Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Jessica Medina
- Dr. John T. Macdonald Foundation, Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Stephan L Züchner
- Dr. John T. Macdonald Foundation, Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami, Miller School of Medicine, Miami, FL, USA
| | - Teresa Coelho
- Andrade's Center for Familial Amyloidosis, University of Porto, Porto, Portugal.,Department of Neurosciences, Hospital de Santo António, Centro Hospitalar Do Porto, University of Porto, Porto, Portugal
| | - Katrin Hahn
- Department of Neurology, Charité University Medicine, Berlin, Germany.,Amyloidosis Center Charité Berlin (ACCB), Charité University Medicine, Berlin, Germany
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21
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Destabilisation of the structure of transthyretin is driven by Ca 2. Int J Biol Macromol 2020; 166:409-423. [PMID: 33129902 DOI: 10.1016/j.ijbiomac.2020.10.199] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 10/08/2020] [Accepted: 10/24/2020] [Indexed: 12/19/2022]
Abstract
Tetrameric transthyretin (TTR) transports thyroid hormones and retinol in plasma and cerebrospinal fluid and performs protective functions under stress conditions. Ageing and mutations result in TTR destabilisation and the formation of the amyloid deposits that dysregulate Ca2+ homeostasis. Our aim was to determine whether Ca2+ affects the structural stability of TTR. We show, using multiple techniques, that Ca2+ does not induce prevalent TTR dissociation and/or oligomerisation. However, in the presence of Ca2+, TTR exhibits altered conformational flexibility and different interactions with the solvent molecules. These structural changes lead to the formation of the sub-populations of non-native TTR conformers and to the destabilisation of the structure of TTR. Moreover, the sub-population of TTR molecules undergoes fragmentation that is augmented by Ca2+. We postulate that Ca2+ constitutes the structural and functional switch between the native and non-native forms of TTR, and therefore tip the balance towards age-dependent pathological calcification.
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22
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Pinheiro F, Varejão N, Esperante S, Santos J, Velázquez-Campoy A, Reverter D, Pallarès I, Ventura S. Tolcapone, a potent aggregation inhibitor for the treatment of familial leptomeningeal amyloidosis. FEBS J 2020; 288:310-324. [PMID: 32324953 DOI: 10.1111/febs.15339] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/31/2020] [Accepted: 04/17/2020] [Indexed: 12/22/2022]
Abstract
Hereditary transthyretin amyloidosis (ATTR) is a disease characterized by the extracellular deposition of transthyretin (TTR) amyloid fibrils. Highly destabilizing TTR mutations cause leptomeningeal amyloidosis, a rare, but fatal, disorder in which TTR aggregates in the brain. The disease remains intractable, since liver transplantation, the reference therapy for systemic ATTR, does not stop mutant TTR production in the brain. In addition, despite current pharmacological strategies have shown to be effective against in vivo TTR aggregation by stabilizing the tetramer native structure and precluding its dissociation, they display low brain permeability. Recently, we have repurposed tolcapone as a molecule to treat systemic ATTR. Crystal structures and biophysical analysis converge to demonstrate that tolcapone binds with high affinity and specificity to three unstable leptomeningeal TTR variants, stabilizing them and, consequently, inhibiting their aggregation. Because tolcapone is an FDA-approved drug that crosses the blood-brain barrier, our results suggest that it can translate into a first disease-modifying therapy for leptomeningeal amyloidosis. DATABASES: PDB codes for A25T-TTR, V30G-TTR, and Y114C-TTR bound to tolcapone are 6TXV, 6TXW, and 6XTK, respectively.
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Affiliation(s)
- Francisca Pinheiro
- Departament de Bioquímica i Biologia Molecular, Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Spain
| | - Nathalia Varejão
- Departament de Bioquímica i Biologia Molecular, Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Spain
| | | | - Jaime Santos
- Departament de Bioquímica i Biologia Molecular, Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Spain
| | - Adrián Velázquez-Campoy
- Department of Biochemistry and Molecular & Cellular Biology, Institute for Biocomputation and Physics of Complex Systems (BIFI), Joint Units IQFR-CSIC-BIFI and GBsC-CSIC-BIFI, Universidad de Zaragoza, Spain.,Aragon Institute for Health Research, Zaragoza, Spain.,Biomedical Research Network Center in Hepatic and Digestive Diseases (CIBERehd), Madrid, Spain.,ARAID Foundation, Gobierno de Aragón, Zaragoza, Spain
| | - David Reverter
- Departament de Bioquímica i Biologia Molecular, Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Spain
| | - Irantzu Pallarès
- Departament de Bioquímica i Biologia Molecular, Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Spain
| | - Salvador Ventura
- Departament de Bioquímica i Biologia Molecular, Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Spain
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23
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Boyer DR, Li B, Sun C, Fan W, Zhou K, Hughes MP, Sawaya MR, Jiang L, Eisenberg DS. The α-synuclein hereditary mutation E46K unlocks a more stable, pathogenic fibril structure. Proc Natl Acad Sci U S A 2020; 117:3592-3602. [PMID: 32015135 PMCID: PMC7035510 DOI: 10.1073/pnas.1917914117] [Citation(s) in RCA: 113] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Aggregation of α-synuclein is a defining molecular feature of Parkinson's disease, Lewy body dementia, and multiple systems atrophy. Hereditary mutations in α-synuclein are linked to both Parkinson's disease and Lewy body dementia; in particular, patients bearing the E46K disease mutation manifest a clinical picture of parkinsonism and Lewy body dementia, and E46K creates more pathogenic fibrils in vitro. Understanding the effect of these hereditary mutations on α-synuclein fibril structure is fundamental to α-synuclein biology. We therefore determined the cryo-electron microscopy (cryo-EM) structure of α-synuclein fibrils containing the hereditary E46K mutation. The 2.5-Å structure reveals a symmetric double protofilament in which the molecules adopt a vastly rearranged, lower energy fold compared to wild-type fibrils. We propose that the E46K misfolding pathway avoids electrostatic repulsion between K46 and K80, a residue pair which form the E46-K80 salt bridge in the wild-type fibril structure. We hypothesize that, under our conditions, the wild-type fold does not reach this deeper energy well of the E46K fold because the E46-K80 salt bridge diverts α-synuclein into a kinetic trap-a shallower, more accessible energy minimum. The E46K mutation apparently unlocks a more stable and pathogenic fibril structure.
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Affiliation(s)
- David R Boyer
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- Department of Biological Chemistry, University of California, Los Angeles, CA 90095
- Department of Energy Institute, University of California, Los Angeles, CA 90095
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
- Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095
| | - Binsen Li
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Chuanqi Sun
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Weijia Fan
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Kang Zhou
- California NanoSystems Institute, University of California, Los Angeles, CA 90095
| | - Michael P Hughes
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- Department of Biological Chemistry, University of California, Los Angeles, CA 90095
- Department of Energy Institute, University of California, Los Angeles, CA 90095
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
- Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095
| | - Michael R Sawaya
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095
- Department of Biological Chemistry, University of California, Los Angeles, CA 90095
- Department of Energy Institute, University of California, Los Angeles, CA 90095
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
- Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095
| | - Lin Jiang
- Molecular Biology Institute, University of California, Los Angeles, CA 90095;
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - David S Eisenberg
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095;
- Department of Biological Chemistry, University of California, Los Angeles, CA 90095
- Department of Energy Institute, University of California, Los Angeles, CA 90095
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
- Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095
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24
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Loconte V, Menozzi I, Ferrari A, Folli C, Imbimbo BP, Zanotti G, Berni R. Structure-activity relationships of flurbiprofen analogues as stabilizers of the amyloidogenic protein transthyretin. J Struct Biol 2019; 208:165-173. [DOI: 10.1016/j.jsb.2019.08.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 07/25/2019] [Accepted: 08/26/2019] [Indexed: 10/26/2022]
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25
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Pan W, Wang Y, Wang N. A new metal affinity NCTR 25 tag as a better alternative to the His-tag for the expression of recombinant fused proteins. Protein Expr Purif 2019; 164:105477. [PMID: 31419547 DOI: 10.1016/j.pep.2019.105477] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 07/20/2019] [Accepted: 08/11/2019] [Indexed: 12/18/2022]
Abstract
His-tagging is commonly used in fusion protein production, but the His-tag is usually prohibited in medicinal proteins and must be removed. A fragment (NCTR25-tag) truncated from the N-terminus of human copper transporter 1 was tested for feasibility as a replacement for the His-tag in fusion proteins. The NCTR25-tag and His-tag were separately fused to the transthyretin (TTR) protein, and the expression, affinity purification, refolding and stability of the two kinds of fusions were compared. NCTR25 fusion produced a 63% higher yield of the recombinant protein, which was purified by metal affinity chromatography with an efficiency similar to that of His-tagged protein. NCTR25-tag fusion had much less impact on the foldability, kinetic and thermodynamic stability of tetrameric TTR than His-tag fusion. When the tags were individually fused to enhanced green fluorescent protein (EGFP), NCTR25 fusion yielded 29-128% more product than His-EGFP. NCTR25-EGFP could be purified by metal affinity chromatography and showed better foldability than His-EGFP. Furthermore, tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) fusion with the third disulfide loop of TGF-α (TGF3L-TRAIL) fused with the NCTR25-tag retained the stability and superactivity of His-TGF3L-TRAIL. Therefore, the native tag NCTR25-tag is a feasible alternative to the His-tag in medicinal recombinant proteins.
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Affiliation(s)
- Weitong Pan
- Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China
| | - Yan Wang
- Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
| | - Nan Wang
- Beijing Key Laboratory of New Drug Mechanisms and Pharmacological Evaluation Study, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People's Republic of China.
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26
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Lampkin BJ, Monteiro C, Powers ET, Bouc PM, Kelly JW, VanVeller B. A designed protein binding-pocket to control excited-state intramolecular proton transfer fluorescence. Org Biomol Chem 2019; 17:1076-1080. [PMID: 30534794 PMCID: PMC6549506 DOI: 10.1039/c8ob02673d] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Excited-state intramolecular proton transfer involves a photochemical isomerization and creates the opportunity for the emission of two distinct wavelengths of light from a single fluorophore. The selectivity between these two wavelengths of emission is dependent on the environment around the fluorophore and suggests the possibility for ratiometric monitoring of protein microenvironments. Unfortunately, nonspecific binding of ESIPT fluorophores does not often lead to dramatic changes in the ratio between the two wavelengths of emission. A protein binding pocket was designed to selectively discriminate between the two channels of emission available to an ESIPT fluorophore. This work is significant because it demonstrates that specific interactions between the protein and the fluorophore are essential to realize strong ratiometric differences between the two possible wavelengths of emission. The design strategies proposed here lead to an ESIPT fluorophore that can discern subtle differences in the interface between two proteins.
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Affiliation(s)
- Bryan J Lampkin
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
| | - Cecilia Monteiro
- Department of Chemistry, Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Evan T Powers
- Department of Chemistry, Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Paige M Bouc
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
| | - Jeffery W Kelly
- Department of Chemistry, Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Brett VanVeller
- Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.
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27
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Assessment of the effects of transthyretin peptide inhibitors in Drosophila models of neuropathic ATTR. Neurobiol Dis 2018; 120:118-125. [PMID: 30213731 DOI: 10.1016/j.nbd.2018.09.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/20/2018] [Accepted: 09/06/2018] [Indexed: 11/21/2022] Open
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28
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Leach BI, Zhang X, Kelly JW, Dyson HJ, Wright PE. NMR Measurements Reveal the Structural Basis of Transthyretin Destabilization by Pathogenic Mutations. Biochemistry 2018; 57:4421-4430. [PMID: 29972637 PMCID: PMC6067956 DOI: 10.1021/acs.biochem.8b00642] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Inherited mutations of transthyretin (TTR) destabilize its structure, leading to aggregation and familial amyloid disease. Although numerous crystal structures of wild-type (WT) and mutant TTRs have been determined, they have failed to yield a comprehensive structural explanation for destabilization by pathogenic mutations. To identify structural and dynamic variations that are not readily observed in the crystal structures, we used NMR to study WT TTR and three kinetically and/or thermodynamically destabilized pathogenic variants (V30M, L55P, and V122I). Sequence-corrected chemical shifts reveal important structural differences between WT and mutant TTR. The L55P mutation linked to aggressive early onset cardiomyopathy and polyneuropathy induces substantial structural perturbations in both the DAGH and CBEF β-sheets, whereas the V30M polyneuropathy-linked substitution perturbs primarily the CBEF sheet. In both variants, the structural perturbations propagate across the entire width of the β-sheets from the site of mutation. Structural changes caused by the V122I cardiomyopathy-associated mutation are restricted to the immediate vicinity of the mutation site, directly perturbing the subunit interfaces. NMR relaxation dispersion measurements show that WT TTR and the three pathogenic variants undergo millisecond time scale conformational fluctuations to populate a common excited state with an altered structure in the subunit interfaces. The excited state is most highly populated in L55P. The combined application of chemical shift analysis and relaxation dispersion to these pathogenic variants reveals differences in ground state structure and in the population of a transient excited state that potentially facilitates tetramer dissociation, providing new insights into the molecular mechanism by which mutations promote TTR amyloidosis.
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Affiliation(s)
- Benjamin I. Leach
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California, 92037
| | - Xin Zhang
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania16802
| | - Jeffery W. Kelly
- Department of Chemistry and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California, 92037
| | - H. Jane Dyson
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California, 92037
| | - Peter E. Wright
- Department of Integrative Structural and Computational Biology and Skaggs Institute of Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California, 92037
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29
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Saelices L, Chung K, Lee JH, Cohn W, Whitelegge JP, Benson MD, Eisenberg DS. Amyloid seeding of transthyretin by ex vivo cardiac fibrils and its inhibition. Proc Natl Acad Sci U S A 2018; 115:E6741-E6750. [PMID: 29954863 PMCID: PMC6055172 DOI: 10.1073/pnas.1805131115] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Each of the 30 human amyloid diseases is associated with the aggregation of a particular precursor protein into amyloid fibrils. In transthyretin amyloidosis (ATTR), mutant or wild-type forms of the serum carrier protein transthyretin (TTR), synthesized and secreted by the liver, convert to amyloid fibrils deposited in the heart and other organs. The current standard of care for hereditary ATTR is liver transplantation, which replaces the mutant TTR gene with the wild-type gene. However, the procedure is often followed by cardiac deposition of wild-type TTR secreted by the new liver. Here we find that amyloid fibrils extracted from autopsied and explanted hearts of ATTR patients robustly seed wild-type TTR into amyloid fibrils in vitro. Cardiac-derived ATTR seeds can accelerate fibril formation of wild-type and monomeric TTR at acidic pH and under physiological conditions, respectively. We show that this seeding is inhibited by peptides designed to complement structures of TTR fibrils. These inhibitors cap fibril growth, suggesting an approach for halting progression of ATTR.
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Affiliation(s)
- Lorena Saelices
- Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095
- UCLA-DOE, University of California, Los Angeles, CA 90095
- Department of Biological Chemistry, University of California, Los Angeles, CA 90095
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
| | - Kevin Chung
- Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095
- UCLA-DOE, University of California, Los Angeles, CA 90095
- Department of Biological Chemistry, University of California, Los Angeles, CA 90095
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
| | - Ji H Lee
- Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095
- UCLA-DOE, University of California, Los Angeles, CA 90095
- Department of Biological Chemistry, University of California, Los Angeles, CA 90095
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
| | - Whitaker Cohn
- Neuropsychiatric Institute (NPI)-Semel Institute, University of California, Los Angeles, CA 90024
| | - Julian P Whitelegge
- Neuropsychiatric Institute (NPI)-Semel Institute, University of California, Los Angeles, CA 90024
| | - Merrill D Benson
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202
| | - David S Eisenberg
- Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095;
- UCLA-DOE, University of California, Los Angeles, CA 90095
- Department of Biological Chemistry, University of California, Los Angeles, CA 90095
- Molecular Biology Institute, University of California, Los Angeles, CA 90095
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30
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Garai K, Posey AE, Li X, Buxbaum JN, Pappu RV. Inhibition of amyloid beta fibril formation by monomeric human transthyretin. Protein Sci 2018; 27:1252-1261. [PMID: 29498118 PMCID: PMC6032350 DOI: 10.1002/pro.3396] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 02/26/2018] [Accepted: 02/27/2018] [Indexed: 11/11/2022]
Abstract
Transthyretin (TTR) is a homotetrameric protein that is found in the plasma and cerebrospinal fluid. Dissociation of TTR tetramers sets off a downhill cascade of amyloid formation through polymerization of monomeric TTR. Interestingly, TTR has an additional, biologically relevant activity, which pertains to its ability to slow the progression of amyloid beta (Aβ) associated pathology in transgenic mice. In vitro, both TTR and a kinetically stable variant of monomeric TTR (M-TTR) inhibit the fibril formation of Aβ1-40/42 molecules. Published evidence suggests that tetrameric TTR binds preferentially to Aβ monomers, thus destabilizing fibril formation by depleting the pool of Aβ monomers from aggregating mixtures. Here, we investigate the effects of M-TTR on the in vitro aggregation of Aβ1-42 . Our data confirm previous observations that fibril formation of Aβ is suppressed in the presence of sub-stoichiometric amounts of M-TTR. Despite this, we find that sub-stoichiometric levels of M-TTR are not bona fide inhibitors of aggregation. Instead, they co-aggregate with Aβ to promote the formation of large, micron-scale insoluble, non-fibrillar amorphous deposits. Based on fluorescence correlation spectroscopy measurements, we find that M-TTR does not interact with monomeric Aβ. Two-color coincidence analysis of the fluorescence bursts of Aβ and M-TTR labeled with different fluorophores shows that M-TTR co-assembles with soluble Aβ aggregates and this appears to drive the co-aggregation into amorphous precipitates. Our results suggest that mimicking the co-aggregation activity with protein-based therapeutics might be a worthwhile strategy for rerouting amyloid beta peptides into inert, insoluble, and amorphous deposits.
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Affiliation(s)
- Kanchan Garai
- Department of Biomedical Engineering and Center for Biological Systems EngineeringWashington University in St. Louis, One Brookings Drive, Campus Box 1097St. LouisMissouri63130
- TIFR Centre for Interdisciplinary Sciences, 36/P Gopanpally Village, SerilingampallyHyderabad500019India
| | - Ammon E. Posey
- Department of Biomedical Engineering and Center for Biological Systems EngineeringWashington University in St. Louis, One Brookings Drive, Campus Box 1097St. LouisMissouri63130
| | - Xinyi Li
- Department of Molecular and Experimental MedicineThe Scripps Research Institute, 10550 North Torey Pines RoadLa JollaCalifornia92037
| | - Joel N. Buxbaum
- Department of Molecular and Experimental MedicineThe Scripps Research Institute, 10550 North Torey Pines RoadLa JollaCalifornia92037
| | - Rohit V. Pappu
- Department of Biomedical Engineering and Center for Biological Systems EngineeringWashington University in St. Louis, One Brookings Drive, Campus Box 1097St. LouisMissouri63130
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Unusual duplication mutation in a surface loop of human transthyretin leads to an aggressive drug-resistant amyloid disease. Proc Natl Acad Sci U S A 2018; 115:E6428-E6436. [PMID: 29941560 DOI: 10.1073/pnas.1802977115] [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] [Indexed: 11/18/2022] Open
Abstract
Transthyretin (TTR) is a globular tetrameric transport protein in plasma. Nearly 140 single amino acid substitutions in TTR cause life-threatening amyloid disease. We report a one-of-a-kind pathological variant featuring a Glu51, Ser52 duplication mutation (Glu51_Ser52dup). The proband, heterozygous for the mutation, exhibited an unusually aggressive amyloidosis that was refractory to treatment with the small-molecule drug diflunisal. To understand the poor treatment response and expand therapeutic options, we explored the structure and stability of recombinant Glu51_Ser52dup. The duplication did not alter the protein secondary or tertiary structure but decreased the stability of the TTR monomer and tetramer. Diflunisal, which bound with near-micromolar affinity, partially restored tetramer stability. The duplication had no significant effect on the free energy and enthalpy of diflunisal binding, and hence on the drug-protein interactions. However, the duplication induced tryptic digestion of TTR at near-physiological conditions, releasing a C-terminal fragment 49-129 that formed amyloid fibrils under conditions in which the full-length protein did not. Such C-terminal fragments, along with the full-length TTR, comprise amyloid deposits in vivo. Bioinformatics and structural analyses suggested that increased disorder in the surface loop, which contains the Glu51_Ser52dup duplication, not only helped generate amyloid-forming fragments but also decreased structural protection in the amyloidogenic residue segment 25-34, promoting misfolding of the full-length protein. Our studies of a unique duplication mutation explain its diflunisal-resistant nature, identify misfolding pathways for amyloidogenic TTR variants, and provide therapeutic targets to inhibit amyloid fibril formation by variant TTR.
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Kinetic analysis of the multistep aggregation pathway of human transthyretin. Proc Natl Acad Sci U S A 2018; 115:E6201-E6208. [PMID: 29915031 DOI: 10.1073/pnas.1807024115] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Aggregation of transthyretin (TTR) is the causative agent for TTR cardiomyopathy and polyneuropathy amyloidoses. Aggregation is initiated by dissociation of the TTR tetramer into a monomeric intermediate, which self-assembles into amyloid. The coupled multiple-step equilibria and low-concentration, aggregation-prone intermediates are challenging to probe using conventional assays. We report a 19F-NMR assay that leverages a highly sensitive trifluoroacetyl probe at a strategic site that gives distinct 19F chemical shifts for the TTR tetramer and monomeric intermediate and enables direct quantification of their populations during the aggregation process. Integration of real-time 19F-NMR and turbidity measurements as a function of temperature allows kinetic and mechanistic dissection of the aggregation pathway of both wild-type and mutant TTR. At physiological temperature, the monomeric intermediate formed by wild-type TTR under mildly acidic conditions rapidly aggregates into species that are invisible to NMR, leading to loss of the NMR signal at the same rate as the turbidity increase. Lower temperature accelerates tetramer dissociation and decelerates monomer tetramerization and oligomerization via reduced hydrophobic interactions associated with packing of a phenylalanine (F87) into a neighboring protomer. As a result, the intermediate accumulates to a higher level, and formation of higher-order aggregates is delayed. Application of this assay to pathogenic (V30M, L55P, and V122I) and protective (T119M) mutants revealed significant differences in behavior. A monomeric intermediate was observed only for V122I: aggregation of V30M and L55P proceeds without an observable monomeric intermediate, whereas the protective mutant T119M remains resistant to tetramer dissociation and aggregation.
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Westermark GT, Fändrich M, Lundmark K, Westermark P. Noncerebral Amyloidoses: Aspects on Seeding, Cross-Seeding, and Transmission. Cold Spring Harb Perspect Med 2018; 8:a024323. [PMID: 28108533 PMCID: PMC5749146 DOI: 10.1101/cshperspect.a024323] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
More than 30 proteins form amyloid in humans, most of them outside of the brain. Deposition of amyloid in extracerebral tissues is very common and seems inevitable for an aging person. Most deposits are localized, small, and probably without consequence, but in some instances, they are associated with diseases such as type 2 diabetes. Other extracerebral amyloidoses are systemic, with life-threatening effects on the heart, kidneys, and other organs. Here, we review how amyloid may spread through seeding and whether transmission of amyloid diseases may occur between humans. We also discuss whether cross-seeding is important in the development of amyloidosis, focusing specifically on the amyloid proteins AA, transthyretin, and islet amyloid polypeptide (IAPP).
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Affiliation(s)
- Gunilla T Westermark
- Department of Medical Cell Biology, Uppsala University, SE-751 23 Uppsala, Sweden
| | - Marcus Fändrich
- Institute of Protein Biochemistry, Ulm University, D-89081 Ulm, Germany
| | - Katarzyna Lundmark
- Department of Clinical Pathology and Clinical Genetics, and Department of Clinical and Experimental Medicine, Linköping University, SE-581 85 Linköping, Sweden
| | - Per Westermark
- Department of Immunology, Genetics and Pathology, Uppsala University, SE-751 85 Uppsala, Sweden
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Saldaño TE, Zanotti G, Parisi G, Fernandez-Alberti S. Evaluating the effect of mutations and ligand binding on transthyretin homotetramer dynamics. PLoS One 2017; 12:e0181019. [PMID: 28704493 PMCID: PMC5509292 DOI: 10.1371/journal.pone.0181019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 06/23/2017] [Indexed: 01/08/2023] Open
Abstract
Native transthyretin (TTR) homotetramer dissociation is the first step of the fibrils formation process in amyloid disease. A large number of specific point mutations that destabilize TTR quaternary structure have shown pro-amyloidogenic effects. Besides, several compounds have been proposed as drugs in the therapy of TTR amyloidosis due to their TTR tetramer binding affinities, and therefore, contribution to its integrity. In the present paper we have explored key positions sustaining TTR tetramer dynamical stability. We have identified positions whose mutations alter the most the TTR tetramer equilibrium dynamics based on normal mode analysis and their response to local perturbations. We have found that these positions are mostly localized at β-strands E and F and EF-loop. The monomer-monomer interface is pointed out as one of the most vulnerable regions to mutations that lead to significant changes in the TTR-tetramer equilibrium dynamics and, therefore, induces TTR amyloidosis. Besides, we have found that mutations on residues localized at the dimer-dimer interface and/or at the T4 hormone binding site destabilize the tetramer more than the average. Finally, we were able to compare several compounds according to their effect on vibrations associated to the ligand binding. Our ligand comparison is discussed and analyzed in terms of parameters and measurements associated to TTR-ligand binding affinities and the stabilization of its native state.
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Affiliation(s)
| | - Giuseppe Zanotti
- Department of Biomedical Science, University of Padua, Padova, Italy
| | - Gustavo Parisi
- Universidad Nacional de Quilmes/CONICET, Bernal, Argentina
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Andrei SA, Sijbesma E, Hann M, Davis J, O’Mahony G, Perry MWD, Karawajczyk A, Eickhoff J, Brunsveld L, Doveston RG, Milroy LG, Ottmann C. Stabilization of protein-protein interactions in drug discovery. Expert Opin Drug Discov 2017; 12:925-940. [DOI: 10.1080/17460441.2017.1346608] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Sebastian A. Andrei
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Eline Sijbesma
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Michael Hann
- Platform Technology and Science, Medicines Research Centre, GlaxoSmithKline R&D, Stevenage, UK
| | - Jeremy Davis
- Department of Chemistry, UCB Celltech, Slough, UK
| | - Gavin O’Mahony
- CVMD Medicinal Chemistry, Innovative Medicines and Early Development, AstraZeneca Gothenburg, Pepparedsleden, Mölndal, Sweden
| | - Matthew W. D. Perry
- RIA Medicinal Chemistry, Innovative Medicines and Early Development, AstraZeneca Gothenburg, Pepparedsleden, Mölndal, Sweden
| | - Anna Karawajczyk
- Medicinal Chemistry, Taros Chemicals GmbH & Co. KG, Dortmund, Germany
| | - Jan Eickhoff
- Assay development & screening, Lead Discovery Center GmbH, Dortmund, Germany
| | - Luc Brunsveld
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Richard G. Doveston
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Lech-Gustav Milroy
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Christian Ottmann
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
- Department of Chemistry, University of Duisburg-Essen, Essen, Germany
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36
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Sekijima Y, Campos RI, Hammarström P, Nilsson KPR, Yoshinaga T, Nagamatsu K, Yazaki M, Kametani F, Ikeda SI. Pathological, biochemical, and biophysical characteristics of the transthyretin variant Y114H (p.Y134H) explain its very mild clinical phenotype. J Peripher Nerv Syst 2016; 20:372-9. [PMID: 26306725 DOI: 10.1111/jns.12143] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 08/16/2015] [Accepted: 08/19/2015] [Indexed: 11/29/2022]
Abstract
Transthyretin (TTR) is a homotetrameric protein that must misfold in order to form amyloid fibrils. Misfolding includes rate limiting tetramer dissociation, followed by fast tertiary structural changes of the monomer that enable aggregation. Hereditary ATTR amyloidosis is an autosomal dominant genetic disorder with systemic deposition of amyloid fibrils induced by TTR gene mutation. We identified a rare Y114H (p.Y134H) TTR variant in a Japanese patient presenting with late-onset, very mild clinical course. The patient had an extremely low serum variant TTR concentration (18% of total TTR), whereas the composition of variant TTR was 55% in amyloid fibrils in tenosynovial tissues obtained at carpal tunnel release surgery. The amyloid fibril deposits in the ATTR Y114H patient had an altered structure compared with that in wild-type ATTR patients, as determined by luminescent conjugated poly/oligo-thiophene fluorescence spectroscopy. Biophysical studies using recombinant protein showed that Y114H TTR was markedly destabilized both thermodynamically and kinetically and was highly amyloidogenic in vitro. These data suggest that extremely low serum variant Y114H TTR concentration, probably due to endoplasmic reticulum-associated degradation of unstable variant TTR protein, protected this patient from severe amyloidosis, as self-assembly of the amyloidogenic intermediate is a concentration-dependent process.
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Affiliation(s)
- Yoshiki Sekijima
- Department of Medicine (Neurology and Rheumatology), Shinshu University School of Medicine, Matsumoto, Japan.,Institute for Biomedical Sciences, Shinshu University, Matsumoto, Japan
| | - Raúl I Campos
- IFM-Department of Chemistry, Linköping University, Linköping, Sweden
| | - Per Hammarström
- IFM-Department of Chemistry, Linköping University, Linköping, Sweden
| | - K Peter R Nilsson
- IFM-Department of Chemistry, Linköping University, Linköping, Sweden
| | - Tsuneaki Yoshinaga
- Department of Medicine (Neurology and Rheumatology), Shinshu University School of Medicine, Matsumoto, Japan
| | - Kiyoshiro Nagamatsu
- Department of Medicine (Neurology and Rheumatology), Shinshu University School of Medicine, Matsumoto, Japan
| | - Masahide Yazaki
- Department of Medicine (Neurology and Rheumatology), Shinshu University School of Medicine, Matsumoto, Japan.,Institute for Biomedical Sciences, Shinshu University, Matsumoto, Japan
| | - Fuyuki Kametani
- Tokyo Institute of Psychiatry, Tokyo Metropolitan Organization for Medical Research, Tokyo, Japan
| | - Shu-ichi Ikeda
- Department of Medicine (Neurology and Rheumatology), Shinshu University School of Medicine, Matsumoto, Japan.,Institute for Biomedical Sciences, Shinshu University, Matsumoto, Japan
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37
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Jesus CSH, Almeida ZL, Vaz DC, Faria TQ, Brito RMM. A New Folding Kinetic Mechanism for Human Transthyretin and the Influence of the Amyloidogenic V30M Mutation. Int J Mol Sci 2016; 17:E1428. [PMID: 27589730 PMCID: PMC5037707 DOI: 10.3390/ijms17091428] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 08/18/2016] [Accepted: 08/23/2016] [Indexed: 02/04/2023] Open
Abstract
Protein aggregation into insoluble amyloid fibrils is the hallmark of several neurodegenerative diseases, chief among them Alzheimer's and Parkinson's. Although caused by different proteins, these pathologies share some basic molecular mechanisms with familial amyloidotic polyneuropathy (FAP), a rare hereditary neuropathy caused by amyloid formation and deposition by transthyretin (TTR) in the peripheral and autonomic nervous systems. Among the amyloidogenic TTR mutations known, V30M-TTR is the most common in FAP. TTR amyloidogenesis (ATTR) is triggered by tetramer dissociation, followed by partial unfolding and aggregation of the low conformational stability monomers formed. Thus, tetramer dissociation kinetics, monomer conformational stability and competition between refolding and aggregation pathways do play a critical role in ATTR. Here, we propose a new model to analyze the refolding kinetics of WT-TTR and V30M-TTR, showing that at pH and protein concentrations close to physiological, a two-step mechanism with a unimolecular first step followed by a second-order second step adjusts well to the experimental data. Interestingly, although sharing the same kinetic mechanism, V30M-TTR refolds at a much slower rate than WT-TTR, a feature that may favor the formation of transient species leading to kinetic partition into amyloidogenic pathways and, thus, significantly increasing the probability of amyloid formation in vivo.
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Affiliation(s)
- Catarina S H Jesus
- Chemistry Department and Coimbra Chemistry Centre, Faculty of Science and Technology, University of Coimbra, Coimbra 3004-535, Portugal.
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra 3004-504, Portugal.
| | - Zaida L Almeida
- Chemistry Department and Coimbra Chemistry Centre, Faculty of Science and Technology, University of Coimbra, Coimbra 3004-535, Portugal.
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra 3004-504, Portugal.
| | - Daniela C Vaz
- Chemistry Department and Coimbra Chemistry Centre, Faculty of Science and Technology, University of Coimbra, Coimbra 3004-535, Portugal.
- Health Research Unit, School of Health Sciences, Leiria 2411-901, Portugal.
| | - Tiago Q Faria
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra 3004-504, Portugal.
| | - Rui M M Brito
- Chemistry Department and Coimbra Chemistry Centre, Faculty of Science and Technology, University of Coimbra, Coimbra 3004-535, Portugal.
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra 3004-504, Portugal.
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Systemic optimization and structural evaluation of quinoline derivatives as transthyretin amyloidogenesis inhibitors. Eur J Med Chem 2016; 123:777-787. [PMID: 27541261 DOI: 10.1016/j.ejmech.2016.08.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 08/02/2016] [Accepted: 08/04/2016] [Indexed: 12/12/2022]
Abstract
Wild type transthyretin (TTR) and mutant TTR misfold and misassemble into a variety of extracellular insoluble amyloid fibril and/or amorphous aggregate, which are associated with a variety of human amyloid diseases. To develop potent TTR amyloidogenesis inhibitors, we have designed and synthesized a focused library of quinoline derivatives by Pd-catalyzed coupling reaction and by the Horner-Wadsworth-Emmons reaction. The resulting 2-alkynylquinoline derivatives, (E)-2-alkenylquinoline derivatives, and (E)-3-alkenylquinoline derivatives were evaluated to inhibit TTR amyloidogenesis by utilizing the acid-mediated TTR fibril formation. Among these quinoline derivatives, compound 14c exhibited the most potent anti-TTR fibril formation activity in the screening studies, with IC50 values of 1.49 μM against WT-TTR and 1.63 μM against more amyloidogenic V30 M TTR mutant. That is comparable to that of approved therapeutic drug, tafamidis, to ameliorate transthyretin-related amyloidosis. Furthermore, rationalization of the increased efficacy of compound 14c bearing a hydrophobic substituent, such as chloride, was carried out by utilizing in silico docking study that could focus on the region of the thyroid hormone thyroxine (T4) binding sites. Additionally, the most potent compound 14c exhibited good pharmacokinetics properties. Taken together, the novel quinoline derivatives could potentially be explored as potential drug candidates to treat the human TTR amyloidosis.
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Kurian SM, Novais M, Whisenant T, Gelbart T, Buxbaum JN, Kelly JW, Coelho T, Salomon DR. Peripheral Blood Cell Gene Expression Diagnostic for Identifying Symptomatic Transthyretin Amyloidosis Patients: Male and Female Specific Signatures. Theranostics 2016; 6:1792-809. [PMID: 27570551 PMCID: PMC4997237 DOI: 10.7150/thno.14584] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 06/07/2016] [Indexed: 12/12/2022] Open
Abstract
Background: Early diagnosis of familial transthyretin (TTR) amyloid diseases remains challenging because of variable disease penetrance. Currently, patients must have an amyloid positive tissue biopsy to be eligible for disease-modifying therapies. Endomyocardial biopsies are typically amyloid positive when cardiomyopathy is suspected, but this disease manifestation is generally diagnosed late. Early diagnosis is often difficult because patients exhibit apparent symptoms of polyneuropathy, but have a negative amyloid biopsy. Thus, there is a pressing need for an additional early diagnostic strategy for TTR-aggregation-associated polyneuropathy and cardiomyopathy. Methods and Findings: Global peripheral blood cell mRNA expression profiles from 263 tafamidis-treated and untreated V30M Familiar Amyloid Neuropathy patients, asymptomatic V30M carriers, and healthy, age- and sex-matched controls without TTR mutations were used to differentiate symptomatic from asymptomatic patients. We demonstrate that blood cell gene expression patterns reveal sex-independent, as well as male- and female-specific inflammatory signatures in symptomatic FAP patients, but not in asymptomatic carriers. These signatures differentiated symptomatic patients from asymptomatic V30M carriers with >80% accuracy. There was a global downregulation of the eIF2 pathway and its associated genes in all symptomatic FAP patients. We also demonstrated that the molecular scores based on these signatures significantly trended toward normalized values in an independent cohort of 46 FAP patients after only 3 months of tafamidis treatment. Conclusions: This study identifies novel molecular signatures that differentiate symptomatic FAP patients from asymptomatic V30M carriers as well as affected males and females. We envision using this approach, initially in parallel with amyloid biopsies, to identify individuals who are asymptomatic gene carriers that may convert to FAP patients. Upon further validation, peripheral blood cell mRNA expression profiling could become an independent early diagnostic. This quantitative gene expression signature for symptomatic FAP could also become a biomarker to demonstrate significant disease-modifying effects of drugs and drug candidates. For example, when new disease modifiers are being evaluated in a FAP clinical trial, such surrogate biomarkers have the potential to provide an objective, quantitative and mechanistic molecular diagnostic of disease response to therapy.
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Higaki JN, Chakrabartty A, Galant NJ, Hadley KC, Hammerson B, Nijjar T, Torres R, Tapia JR, Salmans J, Barbour R, Tam SJ, Flanagan K, Zago W, Kinney GG. Novel conformation-specific monoclonal antibodies against amyloidogenic forms of transthyretin. Amyloid 2016; 23:86-97. [PMID: 26981744 PMCID: PMC4898150 DOI: 10.3109/13506129.2016.1148025] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Transthyretin amyloidosis (ATTR amyloidosis) is caused by the misfolding and deposition of the transthyretin (TTR) protein and results in progressive multi-organ dysfunction. TTR epitopes exposed by dissociation and misfolding are targets for immunotherapeutic antibodies. We developed and characterized antibodies that selectively bound to misfolded, non-native conformations of TTR. METHODS Antibody clones were generated by immunizing mice with an antigenic peptide comprising a cryptotope within the TTR sequence and screened for specific binding to non-native TTR conformations, suppression of in vitro TTR fibrillogenesis, promotion of antibody-dependent phagocytic uptake of mis-folded TTR and specific immunolabeling of ATTR amyloidosis patient-derived tissue. RESULTS Four identified monoclonal antibodies were characterized. These antibodies selectively bound the target epitope on monomeric and non-native misfolded forms of TTR and strongly suppressed TTR fibril formation in vitro. These antibodies bound fluorescently tagged aggregated TTR, targeting it for phagocytic uptake by macrophage THP-1 cells, and amyloid-positive TTR deposits in heart tissue from patients with ATTR amyloidosis, but did not bind to other types of amyloid deposits or normal tissue. CONCLUSIONS Conformation-specific anti-TTR antibodies selectively bind amyloidogenic but not native TTR. These novel antibodies may be therapeutically useful in preventing deposition and promoting clearance of TTR amyloid and in diagnosing TTR amyloidosis.
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Affiliation(s)
| | - Avi Chakrabartty
- b Princess Margaret Cancer Centre, University Health Network , Toronto , Ontario , Canada , and
| | - Natalie J Galant
- b Princess Margaret Cancer Centre, University Health Network , Toronto , Ontario , Canada , and
| | - Kevin C Hadley
- b Princess Margaret Cancer Centre, University Health Network , Toronto , Ontario , Canada , and
| | | | | | - Ronald Torres
- a Prothena Biosciences Inc , South San Francisco , CA , USA
| | - Jose R Tapia
- a Prothena Biosciences Inc , South San Francisco , CA , USA
| | - Joshua Salmans
- a Prothena Biosciences Inc , South San Francisco , CA , USA
| | - Robin Barbour
- a Prothena Biosciences Inc , South San Francisco , CA , USA
| | - Stephen J Tam
- a Prothena Biosciences Inc , South San Francisco , CA , USA
| | - Ken Flanagan
- a Prothena Biosciences Inc , South San Francisco , CA , USA
| | - Wagner Zago
- a Prothena Biosciences Inc , South San Francisco , CA , USA
| | - Gene G Kinney
- a Prothena Biosciences Inc , South San Francisco , CA , USA
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41
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Mangrolia P, Yang DT, Murphy RM. Transthyretin variants with improved inhibition of β-amyloid aggregation. Protein Eng Des Sel 2016; 29:209-218. [PMID: 27099354 DOI: 10.1093/protein/gzw008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 03/08/2016] [Indexed: 01/18/2023] Open
Abstract
Aggregation of β-amyloid (Aβ) is widely believed to cause neuronal dysfunction in Alzheimer's disease. Transthyretin (TTR) binds to Aβ and inhibits its aggregation and neurotoxicity. TTR is a homotetrameric protein, with each monomer containing a short α-helix and two anti-parallel β-sheets. Dimers pack into tetramers to form a hydrophobic cavity. Here we report the discovery of a TTR mutant, N98A, that was more effective at inhibiting Aβ aggregation than wild-type (WT) TTR, although N98A and WT bound Aβ equally. The N98A mutation is located on a flexible loop distant from the putative Aβ-binding sites and does not alter secondary and tertiary structures nor prevent correct assembly into tetramers. Under non-physiological conditions, N98A tetramers were kinetically and thermodynamically less stable than WT, suggesting a difference in the tetramer folded structure. In vivo, the lone cysteine in TTR is frequently modified by S-cysteinylation or S-sulfonation. Like the N98A mutation, S-cysteinylation of TTR modestly decreased tetramer stability and increased TTR's effectiveness at inhibiting Aβ aggregation. Collectively, these data indicate that a subtle change in TTR tetramer structure measurably increases TTR's ability to inhibit Aβ aggregation.
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Affiliation(s)
- Parth Mangrolia
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Dr., Madison, WI 53706, USA
| | - Dennis T Yang
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Dr., Madison, WI 53706, USA
| | - Regina M Murphy
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, 1415 Engineering Dr., Madison, WI 53706, USA
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42
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Baranczak A, Kelly JW. A current pharmacologic agent versus the promise of next generation therapeutics to ameliorate protein misfolding and/or aggregation diseases. Curr Opin Chem Biol 2016; 32:10-21. [PMID: 26859714 DOI: 10.1016/j.cbpa.2016.01.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 01/14/2016] [Accepted: 01/14/2016] [Indexed: 12/18/2022]
Abstract
The list of protein aggregation-associated degenerative diseases is long and growing, while the portfolio of disease-modifying strategies is very small. In this review and perspective, we assess what has worked to slow the progression of an aggregation-associated degenerative disease, covering the underlying mechanism of pharmacologic action and what we have learned about the etiology of the transthyretin amyloid diseases and likely amyloidoses in general. Next, we introduce emerging therapies that should apply more generally to protein misfolding and/or aggregation diseases, approaches that rely on adapting the protein homeostasis or proteostasis network for disease amelioration.
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Affiliation(s)
- Aleksandra Baranczak
- Department of Chemistry and The Skaggs Institute for Chemical Biology, La Jolla, CA 92037, USA; Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | - Jeffery W Kelly
- Department of Chemistry and The Skaggs Institute for Chemical Biology, La Jolla, CA 92037, USA; Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
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43
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Broom HR, Vassall KA, Rumfeldt JAO, Doyle CM, Tong MS, Bonner JM, Meiering EM. Combined Isothermal Titration and Differential Scanning Calorimetry Define Three-State Thermodynamics of fALS-Associated Mutant Apo SOD1 Dimers and an Increased Population of Folded Monomer. Biochemistry 2016; 55:519-33. [PMID: 26710831 DOI: 10.1021/acs.biochem.5b01187] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Many proteins are naturally homooligomers, homodimers most frequently. The overall stability of oligomeric proteins may be described in terms of the stability of the constituent monomers and the stability of their association; together, these stabilities determine the populations of different monomer and associated species, which generally have different roles in the function or dysfunction of the protein. Here we show how a new combined calorimetry approach, using isothermal titration calorimetry to define monomer association energetics together with differential scanning calorimetry to measure total energetics of oligomer unfolding, can be used to analyze homodimeric unmetalated (apo) superoxide dismutase (SOD1) and determine the effects on the stability of structurally diverse mutations associated with amyotrophic lateral sclerosis (ALS). Despite being located throughout the protein, all mutations studied weaken the dimer interface, while concomitantly either decreasing or increasing the marginal stability of the monomer. Analysis of the populations of dimer, monomer, and unfolded monomer under physiological conditions of temperature, pH, and protein concentration shows that all mutations promote the formation of folded monomers. These findings may help rationalize the key roles proposed for monomer forms of SOD1 in neurotoxic aggregation in ALS, as well as roles for other forms of SOD1. Thus, the results obtained here provide a valuable approach for the quantitative analysis of homooligomeric protein stabilities, which can be used to elucidate the natural and aberrant roles of different forms of these proteins and to improve methods for predicting protein stabilities.
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Affiliation(s)
- Helen R Broom
- Department of Chemistry, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada
| | - Kenrick A Vassall
- Department of Chemistry, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada
| | - Jessica A O Rumfeldt
- Department of Chemistry, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada
| | - Colleen M Doyle
- Department of Chemistry, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada
| | - Ming Sze Tong
- Department of Chemistry, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada
| | - Julia M Bonner
- Department of Chemistry, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada
| | - Elizabeth M Meiering
- Department of Chemistry, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada
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Eisele YS, Monteiro C, Fearns C, Encalada SE, Wiseman RL, Powers ET, Kelly JW. Targeting protein aggregation for the treatment of degenerative diseases. Nat Rev Drug Discov 2015; 14:759-80. [PMID: 26338154 PMCID: PMC4628595 DOI: 10.1038/nrd4593] [Citation(s) in RCA: 278] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The aggregation of specific proteins is hypothesized to underlie several degenerative diseases, which are collectively known as amyloid disorders. However, the mechanistic connection between the process of protein aggregation and tissue degeneration is not yet fully understood. Here, we review current and emerging strategies to ameliorate aggregation-associated degenerative disorders, with a focus on disease-modifying strategies that prevent the formation of and/or eliminate protein aggregates. Persuasive pharmacological and genetic evidence now supports protein aggregation as the cause of postmitotic tissue dysfunction or loss. However, a more detailed understanding of the factors that trigger and sustain aggregate formation and of the structure-activity relationships underlying proteotoxicity is needed to develop future disease-modifying therapies.
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Affiliation(s)
- Yvonne S. Eisele
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Cecilia Monteiro
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Colleen Fearns
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Sandra E. Encalada
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
- Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California 92037, USA
- Department of Molecular and Cellular Neuroscience, The Scripps Research Institute, La Jolla, California 92037, USA
| | - R. Luke Wiseman
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Evan T. Powers
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Jeffery W. Kelly
- Department of Chemistry, The Scripps Research Institute, La Jolla, California 92037, USA
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California 92037, USA
- The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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Florio P, Folli C, Cianci M, Del Rio D, Zanotti G, Berni R. Transthyretin Binding Heterogeneity and Anti-amyloidogenic Activity of Natural Polyphenols and Their Metabolites. J Biol Chem 2015; 290:29769-80. [PMID: 26468275 DOI: 10.1074/jbc.m115.690172] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Indexed: 12/11/2022] Open
Abstract
Transthyretin (TTR) is an amyloidogenic protein, the amyloidogenic potential of which is enhanced by a number of specific point mutations. The ability to inhibit TTR fibrillogenesis is known for several classes of compounds, including natural polyphenols, which protect the native state of TTR by specifically interacting with its thyroxine binding sites. Comparative analyses of the interaction and of the ability to protect the TTR native state for polyphenols, both stilbenoids and flavonoids, and some of their main metabolites have been carried out. A main finding of this investigation was the highly preferential binding of resveratrol and thyroxine, both characterized by negative binding cooperativity, to distinct sites in TTR, consistent with the data of x-ray analysis of TTR in complex with both ligands. Although revealing the ability of the two thyroxine binding sites of TTR to discriminate between different ligands, this feature has allowed us to evaluate the interactions of polyphenols with both resveratrol and thyroxine preferential binding sites, by using resveratrol and radiolabeled T4 as probes. Among flavonoids, genistein and apigenin were able to effectively displace resveratrol from its preferential binding site, whereas genistein also showed the ability to interact, albeit weakly, with the preferential thyroxine binding site. Several glucuronidated polyphenol metabolites did not exhibit significant competition for resveratrol and thyroxine preferential binding sites and lacked the ability to stabilize TTR. However, resveratrol-3-O-sulfate was able to significantly protect the protein native state. A rationale for the in vitro properties found for polyphenol metabolites was provided by x-ray analysis of their complexes with TTR.
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Affiliation(s)
- Paola Florio
- From the Department of Life Sciences, University of Parma, 43124 Parma, Italy
| | - Claudia Folli
- the Department of Food Science, University of Parma, 43124 Parma, Italy
| | - Michele Cianci
- the European Molecular Biology Laboratory, 22607 Hamburg, Germany, and
| | - Daniele Del Rio
- the Department of Food Science, University of Parma, 43124 Parma, Italy
| | - Giuseppe Zanotti
- the Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy
| | - Rodolfo Berni
- From the Department of Life Sciences, University of Parma, 43124 Parma, Italy,
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Saelices L, Johnson LM, Liang WY, Sawaya MR, Cascio D, Ruchala P, Whitelegge J, Jiang L, Riek R, Eisenberg DS. Uncovering the Mechanism of Aggregation of Human Transthyretin. J Biol Chem 2015; 290:28932-43. [PMID: 26459562 PMCID: PMC4661406 DOI: 10.1074/jbc.m115.659912] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Indexed: 11/06/2022] Open
Abstract
The tetrameric thyroxine transport protein transthyretin (TTR) forms amyloid fibrils upon dissociation and monomer unfolding. The aggregation of transthyretin has been reported as the cause of the life-threatening transthyretin amyloidosis. The standard treatment of familial cases of TTR amyloidosis has been liver transplantation. Although aggregation-preventing strategies involving ligands are known, understanding the mechanism of TTR aggregation can lead to additional inhibition approaches. Several models of TTR amyloid fibrils have been proposed, but the segments that drive aggregation of the protein have remained unknown. Here we identify β-strands F and H as necessary for TTR aggregation. Based on the crystal structures of these segments, we designed two non-natural peptide inhibitors that block aggregation. This work provides the first characterization of peptide inhibitors for TTR aggregation, establishing a novel therapeutic strategy.
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Affiliation(s)
- Lorena Saelices
- From the Department of Biological Chemistry, Department of Chemistry and Biochemistry, and Howard Hughes Medical Institute, UCLA, Los Angeles, California 90095-1570, Swiss Federal Institute of Technology in Zürich (ETH), Physical Chemistry, ETH Hönggerberg, 8093 Zürich, Switzerland, and
| | - Lisa M Johnson
- From the Department of Biological Chemistry, Department of Chemistry and Biochemistry, and Howard Hughes Medical Institute, UCLA, Los Angeles, California 90095-1570
| | - Wilson Y Liang
- From the Department of Biological Chemistry, Department of Chemistry and Biochemistry, and Howard Hughes Medical Institute, UCLA, Los Angeles, California 90095-1570
| | - Michael R Sawaya
- From the Department of Biological Chemistry, Department of Chemistry and Biochemistry, and Howard Hughes Medical Institute, UCLA, Los Angeles, California 90095-1570
| | - Duilio Cascio
- From the Department of Biological Chemistry, Department of Chemistry and Biochemistry, and Howard Hughes Medical Institute, UCLA, Los Angeles, California 90095-1570
| | - Piotr Ruchala
- the Department of Psychiatry and Biobehavioral Sciences, UCLA and The Pasarow Mass Spectrometry Laboratory, The Jane and Terry Semel Institute for Neuroscience and Human Behavior, Los Angeles, California 90024
| | - Julian Whitelegge
- the Department of Psychiatry and Biobehavioral Sciences, UCLA and The Pasarow Mass Spectrometry Laboratory, The Jane and Terry Semel Institute for Neuroscience and Human Behavior, Los Angeles, California 90024
| | - Lin Jiang
- From the Department of Biological Chemistry, Department of Chemistry and Biochemistry, and Howard Hughes Medical Institute, UCLA, Los Angeles, California 90095-1570
| | - Roland Riek
- Swiss Federal Institute of Technology in Zürich (ETH), Physical Chemistry, ETH Hönggerberg, 8093 Zürich, Switzerland, and
| | - David S Eisenberg
- From the Department of Biological Chemistry, Department of Chemistry and Biochemistry, and Howard Hughes Medical Institute, UCLA, Los Angeles, California 90095-1570,
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Pagano RS, López Medus M, Gómez GE, Couto PM, Labanda MS, Landolfo L, D'Alessio C, Caramelo JJ. Protein fibrillation lag times during kinetic inhibition. Biophys J 2015; 107:711-720. [PMID: 25099810 DOI: 10.1016/j.bpj.2014.06.029] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 06/03/2014] [Accepted: 06/18/2014] [Indexed: 12/14/2022] Open
Abstract
Protein aggregation is linked to more than 30 human pathologies, including Alzheimer's and Parkinson's diseases. Since small oligomers that form at the beginning of the fibrillation process probably are the most toxic elements, therapeutic strategies involving fibril fragmentation could be detrimental. An alternative approach, named kinetic inhibition, aims to prevent fibril formation by using small ligands that stabilize the parent protein. The factors that govern fibrillation lag times during kinetic inhibition are largely unknown, notwithstanding their importance for designing effective long-term therapies. Inhibitor-bound species are not likely to be incorporated into the core of mature fibrils, although their presence could alter the kinetics of the fibrillation process. For instance, inhibitor-bound species may act as capping elements that impair the nucleation process and/or fibril growth. Here, we address this issue by studying the effect of two natural inhibitors on the fibrillation behavior of lysozyme at neutral pH. We analyzed a set of 79 fibrillation curves obtained in lysozyme alone and a set of 37 obtained in the presence of inhibitors. We calculated the concentrations of the relevant species at the beginning of the curves using the inhibitor-binding constants measured under the same experimental conditions. We found that inhibitor-bound protein species do not affect fibrillation onset times, which are mainly determined by the concentration of unbound protein species present in equilibrium. In this system, knowledge of the fibrillation kinetics and inhibitor affinities suffices to predict the effect of kinetic inhibitors on fibrillation lag times. In addition, we developed a new methodology to better estimate fibrillation lag times from experimental curves.
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Affiliation(s)
- Rodrigo S Pagano
- Structural Cell Biology Laboratory, Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Buenos Aires, Argentina
| | - Máximo López Medus
- Structural Cell Biology Laboratory, Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Buenos Aires, Argentina
| | - Gabriela E Gómez
- Department of Biological Chemistry, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina
| | - Paula M Couto
- Structural Cell Biology Laboratory, Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Buenos Aires, Argentina
| | - María S Labanda
- Structural Cell Biology Laboratory, Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Buenos Aires, Argentina
| | - Lucas Landolfo
- Structural Cell Biology Laboratory, Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Buenos Aires, Argentina
| | - Cecilia D'Alessio
- Laboratory of Glycobiology, Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Buenos Aires, Argentina; Department of Physiology and Molecular Biology, University of Buenos Aires, Buenos Aires, Argentina
| | - Julio J Caramelo
- Structural Cell Biology Laboratory, Fundación Instituto Leloir and Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA-CONICET), Buenos Aires, Argentina; Department of Biological Chemistry, School of Sciences, University of Buenos Aires, Buenos Aires, Argentina.
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48
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Cianci M, Folli C, Zonta F, Florio P, Berni R, Zanotti G. Structural evidence for asymmetric ligand binding to transthyretin. ACTA ACUST UNITED AC 2015; 71:1582-92. [DOI: 10.1107/s1399004715010585] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 06/01/2015] [Indexed: 12/22/2022]
Abstract
Human transthyretin (TTR) represents a notable example of an amyloidogenic protein, and several compounds that are able to stabilize its native state have been proposed as effective drugs in the therapy of TTR amyloidosis. The two thyroxine (T4) binding sites present in the TTR tetramer display negative binding cooperativity. Here, structures of TTR in complex with three natural polyphenols (pterostilbene, quercetin and apigenin) have been determined, in which this asymmetry manifests itself as the presence of a main binding site with clear ligand occupancy and related electron density and a second minor site with a much lower ligand occupancy. The results of an analysis of the structural differences between the two binding sites are consistent with such a binding asymmetry. The different ability of TTR ligands to saturate the two T4 binding sites of the tetrameric protein can be ascribed to the different affinity of ligands for the weaker binding site. In comparison, the high-affinity ligand tafamidis, co-crystallized under the same experimental conditions, was able to fully saturate the two T4 binding sites. This asymmetry is characterized by the presence of small but significant differences in the conformation of the cavity of the two binding sites. Molecular-dynamics simulations suggest the presence of even larger differences in solution. Competition binding assays carried out in solution revealed the presence of a preferential binding site in TTR for the polyphenols pterostilbene and quercetin that was different from the preferential binding site for T4. The TTR binding asymmetry could possibly be exploited for the therapy of TTR amyloidosis by using a cocktail of two drugs, each of which exhibits preferential binding for a distinct binding site, thus favouring saturation of the tetrameric protein and consequently its stabilization.
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Patra M, Mukhopadhyay C, Chakrabarti A. Probing conformational stability and dynamics of erythroid and nonerythroid spectrin: effects of urea and guanidine hydrochloride. PLoS One 2015; 10:e0116991. [PMID: 25617632 PMCID: PMC4305312 DOI: 10.1371/journal.pone.0116991] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 12/18/2014] [Indexed: 11/19/2022] Open
Abstract
We have studied the conformational stability of the two homologous membrane skeletal proteins, the erythroid and non-erythroid spectrins, in their dimeric and tetrameric forms respectively during unfolding in the presence of urea and guanidine hydrochloride (GuHCl). Fluorescence and circular dichroism (CD) spectroscopy have been used to study the changes of intrinsic tryptophan fluorescence, anisotropy, far UV-CD and extrinsic fluorescence of bound 1-anilinonapthalene-8-sulfonic acid (ANS). Chemical unfolding of both proteins were reversible and could be described as a two state transition. The folded erythroid spectrin and non-erythroid spectrin were directly converted to unfolded monomer without formation of any intermediate. Fluorescence quenching, anisotropy, ANS binding and dynamic light scattering data suggest that in presence of low concentrations of the denaturants (up-to 1M) hydrogen bonding network and van der Waals interaction play a role inducing changes in quaternary as well as tertiary structures without complete dissociation of the subunits. This is the first report of two large worm like, multi-domain proteins obeying twofold rule which is commonly found in small globular proteins. The free energy of stabilization (ΔGuH20) for the dimeric spectrin has been 20 kcal/mol lesser than the tetrameric from.
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Affiliation(s)
- Malay Patra
- Chemistry Department, University of Calcutta, Kolkata, West Bengal, India
| | | | - Abhijit Chakrabarti
- Crystallography & Molecular Biology Division, Saha Institute of Nuclear Physics, Kolkata, West Bengal, India
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50
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Grimm FA, Lehmler HJ, He X, Robertson LW, Duffel MW. Modulating inhibitors of transthyretin fibrillogenesis via sulfation: polychlorinated biphenyl sulfates as models. Chem Biol Interact 2015; 228:1-8. [PMID: 25595224 DOI: 10.1016/j.cbi.2015.01.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 12/15/2014] [Accepted: 01/02/2015] [Indexed: 11/25/2022]
Abstract
Small molecules that bind with high affinity to thyroxine (T4) binding sites on transthyretin (TTR) kinetically stabilize the protein's tetrameric structure, thereby efficiently decreasing the rate of tetramer dissociation in TTR related amyloidoses. Current research efforts aim to optimize the amyloid inhibiting properties of known inhibitors, such as derivatives of biphenyls, dibenzofurans and benzooxazoles, by chemical modification. In order to test the hypothesis that sulfate group substituents can improve the efficiencies of such inhibitors, we evaluated the potential of six polychlorinated biphenyl sulfates to inhibit TTR amyloid fibril formation in vitro. In addition, we determined their binding orientations and molecular interactions within the T4 binding site by molecular docking simulations. Utilizing this combined experimental and computational approach, we demonstrated that sulfation significantly improves the amyloid inhibiting properties as compared to both parent and hydroxylated PCBs. Importantly, several PCB sulfates were of equal or higher potency than some of the most effective previously described inhibitors.
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Affiliation(s)
- Fabian A Grimm
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, USA; Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, The University of Iowa, Iowa City, IA, USA
| | - Hans-Joachim Lehmler
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, USA; Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, USA
| | - Xianran He
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, USA
| | - Larry W Robertson
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, USA; Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, Iowa City, IA, USA
| | - Michael W Duffel
- Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA, USA; Department of Pharmaceutical Sciences and Experimental Therapeutics, College of Pharmacy, The University of Iowa, Iowa City, IA, USA.
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