1
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Hansen KH, Byeon CH, Liu Q, Drace T, Boesen T, Conway JF, Andreasen M, Akbey Ü. Structure of biofilm-forming functional amyloid PSMα1 from Staphylococcus aureus. Proc Natl Acad Sci U S A 2024; 121:e2406775121. [PMID: 39116134 PMCID: PMC11331129 DOI: 10.1073/pnas.2406775121] [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: 04/03/2024] [Accepted: 06/25/2024] [Indexed: 08/10/2024] Open
Abstract
Biofilm-protected pathogenic Staphylococcus aureus causes chronic infections that are difficult to treat. An essential building block of these biofilms are functional amyloid fibrils that assemble from phenol-soluble modulins (PSMs). PSMα1 cross-seeds other PSMs into cross-β amyloid folds and is therefore a key element in initiating biofilm formation. However, the paucity of high-resolution structures hinders efforts to prevent amyloid assembly and biofilm formation. Here, we present a 3.5 Å resolution density map of the major PSMα1 fibril form revealing a left-handed cross-β fibril composed of two C2-symmetric U-shaped protofilaments whose subunits are unusually tilted out-of-plane. Monomeric α-helical PSMα1 is extremely cytotoxic to cells, despite the moderate toxicity of the cross-β fibril. We suggest mechanistic insights into the PSM functional amyloid formation and conformation transformation on the path from monomer-to-fibril formation. Details of PSMα1 assembly and fibril polymorphism suggest how S. aureus utilizes functional amyloids to form biofilms and establish a framework for developing therapeutics against infection and antimicrobial resistance.
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Affiliation(s)
- Kasper Holst Hansen
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA15261
- Department of Biomedicine, Aarhus University, Aarhus8000, Denmark
| | - Chang Hyeock Byeon
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA15261
| | - Qian Liu
- Department of Biomedicine, Aarhus University, Aarhus8000, Denmark
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus8000, Denmark
| | - Taner Drace
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus8000, Denmark
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus8000, Denmark
| | - Thomas Boesen
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus8000, Denmark
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus8000, Denmark
| | - James F. Conway
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA15261
| | - Maria Andreasen
- Department of Biomedicine, Aarhus University, Aarhus8000, Denmark
| | - Ümit Akbey
- Department of Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA15261
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2
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Cereghetti G, Kissling VM, Koch LM, Arm A, Schmidt CC, Thüringer Y, Zamboni N, Afanasyev P, Linsenmeier M, Eichmann C, Kroschwald S, Zhou J, Cao Y, Pfizenmaier DM, Wiegand T, Cadalbert R, Gupta G, Boehringer D, Knowles TPJ, Mezzenga R, Arosio P, Riek R, Peter M. An evolutionarily conserved mechanism controls reversible amyloids of pyruvate kinase via pH-sensing regions. Dev Cell 2024; 59:1876-1891.e7. [PMID: 38788715 DOI: 10.1016/j.devcel.2024.04.018] [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: 06/01/2022] [Revised: 10/15/2023] [Accepted: 04/26/2024] [Indexed: 05/26/2024]
Abstract
Amyloids are known as irreversible aggregates associated with neurodegenerative diseases. However, recent evidence shows that a subset of amyloids can form reversibly and fulfill essential cellular functions. Yet, the molecular mechanisms regulating functional amyloids and distinguishing them from pathological aggregates remain unclear. Here, we investigate the conserved principles of amyloid reversibility by studying the essential metabolic enzyme pyruvate kinase (PK) in yeast and human cells. We demonstrate that yeast PK (Cdc19) and human PK (PKM2) form reversible amyloids through a pH-sensitive amyloid core. Stress-induced cytosolic acidification promotes aggregation via protonation of specific glutamate (yeast) or histidine (human) residues within the amyloid core. Mutations mimicking protonation cause constitutive PK aggregation, while non-protonatable PK mutants remain soluble even upon stress. Physiological PK aggregation is coupled to metabolic rewiring and glycolysis arrest, causing severe growth defects when misregulated. Our work thus identifies an evolutionarily conserved, potentially widespread mechanism regulating functional amyloids during stress.
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Affiliation(s)
- Gea Cereghetti
- Institute of Biochemistry, Department of Biology, ETH Zürich, 8093 Zürich, Switzerland; Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, UK.
| | - Vera M Kissling
- Institute of Biochemistry, Department of Biology, ETH Zürich, 8093 Zürich, Switzerland; Particles-Biology Interactions Laboratory, Department of Materials Meet Life, Empa, 9014 St. Gallen, Switzerland
| | - Lisa M Koch
- Institute of Biochemistry, Department of Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - Alexandra Arm
- Institute of Biochemistry, Department of Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - Claudia C Schmidt
- Institute of Biochemistry, Department of Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - Yannik Thüringer
- Institute of Biochemistry, Department of Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - Nicola Zamboni
- Institute of Molecular Systems Biology, Department of Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - Pavel Afanasyev
- Cryo-EM Knowledge Hub (CEMK), ETH Zurich, 8093 Zürich, Switzerland
| | - Miriam Linsenmeier
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland
| | - Cédric Eichmann
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland
| | - Sonja Kroschwald
- Institute of Biochemistry, Department of Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - Jiangtao Zhou
- Department of Health Sciences & Technology, ETH Zürich, 8092 Zürich, Switzerland
| | - Yiping Cao
- Department of Health Sciences & Technology, ETH Zürich, 8092 Zürich, Switzerland
| | - Dorota M Pfizenmaier
- Institute of Biochemistry, Department of Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - Thomas Wiegand
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland; Max Planck Institute for Chemical Energy Conversion, 45470 Mülheim an der Ruhr, Germany; Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, 52074 Aachen, Germany
| | - Riccardo Cadalbert
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland
| | - Govind Gupta
- Particles-Biology Interactions Laboratory, Department of Materials Meet Life, Empa, 9014 St. Gallen, Switzerland
| | | | - Tuomas P J Knowles
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, UK
| | - Raffaele Mezzenga
- Department of Health Sciences & Technology, ETH Zürich, 8092 Zürich, Switzerland
| | - Paolo Arosio
- Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland
| | - Roland Riek
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, 8093 Zürich, Switzerland
| | - Matthias Peter
- Institute of Biochemistry, Department of Biology, ETH Zürich, 8093 Zürich, Switzerland.
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3
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Harel I, Chen YR, Ziv I, Singh PP, Heinzer D, Navarro Negredo P, Goshtchevsky U, Wang W, Astre G, Moses E, McKay A, Machado BE, Hebestreit K, Yin S, Sánchez Alvarado A, Jarosz DF, Brunet A. Identification of protein aggregates in the aging vertebrate brain with prion-like and phase-separation properties. Cell Rep 2024; 43:112787. [PMID: 38810650 PMCID: PMC11285089 DOI: 10.1016/j.celrep.2023.112787] [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: 03/21/2022] [Revised: 04/23/2023] [Accepted: 06/26/2023] [Indexed: 05/31/2024] Open
Abstract
Protein aggregation, which can sometimes spread in a prion-like manner, is a hallmark of neurodegenerative diseases. However, whether prion-like aggregates form during normal brain aging remains unknown. Here, we use quantitative proteomics in the African turquoise killifish to identify protein aggregates that accumulate in old vertebrate brains. These aggregates are enriched for prion-like RNA-binding proteins, notably the ATP-dependent RNA helicase DDX5. We validate that DDX5 forms aggregate-like puncta in the brains of old killifish and mice. Interestingly, DDX5's prion-like domain allows these aggregates to propagate across many generations in yeast. In vitro, DDX5 phase separates into condensates. Mutations that abolish DDX5 prion propagation also impair the protein's ability to phase separate. DDX5 condensates exhibit enhanced enzymatic activity, but they can mature into inactive, solid aggregates. Our findings suggest that protein aggregates with prion-like properties form during normal brain aging, which could have implications for the age-dependency of cognitive decline.
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Affiliation(s)
- Itamar Harel
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; The Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel.
| | - Yiwen R Chen
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA 94305, USA
| | - Inbal Ziv
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA 94305, USA
| | - Param Priya Singh
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Daniel Heinzer
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | | | - Uri Goshtchevsky
- The Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Wei Wang
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Gwendoline Astre
- The Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Eitan Moses
- The Silberman Institute, the Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel
| | - Andrew McKay
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Ben E Machado
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Katja Hebestreit
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Sifei Yin
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA 94305, USA
| | | | - Daniel F Jarosz
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University, Stanford, CA 94305, USA.
| | - Anne Brunet
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; Glenn Laboratories for the Biology of Aging, Stanford University, Stanford, CA 94305, USA.
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4
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Zhou J, Assenza S, Tatli M, Tian J, Ilie IM, Starostin EL, Caflisch A, Knowles TPJ, Dietler G, Ruggeri FS, Stahlberg H, Sekatskii SK, Mezzenga R. Hierarchical Protofilament Intertwining Rules the Formation of Mixed-Curvature Amyloid Polymorphs. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2402740. [PMID: 38899849 DOI: 10.1002/advs.202402740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 05/19/2024] [Indexed: 06/21/2024]
Abstract
Amyloid polymorphism is a hallmark of almost all amyloid species, yet the mechanisms underlying the formation of amyloid polymorphs and their complex architectures remain elusive. Commonly, two main mesoscopic topologies are found in amyloid polymorphs characterized by non-zero Gaussian and mean curvatures: twisted ribbons and helical fibrils, respectively. Here, a rich heterogeneity of configurations is demonstrated on insulin amyloid fibrils, where protofilament packing can occur, besides the common polymorphs, also in a combined mode forming mixed-curvature polymorphs. Through AFM statistical analysis, an extended array of heterogeneous architectures that are rationalized by mesoscopic theoretical arguments are identified. Notably, an unusual fibrillization pathway is also unraveled toward mixed-curvature polymorphs via the widespread recruitment and intertwining of protofilaments and protofibrils. The results present an original view of amyloid polymorphism and advance the fundamental understanding of the fibrillization mechanism from single protofilaments into mature amyloid fibrils.
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Affiliation(s)
- Jiangtao Zhou
- Laboratory of Physics of Living Matter, Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, CH-1015, Switzerland
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Salvatore Assenza
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, Madrid, 28049, Spain
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, Madrid, 28049, Spain
- Instituto Nicolás Cabrera, Universidad Autónoma de Madrid, Madrid, 28049, Spain
| | - Meltem Tatli
- Laboratory of Biological Electron Microscopy, Institute of Physics, SB, EPFL, and Dep. of Fund. Microbiol., Faculty of Biology and Medicine, UNIL, Rt. de la Sorge, Lausanne, 1015, Switzerland
| | - Jiawen Tian
- Laboratory of Biological Electron Microscopy, Institute of Physics, SB, EPFL, and Dep. of Fund. Microbiol., Faculty of Biology and Medicine, UNIL, Rt. de la Sorge, Lausanne, 1015, Switzerland
| | - Ioana M Ilie
- van't Hoff Institute for Molecular Sciences, University of Amsterdam, P.O. Box 94157, Amsterdam, 1090 GD, The Netherlands
- Amsterdam Center for Multiscale Modeling (ACMM), University of Amsterdam, P.O. Box 94157, Amsterdam, 1090 GD, The Netherlands
| | - Eugene L Starostin
- Department of Civil, Environmental & Geomatic Engineering, University College London, Gower Street, London, WC1E 6BT, UK
| | - Amedeo Caflisch
- Department of Biochemistry, University of Zürich, Zürich, CH-8057, Switzerland
| | - Tuomas P J Knowles
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Giovanni Dietler
- Laboratory of Physics of Living Matter, Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, CH-1015, Switzerland
| | - Francesco S Ruggeri
- Laboratory of Organic Chemistry, Wageningen University & Research, Stippeneng 4, Wageningen, 6703 WE, The Netherlands
- Physical Chemistry and Soft Matter, Wageningen University & Research, Stippeneng 4, Wageningen, 6703 WE, The Netherlands
| | - Henning Stahlberg
- Laboratory of Biological Electron Microscopy, Institute of Physics, SB, EPFL, and Dep. of Fund. Microbiol., Faculty of Biology and Medicine, UNIL, Rt. de la Sorge, Lausanne, 1015, Switzerland
| | - Sergey K Sekatskii
- Laboratory of Physics of Living Matter, Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, CH-1015, Switzerland
- Laboratory of Biological Electron Microscopy, Institute of Physics, SB, EPFL, and Dep. of Fund. Microbiol., Faculty of Biology and Medicine, UNIL, Rt. de la Sorge, Lausanne, 1015, Switzerland
| | - Raffaele Mezzenga
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
- Department of Materials, ETH Zurich, Zurich, 8093, Switzerland
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5
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Stewart RK, Nguyen P, Laederach A, Volkan PC, Sawyer JK, Fox DT. Orb2 enables rare-codon-enriched mRNA expression during Drosophila neuron differentiation. Nat Commun 2024; 15:5270. [PMID: 38902233 PMCID: PMC11190236 DOI: 10.1038/s41467-024-48344-8] [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: 08/10/2023] [Accepted: 04/25/2024] [Indexed: 06/22/2024] Open
Abstract
Regulation of codon optimality is an increasingly appreciated layer of cell- and tissue-specific protein expression control. Here, we use codon-modified reporters to show that differentiation of Drosophila neural stem cells into neurons enables protein expression from rare-codon-enriched genes. From a candidate screen, we identify the cytoplasmic polyadenylation element binding (CPEB) protein Orb2 as a positive regulator of rare-codon-dependent mRNA stability in neurons. Using RNA sequencing, we reveal that Orb2-upregulated mRNAs in the brain with abundant Orb2 binding sites have a rare-codon bias. From these Orb2-regulated mRNAs, we demonstrate that rare-codon enrichment is important for mRNA stability and social behavior function of the metabotropic glutamate receptor (mGluR). Our findings reveal a molecular mechanism by which neural stem cell differentiation shifts genetic code regulation to enable critical mRNA stability and protein expression.
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Affiliation(s)
- Rebeccah K Stewart
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC, USA
- Duke Regeneration Center, Duke University, Durham, NC, USA
| | - Patrick Nguyen
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC, USA
| | - Alain Laederach
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
| | | | - Jessica K Sawyer
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC, USA
- Duke Regeneration Center, Duke University, Durham, NC, USA
| | - Donald T Fox
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC, USA.
- Duke Regeneration Center, Duke University, Durham, NC, USA.
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6
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Joyce M, Falconio FA, Blackhurst L, Prieto-Godino L, French AS, Gilestro GF. Divergent evolution of sleep in Drosophila species. Nat Commun 2024; 15:5091. [PMID: 38876988 PMCID: PMC11178934 DOI: 10.1038/s41467-024-49501-9] [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] [Received: 07/28/2023] [Accepted: 06/05/2024] [Indexed: 06/16/2024] Open
Abstract
Living organisms synchronize their biological activities with the earth's rotation through the circadian clock, a molecular mechanism that regulates biology and behavior daily. This synchronization factually maximizes positive activities (e.g., social interactions, feeding) during safe periods, and minimizes exposure to dangers (e.g., predation, darkness) typically at night. Beyond basic circadian regulation, some behaviors like sleep have an additional layer of homeostatic control, ensuring those essential activities are fulfilled. While sleep is predominantly governed by the circadian clock, a secondary homeostatic regulator, though not well-understood, ensures adherence to necessary sleep amounts and hints at a fundamental biological function of sleep beyond simple energy conservation and safety. Here we explore sleep regulation across seven Drosophila species with diverse ecological niches, revealing that while circadian-driven sleep aspects are consistent, homeostatic regulation varies significantly. The findings suggest that in Drosophilids, sleep evolved primarily for circadian purposes. The more complex, homeostatically regulated functions of sleep appear to have evolved independently in a species-specific manner, and are not universally conserved. This laboratory model may reproduce and recapitulate primordial sleep evolution.
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Affiliation(s)
- Michaela Joyce
- Department of Life Sciences, Imperial College London, London, UK
- The Francis Crick Research Institute, London, UK
| | | | | | | | - Alice S French
- Department of Life Sciences, Imperial College London, London, UK.
- The Francis Crick Research Institute, London, UK.
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK.
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7
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Bokros M, Balukoff NC, Grunfeld A, Sebastiao M, Beurel E, Bourgault S, Lee S. RNA tailing machinery drives amyloidogenic phase transition. Proc Natl Acad Sci U S A 2024; 121:e2316734121. [PMID: 38805292 PMCID: PMC11161805 DOI: 10.1073/pnas.2316734121] [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: 09/26/2023] [Accepted: 04/18/2024] [Indexed: 05/30/2024] Open
Abstract
The RNA tailing machinery adds nucleotides to the 3'-end of RNA molecules that are implicated in various biochemical functions, including protein synthesis and RNA stability. Here, we report a role for the RNA tailing machinery as enzymatic modifiers of intracellular amyloidogenesis. A targeted RNA interference screen identified Terminal Nucleotidyl-transferase 4b (TENT4b/Papd5) as an essential participant in the amyloidogenic phase transition of nucleoli into solid-like Amyloid bodies. Full-length-and-mRNA sequencing uncovered starRNA, a class of unusually long untemplated RNA molecules synthesized by TENT4b. StarRNA consists of short rRNA fragments linked to long, linear mixed tails that operate as polyanionic stimulators of amyloidogenesis in cells and in vitro. Ribosomal intergenic spacer noncoding RNA (rIGSRNA) recruit TENT4b in intranucleolar foci to coordinate starRNA synthesis driving their amyloidogenic phase transition. The exoribonuclease RNA Exosome degrades starRNA and functions as a general suppressor of cellular amyloidogenesis. We propose that amyloidogenic phase transition is under tight enzymatic control by the RNA tailing and exosome axis.
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Affiliation(s)
- Michael Bokros
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL33136
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, Cancer Epigenetics Program, University of Miami, Miami, FL33136
| | - Nathan C. Balukoff
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL33136
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, Cancer Epigenetics Program, University of Miami, Miami, FL33136
| | - Alex Grunfeld
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL33136
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, Cancer Epigenetics Program, University of Miami, Miami, FL33136
| | - Mathew Sebastiao
- Department of Chemistry, Université du Québec à Montréal, MontrealQCH3C 3P8, Canada
- Quebec Network for Research on Protein Function, Engineering, and Applications, PROTEO, Montreal, QCH3C 3P8, Canada
| | - Eléonore Beurel
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL33136
- Department of Psychiatry and Behavioral Sciences, Miller School of Medicine, University of Miami, Miami, FL33136
| | - Steve Bourgault
- Department of Chemistry, Université du Québec à Montréal, MontrealQCH3C 3P8, Canada
- Quebec Network for Research on Protein Function, Engineering, and Applications, PROTEO, Montreal, QCH3C 3P8, Canada
| | - Stephen Lee
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL33136
- Sylvester Comprehensive Cancer Center, Miller School of Medicine, Cancer Epigenetics Program, University of Miami, Miami, FL33136
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8
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Mo X, Zhang Z, Song J, Wang Y, Yu Z. Self-assembly of peptides in living cells for disease theranostics. J Mater Chem B 2024; 12:4289-4306. [PMID: 38595070 DOI: 10.1039/d4tb00365a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
The past few decades have witnessed substantial progress in biomedical materials for addressing health concerns and improving disease therapeutic and diagnostic efficacy. Conventional biomedical materials are typically created through an ex vivo approach and are usually utilized under physiological environments via transfer from preparative media. This transfer potentially gives rise to challenges for the efficient preservation of the bioactivity and implementation of theranostic goals on site. To overcome these issues, the in situ synthesis of biomedical materials on site has attracted great attention in the past few years. Peptides, which exhibit remarkable biocompability and reliable noncovalent interactions, can be tailored via tunable assembly to precisely create biomedical materials. In this review, we summarize the progress in the self-assembly of peptides in living cells for disease diagnosis and therapy. After a brief introduction to the basic design principles of peptide assembly systems in living cells, the applications of peptide assemblies for bioimaging and disease treatment are highlighted. The challenges in the field of peptide self-assembly in living cells and the prospects for novel peptide assembly systems towards next-generation biomaterials are also discussed, which will hopefully help elucidate the great potential of peptide assembly in living cells for future healthcare applications.
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Affiliation(s)
- Xiaowei Mo
- Key Laboratory of Functional Polymer Materials, Ministry of Education, State Key Laboratory of Medicinal Chemical Biology, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, China.
| | - Zeyu Zhang
- Key Laboratory of Functional Polymer Materials, Ministry of Education, State Key Laboratory of Medicinal Chemical Biology, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, China.
| | - Jinyan Song
- Key Laboratory of Functional Polymer Materials, Ministry of Education, State Key Laboratory of Medicinal Chemical Biology, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, China.
| | - Yushi Wang
- Key Laboratory of Functional Polymer Materials, Ministry of Education, State Key Laboratory of Medicinal Chemical Biology, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, China.
| | - Zhilin Yu
- Key Laboratory of Functional Polymer Materials, Ministry of Education, State Key Laboratory of Medicinal Chemical Biology, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, China.
- Haihe Laboratory of Synthetic Biology, 21 West 15th Avenue, Tianjin 300308, China
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9
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van der Wel PC. Solid-state nuclear magnetic resonance in the structural study of polyglutamine aggregation. Biochem Soc Trans 2024; 52:719-731. [PMID: 38563485 PMCID: PMC11088915 DOI: 10.1042/bst20230731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 03/06/2024] [Accepted: 03/19/2024] [Indexed: 04/04/2024]
Abstract
The aggregation of proteins into amyloid-like fibrils is seen in many neurodegenerative diseases. Recent years have seen much progress in our understanding of these misfolded protein inclusions, thanks to advances in techniques such as solid-state nuclear magnetic resonance (ssNMR) spectroscopy and cryogenic electron microscopy (cryo-EM). However, multiple repeat-expansion-related disorders have presented special challenges to structural elucidation. This review discusses the special role of ssNMR analysis in the study of protein aggregates associated with CAG repeat expansion disorders. In these diseases, the misfolding and aggregation affect mutant proteins with expanded polyglutamine segments. The most common disorder, Huntington's disease (HD), is connected to the mutation of the huntingtin protein. Since the discovery of the genetic causes for HD in the 1990s, steady progress in our understanding of the role of protein aggregation has depended on the integrative and interdisciplinary use of multiple types of structural techniques. The heterogeneous and dynamic features of polyQ protein fibrils, and in particular those formed by huntingtin N-terminal fragments, have made these aggregates into challenging targets for structural analysis. ssNMR has offered unique insights into many aspects of these amyloid-like aggregates. These include the atomic-level structure of the polyglutamine core, but also measurements of dynamics and solvent accessibility of the non-core flanking domains of these fibrils' fuzzy coats. The obtained structural insights shed new light on pathogenic mechanisms behind this and other protein misfolding diseases.
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10
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Chitty C, Kuliga K, Xue WF. Atomic force microscopy 3D structural reconstruction of individual particles in the study of amyloid protein assemblies. Biochem Soc Trans 2024; 52:761-771. [PMID: 38600027 DOI: 10.1042/bst20230857] [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: 12/19/2023] [Revised: 03/11/2024] [Accepted: 04/02/2024] [Indexed: 04/12/2024]
Abstract
Recent developments in atomic force microscopy (AFM) image analysis have made three-dimensional (3D) structural reconstruction of individual particles observed on 2D AFM height images a reality. Here, we review the emerging contact point reconstruction AFM (CPR-AFM) methodology and its application in 3D reconstruction of individual helical amyloid filaments in the context of the challenges presented by the structural analysis of highly polymorphous and heterogeneous amyloid protein structures. How individual particle-level structural analysis can contribute to resolving the amyloid polymorph structure-function relationships, the environmental triggers leading to protein misfolding and aggregation into amyloid species, the influences by the conditions or minor fluctuations in the initial monomeric protein structure on the speed of amyloid fibril formation, and the extent of the different types of amyloid species that can be formed, are discussed. Future perspectives in the capabilities of AFM-based 3D structural reconstruction methodology exploiting synergies with other recent AFM technology advances are also discussed to highlight the potential of AFM as an emergent general, accessible and multimodal structural biology tool for the analysis of individual biomolecules.
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Affiliation(s)
- Claudia Chitty
- Division of Natural Sciences, School of Biosciences, University of Kent, CT2 7NJ Canterbury, U.K
| | - Kinga Kuliga
- Division of Natural Sciences, School of Biosciences, University of Kent, CT2 7NJ Canterbury, U.K
| | - Wei-Feng Xue
- Division of Natural Sciences, School of Biosciences, University of Kent, CT2 7NJ Canterbury, U.K
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11
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Agha MM, Uversky VN. Morphological features and types of aggregated structures. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2024; 206:85-109. [PMID: 38811090 DOI: 10.1016/bs.pmbts.2024.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
In vivo, protein aggregation arises due to incorrect folding or misfolding. The aggregation of proteins into amyloid fibrils is the characteristic feature of various misfolding diseases known as amyloidosis, such as Alzheimer's and Parkinson's disease. The heterogeneous nature of these fibrils restricts the extent to which their structure may be characterized. Advancements in techniques, such as X-ray diffraction, cryo-electron microscopy, and solid-state NMR have yielded intricate insights into structures of different amyloid fibrils. These studies have unveiled a diverse range of polymorphic structures that typically conform to the cross-β amyloid pattern. This chapter provides a concise overview of the information acquired in the field of protein aggregation, with particular focus on amyloids.
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Affiliation(s)
- Mansoureh Mirza Agha
- Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Vladimir N Uversky
- Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences, Institute for Biological Instrumentation, Pushchino, Russia; Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, United States.
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12
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Desai M, Hemant, Deo A, Naik J, Dhamale P, Kshirsagar A, Bose T, Majumdar A. Mrj is a chaperone of the Hsp40 family that regulates Orb2 oligomerization and long-term memory in Drosophila. PLoS Biol 2024; 22:e3002585. [PMID: 38648719 PMCID: PMC11034981 DOI: 10.1371/journal.pbio.3002585] [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] [Received: 03/27/2023] [Accepted: 03/12/2024] [Indexed: 04/25/2024] Open
Abstract
Orb2 the Drosophila homolog of cytoplasmic polyadenylation element binding (CPEB) protein forms prion-like oligomers. These oligomers consist of Orb2A and Orb2B isoforms and their formation is dependent on the oligomerization of the Orb2A isoform. Drosophila with a mutation diminishing Orb2A's prion-like oligomerization forms long-term memory but fails to maintain it over time. Since this prion-like oligomerization of Orb2A plays a crucial role in the maintenance of memory, here, we aim to find what regulates this oligomerization. In an immunoprecipitation-based screen, we identify interactors of Orb2A in the Hsp40 and Hsp70 families of proteins. Among these, we find an Hsp40 family protein Mrj as a regulator of the conversion of Orb2A to its prion-like form. Mrj interacts with Hsp70 proteins and acts as a chaperone by interfering with the aggregation of pathogenic Huntingtin. Unlike its mammalian homolog, we find Drosophila Mrj is neither an essential gene nor causes any gross neurodevelopmental defect. We observe a loss of Mrj results in a reduction in Orb2 oligomers. Further, Mrj knockout exhibits a deficit in long-term memory and our observations suggest Mrj is needed in mushroom body neurons for the regulation of long-term memory. Our work implicates a chaperone Mrj in mechanisms of memory regulation through controlling the oligomerization of Orb2A and its association with the translating ribosomes.
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Affiliation(s)
- Meghal Desai
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, India
| | - Hemant
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, India
| | - Ankita Deo
- Institute of Bioinformatics and Biotechnology (IBB), Savitribai Phule Pune University, Pune, India
| | - Jagyanseni Naik
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, India
| | - Prathamesh Dhamale
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, India
| | - Avinash Kshirsagar
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, India
| | - Tania Bose
- Institute of Bioinformatics and Biotechnology (IBB), Savitribai Phule Pune University, Pune, India
| | - Amitabha Majumdar
- National Centre for Cell Science, Savitribai Phule Pune University Campus, Pune, India
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13
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Yang Z, Wu Y, Liu H, He L, Deng X. AMYGNN: A Graph Convolutional Neural Network-Based Approach for Predicting Amyloid Formation from Polypeptides. J Chem Inf Model 2024; 64:1751-1762. [PMID: 38408296 DOI: 10.1021/acs.jcim.3c02035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
There has been an increasing interest in the use of amyloids for constructing various functional materials. The design of amyloid-associated functional materials requires the identification of the core peptide sequences as the fundamental building block. The existing computational methods are limited in terms of delineating polypeptides, the typical non-Euclidean structural data, and they fail to capture the dynamic interactions between amino acids due to ignoring the contextual information from surrounding amino acids. Here, we first propose the use of a state-of-the-art graph convolutional neural network for predicting the trends of amyloid formation from specific peptide sequences (AMYGNN) by abstracting each polypeptide as a graph, in which the constituting amino acids are viewed as nodes and edges characterizing the connections between pairs of amino acids are established when they meet a given distance threshold (Cα-Cα ≤ 5 Å). Our model achieves high performance with accuracy (0.9208), G-mean (0.9203), MCC (0.8417), and F1 (0.9235) in determining the characteristic peptide sequences to form amyloid. 32 of 534 crucial amino acid properties that greatly contribute to the formation of amyloids are ascertained, and the β-folding-like graph structure of a polypeptide is believed to be essential for the formation of amyloid. Our model enables the mapping of polypeptides with underlying interactions between amino acids and provides a quick and precise predictive framework for directing the construction of amyloid-associated functional materials.
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Affiliation(s)
- Zuojun Yang
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, China
- Guangdong Provincial Key Laboratory of Laser Life Science, and Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Yuhan Wu
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, China
- Guangdong Provincial Key Laboratory of Laser Life Science, and Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Hao Liu
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, China
- Guangdong Provincial Key Laboratory of Laser Life Science, and Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Li He
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, China
- Guangdong Provincial Key Laboratory of Laser Life Science, and Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Xiaoyuan Deng
- MOE Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, China
- Guangdong Provincial Key Laboratory of Laser Life Science, and Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China
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14
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Rinauro DJ, Chiti F, Vendruscolo M, Limbocker R. Misfolded protein oligomers: mechanisms of formation, cytotoxic effects, and pharmacological approaches against protein misfolding diseases. Mol Neurodegener 2024; 19:20. [PMID: 38378578 PMCID: PMC10877934 DOI: 10.1186/s13024-023-00651-2] [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] [Accepted: 08/17/2023] [Indexed: 02/22/2024] Open
Abstract
The conversion of native peptides and proteins into amyloid aggregates is a hallmark of over 50 human disorders, including Alzheimer's and Parkinson's diseases. Increasing evidence implicates misfolded protein oligomers produced during the amyloid formation process as the primary cytotoxic agents in many of these devastating conditions. In this review, we analyze the processes by which oligomers are formed, their structures, physicochemical properties, population dynamics, and the mechanisms of their cytotoxicity. We then focus on drug discovery strategies that target the formation of oligomers and their ability to disrupt cell physiology and trigger degenerative processes.
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Affiliation(s)
- Dillon J Rinauro
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Fabrizio Chiti
- Section of Biochemistry, Department of Experimental and Clinical Biomedical Sciences, University of Florence, 50134, Florence, Italy
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK.
| | - Ryan Limbocker
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY, 10996, USA.
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15
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Chen CC, Han J, Chinn CA, Rounds JS, Li X, Nikan M, Myszka M, Tong L, Passalacqua LFM, Bredy T, Wood MA, Luptak A. Inhibition of Cpeb3 ribozyme elevates CPEB3 protein expression and polyadenylation of its target mRNAs and enhances object location memory. eLife 2024; 13:e90116. [PMID: 38319152 PMCID: PMC10919898 DOI: 10.7554/elife.90116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 02/05/2024] [Indexed: 02/07/2024] Open
Abstract
A self-cleaving ribozyme that maps to an intron of the cytoplasmic polyadenylation element-binding protein 3 (Cpeb3) gene is thought to play a role in human episodic memory, but the underlying mechanisms mediating this effect are not known. We tested the activity of the murine sequence and found that the ribozyme's self-scission half-life matches the time it takes an RNA polymerase to reach the immediate downstream exon, suggesting that the ribozyme-dependent intron cleavage is tuned to co-transcriptional splicing of the Cpeb3 mRNA. Our studies also reveal that the murine ribozyme modulates maturation of its harboring mRNA in both cultured cortical neurons and the hippocampus: inhibition of the ribozyme using an antisense oligonucleotide leads to increased CPEB3 protein expression, which enhances polyadenylation and translation of localized plasticity-related target mRNAs, and subsequently strengthens hippocampal-dependent long-term memory. These findings reveal a previously unknown role for self-cleaving ribozyme activity in regulating experience-induced co-transcriptional and local translational processes required for learning and memory.
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Affiliation(s)
- Claire C Chen
- Department of Pharmaceutical Sciences, University of California, IrvineIrvineUnited States
| | - Joseph Han
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California, IrvineIrvineUnited States
| | - Carlene A Chinn
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California, IrvineIrvineUnited States
| | - Jacob S Rounds
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California, IrvineIrvineUnited States
| | - Xiang Li
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California, IrvineIrvineUnited States
| | | | - Marie Myszka
- Department of Chemistry, University of California, IrvineIrvineUnited States
| | - Liqi Tong
- Institute for Memory Impairments and Neurological Disorders, University of California, IrvineIrvineUnited States
| | - Luiz FM Passalacqua
- Department of Pharmaceutical Sciences, University of California, IrvineIrvineUnited States
| | - Timothy Bredy
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California, IrvineIrvineUnited States
| | - Marcelo A Wood
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California, IrvineIrvineUnited States
| | - Andrej Luptak
- Department of Pharmaceutical Sciences, University of California, IrvineIrvineUnited States
- Department of Chemistry, University of California, IrvineIrvineUnited States
- Department of Molecular Biology and Biochemistry, University of California, IrvineIrvineUnited States
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16
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Garcia-Pardo J, Ventura S. Cryo-EM structures of functional and pathological amyloid ribonucleoprotein assemblies. Trends Biochem Sci 2024; 49:119-133. [PMID: 37926650 DOI: 10.1016/j.tibs.2023.10.005] [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: 07/26/2023] [Revised: 10/05/2023] [Accepted: 10/06/2023] [Indexed: 11/07/2023]
Abstract
Amyloids are implicated in neurodegenerative and systemic diseases, yet they serve important functional roles in numerous organisms. Heterogeneous nuclear ribonucleoproteins (hnRNPs) represent a large family of RNA-binding proteins (RBPs) that control central events of RNA biogenesis in normal and diseased cellular conditions. Many of these proteins contain prion-like sequences of low complexity, which not only assemble into functional fibrils in response to cellular cues but can also lead to disease when missense mutations arise in their sequences. Recent advances in cryo-electron microscopy (cryo-EM) have provided unprecedented high-resolution structural insights into diverse amyloid assemblies formed by hnRNPs and structurally related RBPs, including TAR DNA-binding protein 43 (TDP-43), Fused in Sarcoma (FUS), Orb2, hnRNPA1, hnRNPA2, and hnRNPDL-2. This review provides a comprehensive overview of these structures and explores their functional and pathological implications.
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Affiliation(s)
- Javier Garcia-Pardo
- Institut de Biotecnologia i de Biomedicina (IBB) and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain.
| | - Salvador Ventura
- Institut de Biotecnologia i de Biomedicina (IBB) and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, 08193, Bellaterra, Barcelona, Spain.
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17
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Mishra S. Emerging Trends in Cryo-EM-based Structural Studies of Neuropathological Amyloids. J Mol Biol 2023; 435:168361. [PMID: 37949311 DOI: 10.1016/j.jmb.2023.168361] [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: 09/29/2023] [Revised: 11/02/2023] [Accepted: 11/03/2023] [Indexed: 11/12/2023]
Abstract
Tauopathies, synucleinopathies, Aβ amyloidosis, TDP-43 proteinopathies, and prion diseases- these neurodegenerative diseases have in common the formation of amyloid filaments rich in cross-β sheets. Cryo-electron microscopy now permits the visualization of amyloid assemblies at atomic resolution, ushering a wide range of structural studies on several of these poorly understood amyloidogenic proteins. Amyloids are polymorphic with minor modulations in reaction environment affecting the overall architecture of their assembly, making amyloids an extremely challenging venture for structure-based therapeutic intervention. In 2017, the first cryo-EM structure of tau filaments from an Alzheimer's disease-affected brain established that in vitro assemblies might not necessarily reflect the native amyloid fold. Since then, brain-derived amyloid structures for several proteins across many neurodegenerative diseases have uncovered the disease-relevant amyloid folds. It has now been shown for tauopathies, synucleinopathies and TDP-43 proteinopathies, that distinct amyloid folds of the same protein might be related to different diseases. Salient features of each of these brain-derived folds are discussed in detail. It was also recently observed that seeded aggregation does not necessarily replicate the brain-derived structural fold. Owing to high throughput structure determination, some of these native amyloid folds have also been successfully replicated in vitro. In vitro replication of disease-relevant filaments will aid development of imaging ligands and defibrillating drugs. Towards this direction, recent high-resolution structures of tau filaments with positron emission tomography tracers and a defibrillating drug are also discussed. This review summarizes and celebrates the recent advancements in structural understanding of neuropathological amyloid filaments using cryo-EM.
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Affiliation(s)
- Suman Mishra
- Molecular Biophysics Unit, Biological Sciences Division, Indian Institute of Science, Bengaluru 560 012, Karnataka, India.
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18
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Louros N, Schymkowitz J, Rousseau F. Mechanisms and pathology of protein misfolding and aggregation. Nat Rev Mol Cell Biol 2023; 24:912-933. [PMID: 37684425 DOI: 10.1038/s41580-023-00647-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/28/2023] [Indexed: 09/10/2023]
Abstract
Despite advances in machine learning-based protein structure prediction, we are still far from fully understanding how proteins fold into their native conformation. The conventional notion that polypeptides fold spontaneously to their biologically active states has gradually been replaced by our understanding that cellular protein folding often requires context-dependent guidance from molecular chaperones in order to avoid misfolding. Misfolded proteins can aggregate into larger structures, such as amyloid fibrils, which perpetuate the misfolding process, creating a self-reinforcing cascade. A surge in amyloid fibril structures has deepened our comprehension of how a single polypeptide sequence can exhibit multiple amyloid conformations, known as polymorphism. The assembly of these polymorphs is not a random process but is influenced by the specific conditions and tissues in which they originate. This observation suggests that, similar to the folding of native proteins, the kinetics of pathological amyloid assembly are modulated by interactions specific to cells and tissues. Here, we review the current understanding of how intrinsic protein conformational propensities are modulated by physiological and pathological interactions in the cell to shape protein misfolding and aggregation pathology.
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Affiliation(s)
- Nikolaos Louros
- Switch Laboratory, VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Joost Schymkowitz
- Switch Laboratory, VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.
- Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium.
| | - Frederic Rousseau
- Switch Laboratory, VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium.
- Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium.
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19
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Rosenberg GM, Abskharon R, Boyer DR, Ge P, Sawaya MR, Eisenberg DS. Fibril structures of TFG protein mutants validate the identification of TFG as a disease-related amyloid protein by the IMPAcT method. PNAS NEXUS 2023; 2:pgad402. [PMID: 38077690 PMCID: PMC10703350 DOI: 10.1093/pnasnexus/pgad402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 11/13/2023] [Indexed: 12/23/2023]
Abstract
We previously presented a bioinformatic method for identifying diseases that arise from a mutation in a protein's low-complexity domain that drives the protein into pathogenic amyloid fibrils. One protein so identified was the tropomyosin-receptor kinase-fused gene protein (TRK-fused gene protein or TFG). Mutations in TFG are associated with degenerative neurological conditions. Here, we present experimental evidence that confirms our prediction that these conditions are amyloid-related. We find that the low-complexity domain of TFG containing the disease-related mutations G269V or P285L forms amyloid fibrils, and we determine their structures using cryo-electron microscopy (cryo-EM). These structures are unmistakably amyloid in nature and confirm the propensity of the mutant TFG low-complexity domain to form amyloid fibrils. Also, despite resulting from a pathogenic mutation, the fibril structures bear some similarities to other amyloid structures that are thought to be nonpathogenic and even functional, but there are other factors that support these structures' relevance to disease, including an increased propensity to form amyloid compared with the wild-type sequence, structure-stabilizing influence from the mutant residues themselves, and double-protofilament amyloid cores. Our findings elucidate two potentially disease-relevant structures of a previously unknown amyloid and also show how the structural features of pathogenic amyloid fibrils may not conform to the features commonly associated with pathogenicity.
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Affiliation(s)
- Gregory M Rosenberg
- Department of Chemistry and Biochemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Department of Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Howard Hughes Medical Institute, UCLA, Los Angeles, CA 90095, USA
| | - Romany Abskharon
- Department of Chemistry and Biochemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Department of Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Howard Hughes Medical Institute, UCLA, Los Angeles, CA 90095, USA
| | - David R Boyer
- Department of Chemistry and Biochemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Department of Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Howard Hughes Medical Institute, UCLA, Los Angeles, CA 90095, USA
| | - Peng Ge
- Department of Chemistry and Biochemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Department of Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Howard Hughes Medical Institute, UCLA, Los Angeles, CA 90095, USA
| | - Michael R Sawaya
- Department of Chemistry and Biochemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Department of Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Howard Hughes Medical Institute, UCLA, Los Angeles, CA 90095, USA
| | - David S Eisenberg
- Department of Chemistry and Biochemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Department of Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA
- Howard Hughes Medical Institute, UCLA, Los Angeles, CA 90095, USA
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20
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Ottoz DSM, Tang LC, Dyatel AE, Jovanovic M, Berchowitz LE. Assembly and function of the amyloid-like translational repressor Rim4 is coupled with nutrient conditions. EMBO J 2023; 42:e113332. [PMID: 37921330 PMCID: PMC10690475 DOI: 10.15252/embj.2022113332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 09/20/2023] [Accepted: 09/25/2023] [Indexed: 11/04/2023] Open
Abstract
Amyloid-like protein assemblies have been associated with toxic phenotypes because of their repetitive and stable structure. However, evidence that cells exploit these structures to control function and activity of some proteins in response to stimuli has questioned this paradigm. How amyloid-like assembly can confer emergent functions and how cells couple assembly with environmental conditions remains unclear. Here, we study Rim4, an RNA-binding protein that forms translation-repressing assemblies during yeast meiosis. We demonstrate that in its assembled and repressive state, Rim4 binds RNA more efficiently than in its monomeric and idle state, revealing a causal connection between assembly and function. The Rim4-binding site location within the transcript dictates whether the assemblies can repress translation, underscoring the importance of the architecture of this RNA-protein structure for function. Rim4 assembly depends exclusively on its intrinsically disordered region and is prevented by the Ras/protein kinase A signaling pathway, which promotes growth and suppresses meiotic entry in yeast. Our results suggest a mechanism whereby cells couple a functional protein assembly with a stimulus to enforce a cell fate decision.
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Affiliation(s)
- Diana SM Ottoz
- Department of Genetics and Development, Hammer Health Sciences CenterColumbia University Irving Medical CenterNew YorkNYUSA
| | - Lauren C Tang
- Department of Biological SciencesColumbia UniversityNew YorkNYUSA
| | - Annie E Dyatel
- Department of Genetics and Development, Hammer Health Sciences CenterColumbia University Irving Medical CenterNew YorkNYUSA
| | - Marko Jovanovic
- Department of Biological SciencesColumbia UniversityNew YorkNYUSA
| | - Luke E Berchowitz
- Department of Genetics and Development, Hammer Health Sciences CenterColumbia University Irving Medical CenterNew YorkNYUSA
- Taub Institute for Research on Alzheimer's and the Aging BrainNew YorkNYUSA
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21
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Ramírez de Mingo D, López-García P, Vaquero ME, Hervás R, Laurents DV, Carrión-Vázquez M. Phase separation modulates the functional amyloid assembly of human CPEB3. Prog Neurobiol 2023; 231:102540. [PMID: 37898314 DOI: 10.1016/j.pneurobio.2023.102540] [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: 05/09/2023] [Revised: 09/15/2023] [Accepted: 10/21/2023] [Indexed: 10/30/2023]
Abstract
How functional amyloids are regulated to restrict their activity is poorly understood. The cytoplasmic polyadenylation element-binding protein 3 (CPEB3) is an RNA-binding protein that adopts an amyloid state key for memory persistence. Its monomer represses the translation of synaptic target mRNAs while phase separated, whereas its aggregated state acts as a translational activator. Here, we have explored the sequence-driven molecular determinants behind the functional aggregation of human CPEB3 (hCPEB3). We found that the intrinsically disordered region (IDR) of hCPEB3 encodes both an amyloidogenic and a phase separation domain, separated by a poly-A-rich region. The hCPEB3 amyloid core is composed by a hydrophobic region instead of the Q-rich stretch found in the Drosophila orthologue. The hCPEB3 phase separation domain relies on hydrophobic interactions with ionic strength dependence, and its droplet ageing process leads to a liquid-to-solid transition with the formation of a non-fibril-based hydrogel surrounded by starburst droplets. Furthermore, we demonstrate the differential behavior of the protein depending on its environment. Under physiological-like conditions, hCPEB3 can establish additional electrostatic interactions with ions, increasing the stability of its liquid droplets and driving a condensation-based amyloid pathway.
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Affiliation(s)
| | - Paula López-García
- Instituto Cajal, CSIC, Avenida Doctor Arce 37, Madrid 28002, Spain; PhD Program in Neuroscience, Universidad Autónoma de Madrid-Cajal Institute, Madrid 28029, Spain
| | | | - Rubén Hervás
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region of China
| | - Douglas V Laurents
- Instituto de Química Física "Blas Cabrera", CSIC, C/ Serrano 119, Madrid 28006, Spain
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22
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Galkin AP, Sysoev EI, Valina AA. Amyloids and prions in the light of evolution. Curr Genet 2023; 69:189-202. [PMID: 37165144 DOI: 10.1007/s00294-023-01270-6] [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: 04/14/2023] [Revised: 05/02/2023] [Accepted: 05/04/2023] [Indexed: 05/12/2023]
Abstract
Functional amyloids have been identified in a wide variety of organisms including bacteria, fungi, plants, and vertebrates. Intracellular and extracellular amyloid fibrils of different proteins perform storage, protective, structural, and regulatory functions. The structural organization of amyloid fibrils determines their unique physical and biochemical properties. The formation of these fibrillar structures can provide adaptive advantages that are picked up by natural selection. Despite the great interest in functional and pathological amyloids, questions about the conservatism of the amyloid properties of proteins and the regularities in the appearance of these fibrillar structures in evolution remain almost unexplored. Using bioinformatics approaches and summarizing the data published previously, we have shown that amyloid fibrils performing similar functions in different organisms have been arising repeatedly and independently in the course of evolution. On the other hand, we show that the amyloid properties of a number of bacterial and eukaryotic proteins are evolutionarily conserved. We also discuss the role of protein-based inheritance in the evolution of microorganisms. Considering that missense mutations and the emergence of prions cause the same consequences, we propose the concept that the formation of prions, similarly to mutations, generally causes a negative effect, although it can also lead to adaptations in rare cases. In general, our analysis revealed certain patterns in the emergence and spread of amyloid fibrillar structures in the course of evolution.
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Affiliation(s)
- Alexey P Galkin
- Vavilov Institute of General Genetics, St. Petersburg Branch, Russian Academy of Sciences, St. Petersburg, Russian Federation, 199034.
- Department of Genetics and Biotechnology, St. Petersburg State University, St. Petersburg, Russian Federation, 199034.
| | - Evgeniy I Sysoev
- Vavilov Institute of General Genetics, St. Petersburg Branch, Russian Academy of Sciences, St. Petersburg, Russian Federation, 199034
- Department of Genetics and Biotechnology, St. Petersburg State University, St. Petersburg, Russian Federation, 199034
| | - Anna A Valina
- Department of Genetics and Biotechnology, St. Petersburg State University, St. Petersburg, Russian Federation, 199034
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Kandola T, Venkatesan S, Zhang J, Lerbakken BT, Von Schulze A, Blanck JF, Wu J, Unruh JR, Berry P, Lange JJ, Box AC, Cook M, Sagui C, Halfmann R. Pathologic polyglutamine aggregation begins with a self-poisoning polymer crystal. eLife 2023; 12:RP86939. [PMID: 37921648 PMCID: PMC10624427 DOI: 10.7554/elife.86939] [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] [Indexed: 11/04/2023] Open
Abstract
A long-standing goal of amyloid research has been to characterize the structural basis of the rate-determining nucleating event. However, the ephemeral nature of nucleation has made this goal unachievable with existing biochemistry, structural biology, and computational approaches. Here, we addressed that limitation for polyglutamine (polyQ), a polypeptide sequence that causes Huntington's and other amyloid-associated neurodegenerative diseases when its length exceeds a characteristic threshold. To identify essential features of the polyQ amyloid nucleus, we used a direct intracellular reporter of self-association to quantify frequencies of amyloid appearance as a function of concentration, conformational templates, and rational polyQ sequence permutations. We found that nucleation of pathologically expanded polyQ involves segments of three glutamine (Q) residues at every other position. We demonstrate using molecular simulations that this pattern encodes a four-stranded steric zipper with interdigitated Q side chains. Once formed, the zipper poisoned its own growth by engaging naive polypeptides on orthogonal faces, in a fashion characteristic of polymer crystals with intramolecular nuclei. We further show that self-poisoning can be exploited to block amyloid formation, by genetically oligomerizing polyQ prior to nucleation. By uncovering the physical nature of the rate-limiting event for polyQ aggregation in cells, our findings elucidate the molecular etiology of polyQ diseases.
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Affiliation(s)
- Tej Kandola
- Stowers Institute for Medical ResearchKansas CityUnited States
- The Open UniversityMilton KeynesUnited Kingdom
| | | | - Jiahui Zhang
- Department of Physics, North Carolina State UniversityRaleighUnited States
| | | | | | | | - Jianzheng Wu
- Stowers Institute for Medical ResearchKansas CityUnited States
- Department of Biochemistry and Molecular Biology, University of Kansas Medical CenterKansas CityUnited States
| | - Jay R Unruh
- Stowers Institute for Medical ResearchKansas CityUnited States
| | - Paula Berry
- Stowers Institute for Medical ResearchKansas CityUnited States
| | - Jeffrey J Lange
- Stowers Institute for Medical ResearchKansas CityUnited States
| | - Andrew C Box
- Stowers Institute for Medical ResearchKansas CityUnited States
| | - Malcolm Cook
- Stowers Institute for Medical ResearchKansas CityUnited States
| | - Celeste Sagui
- Department of Physics, North Carolina State UniversityRaleighUnited States
| | - Randal Halfmann
- Stowers Institute for Medical ResearchKansas CityUnited States
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24
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Subbaiah S P V, Uttamrao PP, Das U, Sundaresan S, Rathinavelan T. Concentration and time-dependent amyloidogenic characteristics of intrinsically disordered N-terminal region of Saccharomyces cerevisiae Stm1. Front Microbiol 2023; 14:1206945. [PMID: 37928673 PMCID: PMC10620681 DOI: 10.3389/fmicb.2023.1206945] [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: 04/16/2023] [Accepted: 10/03/2023] [Indexed: 11/07/2023] Open
Abstract
Saccharomyces cerevisiae Stm1 protein is a ribosomal association factor, which plays an important role in preserving ribosomes in a nutrition-deprived environment. It is also shown to take part in apoptosis-like cell death. Stm1 N-terminal region (Stm1_N1-113) is shown to recognize purine motif DNA triplex and G-quadruplex. Circular dichroism (CD) spectra of Stm1_N1-113 (enriched in positively-charged Lysine and Arginine; negatively-charged Aspartate; polar-uncharged Threonine, Asparagine, Proline and Serine; hydrophobic Alanine, Valine, and Glycine) collected after 0 and 24 h indicate that the protein assumes beta-sheet conformation at the higher concentrations in contrast to intrinsically disordered conformation seen for its monomeric form found in the crystal structure. Thioflavin-T kinetics experiments indicate that the lag phase is influenced by the salt concentration. Atomic force microscopy (AFM) images collected for a variety of Stm1_N1-113 concentrations (in the range of 1-400 μM) in the presence of 150 mM NaCl at 0, 24, and 48 h indicate a threshold concentration requirement to observe the time-dependent amyloid formation. This is prominent seen at the physiological salt concentration of 150 mM NaCl with the fibrillation observed for 400 μM concentration at 48 h, whereas oligomerization or proto-fibrillation is seen for the other concentrations. Such concentration-dependent fibrillation of Stm1_N1-113 explains that amyloid fibrils formed during the overexpression of Stm1_N1-113 may act as a molecular device to trigger apoptosis-like cell death.
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Affiliation(s)
- Venkata Subbaiah S P
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Telangana, India
| | - Patil Pranita Uttamrao
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Telangana, India
| | - Uttam Das
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Telangana, India
| | - Sruthi Sundaresan
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Telangana, India
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25
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Voigt B, Bhatia T, Hesselbarth J, Baumann M, Schmidt C, Ott M, Balbach J. The Prenucleation Equilibrium of the Parathyroid Hormone Determines the Critical Aggregation Concentration and Amyloid Fibril Nucleation. Chemphyschem 2023; 24:e202300439. [PMID: 37477386 DOI: 10.1002/cphc.202300439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 07/18/2023] [Accepted: 07/18/2023] [Indexed: 07/22/2023]
Abstract
Nucleation and growth of amyloid fibrils were found to only occur in supersaturated solutions above a critical concentration (ccrit ). The biophysical meaning of ccrit remained mostly obscure, since typical low values of ccrit in the sub-μM range hamper investigations of potential oligomeric states and their structure. Here, we investigate the parathyroid hormone PTH84 as an example of a functional amyloid fibril forming peptide with a comparably high ccrit of 67±21 μM. We describe a complex concentration dependent prenucleation ensemble of oligomers of different sizes and secondary structure compositions and highlight the occurrence of a trimer and tetramer at ccrit as possible precursors for primary fibril nucleation. Furthermore, the soluble state found in equilibrium with fibrils adopts to the prenucleation state present at ccrit . Our study sheds light onto early events of amyloid formation directly related to the critical concentration and underlines oligomer formation as a key feature of fibril nucleation. Our results contribute to a deeper understanding of the determinants of supersaturated peptide solutions. In the current study we present a biophysical approach to investigate ccrit of amyloid fibril formation of PTH84 in terms of secondary structure, cluster size and residue resolved intermolecular interactions during oligomer formation. Throughout the investigated range of concentrations (1 μM to 500 μM) we found different states of oligomerization with varying ability to contribute to primary fibril nucleation and with a concentration dependent equilibrium. In this context, we identified the previously described ccrit of PTH84 to mark a minimum concentration for the formation of homo-trimers/tetramers. These investigations allowed us to characterize molecular interactions of various oligomeric states that are further converted into elongation competent fibril nuclei during the lag phase of a functional amyloid forming peptide.
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Affiliation(s)
- Bruno Voigt
- Martin Luther University Halle-Wittenberg, Institute of Physics, Betty-Heimann-Straße 7, 06120, Halle, Germany
| | - Twinkle Bhatia
- Martin Luther University Halle-Wittenberg, Institute of Biochemistry and Biotechnology, Kurt-Mothes-Straße 3, 06120, Halle, Germany
| | - Julia Hesselbarth
- present address: Johannes Gutenberg University Mainz, Institute of Chemistry - Biochemistry, Biocenter II, Hanns-Dieter-Hüsch-Weg 17, 55128, Mainz, Germany
- Martin Luther University Halle-Wittenberg, Interdisciplinary Research Center HALOmem, Institute of Biochemistry and Biotechnology, Kurt-Mothes-Straße 3a, 06120, Halle, Germany
| | - Monika Baumann
- Martin Luther University Halle-Wittenberg, Institute of Physics, Betty-Heimann-Straße 7, 06120, Halle, Germany
| | - Carla Schmidt
- present address: Johannes Gutenberg University Mainz, Institute of Chemistry - Biochemistry, Biocenter II, Hanns-Dieter-Hüsch-Weg 17, 55128, Mainz, Germany
- Martin Luther University Halle-Wittenberg, Interdisciplinary Research Center HALOmem, Institute of Biochemistry and Biotechnology, Kurt-Mothes-Straße 3a, 06120, Halle, Germany
| | - Maria Ott
- Martin Luther University Halle-Wittenberg, Institute of Biochemistry and Biotechnology, Kurt-Mothes-Straße 3, 06120, Halle, Germany
| | - Jochen Balbach
- Martin Luther University Halle-Wittenberg, Institute of Physics, Betty-Heimann-Straße 7, 06120, Halle, Germany
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26
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Zhang J, Zhang X, Gao Y, Li L, Bai L, Wang L, Qiao Y, Wang X, Liang Z, Xu JT. Neuralized1-Mediated CPEB3 Ubiquitination in the Spinal Dorsal Horn Contributes to the Pathogenesis of Neuropathic Pain in Rats. ACS Chem Neurosci 2023; 14:3418-3430. [PMID: 37644621 DOI: 10.1021/acschemneuro.3c00313] [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] [Indexed: 08/31/2023] Open
Abstract
Compelling evidence has shown that Neuralized1 (Neurl1) facilitates hippocampal-dependent memory storage by modulating cytoplasmic polyadenylation element-binding protein 3 (CPEB3)-dependent protein synthesis. In the current study, we investigated the role of Neurl1 in the pathogenesis of neuropathic pain and the underlying mechanisms. The neuropathic pain was evaluated by lumbar 5 spinal nerve ligation (SNL) in rats. Immunofluorescence staining, Western blotting, qRT-PCR, and coimmunoprecipitation (Co-IP) were performed to investigate the underlying mechanisms. Our results showed that SNL led to an increase of Neurl1 in the spinal dorsal horn. Spinal microinjection of AAV-EGFP-Neurl1 shRNA alleviated mechanical allodynia; decreased the level of CPEB3 ubiquitination; inhibited the production of GluA1, GluA2, and PSD95; and reduced GluA1-containing AMPA receptors in the membrane of the dorsal horn following SNL. Knockdown of spinal CPEB3 decreased the production of GluA1, GluA2, and PSD95 in the dorsal horn and attenuated abnormal pain after SNL. Overexpression of Neurl1 in the dorsal horn resulted in pain-related hypersensitivity in naïve rats; raised the level of CPEB3 ubiquitination; increased the production of GluA1, GluA2, and PSD95; and augmented GluA1-containing AMPA receptors in the membrane in the dorsal horn. Moreover, spinal Neurl1 overexpression-induced mechanical allodynia in naïve rats was partially reversed by repeated intrathecal injections of CPEB3 siRNA. Collectively, our results suggest that SNL-induced upregulation of Neurl1 through CPEB3 ubiquitination-dependent production of GluA1, GluA2, and PSD95 in the dorsal horn contributes to the pathogenesis of neuropathic pain in rats. Targeting spinal Neurl1 might be a promising therapeutic strategy for the treatment of neuropathic pain.
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Affiliation(s)
- Jian Zhang
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, China
| | - Xuan Zhang
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, China
| | - Yan Gao
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, China
| | - Liren Li
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, China
| | - Liying Bai
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, China
- Department of Anesthesiology, Pain and Perioperative Medicine, The First Affiliated Hospital, Zhengzhou University, 1 Jianshe East Road, Zhengzhou 450052, China
| | - Li Wang
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, China
| | - Yiming Qiao
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, China
| | - Xueli Wang
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, China
| | - Zongyi Liang
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, China
| | - Ji-Tian Xu
- Department of Physiology and Neurobiology, School of Basic Medical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, China
- Neuroscience Research Institute, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, China
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27
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Nowakowska AW, Wojciechowski JW, Szulc N, Kotulska M. The role of tandem repeats in bacterial functional amyloids. J Struct Biol 2023; 215:108002. [PMID: 37482232 DOI: 10.1016/j.jsb.2023.108002] [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: 03/24/2023] [Revised: 07/05/2023] [Accepted: 07/20/2023] [Indexed: 07/25/2023]
Abstract
Repetitivity and modularity of proteins are two related notions incorporated into multiple evolutionary concepts. We discuss whether they may also be essential for functional amyloids. Amyloids are proteins that create very regular and usually highly insoluble fibrils, which are often associated with neurodegeneration. However, recent discoveries showed that amyloid structure of a protein could also be beneficial and desired, e.g., to promote cell adhesion. Functional amyloids are proteins which differ in their characteristics from pathological amyloids, so that the fibril formation could be more under control of an organism. We propose that repeats in the sequence could regulate the aggregation propensity of these proteins. The inclusion of multiple symmetric interactions, due to the presence of the repeats, could be supporting and strengthening the desirable structural properties of functional amyloids. Our results show that tandem repeats in bacterial functional amyloids have a distinct characteristic. The pattern of repeats supports the appropriate level of fibril formation and better controllability of fibril stability. The repeats tend to be more imperfect, which attenuates excessive aggregation propensity. Their desired structure and function are also reinforced by their amino acid profile. Although in the study we focused on bacterial functional amyloids, due to their importance in biofilm formation, we propose that similar mechanisms could be employed in other functional amyloids which are designed by evolution to aggregate in a desirable manner, but not necessarily in pathological amyloids.
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Affiliation(s)
- Alicja W Nowakowska
- Wrocław University of Science and Technology, Department of Biomedical Engineering, Poland.
| | - Jakub W Wojciechowski
- Wrocław University of Science and Technology, Department of Biomedical Engineering, Poland
| | - Natalia Szulc
- Wrocław University of Science and Technology, Department of Biomedical Engineering, Poland; Wrocław University of Environmental and Life Sciences, Department of Physics and Biophysics, Poland; LPCT, CNRS, Universite de Lorraine, F-54000 Nancy, France
| | - Malgorzata Kotulska
- Wrocław University of Science and Technology, Department of Biomedical Engineering, Poland.
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28
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Bhopatkar AA, Kayed R. Flanking regions, amyloid cores, and polymorphism: the potential interplay underlying structural diversity. J Biol Chem 2023; 299:105122. [PMID: 37536631 PMCID: PMC10482755 DOI: 10.1016/j.jbc.2023.105122] [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: 04/26/2023] [Revised: 07/10/2023] [Accepted: 07/28/2023] [Indexed: 08/05/2023] Open
Abstract
The β-sheet-rich amyloid core is the defining feature of protein aggregates associated with neurodegenerative disorders. Recent investigations have revealed that there exist multiple examples of the same protein, with the same sequence, forming a variety of amyloid cores with distinct structural characteristics. These structural variants, termed as polymorphs, are hypothesized to influence the pathological profile and the progression of different neurodegenerative diseases, giving rise to unique phenotypic differences. Thus, identifying the origin and properties of these structural variants remain a focus of studies, as a preliminary step in the development of therapeutic strategies. Here, we review the potential role of the flanking regions of amyloid cores in inducing polymorphism. These regions, adjacent to the amyloid cores, show a preponderance for being structurally disordered, imbuing them with functional promiscuity. The dynamic nature of the flanking regions can then manifest in the form of conformational polymorphism of the aggregates. We take a closer look at the sequences flanking the amyloid cores, followed by a review of the polymorphic aggregates of the well-characterized proteins amyloid-β, α-synuclein, Tau, and TDP-43. We also consider different factors that can potentially influence aggregate structure and how these regions can be viewed as novel targets for therapeutic strategies by utilizing their unique structural properties.
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Affiliation(s)
- Anukool A Bhopatkar
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas, USA; Departments of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Rakez Kayed
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas, USA; Departments of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas, USA.
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29
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Coronel R, Bernabeu-Zornoza A, Palmer C, González-Sastre R, Rosca A, Mateos-Martínez P, López-Alonso V, Liste I. Amyloid Precursor Protein (APP) Regulates Gliogenesis and Neurogenesis of Human Neural Stem Cells by Several Signaling Pathways. Int J Mol Sci 2023; 24:12964. [PMID: 37629148 PMCID: PMC10455174 DOI: 10.3390/ijms241612964] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/11/2023] [Accepted: 08/18/2023] [Indexed: 08/27/2023] Open
Abstract
Numerous studies have focused on the pathophysiological role of amyloid precursor protein (APP) because the proteolytic processing of APP to β-amyloid (Aβ) peptide is a central event in Alzheimer's disease (AD). However, many authors consider that alterations in the physiological functions of APP are likely to play a key role in AD. Previous studies in our laboratory revealed that APP plays an important role in the differentiation of human neural stem cells (hNSCs), favoring glial differentiation (gliogenesis) and preventing their differentiation toward a neuronal phenotype (neurogenesis). In the present study, we have evaluated the effects of APP overexpression in hNSCs at a global gene level by a transcriptomic analysis using the massive RNA sequencing (RNA-seq) technology. Specifically, we have focused on differentially expressed genes that are related to neuronal and glial differentiation processes, as well as on groups of differentially expressed genes associated with different signaling pathways, in order to find a possible interaction between them and APP. Our data indicate a differential expression in genes related to Notch, Wnt, PI3K-AKT, and JAK-STAT signaling, among others. Knowledge of APP biological functions, as well as the possible signaling pathways that could be related to this protein, are essential to advance our understanding of AD.
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Affiliation(s)
- Raquel Coronel
- Unidad de Regeneración Neural, Unidad Funcional de Investigación de Enfermedades Crónicas, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain; (A.B.-Z.); (C.P.); (R.G.-S.); (A.R.); (P.M.-M.)
- Departamento de Biología de Sistemas, Facultad de Medicina y Ciencias de la Salud, Universidad de Alcalá, Alcalá de Henares, 28871 Madrid, Spain
| | - Adela Bernabeu-Zornoza
- Unidad de Regeneración Neural, Unidad Funcional de Investigación de Enfermedades Crónicas, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain; (A.B.-Z.); (C.P.); (R.G.-S.); (A.R.); (P.M.-M.)
| | - Charlotte Palmer
- Unidad de Regeneración Neural, Unidad Funcional de Investigación de Enfermedades Crónicas, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain; (A.B.-Z.); (C.P.); (R.G.-S.); (A.R.); (P.M.-M.)
| | - Rosa González-Sastre
- Unidad de Regeneración Neural, Unidad Funcional de Investigación de Enfermedades Crónicas, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain; (A.B.-Z.); (C.P.); (R.G.-S.); (A.R.); (P.M.-M.)
- Unidad de Biología Computacional, Unidad Funcional de Investigación de Enfermedades Crónicas, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain;
| | - Andreea Rosca
- Unidad de Regeneración Neural, Unidad Funcional de Investigación de Enfermedades Crónicas, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain; (A.B.-Z.); (C.P.); (R.G.-S.); (A.R.); (P.M.-M.)
| | - Patricia Mateos-Martínez
- Unidad de Regeneración Neural, Unidad Funcional de Investigación de Enfermedades Crónicas, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain; (A.B.-Z.); (C.P.); (R.G.-S.); (A.R.); (P.M.-M.)
| | - Victoria López-Alonso
- Unidad de Biología Computacional, Unidad Funcional de Investigación de Enfermedades Crónicas, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain;
| | - Isabel Liste
- Unidad de Regeneración Neural, Unidad Funcional de Investigación de Enfermedades Crónicas, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain; (A.B.-Z.); (C.P.); (R.G.-S.); (A.R.); (P.M.-M.)
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30
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Davis RL. Learning and memory using Drosophila melanogaster: a focus on advances made in the fifth decade of research. Genetics 2023; 224:iyad085. [PMID: 37212449 PMCID: PMC10411608 DOI: 10.1093/genetics/iyad085] [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: 02/16/2023] [Accepted: 05/03/2023] [Indexed: 05/23/2023] Open
Abstract
In the last decade, researchers using Drosophila melanogaster have made extraordinary progress in uncovering the mysteries underlying learning and memory. This progress has been propelled by the amazing toolkit available that affords combined behavioral, molecular, electrophysiological, and systems neuroscience approaches. The arduous reconstruction of electron microscopic images resulted in a first-generation connectome of the adult and larval brain, revealing complex structural interconnections between memory-related neurons. This serves as substrate for future investigations on these connections and for building complete circuits from sensory cue detection to changes in motor behavior. Mushroom body output neurons (MBOn) were discovered, which individually forward information from discrete and non-overlapping compartments of the axons of mushroom body neurons (MBn). These neurons mirror the previously discovered tiling of mushroom body axons by inputs from dopamine neurons and have led to a model that ascribes the valence of the learning event, either appetitive or aversive, to the activity of different populations of dopamine neurons and the balance of MBOn activity in promoting avoidance or approach behavior. Studies of the calyx, which houses the MBn dendrites, have revealed a beautiful microglomeruluar organization and structural changes of synapses that occur with long-term memory (LTM) formation. Larval learning has advanced, positioning it to possibly lead in producing new conceptual insights due to its markedly simpler structure over the adult brain. Advances were made in how cAMP response element-binding protein interacts with protein kinases and other transcription factors to promote the formation of LTM. New insights were made on Orb2, a prion-like protein that forms oligomers to enhance synaptic protein synthesis required for LTM formation. Finally, Drosophila research has pioneered our understanding of the mechanisms that mediate permanent and transient active forgetting, an important function of the brain along with acquisition, consolidation, and retrieval. This was catalyzed partly by the identification of memory suppressor genes-genes whose normal function is to limit memory formation.
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Affiliation(s)
- Ronald L Davis
- Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, University of Florida, 130 Scripps Way, Jupiter, FL 33458, USA
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31
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Horváth D, Dürvanger Z, K Menyhárd D, Sulyok-Eiler M, Bencs F, Gyulai G, Horváth P, Taricska N, Perczel A. Polymorphic amyloid nanostructures of hormone peptides involved in glucose homeostasis display reversible amyloid formation. Nat Commun 2023; 14:4621. [PMID: 37528104 PMCID: PMC10394066 DOI: 10.1038/s41467-023-40294-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 07/21/2023] [Indexed: 08/03/2023] Open
Abstract
A large group of hormones are stored as amyloid fibrils in acidic secretion vesicles before they are released into the bloodstream and readopt their functional state. Here, we identify an evolutionarily conserved hexapeptide sequence as the major aggregation-prone region (APR) of gastrointestinal peptides of the glucagon family: xFxxWL. We determine nine polymorphic crystal structures of the APR segments of glucagon-like peptides 1 and 2, and exendin and its derivatives. We follow amyloid formation by CD, FTIR, ThT assays, and AFM. We propose that the pH-dependent changes of the protonation states of glutamate/aspartate residues of APRs initiate switching between the amyloid and the folded, monomeric forms of the hormones. We find that pH sensitivity diminishes in the absence of acidic gatekeepers and amyloid formation progresses over a broad pH range. Our results highlight the dual role of short aggregation core motifs in reversible amyloid formation and receptor binding.
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Affiliation(s)
- Dániel Horváth
- ELKH-ELTE Protein Modeling Research Group ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
| | - Zsolt Dürvanger
- ELKH-ELTE Protein Modeling Research Group ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
- Laboratory of Structural Chemistry and Biology ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
| | - Dóra K Menyhárd
- ELKH-ELTE Protein Modeling Research Group ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
- Laboratory of Structural Chemistry and Biology ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
| | - Máté Sulyok-Eiler
- Laboratory of Structural Chemistry and Biology ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
- Hevesy György PhD School of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
| | - Fruzsina Bencs
- Laboratory of Structural Chemistry and Biology ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
- Hevesy György PhD School of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
| | - Gergő Gyulai
- Laboratory of Interfaces and Nanostructures, Institute of Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
| | - Péter Horváth
- Department of Pharmaceutical Chemistry, Semmelweis University, Hőgyes Endre utca 9, Budapest, 1092, Hungary
| | - Nóra Taricska
- ELKH-ELTE Protein Modeling Research Group ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary
| | - András Perczel
- ELKH-ELTE Protein Modeling Research Group ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary.
- Laboratory of Structural Chemistry and Biology ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary.
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32
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Liu Q, Fong B, Yoo S, Unruh JR, Guo F, Yu Z, Chen J, Si K, Li R, Zhou C. Nascent mitochondrial proteins initiate the localized condensation of cytosolic protein aggregates on the mitochondrial surface. Proc Natl Acad Sci U S A 2023; 120:e2300475120. [PMID: 37494397 PMCID: PMC10401023 DOI: 10.1073/pnas.2300475120] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 06/21/2023] [Indexed: 07/28/2023] Open
Abstract
Eukaryotes organize cellular contents into membrane-bound organelles and membrane-less condensates, for example, protein aggregates. An unsolved question is why the ubiquitously distributed proteins throughout the cytosol give rise to spatially localized protein aggregates on the organellar surface, like mitochondria. We report that the mitochondrial import receptor Tom70 is involved in the localized condensation of protein aggregates in budding yeast and human cells. This is because misfolded cytosolic proteins do not autonomously aggregate in vivo; instead, they are recruited to the condensation sites initiated by Tom70's substrates (nascent mitochondrial proteins) on the organellar membrane using multivalent hydrophobic interactions. Knocking out Tom70 partially impairs, while overexpressing Tom70 increases the formation and association between cytosolic protein aggregates and mitochondria. In addition, ectopic targeting Tom70 and its substrates to the vacuole surface is able to redirect the localized aggregation from mitochondria to the vacuolar surface. Although other redundant mechanisms may exist, this nascent mitochondrial proteins-based initiation of protein aggregation likely explains the localized condensation of otherwise ubiquitously distributed molecules on the mitochondria. Disrupting the mitochondrial association of aggregates impairs their asymmetric retention during mitosis and reduces the mitochondrial import of misfolded proteins, suggesting a proteostasis role of the organelle-condensate interactions.
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Affiliation(s)
- Qingqing Liu
- Buck Institute for Research on Aging, Novato, CA94945
| | - Benjamin Fong
- Buck Institute for Research on Aging, Novato, CA94945
| | - Seungmin Yoo
- Buck Institute for Research on Aging, Novato, CA94945
| | - Jay R. Unruh
- Stowers Institute for Medical Research, Kansas City, MO64110
| | - Fengli Guo
- Stowers Institute for Medical Research, Kansas City, MO64110
| | - Zulin Yu
- Stowers Institute for Medical Research, Kansas City, MO64110
| | - Jingjing Chen
- Stowers Institute for Medical Research, Kansas City, MO64110
| | - Kausik Si
- Stowers Institute for Medical Research, Kansas City, MO64110
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS66160
| | - Rong Li
- Department of Cell Biology, Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD21205
- Department of Chemical and Biomolecular Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD21218
- Mechanobiology Institute and Department of Biological Science, National University of Singapore, Singapore117411, Singapore
| | - Chuankai Zhou
- Buck Institute for Research on Aging, Novato, CA94945
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33
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Kandola T, Venkatesan S, Zhang J, Lerbakken B, Schulze AV, Blanck JF, Wu J, Unruh J, Berry P, Lange JJ, Box A, Cook M, Sagui C, Halfmann R. Pathologic polyglutamine aggregation begins with a self-poisoning polymer crystal. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.20.533418. [PMID: 36993401 PMCID: PMC10055281 DOI: 10.1101/2023.03.20.533418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
A long-standing goal of amyloid research has been to characterize the structural basis of the rate-determining nucleating event. However, the ephemeral nature of nucleation has made this goal unachievable with existing biochemistry, structural biology, and computational approaches. Here, we addressed that limitation for polyglutamine (polyQ), a polypeptide sequence that causes Huntington's and other amyloid-associated neurodegenerative diseases when its length exceeds a characteristic threshold. To identify essential features of the polyQ amyloid nucleus, we used a direct intracellular reporter of self-association to quantify frequencies of amyloid appearance as a function of concentration, conformational templates, and rational polyQ sequence permutations. We found that nucleation of pathologically expanded polyQ involves segments of three glutamine (Q) residues at every other position. We demonstrate using molecular simulations that this pattern encodes a four-stranded steric zipper with interdigitated Q side chains. Once formed, the zipper poisoned its own growth by engaging naive polypeptides on orthogonal faces, in a fashion characteristic of polymer crystals with intramolecular nuclei. We further show that self-poisoning can be exploited to block amyloid formation, by genetically oligomerizing polyQ prior to nucleation. By uncovering the physical nature of the rate-limiting event for polyQ aggregation in cells, our findings elucidate the molecular etiology of polyQ diseases.
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Affiliation(s)
- Tej Kandola
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
- The Open University, Milton Keyes, MK7 6AA, UK
| | | | - Jiahui Zhang
- Department of Physics, North Carolina State University, Raleigh, NC 27695, USA
| | | | - Alex Von Schulze
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Jillian F Blanck
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Jianzheng Wu
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Jay Unruh
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Paula Berry
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Jeffrey J Lange
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Andrew Box
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Malcolm Cook
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
| | - Celeste Sagui
- Department of Physics, North Carolina State University, Raleigh, NC 27695, USA
| | - Randal Halfmann
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
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34
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Stewart RK, Nguyen P, Laederach A, Volkan PC, Sawyer JK, Fox DT. Orb2 enables rare-codon-enriched mRNA expression during Drosophila neuron differentiation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.26.550700. [PMID: 37546801 PMCID: PMC10402044 DOI: 10.1101/2023.07.26.550700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Regulation of codon optimality is an increasingly appreciated layer of cell- and tissue-specific protein expression control. Here, we use codon-modified reporters to show that differentiation of Drosophila neural stem cells into neurons enables protein expression from rare-codon-enriched genes. From a candidate screen, we identify the cytoplasmic polyadenylation element binding (CPEB) protein Orb2 as a positive regulator of rare-codon-dependent expression in neurons. Using RNA sequencing, we reveal that Orb2-upregulated mRNAs in the brain with abundant Orb2 binding sites have a rare-codon bias. From these Orb2-regulated mRNAs, we demonstrate that rare-codon enrichment is important for expression control and social behavior function of the metabotropic glutamate receptor (mGluR). Our findings reveal a molecular mechanism by which neural stem cell differentiation shifts genetic code regulation to enable critical mRNA and protein expression.
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35
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Chen CC, Han J, Chinn CA, Rounds JS, Li X, Nikan M, Myszka M, Tong L, Passalacqua LFM, Bredy TW, Wood MA, Lupták A. Inhibition of CPEB3 ribozyme elevates CPEB3 protein expression and polyadenylation of its target mRNAs, and enhances object location memory. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.07.543953. [PMID: 37333407 PMCID: PMC10274809 DOI: 10.1101/2023.06.07.543953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
A self-cleaving ribozyme that maps to an intron of the cytoplasmic polyadenylation element binding protein 3 (CPEB3) gene is thought to play a role in human episodic memory, but the underlying mechanisms mediating this effect are not known. We tested the activity of the murine sequence and found that the ribozyme's self-scission half-life matches the time it takes an RNA polymerase to reach the immediate downstream exon, suggesting that the ribozyme-dependent intron cleavage is tuned to co-transcriptional splicing of the CPEB3 mRNA. Our studies also reveal that the murine ribozyme modulates maturation of its harboring mRNA in both cultured cortical neurons and the hippocampus: inhibition of the ribozyme using an antisense oligonucleotide leads to increased CPEB3 protein expression, which enhances polyadenylation and translation of localized plasticity-related target mRNAs, and subsequently strengthens hippocampal-dependent long-term memory. These findings reveal a previously unknown role for self-cleaving ribozyme activity in regulating experience-induced co-transcriptional and local translational processes required for learning and memory.
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Affiliation(s)
- Claire C. Chen
- Department of Pharmaceutical Sciences, University of California–Irvine, Irvine, California 92697, United States
| | - Joseph Han
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Carlene A. Chinn
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Jacob S. Rounds
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Xiang Li
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Mehran Nikan
- Ionis Pharmaceuticals, 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Marie Myszka
- Department of Chemistry, University of California–Irvine, Irvine, California 92697, United States
| | - Liqi Tong
- Institute for Memory Impairments and Neurological Disorders, University of California–Irvine, Irvine, California 92697, United States
| | - Luiz F. M. Passalacqua
- Department of Pharmaceutical Sciences, University of California–Irvine, Irvine, California 92697, United States
| | - Timothy W. Bredy
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Marcelo A. Wood
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, University of California–Irvine, Irvine, California 92697, United States
| | - Andrej Lupták
- Department of Pharmaceutical Sciences, University of California–Irvine, Irvine, California 92697, United States
- Department of Chemistry, University of California–Irvine, Irvine, California 92697, United States
- Department of Molecular Biology and Biochemistry, University of California–Irvine, Irvine, California 92697, United States
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36
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Buchanan JA, Varghese NR, Johnston CL, Sunde M. Functional Amyloids: Where Supramolecular Amyloid Assembly Controls Biological Activity or Generates New Functionality. J Mol Biol 2023; 435:167919. [PMID: 37330295 DOI: 10.1016/j.jmb.2022.167919] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 12/05/2022] [Accepted: 12/05/2022] [Indexed: 06/19/2023]
Abstract
Functional amyloids are a rapidly expanding class of fibrillar protein structures, with a core cross-β scaffold, where novel and advantageous biological function is generated by the assembly of the amyloid. The growing number of amyloid structures determined at high resolution reveal how this supramolecular template both accommodates a wide variety of amino acid sequences and also imposes selectivity on the assembly process. The amyloid fibril can no longer be considered a generic aggregate, even when associated with disease and loss of function. In functional amyloids the polymeric β-sheet rich structure provides multiple different examples of unique control mechanisms and structures that are finely tuned to deliver assembly or disassembly in response to physiological or environmental cues. Here we review the range of mechanisms at play in natural, functional amyloids, where tight control of amyloidogenicity is achieved by environmental triggers of conformational change, proteolytic generation of amyloidogenic fragments, or heteromeric seeding and amyloid fibril stability. In the amyloid fibril form, activity can be regulated by pH, ligand binding and higher order protofilament or fibril architectures that impact the arrangement of associated domains and amyloid stability. The growing understanding of the molecular basis for the control of structure and functionality delivered by natural amyloids in nearly all life forms should inform the development of therapies for amyloid-associated diseases and guide the design of innovative biomaterials.
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Affiliation(s)
- Jessica A Buchanan
- School of Medical Sciences and Sydney Nano, The University of Sydney, NSW 2006, Australia.
| | - Nikhil R Varghese
- School of Medical Sciences and Sydney Nano, The University of Sydney, NSW 2006, Australia.
| | - Caitlin L Johnston
- School of Medical Sciences and Sydney Nano, The University of Sydney, NSW 2006, Australia.
| | - Margaret Sunde
- School of Medical Sciences and Sydney Nano, The University of Sydney, NSW 2006, Australia.
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37
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Sleutel M, Pradhan B, Volkov AN, Remaut H. Structural analysis and architectural principles of the bacterial amyloid curli. Nat Commun 2023; 14:2822. [PMID: 37198180 DOI: 10.1038/s41467-023-38204-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 04/20/2023] [Indexed: 05/19/2023] Open
Abstract
Two decades have passed since the initial proposition that amyloids are not only (toxic) byproducts of an unintended aggregation cascade, but that they can also be produced by an organism to serve a defined biological function. That revolutionary idea was borne out of the realization that a large fraction of the extracellular matrix that holds Gram-negative cells into a persistent biofilm is composed of protein fibers (curli; tafi) with cross-β architecture, nucleation-dependent polymerization kinetics and classic amyloid tinctorial properties. The list of proteins shown to form so-called functional amyloid fibers in vivo has greatly expanded over the years, but detailed structural insights have not followed at a similar pace in part due to the associated experimental barriers. Here we combine extensive AlphaFold2 modelling and cryo-electron transmission microscopy to propose an atomic model of curli protofibrils, and their higher modes of organization. We uncover an unexpected structural diversity of curli building blocks and fibril architectures. Our results allow for a rationalization of the extreme physico-chemical robustness of curli, as well as earlier observations of inter-species curli promiscuity, and should facilitate further engineering efforts to expand the repertoire of curli-based functional materials.
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Affiliation(s)
- Mike Sleutel
- Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, Belgium.
- Structural and Molecular Microbiology, VIB-VUB Center for Structural Biology, Brussels, Belgium.
| | - Brajabandhu Pradhan
- Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, Belgium
- Structural and Molecular Microbiology, VIB-VUB Center for Structural Biology, Brussels, Belgium
| | - Alexander N Volkov
- Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, Belgium
- Jean Jeener NMR Center, Brussel, Belgium
| | - Han Remaut
- Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, Belgium.
- Structural and Molecular Microbiology, VIB-VUB Center for Structural Biology, Brussels, Belgium.
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38
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Sahin C, Motso A, Gu X, Feyrer H, Lama D, Arndt T, Rising A, Gese GV, Hällberg BM, Marklund EG, Schafer NP, Petzold K, Teilum K, Wolynes PG, Landreh M. Mass Spectrometry of RNA-Binding Proteins during Liquid-Liquid Phase Separation Reveals Distinct Assembly Mechanisms and Droplet Architectures. J Am Chem Soc 2023; 145:10659-10668. [PMID: 37145883 DOI: 10.1021/jacs.3c00932] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Liquid-liquid phase separation (LLPS) of heterogeneous ribonucleoproteins (hnRNPs) drives the formation of membraneless organelles, but structural information about their assembled states is still lacking. Here, we address this challenge through a combination of protein engineering, native ion mobility mass spectrometry, and molecular dynamics simulations. We used an LLPS-compatible spider silk domain and pH changes to control the self-assembly of the hnRNPs FUS, TDP-43, and hCPEB3, which are implicated in neurodegeneration, cancer, and memory storage. By releasing the proteins inside the mass spectrometer from their native assemblies, we could monitor conformational changes associated with liquid-liquid phase separation. We find that FUS monomers undergo an unfolded-to-globular transition, whereas TDP-43 oligomerizes into partially disordered dimers and trimers. hCPEB3, on the other hand, remains fully disordered with a preference for fibrillar aggregation over LLPS. The divergent assembly mechanisms revealed by ion mobility mass spectrometry of soluble protein species that exist under LLPS conditions suggest structurally distinct complexes inside liquid droplets that may impact RNA processing and translation depending on biological context.
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Affiliation(s)
- Cagla Sahin
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
- Structural Biology and NMR Laboratory and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes vej 5, 2200 Copenhagen, Denmark
| | - Aikaterini Motso
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
| | - Xinyu Gu
- Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Hannes Feyrer
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
| | - Dilraj Lama
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
| | - Tina Arndt
- Department of Biosciences and Nutrition, Karolinska Institutet, S-141 57 Huddinge, Sweden
| | - Anna Rising
- Department of Biosciences and Nutrition, Karolinska Institutet, S-141 57 Huddinge, Sweden
- Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Box 7011, S-750 07 Uppsala, Sweden
| | - Genis Valentin Gese
- Department of Cell and Molecular Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 171 65 Stockholm, Sweden
| | - B Martin Hällberg
- Department of Cell and Molecular Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 171 65 Stockholm, Sweden
| | - Erik G Marklund
- Department of Chemistry - BMC, Uppsala University, Box 576, 751 23 Uppsala, Sweden
| | - Nicholas P Schafer
- Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Katja Petzold
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
- Department of Medical Biochemistry and Microbiology, Uppsala University, 751 24 Uppsala, Sweden
| | - Kaare Teilum
- Structural Biology and NMR Laboratory and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Ole Maaløes vej 5, 2200 Copenhagen, Denmark
| | - Peter G Wolynes
- Center for Theoretical Biological Physics, Rice University, Houston, Texas 77005, United States
- Department of Chemistry, Rice University, Houston, Texas 77005, United States
| | - Michael Landreh
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet - Biomedicum, Solnavägen 9, 17165 Solna, Sweden
- Department of Cell- and Molecular Biology, Uppsala University, Box 596, 751 24 Uppsala, Sweden
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39
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Segal D, Maier S, Mastromarco GJ, Qian WW, Nabeel-Shah S, Lee H, Moore G, Lacoste J, Larsen B, Lin ZY, Selvabaskaran A, Liu K, Smibert C, Zhang Z, Greenblatt J, Peng J, Lee HO, Gingras AC, Taipale M. A central chaperone-like role for 14-3-3 proteins in human cells. Mol Cell 2023; 83:974-993.e15. [PMID: 36931259 DOI: 10.1016/j.molcel.2023.02.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 11/30/2022] [Accepted: 02/15/2023] [Indexed: 03/18/2023]
Abstract
14-3-3 proteins are highly conserved regulatory proteins that interact with hundreds of structurally diverse clients and act as central hubs of signaling networks. However, how 14-3-3 paralogs differ in specificity and how they regulate client protein function are not known for most clients. Here, we map the interactomes of all human 14-3-3 paralogs and systematically characterize the effect of disrupting these interactions on client localization. The loss of 14-3-3 binding leads to the coalescence of a large fraction of clients into discrete foci in a client-specific manner, suggesting a central chaperone-like function for 14-3-3 proteins. Congruently, the engraftment of 14-3-3 binding motifs to nonclients can suppress their aggregation or phase separation. Finally, we show that 14-3-3s negatively regulate the localization of the RNA-binding protein SAMD4A to cytoplasmic granules and inhibit its activity as a translational repressor. Our work suggests that 14-3-3s have a more prominent role as chaperone-like molecules than previously thought.
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Affiliation(s)
- Dmitri Segal
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Stefan Maier
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, ON M5G 1X5, Canada
| | | | - Wesley Wei Qian
- Department of Computer Science, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Syed Nabeel-Shah
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Hyunmin Lee
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Computer Science, University of Toronto, Toronto, ON M5S 3G4, Canada
| | - Gaelen Moore
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Jessica Lacoste
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Brett Larsen
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, ON M5G 1X5, Canada
| | - Zhen-Yuan Lin
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, ON M5G 1X5, Canada
| | - Abeeshan Selvabaskaran
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Karen Liu
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Craig Smibert
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Zhaolei Zhang
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada; Department of Computer Science, University of Toronto, Toronto, ON M5S 3G4, Canada
| | - Jack Greenblatt
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada
| | - Jian Peng
- Department of Computer Science, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Hyun O Lee
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Anne-Claude Gingras
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health System, Toronto, ON M5G 1X5, Canada.
| | - Mikko Taipale
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON M5S 3E1, Canada.
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40
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Development of Small Molecules Targeting α-Synuclein Aggregation: A Promising Strategy to Treat Parkinson’s Disease. Pharmaceutics 2023; 15:pharmaceutics15030839. [PMID: 36986700 PMCID: PMC10059018 DOI: 10.3390/pharmaceutics15030839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 02/24/2023] [Accepted: 02/28/2023] [Indexed: 03/08/2023] Open
Abstract
Parkinson’s disease, the second most common neurodegenerative disorder worldwide, is characterized by the accumulation of protein deposits in the dopaminergic neurons. These deposits are primarily composed of aggregated forms of α-Synuclein (α-Syn). Despite the extensive research on this disease, only symptomatic treatments are currently available. However, in recent years, several compounds, mainly of an aromatic character, targeting α-Syn self-assembly and amyloid formation have been identified. These compounds, discovered by different approaches, are chemically diverse and exhibit a plethora of mechanisms of action. This work aims to provide a historical overview of the physiopathology and molecular aspects associated with Parkinson’s disease and the current trends in small compound development to target α-Syn aggregation. Although these molecules are still under development, they constitute an important step toward discovering effective anti-aggregational therapies for Parkinson’s disease.
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41
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Mullapudi V, Vaquer-Alicea J, Bommareddy V, Vega AR, Ryder BD, White CL, Diamond MI, Joachimiak LA. Network of hotspot interactions cluster tau amyloid folds. Nat Commun 2023; 14:895. [PMID: 36797278 PMCID: PMC9935906 DOI: 10.1038/s41467-023-36572-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 02/06/2023] [Indexed: 02/18/2023] Open
Abstract
Cryogenic electron microscopy has revealed unprecedented molecular insight into the conformations of β-sheet-rich protein amyloids linked to neurodegenerative diseases. It remains unknown how a protein can adopt a diversity of folds and form multiple distinct fibrillar structures. Here we develop an in silico alanine scan method to estimate the relative energetic contribution of each amino acid in an amyloid assembly. We apply our method to twenty-seven ex vivo and in vitro fibril structural polymorphs of the microtubule-associated protein tau. We uncover networks of energetically important interactions involving amyloid-forming motifs that stabilize the different fibril folds. We evaluate our predictions in cellular and in vitro aggregation assays. Using a machine learning approach, we classify the structures based on residue energetics to identify distinguishing and unifying features. Our energetic profiling suggests that minimal sequence elements control the stability of tau fibrils, allowing future design of protein sequences that fold into unique structures.
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Affiliation(s)
- Vishruth Mullapudi
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Jaime Vaquer-Alicea
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Vaibhav Bommareddy
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Anthony R Vega
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Bryan D Ryder
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
- Molecular Biophysics Graduate Program, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Charles L White
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Marc I Diamond
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Lukasz A Joachimiak
- Center for Alzheimer's and Neurodegenerative Diseases, Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA.
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42
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Nielsen AW, Sari L, Fraser R, Lin MM. Protein aggregates thermodynamically order regardless of sequence. Proteins 2022; 91:705-711. [PMID: 36576407 DOI: 10.1002/prot.26460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 11/23/2022] [Accepted: 12/22/2022] [Indexed: 12/29/2022]
Abstract
Proteins can aggregate into disordered aggregates or ordered assemblies such as amyloid fibrils. These two distinct phases serve differing roles in function and disease. How protein sequence determines the preferred phase is unknown. Here we establish a statistical mechanical disorder-to-order transition condition for compact polymer aggregates, including proteins. The theory produces a simple universal equation determining the favored phase as a function of temperature, polymer length, and interaction energy variance. We show that the sequence-dependent energy variance is efficiently calculated using atomistic simulations, so that the theory has no adjustable parameters. The equation accurately predicts experimental length-dependent crystallization temperatures of synthetic polymers. The equation also predicts that all protein sequences that aggregate will also favor ordering. Consequently, energy must be expended to maintain the steady-state disordered phase if it is not kinetically metastable on physiological timescales. More broadly, the theory suggests that aggregates of organic polymers will generally tend to order on habitable planets.
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Affiliation(s)
- Aleksandra W Nielsen
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Levent Sari
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Rowan Fraser
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Milo M Lin
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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43
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Kehrer T, Cupic A, Ye C, Yildiz S, Bouhhadou M, Crossland NA, Barrall E, Cohen P, Tseng A, Çağatay T, Rathnasinghe R, Flores D, Jangra S, Alam F, Mena N, Aslam S, Saqi A, Marin A, Rutkowska M, Ummadi MR, Pisanelli G, Richardson RB, Veit EC, Fabius JM, Soucheray M, Polacco BJ, Evans MJ, Swaney DL, Gonzalez-Reiche AS, Sordillo EM, van Bakel H, Simon V, Zuliani-Alvarez L, Fontoura BMA, Rosenberg BR, Krogan NJ, Martinez-Sobrido L, García-Sastre A, Miorin L. Impact of SARS-CoV-2 ORF6 and its variant polymorphisms on host responses and viral pathogenesis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2022:2022.10.18.512708. [PMID: 36299428 DOI: 10.1101/2022.12.07.519389] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
UNLABELLED We and others have previously shown that the SARS-CoV-2 accessory protein ORF6 is a powerful antagonist of the interferon (IFN) signaling pathway by directly interacting with Nup98-Rae1 at the nuclear pore complex (NPC) and disrupting bidirectional nucleo-cytoplasmic trafficking. In this study, we further assessed the role of ORF6 during infection using recombinant SARS-CoV-2 viruses carrying either a deletion or a well characterized M58R loss-of-function mutation in ORF6. We show that ORF6 plays a key role in the antagonism of IFN signaling and in viral pathogenesis by interfering with karyopherin(importin)-mediated nuclear import during SARS-CoV-2 infection both in vitro , and in the Syrian golden hamster model in vivo . In addition, we found that ORF6-Nup98 interaction also contributes to inhibition of cellular mRNA export during SARS-CoV-2 infection. As a result, ORF6 expression significantly remodels the host cell proteome upon infection. Importantly, we also unravel a previously unrecognized function of ORF6 in the modulation of viral protein expression, which is independent of its function at the nuclear pore. Lastly, we characterized the ORF6 D61L mutation that recently emerged in Omicron BA.2 and BA.4 and demonstrated that it is able to disrupt ORF6 protein functions at the NPC and to impair SARS-CoV-2 innate immune evasion strategies. Importantly, the now more abundant Omicron BA.5 lacks this loss-of-function polymorphism in ORF6. Altogether, our findings not only further highlight the key role of ORF6 in the antagonism of the antiviral innate immune response, but also emphasize the importance of studying the role of non-spike mutations to better understand the mechanisms governing differential pathogenicity and immune evasion strategies of SARS-CoV-2 and its evolving variants. ONE SENTENCE SUMMARY SARS-CoV-2 ORF6 subverts bidirectional nucleo-cytoplasmic trafficking to inhibit host gene expression and contribute to viral pathogenesis.
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44
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A structural dynamics model for how CPEB3 binding to SUMO2 can regulate translational control in dendritic spines. PLoS Comput Biol 2022; 18:e1010657. [DOI: 10.1371/journal.pcbi.1010657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 11/18/2022] [Accepted: 10/14/2022] [Indexed: 11/09/2022] Open
Abstract
A prion-like RNA-binding protein, CPEB3, can regulate local translation in dendritic spines. CPEB3 monomers repress translation, whereas CPEB3 aggregates activate translation of its target mRNAs. However, the CPEB3 aggregates, as long-lasting prions, may raise the problem of unregulated translational activation. Here, we propose a computational model of the complex structure between CPEB3 RNA-binding domain (CPEB3-RBD) and small ubiquitin-like modifier protein 2 (SUMO2). Free energy calculations suggest that the allosteric effect of CPEB3-RBD/SUMO2 interaction can amplify the RNA-binding affinity of CPEB3. Combining with previous experimental observations on the SUMOylation mode of CPEB3, this model suggests an equilibrium shift of mRNA from binding to deSUMOylated CPEB3 aggregates to binding to SUMOylated CPEB3 monomers in basal synapses. This work shows how a burst of local translation in synapses can be silenced following a stimulation pulse, and explores the CPEB3/SUMO2 interplay underlying the structural change of synapses and the formation of long-term memories.
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45
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Matlahov I, Boatz JC, C.A. van der Wel P. Selective observation of semi-rigid non-core residues in dynamically complex mutant huntingtin protein fibrils. J Struct Biol X 2022; 6:100077. [PMID: 36419510 PMCID: PMC9677204 DOI: 10.1016/j.yjsbx.2022.100077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 09/20/2022] [Accepted: 11/07/2022] [Indexed: 11/13/2022] Open
Abstract
Mutant huntingtin exon 1 fibrils feature a broad range of molecular dynamics. Molecular motion is coupled to water dynamics outside the fiber core. Dynamics-based spectral editing ssNMR reveals mobile non-core residues. Intermediate-motion selection via dipolar dephasing of rigid sites. Semi-mobile glutamines outside the fiber core observed and identified.
Many amyloid-forming proteins, which are normally intrinsically disordered, undergo a disorder-to-order transition to form fibrils with a rigid β-sheet core flanked by disordered domains. Solid-state NMR (ssNMR) and cryogenic electron microscopy (cryoEM) excel at resolving the rigid structures within amyloid cores but studying the dynamically disordered domains remains challenging. This challenge is exemplified by mutant huntingtin exon 1 (HttEx1), which self-assembles into pathogenic neuronal inclusions in Huntington disease (HD). The mutant protein’s expanded polyglutamine (polyQ) segment forms a fibril core that is rigid and sequestered from the solvent. Beyond the core, solvent-exposed surface residues mediate biological interactions and other properties of fibril polymorphs. Here we deploy magic angle spinning ssNMR experiments to probe for semi-rigid residues proximal to the fibril core and examine how solvent dynamics impact the fibrils’ segmental dynamics. Dynamic spectral editing (DYSE) 2D ssNMR based on a combination of cross-polarization (CP) ssNMR with selective dipolar dephasing reveals the weak signals of solvent-mobilized glutamine residues, while suppressing the normally strong background of rigid core signals. This type of ‘intermediate motion selection’ (IMS) experiment based on cross-polarization (CP) ssNMR, is complementary to INEPT- and CP-based measurements that highlight highly flexible or highly rigid protein segments, respectively. Integration of the IMS-DYSE element in standard CP-based ssNMR experiments permits the observation of semi-rigid residues in a variety of contexts, including in membrane proteins and protein complexes. We discuss the relevance of semi-rigid solvent-facing residues outside the fibril core to the latter’s detection with specific dyes and positron emission tomography tracers.
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46
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Bowler JT, Sawaya MR, Boyer DR, Cascio D, Bali M, Eisenberg DS. Micro-electron diffraction structure of the aggregation-driving N-terminus of Drosophila neuronal protein Orb2A reveals amyloid-like β-sheets. J Biol Chem 2022; 298:102396. [PMID: 35988647 PMCID: PMC9556795 DOI: 10.1016/j.jbc.2022.102396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 11/26/2022] Open
Abstract
Amyloid protein aggregation is commonly associated with progressive neurodegenerative diseases, however not all amyloid fibrils are pathogenic. The neuronal cytoplasmic polyadenylation element binding (CPEB) protein is a regulator of synaptic mRNA translation, and has been shown to form functional amyloid aggregates that stabilize long-term memory. In adult Drosophila neurons, the CPEB homolog Orb2 is expressed as two isoforms, of which the Orb2B isoform is far more abundant, but the rarer Orb2A isoform is required to initiate Orb2 aggregation. The N-terminus is a distinctive feature of the Orb2A isoform and is critical for its aggregation. Intriguingly, replacement of phenylalanine in the 5th position of Orb2A with tyrosine (F5Y) in Drosophila impairs stabilization of long-term memory. The structure of endogenous Orb2B fibers was recently determined by cryo-EM, but the structure adopted by fibrillar Orb2A is less certain. Here we use micro-electron diffraction to determine the structure of the first nine N-terminal residues of Orb2A, at a resolution of 1.05 Å. We find that this segment (which we term M9I) forms an amyloid-like array of parallel in-register β-sheets, which interact through side chain interdigitation of aromatic and hydrophobic residues. Our structure provides an explanation for the decreased aggregation observed for the F5Y mutant, and offers a hypothesis for how the addition of a single atom (the tyrosyl oxygen) affects long-term memory. We also propose a structural model of Orb2A that integrates our structure of the M9I segment with the published Orb2B cryo-EM structure.
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Affiliation(s)
- Jeannette T Bowler
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute.
| | - Michael R Sawaya
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute
| | - David R Boyer
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute
| | - Duilio Cascio
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute
| | - Manya Bali
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute
| | - David S Eisenberg
- Molecular Biology Institute, University of California, Los Angeles; Howard Hughes Medical Institute.
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Siemer AB. What makes functional amyloids work? Crit Rev Biochem Mol Biol 2022; 57:399-411. [PMID: 35997712 PMCID: PMC9588633 DOI: 10.1080/10409238.2022.2113030] [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: 01/25/2022] [Revised: 06/29/2022] [Accepted: 08/10/2022] [Indexed: 01/27/2023]
Abstract
Although first described in the context of disease, cross-β (amyloid) fibrils have also been found as functional entities in all kingdoms of life. However, what are the specific properties of the cross-β fibril motif that convey biological function, make them especially suited for their particular purpose, and distinguish them from other fibrils found in biology? This review approaches these questions by arguing that cross-β fibrils are highly periodic, stable, and self-templating structures whose formation is accompanied by substantial conformational change that leads to a multimerization of their core and framing sequences. A discussion of each of these properties is followed by selected examples of functional cross-β fibrils that show how function is usually achieved by leveraging many of these properties.
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Affiliation(s)
- Ansgar B Siemer
- Department of Physiology and Neuroscience, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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48
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Liu Y, Wang Y, Tong C, Wei G, Ding F, Sun Y. Molecular Insights into the Self-Assembly of Block Copolymer Suckerin Polypeptides into Nanoconfined β-Sheets. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2202642. [PMID: 35901284 PMCID: PMC9420834 DOI: 10.1002/smll.202202642] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 06/27/2022] [Indexed: 06/15/2023]
Abstract
Suckerin in squid sucker ring teeth is a block-copolymer peptide comprised of two repeating modules-the alanine and histidine-rich M1 and the glycine-rich M2. Suckerin self-assemblies display excellent thermo-plasticity and pH-responsive properties, along with the high biocompatibility, biodegradability, and sustainability. However, the self-assembly mechanism and the detailed role of each module are still elusive, limiting the capability of applying and manipulating such biomaterials. Here, the self-assembly dynamics of the two modules and two minimalist suckerin-mimetic block-copolymers, M1-M2-M1 and M2-M1-M2, in silico is investigated. The simulation results demonstrate that M2 has a stronger self-association but weaker β-sheet propensities than M1. The high self-assembly propensity of M2 allows the minimalist block-copolymer peptides to coalesce with microphase separation, enabling the formation of nanoconfined β-sheets in the matrix formed by M1-M2 contacts. Since these glycine-rich fragments with scatted hydrophobic and aromatic residues are building blocks of many other block-copolymer peptides, the study suggests that these modules function as the "molecular glue" in addition to the flexible linker or spacer to drive the self-assembly and microphase separation. The uncovered molecular insights may help understand the structure and function of suckerin and also aid in the design of functional block-copolymer peptides for nanotechnology and biomedicine applications.
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Affiliation(s)
- Yuying Liu
- Department of Physics, Ningbo University, Ningbo 315211, China
| | - Ying Wang
- Department of Physics, Ningbo University, Ningbo 315211, China
| | - Chaohui Tong
- Department of Physics, Ningbo University, Ningbo 315211, China
| | - Guanghong Wei
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, USA
| | - Yunxiang Sun
- Department of Physics, Ningbo University, Ningbo 315211, China
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, USA
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49
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Bücker R, Seuring C, Cazey C, Veith K, García-Alai M, Grünewald K, Landau M. The Cryo-EM structures of two amphibian antimicrobial cross-β amyloid fibrils. Nat Commun 2022; 13:4356. [PMID: 35896552 PMCID: PMC9329304 DOI: 10.1038/s41467-022-32039-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 07/13/2022] [Indexed: 12/14/2022] Open
Abstract
The amyloid-antimicrobial link hypothesis is based on antimicrobial properties found in human amyloids involved in neurodegenerative and systemic diseases, along with amyloidal structural properties found in antimicrobial peptides (AMPs). Supporting this hypothesis, we here determined the fibril structure of two AMPs from amphibians, uperin 3.5 and aurein 3.3, by cryogenic electron microscopy (cryo-EM), revealing amyloid cross-β fibrils of mated β-sheets at atomic resolution. Uperin 3.5 formed a 3-blade symmetrical propeller of nine peptides per fibril layer including tight β-sheet interfaces. This cross-β cryo-EM structure complements the cross-α fibril conformation previously determined by crystallography, substantiating a secondary structure switch mechanism of uperin 3.5. The aurein 3.3 arrangement consisted of six peptides per fibril layer, all showing kinked β-sheets allowing a rounded compactness of the fibril. The kinked β-sheets are similar to LARKS (Low-complexity, Amyloid-like, Reversible, Kinked Segments) found in human functional amyloids. In this work the authors provide high-resolution structural support for the amyloid-antimicrobial link via functional amyloids displaying propeller-like and kinked cross-β fibrils.
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Affiliation(s)
- Robert Bücker
- Centre for Structural Systems Biology, Hamburg, Germany.,Department of Chemistry, University of Hamburg, Hamburg, Germany.,Rigaku Europe SE, Neu-Isenburg, Germany.,Leibniz Institute of Virology, Hamburg, Germany
| | - Carolin Seuring
- Centre for Structural Systems Biology, Hamburg, Germany.,Department of Chemistry, University of Hamburg, Hamburg, Germany.,Leibniz Institute of Virology, Hamburg, Germany
| | - Cornelia Cazey
- Centre for Structural Systems Biology, Hamburg, Germany.,Department of Chemistry, University of Hamburg, Hamburg, Germany
| | - Katharina Veith
- European Molecular Biology Laboratory, EMBL Hamburg, Hamburg, Germany
| | - Maria García-Alai
- Centre for Structural Systems Biology, Hamburg, Germany.,European Molecular Biology Laboratory, EMBL Hamburg, Hamburg, Germany
| | - Kay Grünewald
- Centre for Structural Systems Biology, Hamburg, Germany. .,Department of Chemistry, University of Hamburg, Hamburg, Germany. .,Leibniz Institute of Virology, Hamburg, Germany. .,Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK.
| | - Meytal Landau
- Centre for Structural Systems Biology, Hamburg, Germany. .,European Molecular Biology Laboratory, EMBL Hamburg, Hamburg, Germany. .,Department of Biology, Technion-Israel Institute of Technology, Haifa, 3200003, Israel.
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50
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Amyloid Properties of the FXR1 Protein Are Conserved in Evolution of Vertebrates. Int J Mol Sci 2022; 23:ijms23147997. [PMID: 35887344 PMCID: PMC9319111 DOI: 10.3390/ijms23147997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/16/2022] [Accepted: 07/18/2022] [Indexed: 12/10/2022] Open
Abstract
Functional amyloids are fibrillary proteins with a cross-β structure that play a structural or regulatory role in pro- and eukaryotes. Previously, we have demonstrated that the RNA-binding FXR1 protein functions in an amyloid form in the rat brain. This RNA-binding protein plays an important role in the regulation of long-term memory, emotions, and cancer. Here, we evaluate the amyloid properties of FXR1 in organisms representing various classes of vertebrates. We show the colocalization of FXR1 with amyloid-specific dyes in the neurons of amphibians, reptiles, and birds. Moreover, FXR1, as with other amyloids, forms detergent-resistant insoluble aggregates in all studied animals. The FXR1 protein isolated by immunoprecipitation from the brains of different vertebrate species forms fibrils, which show yellow-green birefringence after staining with Congo red. Our data indicate that in the evolution of vertebrates, FXR1 acquired amyloid properties at least 365 million years ago. Based on the obtained data, we discuss the possible role of FXR1 amyloid fibrils in the regulation of vital processes in the brain of vertebrates.
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