1
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Norrild RK, Mason TO, Boyens-Thiele L, Ray S, Mortensen JB, Fritsch AW, Iglesias-Artola JM, Klausen LK, Stender EGP, Jensen H, Buell AK. Taylor Dispersion-Induced Phase Separation for the Efficient Characterisation of Protein Condensate Formation. Angew Chem Int Ed Engl 2024; 63:e202404018. [PMID: 38593269 DOI: 10.1002/anie.202404018] [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: 02/27/2024] [Revised: 04/08/2024] [Accepted: 04/08/2024] [Indexed: 04/11/2024]
Abstract
Biomolecular condensates have emerged as important structures in cellular function and disease, and are thought to form through liquid-liquid phase separation (LLPS). Thorough and efficient in vitro experiments are therefore needed to elucidate the driving forces of protein LLPS and the possibility to modulate it with drugs. Here we present Taylor dispersion-induced phase separation (TDIPS), a method to robustly measure condensation phenomena using a commercially available microfluidic platform. It uses only nanoliters of sample, does not require extrinsic fluorescent labels, and is straightforward to implement. We demonstrate TDIPS by screening the phase behaviour of two proteins that form biomolecular condensates in vivo, PGL-3 and Ddx4. Uniquely accessible to this method, we find an unexpected re-entrant behaviour at very low ionic strength, where LLPS is inhibited for both proteins. TDIPS can also probe the reversibility of assemblies, which was shown for both α-synuclein and for lysozyme, relevant for health and biotechnology, respectively. Finally, we highlight how effective inhibition concentrations and partitioning of LLPS-modifying compounds can be screened highly efficiently.
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Affiliation(s)
- Rasmus K Norrild
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 227, 2800, Kgs. Lyngby, Denmark
| | - Thomas O Mason
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 227, 2800, Kgs. Lyngby, Denmark
| | - Lars Boyens-Thiele
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 227, 2800, Kgs. Lyngby, Denmark
| | - Soumik Ray
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 227, 2800, Kgs. Lyngby, Denmark
| | - Joachim B Mortensen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 227, 2800, Kgs. Lyngby, Denmark
| | - Anatol W Fritsch
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, 01307, Dresden, Germany
| | - Juan M Iglesias-Artola
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, 01307, Dresden, Germany
| | - Louise K Klausen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 227, 2800, Kgs. Lyngby, Denmark
| | | | - Henrik Jensen
- FIDA Biosystems Aps, Generatorvej 6 A+B, 2860, Søborg, Denmark
| | - Alexander K Buell
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 227, 2800, Kgs. Lyngby, Denmark
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2
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Jambon-Puillet E, Testa A, Lorenz C, Style RW, Rebane AA, Dufresne ER. Phase-separated droplets swim to their dissolution. Nat Commun 2024; 15:3919. [PMID: 38724503 PMCID: PMC11082165 DOI: 10.1038/s41467-024-47889-y] [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: 10/30/2023] [Accepted: 04/15/2024] [Indexed: 05/12/2024] Open
Abstract
Biological macromolecules can condense into liquid domains. In cells, these condensates form membraneless organelles that can organize chemical reactions. However, little is known about the physical consequences of chemical activity in and around condensates. Working with model bovine serum albumin (BSA) condensates, we show that droplets swim along chemical gradients. Active BSA droplets loaded with urease swim toward each other. Passive BSA droplets show diverse responses to externally applied gradients of the enzyme's substrate and products. In all these cases, droplets swim toward solvent conditions that favor their dissolution. We call this behavior "dialytaxis", and expect it to be generic, as conditions which favor dissolution typically reduce interfacial tension, whose gradients are well-known to drive droplet motion through the Marangoni effect. These results could potentially suggest alternative physical mechanisms for active transport in living cells, and may enable the design of fluid micro-robots.
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Affiliation(s)
- Etienne Jambon-Puillet
- Department of Materials, ETH Zürich, Zürich, Switzerland
- LadHyX, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France
| | - Andrea Testa
- Department of Materials, ETH Zürich, Zürich, Switzerland
| | - Charlotta Lorenz
- Department of Materials, ETH Zürich, Zürich, Switzerland
- Department of Materials Science and Engineering, Department of Physics, Cornell University, Ithaca, NY, USA
| | - Robert W Style
- Department of Materials, ETH Zürich, Zürich, Switzerland
| | - Aleksander A Rebane
- Department of Materials, ETH Zürich, Zürich, Switzerland
- Life Molecules and Materials Lab, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Eric R Dufresne
- Department of Materials, ETH Zürich, Zürich, Switzerland.
- Department of Materials Science and Engineering, Department of Physics, Cornell University, Ithaca, NY, USA.
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3
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Karger S, Miali ME, Solomonov A, Eliaz D, Varsano N, Shimanovich U. Protein Compartments Modulate Fibrillar Self-Assembly. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2308069. [PMID: 38148317 DOI: 10.1002/smll.202308069] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 12/04/2023] [Indexed: 12/28/2023]
Abstract
A notable feature of complex cellular environments is protein-rich compartments that are formed via liquid-liquid phase separation. Recent studies have shown that these biomolecular condensates can play both promoting and inhibitory roles in fibrillar protein self-assembly, a process that is linked to Alzheimer's, Parkinson's, Huntington's, and various prion diseases. Yet, the exact regulatory role of these condensates in protein aggregation remains unknown. By employing microfluidics to create artificial protein compartments, the self-assembly behavior of the fibrillar protein lysozyme within them can be characterized. It is observed that the volumetric parameters of protein-rich compartments can change the kinetics of protein self-assembly. Depending on the change in compartment parameters, the lysozyme fibrillation process either accelerated or decelerated. Furthermore, the results confirm that the volumetric parameters govern not only the nucleation and growth phases of the fibrillar aggregates but also affect the crosstalk between the protein-rich and protein-poor phases. The appearance of phase-separated compartments in the vicinity of natively folded protein complexes triggers their abrupt percolation into the compartments' core and further accelerates protein aggregation. Overall, the results of the study shed more light on the complex behavior and functions of protein-rich phases and, importantly, on their interaction with the surrounding environment.
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Affiliation(s)
- Shay Karger
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Marco E Miali
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Aleksei Solomonov
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Dror Eliaz
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Neta Varsano
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Ulyana Shimanovich
- Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science, Rehovot, 7610001, Israel
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4
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Alfano C, Fichou Y, Huber K, Weiss M, Spruijt E, Ebbinghaus S, De Luca G, Morando MA, Vetri V, Temussi PA, Pastore A. Molecular Crowding: The History and Development of a Scientific Paradigm. Chem Rev 2024; 124:3186-3219. [PMID: 38466779 PMCID: PMC10979406 DOI: 10.1021/acs.chemrev.3c00615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 02/13/2024] [Accepted: 02/26/2024] [Indexed: 03/13/2024]
Abstract
It is now generally accepted that macromolecules do not act in isolation but "live" in a crowded environment, that is, an environment populated by numerous different molecules. The field of molecular crowding has its origins in the far 80s but became accepted only by the end of the 90s. In the present issue, we discuss various aspects that are influenced by crowding and need to consider its effects. This Review is meant as an introduction to the theme and an analysis of the evolution of the crowding concept through time from colloidal and polymer physics to a more biological perspective. We introduce themes that will be more thoroughly treated in other Reviews of the present issue. In our intentions, each Review may stand by itself, but the complete collection has the aspiration to provide different but complementary perspectives to propose a more holistic view of molecular crowding.
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Affiliation(s)
- Caterina Alfano
- Structural
Biology and Biophysics Unit, Fondazione
Ri.MED, 90100 Palermo, Italy
| | - Yann Fichou
- CNRS,
Bordeaux INP, CBMN UMR 5248, IECB, University
of Bordeaux, F-33600 Pessac, France
| | - Klaus Huber
- Department
of Chemistry, University of Paderborn, 33098 Paderborn, Germany
| | - Matthias Weiss
- Experimental
Physics I, Physics of Living Matter, University
of Bayreuth, 95440 Bayreuth, Germany
| | - Evan Spruijt
- Institute
for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Simon Ebbinghaus
- Lehrstuhl
für Biophysikalische Chemie and Research Center Chemical Sciences
and Sustainability, Research Alliance Ruhr, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Giuseppe De Luca
- Dipartimento
di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche, Università degli Studi di Palermo, Viale delle Scienze, 90128 Palermo, Italy
| | | | - Valeria Vetri
- Dipartimento
di Fisica e Chimica − Emilio Segrè, Università degli Studi di Palermo, Viale delle Scienze, 90128 Palermo, Italy
| | | | - Annalisa Pastore
- King’s
College London, Denmark
Hill Campus, SE5 9RT London, United Kingdom
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5
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Qian D, Ausserwoger H, Sneideris T, Farag M, Pappu RV, Knowles TPJ. Dominance Analysis: A formalism to uncover dominant energetic contributions to biomolecular condensate formation in multicomponent systems. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.12.544666. [PMID: 38562796 PMCID: PMC10983860 DOI: 10.1101/2023.06.12.544666] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Phase separation in aqueous solutions of macromolecules is thought to underlie the generation of biomolecular condensates in cells. Condensates are membraneless bodies, representing dense, macromolecule-rich phases that coexist with the dilute, macromolecule-deficient phase. In cells, condensates comprise hundreds of different macromolecular and small molecule solutes. Do all components contribute equally or very differently to the driving forces for phase separation? Currently, we lack a coherent formalism to answer this question, a gap we remedy in this work through the introduction of a formalism we term energy dominance analysis. This approach rests on model-free analysis of shapes of the dilute arms of phase boundaries, slopes of tie lines, and changes to dilute phase concentrations in response to perturbations of concentrations of different solutes. We present the formalism that underlies dominance analysis, and establish its accuracy and flexibility by deploying it to analyse phase spaces probed in silico, in vitro , and in cellulo .
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6
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Ray S, Buell AK. Emerging experimental methods to study the thermodynamics of biomolecular condensate formation. J Chem Phys 2024; 160:091001. [PMID: 38445729 DOI: 10.1063/5.0190160] [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: 12/04/2023] [Accepted: 02/15/2024] [Indexed: 03/07/2024] Open
Abstract
The formation of biomolecular condensates in vivo is increasingly recognized to underlie a multitude of crucial cellular functions. Furthermore, the evolution of highly dynamic protein condensates into progressively less reversible assemblies is thought to be involved in a variety of disorders, from cancer over neurodegeneration to rare genetic disorders. There is an increasing need for efficient experimental methods to characterize the thermodynamics of condensate formation and that can be used in screening campaigns to identify and rationally design condensate modifying compounds. Theoretical advances in the field are also identifying the key parameters that need to be measured in order to obtain a comprehensive understanding of the underlying interactions and driving forces. Here, we review recent progress in the development of efficient and quantitative experimental methods to study the driving forces behind and the temporal evolution of biomolecular condensates.
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Affiliation(s)
- Soumik Ray
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Alexander K Buell
- Department of Biotechnology and Biomedicine, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
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7
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Bahramian A. Unlocking the Secrets of Liquid-Liquid Interfaces and Phase Equilibria: Exploring the Interplay of Critical Composition, Interfacial Tension, and Mutual Solubility. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:4684-4701. [PMID: 38381860 DOI: 10.1021/acs.langmuir.3c03344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
This study reveals pivotal insight into liquid-liquid interfaces by demonstrating that the interface composition mirrors that at the critical point. This revelation leads to the formulation of a novel liquid-liquid distribution law and thermodynamic inequality, establishing a direct connection between mutual solubility values and critical compositions. While particularly accurate for regular solutions, the findings exhibit substantial reliability in nonregular systems, supported by experimental data on binary and ternary mixtures. Importantly, the study illustrates that, with known critical compositions, interfacial tension data alone are sufficient for calculating mutual solubilities, providing a practical alternative for assessing molecular solubility. The paper further showcases the versatility of the simple bottle-testing (cloud-testing) method, effectively serving as both a tensiometer and a mutual-solubility meter. This method utilizes established critical composition data to predict the compositions and interfacial tension of coexisting phases concurrently, offering a cost-effective alternative to complex analytical techniques. As a notable outcome, given critical compositions, basic laboratory equipment such as a beaker and a syringe can equivalently function as both a tensiometer and a mutual solubility detector (e.g., GC). The paper also discusses the application of this method in understanding the liquid-liquid phase behavior in biological systems, exemplified by biomolecular condensates or Lewy bodies.
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Affiliation(s)
- Alireza Bahramian
- School of Chemical Engineering, Faculty of Engineering, University of Tehran, Tehran 14174-66191, Iran
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8
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Dolgin E. Fresh tools for watching the 'lava lamps' of living cells. Nature 2024; 626:1152-1154. [PMID: 38413751 DOI: 10.1038/d41586-024-00547-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/29/2024]
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9
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Garg A, González-Foutel NS, Gielnik MB, Kjaergaard M. Design of functional intrinsically disordered proteins. Protein Eng Des Sel 2024; 37:gzae004. [PMID: 38431892 DOI: 10.1093/protein/gzae004] [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: 10/02/2023] [Revised: 12/22/2023] [Indexed: 03/05/2024] Open
Abstract
Many proteins do not fold into a fixed three-dimensional structure, but rather function in a highly disordered state. These intrinsically disordered proteins pose a unique challenge to protein engineering and design: How can proteins be designed de novo if not by tailoring their structure? Here, we will review the nascent field of design of intrinsically disordered proteins with focus on applications in biotechnology and medicine. The design goals should not necessarily be the same as for de novo design of folded proteins as disordered proteins have unique functional strengths and limitations. We focus on functions where intrinsically disordered proteins are uniquely suited including disordered linkers, desiccation chaperones, sensors of the chemical environment, delivery of pharmaceuticals, and constituents of biomolecular condensates. Design of functional intrinsically disordered proteins relies on a combination of computational tools and heuristics gleaned from sequence-function studies. There are few cases where intrinsically disordered proteins have made it into industrial applications. However, we argue that disordered proteins can perform many roles currently performed by organic polymers, and that these proteins might be more designable due to their modularity.
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Affiliation(s)
- Ankush Garg
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| | | | - Maciej B Gielnik
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| | - Magnus Kjaergaard
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus, Denmark
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10
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Herling TW, Invernizzi G, Ausserwöger H, Bjelke JR, Egebjerg T, Lund S, Lorenzen N, Knowles TPJ. Nonspecificity fingerprints for clinical-stage antibodies in solution. Proc Natl Acad Sci U S A 2023; 120:e2306700120. [PMID: 38109540 PMCID: PMC10756282 DOI: 10.1073/pnas.2306700120] [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: 04/28/2023] [Accepted: 11/06/2023] [Indexed: 12/20/2023] Open
Abstract
Monoclonal antibodies (mAbs) have successfully been developed for the treatment of a wide range of diseases. The clinical success of mAbs does not solely rely on optimal potency and safety but also require good biophysical properties to ensure a high developability potential. In particular, nonspecific interactions are a key developability parameter to monitor during discovery and development. Despite an increased focus on the detection of nonspecific interactions, their underlying physicochemical origins remain poorly understood. Here, we employ solution-based microfluidic technologies to characterize a set of clinical-stage mAbs and their interactions with commonly used nonspecificity ligands to generate nonspecificity fingerprints, providing quantitative data on the underlying physical chemistry. Furthermore, the solution-based analysis enables us to measure binding affinities directly, and we evaluate the contribution of avidity in nonspecific binding by mAbs. We find that avidity can increase the apparent affinity by two orders of magnitude. Notably, we find that a subset of these highly developed mAbs show nonspecific electrostatic interactions, even at physiological pH and ionic strength, and that they can form microscale particles with charge-complementary polymers. The group of mAb constructs flagged here for nonspecificity are among the worst performers in independent reports of surface and column-based screens. The solution measurements improve on the state-of-the-art by providing a stand-alone result for individual mAbs without the need to benchmark against cohort data. Based on our findings, we propose a quantitative solution-based nonspecificity score, which can be integrated in the development workflow for biological therapeutics and more widely in protein engineering.
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Affiliation(s)
- Therese W. Herling
- Yusuf Hamied Department of Chemistry, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | | | - Hannes Ausserwöger
- Yusuf Hamied Department of Chemistry, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Jais Rose Bjelke
- Global Research Technologies, Novo Nordisk A/S, Måløv2760, Denmark
| | - Thomas Egebjerg
- Global Research Technologies, Novo Nordisk A/S, Måløv2760, Denmark
| | - Søren Lund
- Global Research Technologies, Novo Nordisk A/S, Måløv2760, Denmark
| | - Nikolai Lorenzen
- Global Research Technologies, Novo Nordisk A/S, Måløv2760, Denmark
| | - Tuomas P. J. Knowles
- Yusuf Hamied Department of Chemistry, University of Cambridge, CambridgeCB2 1EW, United Kingdom
- Department of Physics, University of Cambridge, CambridgeCB3 0HE, United Kingdom
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11
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Kim SC, Mitchell SJ, Qamar S, Whitcomb DJ, Ruepp MD, St George-Hyslop P, Cho K. Mimicking hypomethylation of FUS requires liquid-liquid phase separation to induce synaptic dysfunctions. Acta Neuropathol Commun 2023; 11:199. [PMID: 38105257 PMCID: PMC10726623 DOI: 10.1186/s40478-023-01703-w] [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: 10/23/2023] [Accepted: 11/29/2023] [Indexed: 12/19/2023] Open
Abstract
The hypomethylation of fused in sarcoma (FUS) in frontotemporal lobar degeneration promotes the formation of irreversible condensates of FUS. However, the mechanisms by which these hypomethylated FUS condensates cause neuronal dysfunction are unknown. Here we report that expression of FUS constructs mimicking hypomethylated FUS causes aberrant dendritic FUS condensates in CA1 neurons. These hypomethylated FUS condensates exhibit spontaneous, and activity induced movement within the dendrite. They impair excitatory synaptic transmission, postsynaptic density-95 expression, and dendritic spine plasticity. These neurophysiological defects are dependent upon both the dendritic localisation of the condensates, and their ability to undergo liquid-liquid phase separation. These results indicate that the irreversible liquid-liquid phase separation is a key component of hypomethylated FUS pathophysiology in sporadic FTLD, and this can cause synapse dysfunction in sporadic FTLD.
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Affiliation(s)
- Seung Chan Kim
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, UK-Dementia Research Institute, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, SE5 9NU, UK
| | - Scott J Mitchell
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, UK-Dementia Research Institute, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, SE5 9NU, UK
| | - Seema Qamar
- Department of Clinical Neurosciences, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 0XY, UK
| | | | - Marc-David Ruepp
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, UK-Dementia Research Institute, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, SE5 9NU, UK
| | - Peter St George-Hyslop
- Department of Clinical Neurosciences, Cambridge Institute for Medical Research, University of Cambridge, Cambridge, CB2 0XY, UK
- Department of Medicine (Division of Neurology), University Health Network and Tanz Centre for Research In Neurodegenerative Diseases, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, M5S 3H2, Canada
- Taub Institute For Research On Alzheimer's Disease and the Aging Brain, Department of Neurology, Columbia University Irving Medical Center, 630 West 168 Street, New York, NY, 10032, USA
| | - Kwangwook Cho
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, UK-Dementia Research Institute, Maurice Wohl Clinical Neuroscience Institute, King's College London, London, SE5 9NU, UK.
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12
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Sahin C, Leppert A, Landreh M. Advances in mass spectrometry to unravel the structure and function of protein condensates. Nat Protoc 2023; 18:3653-3661. [PMID: 37907762 DOI: 10.1038/s41596-023-00900-0] [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: 04/18/2023] [Accepted: 08/09/2023] [Indexed: 11/02/2023]
Abstract
Membrane-less organelles assemble through liquid-liquid phase separation (LLPS) of partially disordered proteins into highly specialized microenvironments. Currently, it is challenging to obtain a clear understanding of the relationship between the structure and function of phase-separated protein assemblies, owing to their size, dynamics and heterogeneity. In this Perspective, we discuss recent advances in mass spectrometry (MS) that offer several promising approaches for the study of protein LLPS. We survey MS tools that have provided valuable insights into other insoluble protein systems, such as amyloids, and describe how they can also be applied to study proteins that undergo LLPS. On the basis of these recent advances, we propose to integrate MS into the experimental workflow for LLPS studies. We identify specific challenges and future opportunities for the analysis of protein condensate structure and function by MS.
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Affiliation(s)
- Cagla Sahin
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet-Biomedicum, Solna, Sweden.
- Structural Biology and NMR laboratory and the Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
| | - Axel Leppert
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet-Biomedicum, Solna, Sweden
| | - Michael Landreh
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet-Biomedicum, Solna, Sweden.
- Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden.
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13
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Lin Z, Beneyton T, Baret JC, Martin N. Coacervate Droplets for Synthetic Cells. SMALL METHODS 2023; 7:e2300496. [PMID: 37462244 DOI: 10.1002/smtd.202300496] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 06/15/2023] [Indexed: 12/24/2023]
Abstract
The design and construction of synthetic cells - human-made microcompartments that mimic features of living cells - have experienced a real boom in the past decade. While many efforts have been geared toward assembling membrane-bounded compartments, coacervate droplets produced by liquid-liquid phase separation have emerged as an alternative membrane-free compartmentalization paradigm. Here, the dual role of coacervate droplets in synthetic cell research is discussed: encapsulated within membrane-enclosed compartments, coacervates act as surrogates of membraneless organelles ubiquitously found in living cells; alternatively, they can be viewed as crowded cytosol-like chassis for constructing integrated synthetic cells. After introducing key concepts of coacervation and illustrating the chemical diversity of coacervate systems, their physicochemical properties and resulting bioinspired functions are emphasized. Moving from suspensions of free floating coacervates, the two nascent roles of these droplets in synthetic cell research are highlighted: organelle-like modules and cytosol-like templates. Building the discussion on recent studies from the literature, the potential of coacervate droplets to assemble integrated synthetic cells capable of multiple life-inspired functions is showcased. Future challenges that are still to be tackled in the field are finally discussed.
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Affiliation(s)
- Zi Lin
- Université de Bordeaux, CNRS, Centre de Recherche Paul Pascal, UMR5031, 115 avenue du Dr. Schweitzer, 33600, Pessac, France
| | - Thomas Beneyton
- Université de Bordeaux, CNRS, Centre de Recherche Paul Pascal, UMR5031, 115 avenue du Dr. Schweitzer, 33600, Pessac, France
| | - Jean-Christophe Baret
- Université de Bordeaux, CNRS, Centre de Recherche Paul Pascal, UMR5031, 115 avenue du Dr. Schweitzer, 33600, Pessac, France
| | - Nicolas Martin
- Université de Bordeaux, CNRS, Centre de Recherche Paul Pascal, UMR5031, 115 avenue du Dr. Schweitzer, 33600, Pessac, France
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14
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Fedorov D, Roas-Escalona N, Tolmachev D, Harmat AL, Scacchi A, Sammalkorpi M, Aranko AS, Linder MB. Triblock Proteins with Weakly Dimerizing Terminal Blocks and an Intrinsically Disordered Region for Rational Design of Condensate Properties. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2306817. [PMID: 37964343 DOI: 10.1002/smll.202306817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/20/2023] [Indexed: 11/16/2023]
Abstract
Condensates are molecular assemblies that are formed through liquid-liquid phase separation and play important roles in many biological processes. The rational design of condensate formation and their properties is central to applications, such as biosynthetic materials, synthetic biology, and for understanding cell biology. Protein engineering is used to make a triblock structure with varying terminal blocks of folded proteins on both sides of an intrinsically disordered mid-region. Dissociation constants are determined in the range of micromolar to millimolar for a set of proteins suitable for use as terminal blocks. Varying the weak dimerization of terminal blocks leads to an adjustable tendency for condensate formation while keeping the intrinsically disordered region constant. The dissociation constants of the terminal domains correlate directly with the tendency to undergo liquid-liquid phase separation. Differences in physical properties, such as diffusion rate are not directly correlated with the strength of dimerization but can be understood from the properties and interplay of the constituent blocks. The work demonstrates the importance of weak interactions in condensate formation and shows a principle for protein design that will help in fabricating functional condensates in a predictable and rational way.
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Affiliation(s)
- Dmitrii Fedorov
- Department of Bioproducts and Biosystems, Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
- Center of Excellence in Life-Inspired Hybrid Materials (LIBER), Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
| | - Nelmary Roas-Escalona
- Department of Bioproducts and Biosystems, Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
- Center of Excellence in Life-Inspired Hybrid Materials (LIBER), Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
| | - Dmitry Tolmachev
- Center of Excellence in Life-Inspired Hybrid Materials (LIBER), Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
- Department of Chemistry and Materials Science, Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
| | - Adam L Harmat
- Center of Excellence in Life-Inspired Hybrid Materials (LIBER), Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
- Department of Chemistry and Materials Science, Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
| | - Alberto Scacchi
- Center of Excellence in Life-Inspired Hybrid Materials (LIBER), Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
- Department of Chemistry and Materials Science, Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
- Department of Applied Physics, Aalto University, P.O. Box 11000, Aalto, FI-00076, Finland
| | - Maria Sammalkorpi
- Department of Bioproducts and Biosystems, Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
- Center of Excellence in Life-Inspired Hybrid Materials (LIBER), Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
- Department of Chemistry and Materials Science, Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
| | - A Sesilja Aranko
- Department of Bioproducts and Biosystems, Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
- Center of Excellence in Life-Inspired Hybrid Materials (LIBER), Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
| | - Markus B Linder
- Department of Bioproducts and Biosystems, Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
- Center of Excellence in Life-Inspired Hybrid Materials (LIBER), Aalto University, P.O. Box 16100, Aalto, FI-00076, Finland
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15
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Sneideris T, Erkamp NA, Ausserwöger H, Saar KL, Welsh TJ, Qian D, Katsuya-Gaviria K, Johncock MLLY, Krainer G, Borodavka A, Knowles TPJ. Targeting nucleic acid phase transitions as a mechanism of action for antimicrobial peptides. Nat Commun 2023; 14:7170. [PMID: 37935659 PMCID: PMC10630377 DOI: 10.1038/s41467-023-42374-4] [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: 01/18/2023] [Accepted: 10/10/2023] [Indexed: 11/09/2023] Open
Abstract
Antimicrobial peptides (AMPs), which combat bacterial infections by disrupting the bacterial cell membrane or interacting with intracellular targets, are naturally produced by a number of different organisms, and are increasingly also explored as therapeutics. However, the mechanisms by which AMPs act on intracellular targets are not well understood. Using machine learning-based sequence analysis, we identified a significant number of AMPs that have a strong tendency to form liquid-like condensates in the presence of nucleic acids through phase separation. We demonstrate that this phase separation propensity is linked to the effectiveness of the AMPs in inhibiting transcription and translation in vitro, as well as their ability to compact nucleic acids and form clusters with bacterial nucleic acids in bacterial cells. These results suggest that the AMP-driven compaction of nucleic acids and modulation of their phase transitions constitute a previously unrecognised mechanism by which AMPs exert their antibacterial effects. The development of antimicrobials that target nucleic acid phase transitions may become an attractive route to finding effective and long-lasting antibiotics.
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Affiliation(s)
- Tomas Sneideris
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK
| | - Nadia A Erkamp
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK
| | - Hannes Ausserwöger
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK
| | - Kadi L Saar
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK
| | - Timothy J Welsh
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK
| | - Daoyuan Qian
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK
| | - Kai Katsuya-Gaviria
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, UK
| | - Margaret L L Y Johncock
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK
| | - Georg Krainer
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK
| | - Alexander Borodavka
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, UK.
| | - Tuomas P J Knowles
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK.
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Ave, Cambridge, UK.
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16
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Borodavka A, Acker J. Seeing Biomolecular Condensates Through the Lens of Viruses. Annu Rev Virol 2023; 10:163-182. [PMID: 37040799 DOI: 10.1146/annurev-virology-111821-103226] [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: 04/13/2023]
Abstract
Phase separation of viral biopolymers is a key factor in the formation of cytoplasmic viral inclusions, known as sites of virus replication and assembly. This review describes the mechanisms and factors that affect phase separation in viral replication and identifies potential areas for future research. Drawing inspiration from studies on cellular RNA-rich condensates, we compare the hierarchical coassembly of ribosomal RNAs and proteins in the nucleolus to the coordinated coassembly of viral RNAs and proteins taking place within viral factories in viruses containing segmented RNA genomes. We highlight the common characteristics of biomolecular condensates in viral replication and how this new understanding is reshaping our views of virus assembly mechanisms. Such studies have the potential to uncover unexplored antiviral strategies targeting these phase-separated states.
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Affiliation(s)
- Alexander Borodavka
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom;
| | - Julia Acker
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom;
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17
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Saar KL, Qian D, Good LL, Morgunov AS, Collepardo-Guevara R, Best RB, Knowles TPJ. Theoretical and Data-Driven Approaches for Biomolecular Condensates. Chem Rev 2023; 123:8988-9009. [PMID: 37171907 PMCID: PMC10375482 DOI: 10.1021/acs.chemrev.2c00586] [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: 08/23/2022] [Indexed: 05/14/2023]
Abstract
Biomolecular condensation processes are increasingly recognized as a fundamental mechanism that living cells use to organize biomolecules in time and space. These processes can lead to the formation of membraneless organelles that enable cells to perform distinct biochemical processes in controlled local environments, thereby supplying them with an additional degree of spatial control relative to that achieved by membrane-bound organelles. This fundamental importance of biomolecular condensation has motivated a quest to discover and understand the molecular mechanisms and determinants that drive and control this process. Within this molecular viewpoint, computational methods can provide a unique angle to studying biomolecular condensation processes by contributing the resolution and scale that are challenging to reach with experimental techniques alone. In this Review, we focus on three types of dry-lab approaches: theoretical methods, physics-driven simulations and data-driven machine learning methods. We review recent progress in using these tools for probing biomolecular condensation across all three fields and outline the key advantages and limitations of each of the approaches. We further discuss some of the key outstanding challenges that we foresee the community addressing next in order to develop a more complete picture of the molecular driving forces behind biomolecular condensation processes and their biological roles in health and disease.
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Affiliation(s)
- Kadi L. Saar
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Cambridge CB2 1EW, United Kingdom
- Transition
Bio Ltd., Cambridge, United Kingdom
| | - Daoyuan Qian
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Lydia L. Good
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Cambridge CB2 1EW, United Kingdom
- Laboratory
of Chemical Physics, National Institute of Diabetes and Digestive
and Kidney Diseases, National Institutes
of Health, Bethesda, Maryland 20892, United States
| | - Alexey S. Morgunov
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Rosana Collepardo-Guevara
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Cambridge CB2 1EW, United Kingdom
- Department
of Genetics, University of Cambridge, Cambridge CB2 3EH, United Kingdom
| | - Robert B. Best
- Laboratory
of Chemical Physics, National Institute of Diabetes and Digestive
and Kidney Diseases, National Institutes
of Health, Bethesda, Maryland 20892, United States
| | - Tuomas P. J. Knowles
- Yusuf
Hamied Department of Chemistry, University
of Cambridge, Cambridge CB2 1EW, United Kingdom
- Cavendish
Laboratory, Department of Physics, University
of Cambridge, Cambridge CB3 0HE, United Kingdom
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18
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Malhotra I, Potoyan DA. Re-entrant transitions of locally stiff RNA chains in the presence of polycations leads to gelated architectures. SOFT MATTER 2023. [PMID: 37449795 PMCID: PMC10369498 DOI: 10.1039/d3sm00320e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
The liquid-liquid phase separation of protein and nucleic acid mixtures drives the formation of numerous membraneless compartments in cells. Temperature variation is commonly used for mapping condensate phase diagrams, which often display unique upper critical temperatures. Recent report on peptide-RNA mixtures has shown the existence of lower and upper critical solution temperatures, highlighting the importance of temperature-dependent solvent and ion-mediated forces. In the present work, we employ residue-level coarse-grained models of RNA and polycation peptide chains for simulating temperature-induced re-entrant transitions and shedding light on the role played by mobile ions, temperature-dependent dielectric permittivity, and local chain stiffness. We show that differences in bending rigidity can significantly modulate condensate topology leading to the formation of gelated or fibril like architectures. The study also finds that temperature dependence of water permittivity is generally sufficient for recapitulating experimentally observed closed loop and LCST phase diagrams of highly charged protein-RNA mixtures. However, we find that similar-looking closed-loop phase diagrams can correspond to vastly different condensate topologies.
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Affiliation(s)
- Isha Malhotra
- Department of Chemistry, Iowa State University, Ames, Iowa 50014, USA.
| | - Davit A Potoyan
- Department of Chemistry, Iowa State University, Ames, Iowa 50014, USA.
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19
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Ausserwöger H, Krainer G, Welsh TJ, Thorsteinson N, de Csilléry E, Sneideris T, Schneider MM, Egebjerg T, Invernizzi G, Herling TW, Lorenzen N, Knowles TPJ. Surface patches induce nonspecific binding and phase separation of antibodies. Proc Natl Acad Sci U S A 2023; 120:e2210332120. [PMID: 37011217 PMCID: PMC10104583 DOI: 10.1073/pnas.2210332120] [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: 06/21/2022] [Accepted: 02/06/2023] [Indexed: 04/05/2023] Open
Abstract
Nonspecific interactions are a key challenge in the successful development of therapeutic antibodies. The tendency for nonspecific binding of antibodies is often difficult to reduce by rational design, and instead, it is necessary to rely on comprehensive screening campaigns. To address this issue, we performed a systematic analysis of the impact of surface patch properties on antibody nonspecificity using a designer antibody library as a model system and single-stranded DNA as a nonspecificity ligand. Using an in-solution microfluidic approach, we find that the antibodies tested bind to single-stranded DNA with affinities as high as KD = 1 µM. We show that DNA binding is driven primarily by a hydrophobic patch in the complementarity-determining regions. By quantifying the surface patches across the library, the nonspecific binding affinity is shown to correlate with a trade-off between the hydrophobic and total charged patch areas. Moreover, we show that a change in formulation conditions at low ionic strengths leads to DNA-induced antibody phase separation as a manifestation of nonspecific binding at low micromolar antibody concentrations. We highlight that phase separation is driven by a cooperative electrostatic network assembly mechanism of antibodies with DNA, which correlates with a balance between positive and negative charged patches. Importantly, our study demonstrates that both nonspecific binding and phase separation are controlled by the size of the surface patches. Taken together, these findings highlight the importance of surface patches and their role in conferring antibody nonspecificity and its macroscopic manifestation in phase separation.
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Affiliation(s)
- Hannes Ausserwöger
- Yusuf Hamied Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Georg Krainer
- Yusuf Hamied Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Timothy J. Welsh
- Yusuf Hamied Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Nels Thorsteinson
- Research and Development, Chemical Computing Group, Montreal, QuebecH3A 2R7, Canada
| | - Ella de Csilléry
- Yusuf Hamied Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Tomas Sneideris
- Yusuf Hamied Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Matthias M. Schneider
- Yusuf Hamied Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Thomas Egebjerg
- Global Research Technologies, Novo Nordisk A/S2760Måløv, Denmark
| | | | - Therese W. Herling
- Yusuf Hamied Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, CambridgeCB2 1EW, United Kingdom
| | - Nikolai Lorenzen
- Global Research Technologies, Novo Nordisk A/S2760Måløv, Denmark
| | - Tuomas P. J. Knowles
- Yusuf Hamied Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, CambridgeCB2 1EW, United Kingdom
- Department of Physics, Cavendish Laboratory, University of Cambridge, CambridgeCB3 0HE, United Kingdom
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20
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Macromolecular Crowding Is Surprisingly Unable to Deform the Structure of a Model Biomolecular Condensate. BIOLOGY 2023; 12:biology12020181. [PMID: 36829460 PMCID: PMC9952705 DOI: 10.3390/biology12020181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/27/2023]
Abstract
The crowded interior of a living cell makes performing experiments on simpler in vitro systems attractive. Although these reveal interesting phenomena, their biological relevance can be questionable. A topical example is the phase separation of intrinsically disordered proteins into biomolecular condensates, which is proposed to underlie the membrane-less compartmentalization of many cellular functions. How a cell reliably controls biochemical reactions in compartments open to the compositionally-varying cytoplasm is an important question for understanding cellular homeostasis. Computer simulations are often used to study the phase behavior of model biomolecular condensates, but the number of relevant parameters increases as the number of protein components increases. It is unfeasible to exhaustively simulate such models for all parameter combinations, although interesting phenomena are almost certainly hidden in their high-dimensional parameter space. Here, we have studied the phase behavior of a model biomolecular condensate in the presence of a polymeric crowding agent. We used a novel compute framework to execute dozens of simultaneous simulations spanning the protein/crowder concentration space. We then combined the results into a graphical representation for human interpretation, which provided an efficient way to search the model's high-dimensional parameter space. We found that steric repulsion from the crowder drives a near-critical system across the phase boundary, but the molecular arrangement within the resulting biomolecular condensate is rather insensitive to the crowder concentration and molecular weight. We propose that a cell may use the local cytoplasmic concentration to assist the formation of biomolecular condensates, while relying on the dense phase to reliably provide a stable, structured, fluid milieu for cellular biochemistry despite being open to its changing environment.
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