1
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Ciccone L, Camodeca C, Tonali N, Barlettani L, Rossello A, Fruchart Gaillard C, Kaffy J, Petrarolo G, La Motta C, Nencetti S, Orlandini E. New Hybrid Compounds Incorporating Natural Products as Multifunctional Agents against Alzheimer's Disease. Pharmaceutics 2023; 15:2369. [PMID: 37896129 PMCID: PMC10610016 DOI: 10.3390/pharmaceutics15102369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 09/06/2023] [Accepted: 09/15/2023] [Indexed: 10/29/2023] Open
Abstract
A series of new hybrid derivatives 1a-c, 2a-c, 3a-c, 4a-c, 5a-c, inspired by nature, were synthesized and studied as multifunctional agents for the treatment of Alzheimer's disease (AD). These compounds were designed to merge together the trifluoromethyl benzyloxyaminic bioactive moiety, previously identified, with different acids available in nature. The ability of the synthesized compounds to chelate biometals, such as Cu2+, Zn2+ and Fe2+, was studied by UV-Vis spectrometer, and through a preliminary screening their antioxidant activity was evaluated by DPPH. Then, selected compounds were tested by in vitro ABTS free radical method and ex vivo rat brain TBARS assay. Compounds 2a-c, combining the strongest antioxidant and biometal chelators activities, were studied for their ability to contrast Aβ1-40 fibrillization process. Finally, starting from the promising profile obtained for compound 2a, we evaluated if it could be able to induce a positive cross-interaction between transthyretin (TTR) and Aβ in presence and in absence of Cu2+.
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Affiliation(s)
- Lidia Ciccone
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy; (C.C.); (L.B.); (A.R.); (G.P.); (C.L.M.)
| | - Caterina Camodeca
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy; (C.C.); (L.B.); (A.R.); (G.P.); (C.L.M.)
| | - Nicolò Tonali
- CNRS, BioCIS, Bâtiment Henri Moissan, Université Paris-Saclay, 17 Av. des Sciences, 91400 Orsay, France; (N.T.); (J.K.)
| | - Lucia Barlettani
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy; (C.C.); (L.B.); (A.R.); (G.P.); (C.L.M.)
| | - Armando Rossello
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy; (C.C.); (L.B.); (A.R.); (G.P.); (C.L.M.)
- Research Center “E. Piaggio”, University of Pisa, 56122 Pisa, Italy;
| | - Carole Fruchart Gaillard
- CEA, INRAE, Département Médicaments et Technologies pour la Santé (DMTS), SIMoS, Université Paris Saclay, 91191 Gif-sur-Yvette, France;
| | - Julia Kaffy
- CNRS, BioCIS, Bâtiment Henri Moissan, Université Paris-Saclay, 17 Av. des Sciences, 91400 Orsay, France; (N.T.); (J.K.)
| | - Giovanni Petrarolo
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy; (C.C.); (L.B.); (A.R.); (G.P.); (C.L.M.)
| | - Concettina La Motta
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy; (C.C.); (L.B.); (A.R.); (G.P.); (C.L.M.)
| | - Susanna Nencetti
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy; (C.C.); (L.B.); (A.R.); (G.P.); (C.L.M.)
| | - Elisabetta Orlandini
- Research Center “E. Piaggio”, University of Pisa, 56122 Pisa, Italy;
- Department of Earth Sciences, University of Pisa, Via Santa Maria 53, 56126 Pisa, Italy
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2
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Prokaeva T, Klimtchuk ES, Feschenko P, Spencer B, Cui H, Burks EJ, Aslebagh R, Muneeruddin K, Shaffer SA, Varghese E, Berk JL, Connors LH. An additive destabilising effect of compound T60I and V122I substitutions in ATTRv amyloidosis. Amyloid 2022:1-12. [PMID: 36286264 DOI: 10.1080/13506129.2022.2135988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
BACKGROUND The amyloidogenic transthyretin (TTR) variant, V122I, occurs in 4% of the African American population and frequently presents as a restricted cardiomyopathy. While heterozygosity for TTR V122I predominates, several compound heterozygous cases have been previously described. Herein, we detail features of ATTRv amyloidosis associated with novel compound heterozygous TTR mutation, T60I/V122I and provide evidence supporting the amyloidogenecity of T60I. METHODS A 63-year-old African American female presented with atrial fibrillation, congestive heart failure, autonomic and peripheral neuropathy. In vitro studies of TTR T60I and V122I were undertaken to compare the biophysical properties of the proteins. RESULTS Congophilic deposits in a rectal biopsy were immunohistochemically positive for TTR. Serum screening by isoelectric focussing revealed two TTR variants in the absence of wild-type protein. DNA sequencing identified compound heterozygous TTR gene mutations, c.239C > T and c.424G > A. Adipose amyloid deposits were composed of both T60I and V122I. While kinetic stabilities of T60I and V122I variants were similar, distinct thermodynamic stabilities and amyloid growth kinetics were observed. CONCLUSIONS This report provides clinical and experimental results supporting the amyloidogenic nature of a novel TTR T60I variant. In vitro data indicate that the destabilising effect of individual T60I and V122I variants appears to be additive rather than synergistic.
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Affiliation(s)
- Tatiana Prokaeva
- Amyloidosis Center, Boston University School of Medicine, Boston, MA, USA
| | - Elena S Klimtchuk
- Amyloidosis Center, Boston University School of Medicine, Boston, MA, USA
| | - Polina Feschenko
- Amyloidosis Center, Boston University School of Medicine, Boston, MA, USA
| | - Brian Spencer
- Amyloidosis Center, Boston University School of Medicine, Boston, MA, USA
| | - Haili Cui
- Amyloidosis Center, Boston University School of Medicine, Boston, MA, USA
| | - Eric J Burks
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, MA, USA
| | - Roshanak Aslebagh
- Mass Spectrometry Facility, University of Massachusetts Medical School, Shrewsbury, MA, USA.,Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Khaja Muneeruddin
- Mass Spectrometry Facility, University of Massachusetts Medical School, Shrewsbury, MA, USA.,Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Scott A Shaffer
- Mass Spectrometry Facility, University of Massachusetts Medical School, Shrewsbury, MA, USA.,Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Elizabeth Varghese
- Amyloidosis Center, Boston University School of Medicine, Boston, MA, USA
| | - John L Berk
- Amyloidosis Center, Boston University School of Medicine, Boston, MA, USA
| | - Lawreen H Connors
- Amyloidosis Center, Boston University School of Medicine, Boston, MA, USA.,Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, MA, USA
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3
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Tasaki M, Lavatelli F, Obici L, Obayashi K, Miyamoto T, Merlini G, Palladini G, Ando Y, Ueda M. Age-related amyloidosis outside the brain: A state-of-the-art review. Ageing Res Rev 2021; 70:101388. [PMID: 34116224 DOI: 10.1016/j.arr.2021.101388] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/26/2021] [Accepted: 06/04/2021] [Indexed: 02/01/2023]
Abstract
Inside and outside the brain, accumulation of amyloid fibrils plays key roles in the pathogenesis of fatal age-related diseases such as Alzheimer's and Parkinson's diseases and wild-type transthyretin amyloidosis. Although the incidence of all amyloidoses increases with age, for some types of amyloidosis aging is known as the main direct risk factor, and these types are typically diseases of elderly people. More than 10 different precursor proteins are known to cause age-associated amyloidosis; these proteins include amyloid β protein, α-synuclein, transthyretin, islet amyloid polypeptide, atrial natriuretic factor, and the newly discovered epidermal growth factor-containing fibulin-like extracellular matrix protein 1. Except for intracerebral amyloidoses, most age-related amyloidoses have been little studied. Indeed, in view of the increasing life expectancy in our societies, understanding how aging is involved in the process of amyloid fibril accumulation and the effects of amyloid deposits on the aging body is extremely important. In this review, we summarize current knowledge about the nature of amyloid precursor proteins, the prevalence, clinical manifestations, and pathogenesis of amyloidosis, and recent advances in our understanding of age-related amyloidoses outside the brain.
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4
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Cotrina EY, Vilà M, Nieto J, Arsequell G, Planas A. Preparative Scale Production of Recombinant Human Transthyretin for Biophysical Studies of Protein-Ligand and Protein-Protein Interactions. Int J Mol Sci 2020; 21:ijms21249640. [PMID: 33348885 PMCID: PMC7766448 DOI: 10.3390/ijms21249640] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 12/14/2020] [Accepted: 12/16/2020] [Indexed: 12/19/2022] Open
Abstract
Human transthyretin (hTTR), a serum protein with a main role in transporting thyroid hormones and retinol through binding to the retinol-binding protein, is an amyloidogenic protein involved in familial amyloidotic polyneuropathy (FAP), familial amyloidotic cardiomyopathy, and central nervous system selective amyloidosis. hTTR also has a neuroprotective role in Alzheimer disease, being the major Aβ binding protein in human cerebrospinal fluid (CSF) that prevents amyloid-β (Aβ) aggregation with consequent abrogation of toxicity. Here we report an optimized preparative expression and purification protocol of hTTR (wt and amyloidogenic mutants) for in vitro screening assays of TTR ligands acting as amyloidogenesis inhibitors or acting as molecular chaperones to enhance the TTR:Aβ interaction. Preparative yields were up to 660 mg of homogenous protein per L of culture in fed-batch bioreactor. The recombinant wt protein is mainly unmodified at Cys10, the single cysteine in the protein sequence, whereas the highly amyloidogenic Y78F variant renders mainly the S-glutathionated form, which has essentially the same amyloidogenic behavior than the reduced protein with free Cys10. The TTR production protocol has shown inter-batch reproducibility of expression and protein quality for in vitro screening assays.
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Affiliation(s)
- Ellen Y. Cotrina
- Laboratory of Biochemistry, Institut Químic de Sarrià, Universitat Ramon Llull, 08017 Barcelona, Spain; (E.Y.C.); (M.V.); (J.N.)
- Institut de Química Avançada de Catalunya, Consejo Superior de Investigaciones Científicas (IQAC-CSIC), 08034 Barcelona, Spain;
| | - Marta Vilà
- Laboratory of Biochemistry, Institut Químic de Sarrià, Universitat Ramon Llull, 08017 Barcelona, Spain; (E.Y.C.); (M.V.); (J.N.)
| | - Joan Nieto
- Laboratory of Biochemistry, Institut Químic de Sarrià, Universitat Ramon Llull, 08017 Barcelona, Spain; (E.Y.C.); (M.V.); (J.N.)
| | - Gemma Arsequell
- Institut de Química Avançada de Catalunya, Consejo Superior de Investigaciones Científicas (IQAC-CSIC), 08034 Barcelona, Spain;
| | - Antoni Planas
- Laboratory of Biochemistry, Institut Químic de Sarrià, Universitat Ramon Llull, 08017 Barcelona, Spain; (E.Y.C.); (M.V.); (J.N.)
- Correspondence:
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5
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Poltash ML, Shirzadeh M, McCabe JW, Moghadamchargari Z, Laganowsky A, Russell DH. New insights into the metal-induced oxidative degradation pathways of transthyretin. Chem Commun (Camb) 2019; 55:4091-4094. [PMID: 30887985 PMCID: PMC6452628 DOI: 10.1039/c9cc00682f] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The amyloidogenic mechanism of transthyretin is still debated but understanding it fully could lend insight into disease progression and potential therapeutics. Transthyretin was investigated revealing a metal-induced (Cr/Cu) oxidation pathway leading to N-terminal backbone fragmentation and oligomer formation; previously hidden details were revealed only by FT-IM-Orbitrap MS and surface-induced dissociation.
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Affiliation(s)
- Michael L Poltash
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, USA.
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6
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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: 28] [Impact Index Per Article: 4.7] [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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7
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Lavatelli F, di Fonzo A, Palladini G, Merlini G. Systemic amyloidoses and proteomics: The state of the art. EUPA OPEN PROTEOMICS 2016; 11:4-10. [PMID: 29900105 PMCID: PMC5988550 DOI: 10.1016/j.euprot.2016.02.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 02/01/2016] [Accepted: 02/16/2016] [Indexed: 12/11/2022]
Abstract
Proteomics is an established approach for diagnostic amyloid typing. Mass spectrometry-based methods to analyze amyloid precursors have been developed. Proteomic studies are ongoing to identify novel biomarkers and clarify disease mechanisms.
Systemic amyloidoses are caused by misfolding-prone proteins that polymerize in tissues, causing organ dysfunction. Since proteins are etiological agents of these diseases, proteomics was soon recognized as a privileged instrument for their investigation. Mass spectrometry-based proteomics has acquired a fundamental role in management of systemic amyloidoses, being now considered a gold standard approach for amyloid typing. In parallel, approaches for analyzing circulating amyloid precursors have been developed. Moreover, differential and functional proteomics hold promise for identifying novel biomarkers and clarifying disease mechanisms. This review discusses recent proteomics achievements in systemic amyloidoses, providing a perspective on its present and future applications.
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Affiliation(s)
- Francesca Lavatelli
- Amyloidosis Research and Treatment Center and Department of Molecular Medicine, Fondazione IRCCS Policlinico San Matteo and University of Pavia, Pavia, Italy
| | - Andrea di Fonzo
- Amyloidosis Research and Treatment Center and Department of Molecular Medicine, Fondazione IRCCS Policlinico San Matteo and University of Pavia, Pavia, Italy
| | - Giovanni Palladini
- Amyloidosis Research and Treatment Center and Department of Molecular Medicine, Fondazione IRCCS Policlinico San Matteo and University of Pavia, Pavia, Italy
| | - Giampaolo Merlini
- Amyloidosis Research and Treatment Center and Department of Molecular Medicine, Fondazione IRCCS Policlinico San Matteo and University of Pavia, Pavia, Italy.,Clinical Chemistry Laboratory, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
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8
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Pereira CD, Minamino N, Takao T. Free Thiol of Transthyretin in Human Plasma Most Accessible to Modification/Oxidation. Anal Chem 2015; 87:10785-91. [DOI: 10.1021/acs.analchem.5b03431] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
| | - Naoto Minamino
- National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565, Japan
| | - Toshifumi Takao
- Institute
for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
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9
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Baker ES, Burnum-Johnson KE, Ibrahim YM, Orton DJ, Monroe ME, Kelly RT, Moore RJ, Zhang X, Théberge R, Costello CE, Smith RD. Enhancing bottom-up and top-down proteomic measurements with ion mobility separations. Proteomics 2015; 15:2766-76. [PMID: 26046661 DOI: 10.1002/pmic.201500048] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/06/2015] [Accepted: 06/02/2015] [Indexed: 11/06/2022]
Abstract
Proteomic measurements with greater throughput, sensitivity, and structural information are essential for improving both in-depth characterization of complex mixtures and targeted studies. While LC separation coupled with MS (LC-MS) measurements have provided information on thousands of proteins in different sample types, the introduction of a separation stage that provides further component resolution and rapid structural information has many benefits in proteomic analyses. Technical advances in ion transmission and data acquisition have made ion mobility separations an opportune technology to be easily and effectively incorporated into LC-MS proteomic measurements for enhancing their information content. Herein, we report on applications illustrating increased sensitivity, throughput, and structural information by utilizing IMS-MS and LC-IMS-MS measurements for both bottom-up and top-down proteomics measurements.
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Affiliation(s)
- Erin Shammel Baker
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | | | - Yehia M Ibrahim
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Daniel J Orton
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Matthew E Monroe
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Ryan T Kelly
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Ronald J Moore
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Xing Zhang
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Roger Théberge
- Center for Biomedical Mass Spectrometry, Boston University School of Medicine, Boston, MA, USA
| | - Catherine E Costello
- Center for Biomedical Mass Spectrometry, Boston University School of Medicine, Boston, MA, USA
| | - Richard D Smith
- Biological Sciences Division, Pacific Northwest National Laboratory, Richland, WA, USA
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10
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Quantitative analysis of post-translational modifications in human serum transthyretin associated with familial amyloidotic polyneuropathy by targeted LC-MS and intact protein MS. J Proteomics 2015; 127:234-46. [PMID: 25910794 DOI: 10.1016/j.jprot.2015.04.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 04/10/2015] [Accepted: 04/13/2015] [Indexed: 11/22/2022]
Abstract
UNLABELLED Transthyretin (TTR) is an amyloidogenic tetrameric protein, present in human plasma, associated with several familial amyloidoses. Variability of TTR is not only due to point mutations in the encoding gene but also to post-translational modifications (PTMs) at Cys10, being the most common PTMs the S-sulfonation, S-glycinylcysteinylation, S-cysteinylation and S-glutathionylation. It is thought that PTMs at Cys10 may play an important biological role in the onset and pathological process of the amyloidosis. We report here the development of a methodology for quantification of PTMs in serum samples, as well as for the determination of serum TTR levels, from healthy (wt) and TTR-amyloidotic (V30M mutation) individuals. It involves an enrichment step by immunoprecipitation followed by mass spectrometry analysis of (i) the intact TTR protein and (ii) targeted LC-MS analysis of peptides carrying the PTMs of interest. Analysis of serum samples by the combination of the two methods affords complementary information on the relative and absolute amounts of the selected TTR PTM forms. It is shown that methods based on intact protein are biased for specific PTMs since they assume constant response factors, whereas the novel targeted LC-MS method provides absolute quantification of PTMs and total TTR variants. BIOLOGICAL SIGNIFICANCE The study of TTR has a high clinical relevance since it is responsible for diverse familial polyneuropathies. In particular, more than 80 point mutations have been described through genetic studies. However, genetic heterogeneity alone fails to explain the diverse onset and pathological process of the TTR related amyloidosis. The use of proteomic characterization is required to gather information about the PTMs variants present in serum, which have been suggested to be relevant for the amyloidotic pathology. This article is part of a Special Issue entitled: HUPO 2014.
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11
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Greene MJ, Klimtchuk ES, Seldin DC, Berk JL, Connors LH. Cooperative stabilization of transthyretin by clusterin and diflunisal. Biochemistry 2014; 54:268-78. [PMID: 25478940 PMCID: PMC4303310 DOI: 10.1021/bi5011249] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
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The
circulating protein transthyretin (TTR) can unfold, oligomerize,
and form highly structured amyloid fibrils that are deposited in tissues,
causing organ damage and disease. This pathogenic process is caused
by a heritable TTR point mutation in cases of familial TTR-related
amyloidosis or wild-type TTR in cases of age-associated amyloidosis
(previously called senile systemic amyloidosis). The TTR amyloid cascade
is hypothesized to begin with the dissociation of the TTR native tetrameric
structure into folded but unstable monomeric TTR subunits. Unfolding
of monomeric TTR initiates an oligomerization process leading to aggregation
and fibril formation. Numerous proteostatic mechanisms for regulating
the TTR amyloid cascade exist. Extracellular chaperones provide an
innate defense against misfolded proteins. Clusterin (CLU), a plasma
protein, has the capacity to recognize exposed hydrophobic regions
of misfolded proteins, shielding them from aggregation. We have previously
demonstrated that CLU is associated with the amyloid fibrils in cardiac
tissues from patients with TTR amyloidosis. In this study, we have
used tetrameric and monomeric TTR structural variants to determine
the ability of CLU to inhibit TTR amyloid fibril formation. Using
circular dichroism spectroscopy, we determined that CLU preferentially
stabilizes monomeric TTR and generates increasingly stable conformations
under acid stress. Moreover, studies using surface plasmon resonance
showed a direct interaction of CLU with high-molecular weight TTR
oligomers. The interactions of CLU with monomeric and aggregated TTR
proceed in a cooperative manner in the presence of diflunisal, a small
molecule drug used to stabilize TTR tetramers.
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Affiliation(s)
- Michael J Greene
- Amyloidosis Center, Boston University School of Medicine , K-507, 715 Albany Street, Boston, Massachusetts 02118, United States
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12
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Wu JW, Chen ME, Wen WS, Chen WA, Li CT, Chang CK, Lo CH, Liu HS, Wang SSS. Comparative analysis of human γD-crystallin aggregation under physiological and low pH conditions. PLoS One 2014; 9:e112309. [PMID: 25389780 PMCID: PMC4229192 DOI: 10.1371/journal.pone.0112309] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Accepted: 10/04/2014] [Indexed: 11/19/2022] Open
Abstract
Cataract, a major cause of visual impairment worldwide, is the opacification of the eye’s crystalline lens due to aggregation of the crystallin proteins. The research reported here is aimed at investigating the aggregating behavior of γ-crystallin proteins in various incubation conditions. Thioflavin T binding assay, circular dichroism spectroscopy, 1-anilinonaphthalene-8-sulfonic acid fluorescence spectroscopy, intrinsic (tryptophan) fluorescence spectroscopy, light scattering, and electron microscopy were used for structural characterization. Molecular dynamics simulations and bioinformatics prediction were performed to gain insights into the γD-crystallin mechanisms of fibrillogenesis. We first demonstrated that, except at pH 7.0 and 37°C, the aggregation of γD-crystallin was observed to be augmented upon incubation, as revealed by turbidity measurements. Next, the types of aggregates (fibrillar or non-fibrillar aggregates) formed under different incubation conditions were identified. We found that, while a variety of non-fibrillar, granular species were detected in the sample incubated under pH 7.0, the fibrillogenesis of human γD-crystallin could be induced by acidic pH (pH 2.0). In addition, circular dichroism spectroscopy, 1-anilinonaphthalene-8-sulfonic acid fluorescence spectroscopy, and intrinsic fluorescence spectroscopy were used to characterize the structural and conformational features in different incubation conditions. Our results suggested that incubation under acidic condition led to a considerable change in the secondary structure and an enhancement in solvent-exposure of the hydrophobic regions of human γD-crystallin. Finally, molecular dynamics simulations and bioinformatics prediction were performed to better explain the differences between the structures and/or conformations of the human γD-crystallin samples and to reveal potential key protein region involved in the varied aggregation behavior. Bioinformatics analyses revealed that the initiation of amyloid formation of human γD-crystallin may be associated with a region within the C-terminal domain. We believe the results from this research may contribute to a better understanding of the possible mechanisms underlying the pathogenesis of senile nuclear cataract.
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Affiliation(s)
- Josephine W. Wu
- Department of Optometry, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan
- * E-mail: (JWW); (SSW)
| | - Mei-Er Chen
- Department of Entomology, National Chung Hsing University, Taichung 402, Taiwan
| | - Wen-Sing Wen
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Wei-An Chen
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Chien-Ting Li
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Chih-Kai Chang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Chun-Hsien Lo
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Hwai-Shen Liu
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Steven S.-S. Wang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
- * E-mail: (JWW); (SSW)
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13
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Gu YJ, Ge P, Mu Y, Lu JH, Zheng F, Sun XG. Clinical and laboratory characteristics of patients having amyloidogenic transthyretin deposition in osteoarthritic knee joints. J Zhejiang Univ Sci B 2014; 15:92-9. [PMID: 24390749 DOI: 10.1631/jzus.b1300046] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVE Our aim was to investigate clinical and laboratory characteristics of osteoarthritic patients who had amyloid deposition in their knee joints. METHODS Synovial membranes were obtained from 36 patients with knee osteoarthritis (OA) who underwent joint replacement surgery. From this sample, the diagnosis of amyloid was determined by Congo red staining, which demonstrated apple-green birefringence under a polarized microscope. All synovial membranes were immunohistochemically characterized for the expressions of amyloid immunoglobulin light chain (AL-κ and AL-λ), serum amyloid-A (SAA), amyloidogenic transthyretin (ATTR), and amyloidogenic β2-microglobulin (Aβ2M). Matrix-assisted laser desorption-ionizaton/time of flight mass spectrometry (MALDI-TOF MS) was used to analyze transthyretin (TTR) isoforms in the serum of each patient. RESULTS Nine cases (25%) were found to be amyloid-positive. Immunohistochemically, eight cases (88.9%) had ATTR deposition, and one sample (11.1%) was shown to be AL-κ-positive. MALDI-TOF MS identified that the TTR in the serum of the patients was unmodified wild-type TTR, TTR-Cys-S-S-Cys, and TTR-Cys-S-S-CysGly. The age at surgery and the disease duration were significantly higher in the ATTR-positive group than in the ATTR-negative group. Knee score and function score were significantly lower in the ATTR-positive group than in the ATTR-negative group. CONCLUSIONS Amyloid deposition in synovial membranes of OA patients was found to be ATTR and AL-κ. TTR in the serum of the patients was unmodified wild-type TTR together with two isoforms. The high age at surgery, long disease duration, and a deteriorated knee function were associated with ATTR amyloid deposition in the osteoarthritic knee joints.
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Affiliation(s)
- Ya-jun Gu
- School of Medical Laboratory, Tianjin Medical University, Tianjin 300203, China; Department of Clinical Laboratory, Tianjin Medical University Cancer Institute and Hospital, Tianjin 300060, China; Department of Clinical Laboratory, Tianjin Children's Hospital, Tianjin 300074, China
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Phay M, Blinder V, Macy S, Greene MJ, Wooliver DC, Liu W, Planas A, Walsh DM, Connors LH, Primmer SR, Planque SA, Paul S, O'Nuallain B. Transthyretin Aggregate-Specific Antibodies Recognize Cryptic Epitopes on Patient-Derived Amyloid Fibrils. Rejuvenation Res 2014; 17:97-104. [DOI: 10.1089/rej.2013.1524] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Monichan Phay
- The Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Veronika Blinder
- The Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Sallie Macy
- Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee
| | - Michael J. Greene
- Amyloidosis Center, Boston University School of Medicine, Boston, Massachusetts
| | - Daniel C. Wooliver
- Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee
| | - Wen Liu
- The Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Antoni Planas
- Laboratory of Biochemistry, Institut Químic de Sarrià, Universitat Ramon Llull, Barcelona, Spain
| | - Dominic M. Walsh
- The Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Lawreen H. Connors
- Amyloidosis Center, Boston University School of Medicine, Boston, Massachusetts
| | | | - Stephanie A. Planque
- Chemical Immunology Research Center, University of Texas-Houston Medical School, Houston, Texas
| | - Sudhir Paul
- Chemical Immunology Research Center, University of Texas-Houston Medical School, Houston, Texas
| | - Brian O'Nuallain
- The Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
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Zhao L, Buxbaum JN, Reixach N. Age-related oxidative modifications of transthyretin modulate its amyloidogenicity. Biochemistry 2013; 52:1913-26. [PMID: 23414091 DOI: 10.1021/bi301313b] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The transthyretin amyloidoses are diseases of protein misfolding characterized by the extracellular deposition of fibrils and other aggregates of the homotetrameric protein transthyretin (TTR) in peripheral nerves, heart, and other tissues. Age is the major risk factor for the development of these diseases. We hypothesized that an age-associated increase in the level of protein oxidation could be involved in the onset of the senile forms of the TTR amyloidoses. To test this hypothesis, we have produced and characterized relevant age-related oxidative modifications of the wild type (WT) and the Val122Ile (V122I) TTR variant, both involved in cardiac TTR deposition in the elderly. Our studies show that methionine/cysteine-oxidized TTR and carbonylated TTR from either the WT or the V122I variant are thermodynamically less stable than their nonoxidized counterparts. Moreover, carbonylated WT and carbonylated V122I TTR have a stronger propensity to form aggregates and fibrils than WT and V122I TTR, respectively, at physiologically attainable pH values. It is well-known that TTR tetramer dissociation, the limiting step for aggregation and amyloid fibril formation, can be prevented by small molecules that bind the TTR tetramer interface. Here, we report that carbonylated WT TTR is less amenable to resveratrol-mediated tetramer stabilization than WT TTR. All the oxidized forms of TTR tested are cytotoxic to a human cardiomyocyte cell line known to be a target for cardiac-specific TTR variants. Overall, these studies demonstrate that age-related oxidative modifications of TTR can contribute to the onset of the senile forms of the TTR amyloidoses.
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Affiliation(s)
- Lei Zhao
- Department of Molecular and Experimental Medicine, The Scripps Research Institute , 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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16
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Transthyretin blocks retinol uptake and cell signaling by the holo-retinol-binding protein receptor STRA6. Mol Cell Biol 2012; 32:3851-9. [PMID: 22826435 DOI: 10.1128/mcb.00775-12] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Vitamin A is secreted from cellular stores and circulates in blood bound to retinol-binding protein (RBP). In turn, holo-RBP associates in plasma with transthyretin (TTR) to form a ternary RBP-retinol-TTR complex. It is believed that binding to TTR prevents the loss of RBP by filtration in the kidney. At target cells, holo-RBP is recognized by STRA6, a plasma membrane protein that serves a dual role: it mediates uptake of retinol from extracellular RBP into cells, and it functions as a cytokine receptor that, upon binding holo-RBP, triggers a JAK/STAT signaling cascade. We previously showed that STRA6-mediated signaling underlies the ability of RBP to induce insulin resistance. However, the role that TTR, the binding partner of holo-RBP in blood, plays in STRA6-mediated activities remained unknown. Here we show that TTR blocks the ability of holo-RBP to associate with STRA6 and thereby effectively suppresses both STRA6-mediated retinol uptake and STRA6-initiated cell signaling. Consequently, TTR protects mice from RBP-induced insulin resistance, reflected by reduced phosphorylation of insulin receptor and glucose tolerance tests. The data indicate that STRA6 functions only under circumstances where the plasma RBP level exceeds that of TTR and demonstrate that, in addition to preventing the loss of RBP, TTR plays a central role in regulating holo-RBP/STRA6 signaling.
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Kingsbury JS, Laue TM, Chase SF, Connors LH. Detection of high-molecular-weight amyloid serum protein complexes using biological on-line tracer sedimentation. Anal Biochem 2012; 425:151-6. [PMID: 22465331 PMCID: PMC3354566 DOI: 10.1016/j.ab.2012.03.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 03/19/2012] [Accepted: 03/20/2012] [Indexed: 01/14/2023]
Abstract
The systemic amyloidoses are a rare but deadly class of protein folding disorders with significant unmet diagnostic and therapeutic needs. The current model for symptomatic amyloid progression includes a causative role for soluble toxic aggregates as well as for the fibrillar tissue deposits. Although much research is focused on elucidating the potential mechanism of aggregate toxicity, evidence to support their existence in vivo has been limited. We report the use of a technique we have termed biological on-line tracer sedimentation (BOLTS) to detect abnormal high-molecular-weight complexes (HMWCs) in serum samples from individuals with systemic amyloidosis due to aggregation and deposition of wild-type transthyretin (senile systemic amyloidosis, SSA) or monoclonal immunoglobulin light chain (AL amyloidosis). In this proof-of-concept study, HMWCs were observed in 31 of 77 amyloid samples (40.3%). HMWCs were not detected in any of the 17 nonamyloid control samples subjected to BOLTS analyses. These findings support the existence of potentially toxic amyloid aggregates and suggest that BOLTS may be a useful analytic and diagnostic platform in the study of the amyloidoses or other diseases where abnormal molecular complexes are formed in serum.
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Affiliation(s)
- Jonathan S. Kingsbury
- Alan and Sandra Gerry Amyloid Research Laboratory in the Amyloid Treatment and Research Program, Boston University School of Medicine, Boston, Massachusetts 02118, USA
| | - Thomas M. Laue
- Department of Biochemistry and Molecular Biology, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - Susan F. Chase
- Department of Biochemistry and Molecular Biology, University of New Hampshire, Durham, New Hampshire 03824, USA
| | - Lawreen H. Connors
- Alan and Sandra Gerry Amyloid Research Laboratory in the Amyloid Treatment and Research Program, Boston University School of Medicine, Boston, Massachusetts 02118, USA
- Department of Biochemistry and Molecular Biology, University of New Hampshire, Durham, New Hampshire 03824, USA
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CM156, a sigma receptor ligand, reverses cocaine-induced place conditioning and transcriptional responses in the brain. Pharmacol Biochem Behav 2011; 101:174-80. [PMID: 22234290 DOI: 10.1016/j.pbb.2011.12.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Revised: 12/12/2011] [Accepted: 12/22/2011] [Indexed: 01/25/2023]
Abstract
Repeated exposure to cocaine induces neuroadaptations which contribute to the rewarding properties of cocaine. Using cocaine-induced conditioned place preference (CPP) as an animal model of reward, earlier studies have shown that sigma (σ) receptor ligands can attenuate the acquisition, expression and reactivation of CPP. However, the underlying molecular mechanisms that are associated with these changes are not yet understood. In the present study, CM156, a novel antagonist with high selectivity and affinity for σ receptors was used to attenuate the expression of cocaine-induced CPP in mice. Immediately following the behavioral evaluations, mouse brain tissues were collected and alterations in gene expression in half brain samples were profiled by cDNA microarray analysis. Microarray data was analyzed by three distinct normalization methods and four genes were consistently found to be upregulated by cocaine when compared to saline controls. Each of these gene changes were found by more than one normalization method to be reversed by at least one dose of CM156. Quantitative real time PCR confirmed that a single administration of CM156 was able to reverse the cocaine-induced increases in three of these four genes: metastasis associated lung adenocarcinoma transcript 1 (malat1), tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein (ywhaz), and transthyretin (ttr). These genes are involved in processes related to neuroplasticity and RNA editing. The data presented herein provides evidence that pharmacological intervention with a putative σ receptor antagonist reverses alterations in gene expression that are associated with cocaine-induced reward.
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Wen WS, Hsieh MC, Wang SSS. High-level expression and purification of human γD-crystallin in Escherichia coli. J Taiwan Inst Chem Eng 2011. [DOI: 10.1016/j.jtice.2010.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Liu L, Hou J, Du J, Chumanov RS, Xu Q, Ge Y, Johnson JA, Murphy RM. Differential modification of Cys10 alters transthyretin's effect on beta-amyloid aggregation and toxicity. Protein Eng Des Sel 2009; 22:479-88. [PMID: 19549717 PMCID: PMC2719498 DOI: 10.1093/protein/gzp025] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2009] [Revised: 05/20/2009] [Accepted: 05/23/2009] [Indexed: 12/21/2022] Open
Abstract
Tg2576 mice produce high levels of beta-amyloid (Abeta) and develop amyloid deposits, but lack neurofibrillary tangles and do not suffer the extensive neuronal cell loss characteristic of Alzheimer's disease. Protection from Abeta toxicity has been attributed to up-regulation of transthyretin (TTR), a normal component of plasma and cerebrospinal fluid. We compared the effect of TTR purified from human plasma (pTTR) with that produced recombinantly (rTTR) on Abeta aggregation and toxicity. pTTR slowed Abeta aggregation but failed to protect primary cortical neurons from Abeta toxicity. In contrast, rTTR accelerated aggregation, while effectively protecting neurons. This inverse correlation between Abeta aggregation kinetics and toxicity is consistent with the hypothesis that soluble intermediates rather than insoluble fibrils are the most toxic Abeta species. We carried out a detailed comparison of pTTR with rTTR to ascertain the probable cause of these different effects. No differences in secondary, tertiary or quaternary structure were detected. However, pTTR differed from rTTR in the extent and nature of modification at Cys10. We hypothesize that differential modification at Cys10 regulates TTR's effect on Abeta aggregation and toxicity.
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Affiliation(s)
- Lin Liu
- Department of Chemical and Biological Engineering, University of Wisconsin, 1415 Engineering Drive, Madison, WI 53706
| | - Jie Hou
- Department of Chemical and Biological Engineering, University of Wisconsin, 1415 Engineering Drive, Madison, WI 53706
| | - Jiali Du
- Department of Chemical and Biological Engineering, University of Wisconsin, 1415 Engineering Drive, Madison, WI 53706
| | - Robert S. Chumanov
- Cellular and Molecular Biology Program and McArdle Laboratory for Cancer Research, University of Wisconsin, 1400 University Ave., Madison, WI 53706
| | - Qingge Xu
- Human Proteomics Program, School of Medicine and Public Health, University of Wisconsin, 1300 University Ave., Madison, WI 53706
| | - Ying Ge
- Human Proteomics Program, School of Medicine and Public Health, University of Wisconsin, 1300 University Ave., Madison, WI 53706
| | - Jeffrey A. Johnson
- Cellular and Molecular Biology Program and McArdle Laboratory for Cancer Research, University of Wisconsin, 1400 University Ave., Madison, WI 53706
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin, 777 Highland Ave., Madison, WI 53705, USA
| | - Regina M. Murphy
- Department of Chemical and Biological Engineering, University of Wisconsin, 1415 Engineering Drive, Madison, WI 53706
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Kingsbury JS, Laue TM, Klimtchuk ES, Théberge R, Costello CE, Connors LH. The modulation of transthyretin tetramer stability by cysteine 10 adducts and the drug diflunisal. Direct analysis by fluorescence-detected analytical ultracentrifugation. J Biol Chem 2008; 283:11887-96. [PMID: 18326041 DOI: 10.1074/jbc.m709638200] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Transthyretin (TTR) is normally a stable plasma protein. However, in cases of familial TTR-related amyloidosis and senile systemic amyloidosis (SSA), TTR is deposited as amyloid fibrils, leading to organ dysfunction and possibly death. The mechanism by which TTR undergoes the transition from stable, soluble precursor to insoluble amyloid fibril and the factors that promote this process are largely undetermined. Most models involve the dissociation of the native TTR tetramer as the initial step. It is largely accepted that the TTR gene mutations associated with TTR-related amyloidosis lead to the expression of variant proteins that are intrinsically unstable and prone to aggregation. It has been suggested that amyloidogenicity may be conferred to wild-type TTR (the form deposited in SSA) by chemical modification of the lone cysteine residue (Cys(10)) through mixed disulfide bonds. S-Sulfonation and S-cysteinylation are prevalent TTR modifications physiologically, and studies have suggested their ability to modulate the structure of TTR under denaturing conditions. In the present study, we have used fluorescence-detected sedimentation velocity to determine the effect of S-sulfonate and S-cysteine on the quaternary structural stability of fluorophore-conjugated recombinant TTR under nondenaturing conditions. We determined that S-sulfonation stabilized TTR tetramer stability by a factor of 7, whereas S-cysteinylation enhanced dissociation by 2-fold with respect to the unmodified form. In addition, we report the direct observation of tetramer stabilization by the potential therapeutic compound diflunisal. Finally, as proof of concept, we report the sedimentation of TTR in serum and the qualitative assessment of the resulting data.
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Affiliation(s)
- Jonathan S Kingsbury
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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