1
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Zhou HX, Kota D, Qin S, Prasad R. Fundamental Aspects of Phase-Separated Biomolecular Condensates. Chem Rev 2024; 124:8550-8595. [PMID: 38885177 PMCID: PMC11260227 DOI: 10.1021/acs.chemrev.4c00138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
Biomolecular condensates, formed through phase separation, are upending our understanding in much of molecular, cell, and developmental biology. There is an urgent need to elucidate the physicochemical foundations of the behaviors and properties of biomolecular condensates. Here we aim to fill this need by writing a comprehensive, critical, and accessible review on the fundamental aspects of phase-separated biomolecular condensates. We introduce the relevant theoretical background, present the theoretical basis for the computation and experimental measurement of condensate properties, and give mechanistic interpretations of condensate behaviors and properties in terms of interactions at the molecular and residue levels.
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Affiliation(s)
- Huan-Xiang Zhou
- Department of Chemistry, University of Illinois Chicago, Chicago, Illinois 60607, USA
- Department of Physics, University of Illinois Chicago, Chicago, Illinois 60607, USA
| | - Divya Kota
- Department of Chemistry, University of Illinois Chicago, Chicago, Illinois 60607, USA
| | - Sanbo Qin
- Department of Chemistry, University of Illinois Chicago, Chicago, Illinois 60607, USA
| | - Ramesh Prasad
- Department of Chemistry, University of Illinois Chicago, Chicago, Illinois 60607, USA
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2
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König B, Pezzotti S, Ramos S, Schwaab G, Havenith M. Real-time measure of solvation free energy changes upon liquid-liquid phase separation of α-elastin. Biophys J 2024; 123:1367-1375. [PMID: 37515326 PMCID: PMC11163292 DOI: 10.1016/j.bpj.2023.07.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 06/16/2023] [Accepted: 07/26/2023] [Indexed: 07/30/2023] Open
Abstract
Biological condensates are known to retain a large fraction of water to remain in a liquid and reversible state. Local solvation contributions from water hydrating hydrophilic and hydrophobic protein surfaces were proposed to play a prominent role for the formation of condensates through liquid-liquid phase separation (LLPS). However, although the total free energy is accessible by calorimetry, the partial solvent contributions to the free energy changes upon LLPS remained experimentally inaccessible so far. Here, we show that the recently developed THz calorimetry approach allows to quantify local hydration enthalpy and entropy changes upon LLPS of α-elastin in real time, directly from experimental THz spectroscopy data. We find that hydrophobic solvation dominates the entropic solvation term, whereas hydrophilic solvation mainly contributes to the enthalpy. Both terms are in the order of hundreds of kJ/mol, which is more than one order of magnitude larger than the total free energy changes at play during LLPS. However, since we show that entropy/enthalpy mostly compensates, a small entropy/enthalpy imbalance is sufficient to tune LLPS. Theoretically, a balance was proposed before. Here we present experimental evidence based on our spectroscopic approach. We finally show that LLPS can be steered by inducing small changes of solvation entropy/enthalpy compensation via concentration or temperature in α-elastin.
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Affiliation(s)
- Benedikt König
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, Bochum, Germany
| | - Simone Pezzotti
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, Bochum, Germany
| | - Sashary Ramos
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, Bochum, Germany
| | - Gerhard Schwaab
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, Bochum, Germany
| | - Martina Havenith
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, Bochum, Germany.
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3
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Li S, Zhang Y, Chen J. Backbone interactions and secondary structures in phase separation of disordered proteins. Biochem Soc Trans 2024; 52:319-329. [PMID: 38348795 DOI: 10.1042/bst20230618] [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: 11/29/2023] [Revised: 01/23/2024] [Accepted: 01/25/2024] [Indexed: 02/29/2024]
Abstract
Intrinsically disordered proteins (IDPs) are one of the major drivers behind the formation and characteristics of biomolecular condensates. Due to their inherent flexibility, the backbones of IDPs are significantly exposed, rendering them highly influential and susceptible to biomolecular phase separation. In densely packed condensates, exposed backbones have a heightened capacity to interact with neighboring protein chains, which might lead to strong coupling between the secondary structures and phase separation and further modulate the subsequent transitions of the condensates, such as aging and fibrillization. In this mini-review, we provide an overview of backbone-mediated interactions and secondary structures within biomolecular condensates to underscore the importance of protein backbones in phase separation. We further focus on recent advances in experimental techniques and molecular dynamics simulation methods for probing and exploring the roles of backbone interactions and secondary structures in biomolecular phase separation involving IDPs.
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Affiliation(s)
- Shanlong Li
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003, U.S.A
| | - Yumeng Zhang
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003, U.S.A
| | - Jianhan Chen
- Department of Chemistry, University of Massachusetts, Amherst, MA 01003, U.S.A
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4
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Papadakis CM, Niebuur BJ, Schulte A. Thermoresponsive Polymers under Pressure with a Focus on Poly( N-isopropylacrylamide) (PNIPAM). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:1-20. [PMID: 38149782 DOI: 10.1021/acs.langmuir.3c02398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2023]
Abstract
Pressure is a key variable in the phase behavior of responsive polymers, both for applications and from a fundamental point of view. In this feature article, we review recent developments, particularly applications of neutron techniques such as small-angle neutron scattering (SANS) and quasi-elastic neutron scattering (QENS), across the temperature-pressure phase diagram. These are complemented by kinetic SANS experiments following pressure jumps. In the prototype system poly(N-isopropylacrylamide) (PNIPAM), QENS revealed the pressure-dependent characteristics of hydration water around the lower critical solution temperature transition. The size, water content, and inner structure of the mesoglobules formed in the two-phase region depend strongly on pressure, as shown by SANS. Beside these changes at the phase transition, the mesoglobule formation at low pressure is determined by kinetic factors, namely the formation of a polymer-rich, rigid shell, which hampers further growth by coalescence. At high pressure, in contrast, the growth proceeds by diffusion-limited coalescence without any kinetic hindrance. The disintegration of the mesoglobules evolves either via chain release from their surface or via swelling, depending on the osmotic pressure of the water. Moreover, we report on the profound influence of pressure on the cononsolvency effect. In the temperature-pressure frame, the one-phase region is hugely expanded upon the addition of the cosolvent methanol. SANS experiments unveil the enthalpic and entropic contributions to the effective Flory-Huggins interaction parameter between the segments and the solvent mixture. QENS experiments demonstrate an increase in polymer associated water with pressure, whereas methanol is released. Correspondingly, the solvent phase becomes enriched in methanol, providing a mechanism for the breakdown of cononsolvency at a high pressure. Finally, we outline future opportunities for high-pressure studies of thermoresponsive polymers, with a focus on neutron methods.
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Affiliation(s)
- Christine M Papadakis
- TUM School of Natural Sciences, Physics Department, Soft Matter Physics Group, Technical University of Munich, James-Franck-Str. 1, 85748 Garching, Germany
| | - Bart-Jan Niebuur
- TUM School of Natural Sciences, Physics Department, Soft Matter Physics Group, Technical University of Munich, James-Franck-Str. 1, 85748 Garching, Germany
| | - Alfons Schulte
- Department of Physics and College of Optics and Photonics, University of Central Florida, 4111 Libra Drive, Orlando, Florida 32816-2385, United States
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5
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Peters J, Oliva R, Caliò A, Oger P, Winter R. Effects of Crowding and Cosolutes on Biomolecular Function at Extreme Environmental Conditions. Chem Rev 2023; 123:13441-13488. [PMID: 37943516 DOI: 10.1021/acs.chemrev.3c00432] [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: 11/10/2023]
Abstract
The extent of the effect of cellular crowding and cosolutes on the functioning of proteins and cells is manifold and includes the stabilization of the biomolecular systems, the excluded volume effect, and the modulation of molecular dynamics. Simultaneously, it is becoming increasingly clear how important it is to take the environment into account if we are to shed light on biological function under various external conditions. Many biosystems thrive under extreme conditions, including the deep sea and subseafloor crust, and can take advantage of some of the effects of crowding. These relationships have been studied in recent years using various biophysical techniques, including neutron and X-ray scattering, calorimetry, FTIR, UV-vis and fluorescence spectroscopies. Combining knowledge of the structure and conformational dynamics of biomolecules under extreme conditions, such as temperature, high hydrostatic pressure, and high salinity, we highlight the importance of considering all results in the context of the environment. Here we discuss crowding and cosolute effects on proteins, nucleic acids, membranes, and live cells and explain how it is possible to experimentally separate crowding-induced effects from other influences. Such findings will contribute to a better understanding of the homeoviscous adaptation of organisms and the limits of life in general.
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Affiliation(s)
- Judith Peters
- Univ. Grenoble Alpes, CNRS, LiPhy, 140 rue de la physique, 38400 St Martin d'Hères, France
- Institut Laue Langevin, 71 avenue des Martyrs, 38000 Grenoble, France
- Institut Universitaire de France, 75005 Paris, France
| | - Rosario Oliva
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, 80126 Naples, Italy
| | - Antonino Caliò
- European Synchrotron Radiation Facility, 71 avenue des Martyrs, 38000 Grenoble, France
| | - Philippe Oger
- INSA Lyon, Universite Claude Bernard Lyon1, CNRS, UMR5240, 69621 Villeurbanne, France
| | - Roland Winter
- Department of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, Dortmund, Otto-Hahn-Str. 4a, D-44227 Dortmund, Germany
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6
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Patel CK, Rani C, Kumar R, Mukherjee TK. Macromolecular Crowding Promotes Re-entrant Liquid-Liquid Phase Separation of Human Serum Transferrin and Prevents Surface-Induced Fibrillation. Biomacromolecules 2023; 24:3917-3928. [PMID: 37503577 DOI: 10.1021/acs.biomac.3c00550] [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: 07/29/2023]
Abstract
Protein aggregation and inactivation upon surface immobilization are major limiting factors for analytical applications in biotechnology-related fields. Protein immobilization on solid surfaces often requires multi-step surface passivation, which is time-consuming and inefficient. Herein, we have discovered that biomolecular condensates of biologically active human serum transferrin (Tf) can effectively prevent surface-induced fibrillation and preserve the native-like conformation of phase-separated Tf over a period of 30 days. It has been observed that macromolecular crowding promotes homotypic liquid-liquid phase separation (LLPS) of Tf through enthalpically driven multivalent hydrophobic interactions possibly via the involvement of its low-complexity domain (residues 3-20) containing hydrophobic amino acids. The present LLPS of Tf is a rare example of salt-mediated re-entrant phase separation in a broad range of salt concentrations (0-3 M) solely via the involvement of hydrophobic interactions. Notably, no liquid-to-solid-like phase transition has been observed over a period of 30 days, suggesting the intact conformational integrity of phase-separated Tf, as revealed from single droplet Raman, circular dichroism, and Fourier transform infrared spectroscopy measurements. More importantly, we discovered that the phase-separated condensates of Tf completely inhibit the surface-induced fibrillation of Tf, illustrating the protective role of these liquid-like condensates against denaturation and aggregation of biomolecules. The cell mimicking compact aqueous compartments of biomolecular condensates with a substantial amount of interfacial water preserve the structure and functionality of Tf. Our present study highlights an important functional aspect of biologically active protein condensates and may have wide-ranging implications in cell physiology and biotechnological applications.
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Affiliation(s)
- Chinmaya Kumar Patel
- Department of Chemistry, Indian Institute of Technology (IIT) Indore, Simrol, Indore 453552, Madhya Pradesh, India
| | - Chanchal Rani
- Department of Physics, Indian Institute of Technology (IIT) Indore, Simrol, Indore 453552, Madhya Pradesh, India
| | - Rajesh Kumar
- Department of Physics, Indian Institute of Technology (IIT) Indore, Simrol, Indore 453552, Madhya Pradesh, India
| | - Tushar Kanti Mukherjee
- Department of Chemistry, Indian Institute of Technology (IIT) Indore, Simrol, Indore 453552, Madhya Pradesh, India
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7
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Pezzotti S, König B, Ramos S, Schwaab G, Havenith M. Liquid-Liquid Phase Separation? Ask the Water! J Phys Chem Lett 2023; 14:1556-1563. [PMID: 36745512 DOI: 10.1021/acs.jpclett.2c02697] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Water is more than an inert spectator during liquid-liquid phase separation (LLPS), the reversible compartmentalization of protein solutions into a protein-rich and a dilute phase. We show that LLPS is driven by changes in hydration entropy and enthalpy. Tuning LLPS by adjusting experimental parameters, e.g., addition of co-solutes, is a major goal for biological and medical applications. This requires a general model to quantify thermodynamic driving forces. Here, we develop such a model based on the measured amplitudes of characteristic THz-features of two hydration populations: "Cavity-wrap" water hydrating hydrophobic patches is released during LLPS leading to an increase in entropy. "Bound" water hydrating hydrophilic patches is retained since it is enthalpically favorable. We introduce a THz-phase diagram mapping these spectroscopic/thermodynamic changes. This provides not only a precise understanding of hydrophobic and hydrophilic hydration driving forces as a function of temperature and concentration but also a rational means to tune LLPS.
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Affiliation(s)
- Simone Pezzotti
- Department of Physical Chemistry II, Ruhr University Bochum, 44801Bochum, Germany
| | - Benedikt König
- Department of Physical Chemistry II, Ruhr University Bochum, 44801Bochum, Germany
| | - Sashary Ramos
- Department of Physical Chemistry II, Ruhr University Bochum, 44801Bochum, Germany
| | - Gerhard Schwaab
- Department of Physical Chemistry II, Ruhr University Bochum, 44801Bochum, Germany
| | - Martina Havenith
- Department of Physical Chemistry II, Ruhr University Bochum, 44801Bochum, Germany
- Department of Physics, Technische Universität Dortmund, 44227Dortmund, Germany
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8
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Knop JM, Mukherjee S, Jaworek MW, Kriegler S, Manisegaran M, Fetahaj Z, Ostermeier L, Oliva R, Gault S, Cockell CS, Winter R. Life in Multi-Extreme Environments: Brines, Osmotic and Hydrostatic Pressure─A Physicochemical View. Chem Rev 2023; 123:73-104. [PMID: 36260784 DOI: 10.1021/acs.chemrev.2c00491] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Elucidating the details of the formation, stability, interactions, and reactivity of biomolecular systems under extreme environmental conditions, including high salt concentrations in brines and high osmotic and high hydrostatic pressures, is of fundamental biological, astrobiological, and biotechnological importance. Bacteria and archaea are able to survive in the deep ocean or subsurface of Earth, where pressures of up to 1 kbar are reached. The deep subsurface of Mars may host high concentrations of ions in brines, such as perchlorates, but we know little about how these conditions and the resulting osmotic stress conditions would affect the habitability of such environments for cellular life. We discuss the combined effects of osmotic (salts, organic cosolvents) and hydrostatic pressures on the structure, stability, and reactivity of biomolecular systems, including membranes, proteins, and nucleic acids. To this end, a variety of biophysical techniques have been applied, including calorimetry, UV/vis, FTIR and fluorescence spectroscopy, and neutron and X-ray scattering, in conjunction with high pressure techniques. Knowledge of these effects is essential to our understanding of life exposed to such harsh conditions, and of the physical limits of life in general. Finally, we discuss strategies that not only help us understand the adaptive mechanisms of organisms that thrive in such harsh geological settings but could also have important ramifications in biotechnological and pharmaceutical applications.
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Affiliation(s)
- Jim-Marcel Knop
- Department of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, D-44221Dortmund, Germany
| | - Sanjib Mukherjee
- Department of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, D-44221Dortmund, Germany
| | - Michel W Jaworek
- Department of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, D-44221Dortmund, Germany
| | - Simon Kriegler
- Department of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, D-44221Dortmund, Germany
| | - Magiliny Manisegaran
- Department of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, D-44221Dortmund, Germany
| | - Zamira Fetahaj
- Department of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, D-44221Dortmund, Germany
| | - Lena Ostermeier
- Department of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, D-44221Dortmund, Germany
| | - Rosario Oliva
- Department of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, D-44221Dortmund, Germany.,Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, 80126Naples, Italy
| | - Stewart Gault
- UK Centre for Astrobiology, SUPA School of Physics and Astronomy, University of Edinburgh, James Clerk Maxwell Building, Peter Guthrie Tait Road, EH9 3FDEdinburgh, United Kingdom
| | - Charles S Cockell
- UK Centre for Astrobiology, SUPA School of Physics and Astronomy, University of Edinburgh, James Clerk Maxwell Building, Peter Guthrie Tait Road, EH9 3FDEdinburgh, United Kingdom
| | - Roland Winter
- Department of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, D-44221Dortmund, Germany
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9
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Fetahaj Z, Jaworek MW, Oliva R, Winter R. Suppression of Liquid‐Liquid Phase Separation and Aggregation of Antibodies by Modest Pressure Application. Chemistry 2022; 28:e202201658. [PMID: 35759377 PMCID: PMC9544093 DOI: 10.1002/chem.202201658] [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: 05/30/2022] [Indexed: 11/09/2022]
Abstract
The high colloidal stability of antibody (immunoglobulin) solutions is important for pharmaceutical applications. Inert cosolutes, excipients, are generally used in therapeutic protein formulations to minimize physical instabilities, such as liquid–liquid phase separation (LLPS), aggregation and precipitation, which are often encountered during manufacturing and storage. Despite their widespread use, a detailed understanding of how excipients modulate the specific protein‐protein interactions responsible for these instabilities is still lacking. In this work, we demonstrate the high sensitivity to pressure of globulin condensates as a suitable means to suppress LLPS and subsequent aggregation of concentrated antibody solutions. The addition of excipients has only a minor effect. The high pressure sensitivity observed is due to the fact that these flexible Y‐shaped molecules create a considerable amount of void volume in the condensed phase, leading to an overall decrease in the volume of the system upon dissociation of the droplet phase by pressure already at a few tens of to hundred bar. Moreover, we show that immunoglobulin molecules themselves are highly resistant to unfolding under pressure, and can even sustain pressures up to about 6 kbar without conformational changes. This implies that immunoglobulins are resistant to the pressure treatment of foods, such as milk, in high‐pressure food‐processing technologies, thereby preserving their immunological activity.
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Affiliation(s)
- Zamira Fetahaj
- Physical Chemistry I–Biophysical Chemistry Department of Chemistry and Chemical Biology TU Dortmund Otto-Hahn-Strasse 4a 44227 Dortmund Germany
| | - Michel W. Jaworek
- Physical Chemistry I–Biophysical Chemistry Department of Chemistry and Chemical Biology TU Dortmund Otto-Hahn-Strasse 4a 44227 Dortmund Germany
| | - Rosario Oliva
- Physical Chemistry I–Biophysical Chemistry Department of Chemistry and Chemical Biology TU Dortmund Otto-Hahn-Strasse 4a 44227 Dortmund Germany
- Department of Chemical Sciences University of Naples Federico II Via Cintia 4 80126 Naples Italy
| | - Roland Winter
- Physical Chemistry I–Biophysical Chemistry Department of Chemistry and Chemical Biology TU Dortmund Otto-Hahn-Strasse 4a 44227 Dortmund Germany
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10
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Cinar H, Oliva R, Wu H, Zhang M, Chan HS, Winter R. Effects of Cosolvents and Crowding Agents on the Stability and Phase Transition Kinetics of the SynGAP/PSD-95 Condensate Model of Postsynaptic Densities. J Phys Chem B 2022; 126:1734-1741. [PMID: 35171623 DOI: 10.1021/acs.jpcb.2c00794] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The SynGAP/PSD-95 binary protein system serves as a simple mimicry of postsynaptic densities (PSDs), which are protein assemblies based largely on liquid-liquid phase separation (LLPS), that are located underneath the plasma membrane of excitatory synapses. Surprisingly, the LLPS of the SynGAP/PSD-95 system is much more pressure sensitive than typical folded states of proteins or nucleic acids. It was found that phase-separated SynGAP/PSD-95 droplets dissolve into a homogeneous solution at a pressure of tens to hundred bar. Since organisms in the deep sea are exposed to pressures of up to ∼1000 bar, this observation suggests that deep-sea organisms must counteract the high pressure sensitivity of PSDs to avoid neurological impairment. We demonstrate here that the compatible osmolyte trimethylamine-N-oxide (TMAO) as well as macromolecular crowding agents at moderate concentrations can mitigate the deleterious effect of pressure on SynGAP/PSD-95 droplet stability, extending stable LLPS up to almost a kbar level. Moreover, the formation of SynGAP/PSD-95 droplets is a very rapid process that can be switched on and off in seconds. In contrast with the marked effects of the cosolutes on droplet stability, at the cosolutes' respective biologically relevant concentrations, their impact on the phase transformation kinetics is rather small. Only a high TMAO concentration results in a significant kinetic retardation of LLPS. Taken together, these findings offer new biophysical insights into the neurological effects of hydrostatic pressure. In particular, our results indicate how pressure-induced neurological disorders might be alleviated by upregulating certain cosolutes in the cellular milieu.
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Affiliation(s)
- Hasan Cinar
- Physical Chemistry I - Biophysical Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
| | - Rosario Oliva
- Physical Chemistry I - Biophysical Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
| | - Haowei Wu
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong, China
| | - Mingjie Zhang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong, China.,School of Life Sciences, Southern University of Science and Technology, Shenzhen 518055, China
| | - Hue Sun Chan
- Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Roland Winter
- Physical Chemistry I - Biophysical Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
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11
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Sheehan F, Sementa D, Jain A, Kumar M, Tayarani-Najjaran M, Kroiss D, Ulijn RV. Peptide-Based Supramolecular Systems Chemistry. Chem Rev 2021; 121:13869-13914. [PMID: 34519481 DOI: 10.1021/acs.chemrev.1c00089] [Citation(s) in RCA: 138] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Peptide-based supramolecular systems chemistry seeks to mimic the ability of life forms to use conserved sets of building blocks and chemical reactions to achieve a bewildering array of functions. Building on the design principles for short peptide-based nanomaterials with properties, such as self-assembly, recognition, catalysis, and actuation, are increasingly available. Peptide-based supramolecular systems chemistry is starting to address the far greater challenge of systems-level design to access complex functions that emerge when multiple reactions and interactions are coordinated and integrated. We discuss key features relevant to systems-level design, including regulating supramolecular order and disorder, development of active and adaptive systems by considering kinetic and thermodynamic design aspects and combinatorial dynamic covalent and noncovalent interactions. Finally, we discuss how structural and dynamic design concepts, including preorganization and induced fit, are critical to the ability to develop adaptive materials with adaptive and tunable photonic, electronic, and catalytic properties. Finally, we highlight examples where multiple features are combined, resulting in chemical systems and materials that display adaptive properties that cannot be achieved without this level of integration.
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Affiliation(s)
- Fahmeed Sheehan
- Advanced Science Research Center (ASRC) at the Graduate Center City University of New York 85 St. Nicholas Terrace New York, New York 10031, United States.,Department of Chemistry, Hunter College City University of New York 695 Park Avenue, New York, New York 10065, United States.,Ph.D. Program in Chemistry The Graduate Center of the City University of New York 365 fifth Avenue, New York, New York 10016, United States
| | - Deborah Sementa
- Advanced Science Research Center (ASRC) at the Graduate Center City University of New York 85 St. Nicholas Terrace New York, New York 10031, United States
| | - Ankit Jain
- Advanced Science Research Center (ASRC) at the Graduate Center City University of New York 85 St. Nicholas Terrace New York, New York 10031, United States
| | - Mohit Kumar
- Advanced Science Research Center (ASRC) at the Graduate Center City University of New York 85 St. Nicholas Terrace New York, New York 10031, United States.,Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 10-12, Barcelona 08028, Spain
| | - Mona Tayarani-Najjaran
- Advanced Science Research Center (ASRC) at the Graduate Center City University of New York 85 St. Nicholas Terrace New York, New York 10031, United States.,Department of Chemistry, Hunter College City University of New York 695 Park Avenue, New York, New York 10065, United States.,Ph.D. Program in Chemistry The Graduate Center of the City University of New York 365 fifth Avenue, New York, New York 10016, United States
| | - Daniela Kroiss
- Advanced Science Research Center (ASRC) at the Graduate Center City University of New York 85 St. Nicholas Terrace New York, New York 10031, United States.,Department of Chemistry, Hunter College City University of New York 695 Park Avenue, New York, New York 10065, United States.,Ph.D. Program in Biochemistry The Graduate Center of the City University of New York 365 5th Avenue, New York, New York 10016, United States
| | - Rein V Ulijn
- Advanced Science Research Center (ASRC) at the Graduate Center City University of New York 85 St. Nicholas Terrace New York, New York 10031, United States.,Department of Chemistry, Hunter College City University of New York 695 Park Avenue, New York, New York 10065, United States.,Ph.D. Program in Chemistry The Graduate Center of the City University of New York 365 fifth Avenue, New York, New York 10016, United States.,Ph.D. Program in Biochemistry The Graduate Center of the City University of New York 365 5th Avenue, New York, New York 10016, United States
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12
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Li S, Yoshizawa T, Yamazaki R, Fujiwara A, Kameda T, Kitahara R. Pressure and Temperature Phase Diagram for Liquid-Liquid Phase Separation of the RNA-Binding Protein Fused in Sarcoma. J Phys Chem B 2021; 125:6821-6829. [PMID: 34156864 DOI: 10.1021/acs.jpcb.1c01451] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Liquid-liquid phase separation (LLPS) of proteins and nucleic acids to form membraneless cellular compartments is considered to be involved in various biological functions. The RNA-binding protein fused in sarcoma (FUS) undergoes LLPS in vivo and in vitro. Here, we investigated the effects of pressure and temperature on the LLPS of FUS by high-pressure microscopy and high-pressure UV/vis spectroscopy. The phase-separated condensate of FUS was obliterated with increasing pressure but was observed again at a higher pressure. We generated a pressure-temperature phase diagram that describes the phase separation of FUS and provides a general understanding of the thermodynamic properties of self-assembly and phase separation of proteins. FUS has two types of condensed phases, observed at low pressure (LP-LLPS) and high pressure (HP-LLPS). The HP-LLPS state was more condensed and exhibited lower susceptibility to dissolution by 1,6-hexanediol and karyopherin-β2 than the LP-LLPS state. Moreover, molecular dynamic simulations revealed that electrostatic interactions were destabilized, whereas cation-π, π-π, and hydrophobic interactions were stabilized in HP-LLPS. When cation-π, π-π, and hydrophobic interactions were transiently stabilized in the cellular environment, the phase transition to HP-LLPS occurred; this might be correlated to the aberrant enrichment of cytoplasmic ribonucleoprotein granules, leading to amyotrophic lateral sclerosis.
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Affiliation(s)
- Shujie Li
- Graduate School of Life Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan
| | - Takuya Yoshizawa
- College of Life Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan
| | - Ryota Yamazaki
- College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan
| | - Ayano Fujiwara
- Graduate School of Life Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan
| | - Tomoshi Kameda
- Artificial Intelligence Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Koto, Tokyo 135-0064, Japan
| | - Ryo Kitahara
- College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577, Japan
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Wessén J, Pal T, Das S, Lin YH, Chan HS. A Simple Explicit-Solvent Model of Polyampholyte Phase Behaviors and Its Ramifications for Dielectric Effects in Biomolecular Condensates. J Phys Chem B 2021; 125:4337-4358. [PMID: 33890467 DOI: 10.1021/acs.jpcb.1c00954] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Biomolecular condensates such as membraneless organelles, underpinned by liquid-liquid phase separation (LLPS), are important for physiological function, with electrostatics, among other interaction types, being a prominent force in their assembly. Charge interactions of intrinsically disordered proteins (IDPs) and other biomolecules are sensitive to the aqueous dielectric environment. Because the relative permittivity of protein is significantly lower than that of water, the interior of an IDP condensate is expected to be a relatively low-dielectric regime, which aside from its possible functional effects on client molecules should facilitate stronger electrostatic interactions among the scaffold IDPs. To gain insight into this LLPS-induced dielectric heterogeneity, addressing in particular whether a low-dielectric condensed phase entails more favorable LLPS than that posited by assuming IDP electrostatic interactions are uniformly modulated by the higher dielectric constant of the pure solvent, we consider a simplified multiple-chain model of polyampholytes immersed in explicit solvents that are either polarizable or possess a permanent dipole. Notably, simulated phase behaviors of these systems exhibit only minor to moderate differences from those obtained using implicit-solvent models with a uniform relative permittivity equals to that of pure solvent. Buttressed by theoretical treatments developed here using random phase approximation and polymer field-theoretic simulations, these observations indicate a partial compensation of effects between favorable solvent-mediated interactions among the polyampholytes in the condensed phase and favorable polyampholyte-solvent interactions in the dilute phase, often netting only a minor enhancement of overall LLPS propensity from the very dielectric heterogeneity that arises from the LLPS itself. Further ramifications of this principle are discussed.
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Affiliation(s)
- Jonas Wessén
- Department of Biochemistry, University of Toronto, Medical Sciences Building-5th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Tanmoy Pal
- Department of Biochemistry, University of Toronto, Medical Sciences Building-5th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Suman Das
- Department of Biochemistry, University of Toronto, Medical Sciences Building-5th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Yi-Hsuan Lin
- Department of Biochemistry, University of Toronto, Medical Sciences Building-5th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.,Molecular Medicine, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | - Hue Sun Chan
- Department of Biochemistry, University of Toronto, Medical Sciences Building-5th Floor, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
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14
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Ahlers J, Adams EM, Bader V, Pezzotti S, Winklhofer KF, Tatzelt J, Havenith M. The key role of solvent in condensation: Mapping water in liquid-liquid phase-separated FUS. Biophys J 2021; 120:1266-1275. [PMID: 33515602 PMCID: PMC8059208 DOI: 10.1016/j.bpj.2021.01.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/21/2020] [Accepted: 01/19/2021] [Indexed: 01/09/2023] Open
Abstract
Formation of biomolecular condensates through liquid-liquid phase separation (LLPS) has emerged as a pervasive principle in cell biology, allowing compartmentalization and spatiotemporal regulation of dynamic cellular processes. Proteins that form condensates under physiological conditions often contain intrinsically disordered regions with low-complexity domains. Among them, the RNA-binding proteins FUS and TDP-43 have been a focus of intense investigation because aberrant condensation and aggregation of these proteins is linked to neurodegenerative diseases such as amyotrophic lateral sclerosis and frontotemporal dementia. LLPS occurs when protein-rich condensates form surrounded by a dilute aqueous solution. LLPS is per se entropically unfavorable. Energetically favorable multivalent protein-protein interactions are one important aspect to offset entropic costs. Another proposed aspect is the release of entropically unfavorable preordered hydration water into the bulk. We used attenuated total reflection spectroscopy in the terahertz frequency range to characterize the changes in the hydrogen bonding network accompanying the FUS enrichment in liquid-liquid phase-separated droplets to provide experimental evidence for the key role of the solvent as a thermodynamic driving force. The FUS concentration inside LLPS droplets was determined to be increased to 2.0 mM independent of the initial protein concentration (5 or 10 μM solutions) by fluorescence measurements. With terahertz spectroscopy, we revealed a dewetting of hydrophobic side chains in phase-separated FUS. Thus, the release of entropically unfavorable water populations into the bulk goes hand in hand with enthalpically favorable protein-protein interaction. Both changes are energetically favorable, and our study shows that both contribute to the thermodynamic driving force in phase separation.
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Affiliation(s)
- Jonas Ahlers
- Department Physical Chemistry, Ruhr-University Bochum, Bochum, Germany
| | - Ellen M Adams
- Department Physical Chemistry, Ruhr-University Bochum, Bochum, Germany
| | - Verian Bader
- Department Molecular Cell Biology, Institute of Biochemistry and Pathobiochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Simone Pezzotti
- Department Physical Chemistry, Ruhr-University Bochum, Bochum, Germany
| | - Konstanze F Winklhofer
- Department Molecular Cell Biology, Institute of Biochemistry and Pathobiochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Jörg Tatzelt
- Department Biochemistry of Neurodegenerative Diseases, Institute of Biochemistry and Pathobiochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Martina Havenith
- Department Physical Chemistry, Ruhr-University Bochum, Bochum, Germany.
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15
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Fetahaj Z, Ostermeier L, Cinar H, Oliva R, Winter R. Biomolecular Condensates under Extreme Martian Salt Conditions. J Am Chem Soc 2021; 143:5247-5259. [PMID: 33755443 DOI: 10.1021/jacs.1c01832] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Biomolecular condensates formed by liquid-liquid phase separation (LLPS) are considered one of the early compartmentalization strategies of cells, which still prevail today forming nonmembranous compartments in biological cells. Studies of the effect of high pressures, such as those encountered in the subsurface salt lakes of Mars or in the depths of the subseafloor on Earth, on biomolecular LLPS will contribute to questions of protocell formation under prebiotic conditions. We investigated the effects of extreme environmental conditions, focusing on highly aggressive Martian salts (perchlorate and sulfate) and high pressure, on the formation of biomolecular condensates of proteins. Our data show that the driving force for phase separation of proteins is not only sensitively dictated by their amino acid sequence but also strongly influenced by the type of salt and its concentration. At high salinity, as encountered in Martian soil and similar harsh environments on Earth, attractive short-range interactions, ion correlation effects, hydrophobic, and π-driven interactions can sustain LLPS for suitable polypeptide sequences. Our results also show that salts across the Hofmeister series have a differential effect on shifting the boundary of immiscibility that determines phase separation. In addition, we show that confinement mimicking cracks in sediments and subsurface saline water pools in the Antarctica or on Mars can dramatically stabilize liquid phase droplets, leading to an increase in the temperature and pressure stability of the droplet phase.
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Affiliation(s)
- Zamira Fetahaj
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Street 4a, 44227 Dortmund, Germany
| | - Lena Ostermeier
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Street 4a, 44227 Dortmund, Germany
| | - Hasan Cinar
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Street 4a, 44227 Dortmund, Germany
| | - Rosario Oliva
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Street 4a, 44227 Dortmund, Germany
| | - Roland Winter
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Street 4a, 44227 Dortmund, Germany
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16
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Reentrant liquid condensate phase of proteins is stabilized by hydrophobic and non-ionic interactions. Nat Commun 2021; 12:1085. [PMID: 33597515 PMCID: PMC7889641 DOI: 10.1038/s41467-021-21181-9] [Citation(s) in RCA: 220] [Impact Index Per Article: 73.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 01/08/2021] [Indexed: 01/31/2023] Open
Abstract
Liquid-liquid phase separation of proteins underpins the formation of membraneless compartments in living cells. Elucidating the molecular driving forces underlying protein phase transitions is therefore a key objective for understanding biological function and malfunction. Here we show that cellular proteins, which form condensates at low salt concentrations, including FUS, TDP-43, Brd4, Sox2, and Annexin A11, can reenter a phase-separated regime at high salt concentrations. By bringing together experiments and simulations, we demonstrate that this reentrant phase transition in the high-salt regime is driven by hydrophobic and non-ionic interactions, and is mechanistically distinct from the low-salt regime, where condensates are additionally stabilized by electrostatic forces. Our work thus sheds light on the cooperation of hydrophobic and non-ionic interactions as general driving forces in the condensation process, with important implications for aberrant function, druggability, and material properties of biomolecular condensates.
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17
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Krainer G, Welsh TJ, Joseph JA, Espinosa JR, Wittmann S, de Csilléry E, Sridhar A, Toprakcioglu Z, Gudiškytė G, Czekalska MA, Arter WE, Guillén-Boixet J, Franzmann TM, Qamar S, George-Hyslop PS, Hyman AA, Collepardo-Guevara R, Alberti S, Knowles TPJ. Reentrant liquid condensate phase of proteins is stabilized by hydrophobic and non-ionic interactions. Nat Commun 2021; 12:1085. [PMID: 33597515 DOI: 10.1101/2020.05.04.076299] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 01/08/2021] [Indexed: 05/26/2023] Open
Abstract
Liquid-liquid phase separation of proteins underpins the formation of membraneless compartments in living cells. Elucidating the molecular driving forces underlying protein phase transitions is therefore a key objective for understanding biological function and malfunction. Here we show that cellular proteins, which form condensates at low salt concentrations, including FUS, TDP-43, Brd4, Sox2, and Annexin A11, can reenter a phase-separated regime at high salt concentrations. By bringing together experiments and simulations, we demonstrate that this reentrant phase transition in the high-salt regime is driven by hydrophobic and non-ionic interactions, and is mechanistically distinct from the low-salt regime, where condensates are additionally stabilized by electrostatic forces. Our work thus sheds light on the cooperation of hydrophobic and non-ionic interactions as general driving forces in the condensation process, with important implications for aberrant function, druggability, and material properties of biomolecular condensates.
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Affiliation(s)
- Georg Krainer
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Timothy J Welsh
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Jerelle A Joseph
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, UK
- Department of Genetics, University of Cambridge, Cambridge, UK
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK
| | - Jorge R Espinosa
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, UK
- Department of Genetics, University of Cambridge, Cambridge, UK
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK
| | - Sina Wittmann
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Tatzberg 47/49, Dresden, Germany
| | - Ella de Csilléry
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Akshay Sridhar
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, UK
- Department of Genetics, University of Cambridge, Cambridge, UK
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK
| | - Zenon Toprakcioglu
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Giedre Gudiškytė
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Magdalena A Czekalska
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
- Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka, 44/52 01-224, Warsaw, Poland
| | - William E Arter
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Jordina Guillén-Boixet
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Tatzberg 47/49, Dresden, Germany
| | - Titus M Franzmann
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Tatzberg 47/49, Dresden, Germany
| | - Seema Qamar
- Cambridge Institute for Medical Research, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Peter St George-Hyslop
- Cambridge Institute for Medical Research, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.
- Division of Neurology, Department of Medicine, University of Toronto and University Health Network, Toronto, Ontario, Canada.
| | - Anthony A Hyman
- Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden, Germany.
| | - Rosana Collepardo-Guevara
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, UK.
- Department of Genetics, University of Cambridge, Cambridge, UK.
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK.
| | - Simon Alberti
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Tatzberg 47/49, Dresden, Germany.
| | - Tuomas P J Knowles
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK.
- Cavendish Laboratory, Department of Physics, University of Cambridge, J J Thomson Avenue, Cambridge, UK.
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18
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Levengood JD, Peterson J, Tolbert BS, Roche J. Thermodynamic stability of hnRNP A1 low complexity domain revealed by high-pressure NMR. Proteins 2021; 89:781-791. [PMID: 33550645 DOI: 10.1002/prot.26058] [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: 08/31/2020] [Revised: 12/21/2020] [Accepted: 01/31/2021] [Indexed: 11/09/2022]
Abstract
We have investigated the pressure- and temperature-induced conformational changes associated with the low complexity domain of hnRNP A1, an RNA-binding protein able to phase separate in response to cellular stress. Solution NMR spectra of the hnRNP A1 low-complexity domain fused with protein-G B1 domain were collected from 1 to 2500 bar and from 268 to 290 K. While the GB1 domain shows the typical pressure-induced and cold temperature-induced unfolding expected for small globular domains, the low-complexity domain of hnRNP A1 exhibits unusual pressure and temperature dependences. We observed that the low-complexity domain is pressure sensitive, undergoing a major conformational transition within the prescribed pressure range. Remarkably, this transition has the inverse temperature dependence of a typical folding-unfolding transition. Our results suggest the presence of a low-lying extended and fully solvated state(s) of the low-complexity domain that may play a role in phase separation. This study highlights the exquisite sensitivity of solution NMR spectroscopy to observe subtle conformational changes and illustrates how pressure perturbation can be used to determine the properties of metastable conformational ensembles.
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Affiliation(s)
- Jeffrey D Levengood
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio, USA
| | - Jake Peterson
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa, USA
| | - Blanton S Tolbert
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio, USA
| | - Julien Roche
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa, USA
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19
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Molnár OR, Somkuti J, Smeller L. Negative volume changes of human G-quadruplexes at unfolding. Heliyon 2020; 6:e05702. [PMID: 33354631 PMCID: PMC7744710 DOI: 10.1016/j.heliyon.2020.e05702] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/22/2020] [Accepted: 12/08/2020] [Indexed: 11/16/2022] Open
Abstract
G-quadruplexes are tetrahelical structures. They are important targets for anti-cancer drugs, since they are situated at crucial positions within the genome. We studied the volumetric properties of the unfolding of three G-quadruplexes in the presence of potassium ion. The unfolding volume changes were determined using high-pressure fluorescence spectroscopy. The c-MYC, KIT, and VEGF sequences unfold with the transition volume of -17, -6 and -18 cm3/mol, respectively. The small magnitude of the unfolding volume of KIT could be explained by its unique structure and the lower amount of void volume. Since the cell interior is highly crowded, the available volume is restricted. Therefore the volumetric changes during the conformational transformations gain biological importance.
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Affiliation(s)
- Orsolya Réka Molnár
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
| | - Judit Somkuti
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
| | - László Smeller
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
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20
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Deng J, Walther A. Programmable and Chemically Fueled DNA Coacervates by Transient Liquid-Liquid Phase Separation. Chem 2020; 6:3329-3343. [PMID: 35252623 PMCID: PMC7612463 DOI: 10.1016/j.chempr.2020.09.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Multivalency-driven liquid-liquid phase separation (LLPS) is essential in biomolecular condensates to facilitate spatiotemporal regulation of biological functions. Providing programmable model systems would help to better understand the LLPS processes in biology, and furnish new types of compartmentalized synthetic reaction crucibles that exploit biological principles. Herein, we demonstrate a concept for programming LLPS using transient multivalency between ATP-driven sequence-defined functionalized nucleic acid polymers (SfNAPs), which serve as simple models for membrane-less organelles. The ATP-driven SfNAPs are transiently formed by an enzymatic reaction network (ERN) of concurrent ATP-powered DNA ligation and DNA restriction. The lifetimes can be programmed by the ATP concentration, which manifests on the LLPS length scale in tunable lifetimes for the all-DNA coacervates. Critically, the prominent programmability of the DNA-based building blocks allows to encode distinct molecular recognitions for multiple multivalent systems, enabling sorted LLPS and thus multicomponent DNA coacervates, reminiscent of the diverse membraneless organelles in biological systems. The ATP-driven coacervates are capable for multivalent trapping of micron-scale colloids and biomolecules to generate functions as emphasized for rate enhancements in enzymatic cascades. This work supports ATP-driven multivalent coacervation as a valuable mechanism for dynamic multicomponent and function biomolecular condensate mimics and for autonomous materials design in general.
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Affiliation(s)
- Jie Deng
- ABMS Lab, Institute for Macromolecular Chemistry, University of Freiburg, Stefan-Meier- Straße 31, 79104 Freiburg, Germany
- DFG Cluster of Excellence "Living, Adaptive and Energy-Autonomous Materials Systems" (livMatS), 79110 Freiburg, Germany
- Freiburg Materials Research Center, University of Freiburg, Stefan-Meier-Straße 21, 79104 Freiburg, Germany
- Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT), University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
| | - Andreas Walther
- ABMS Lab, Institute for Macromolecular Chemistry, University of Freiburg, Stefan-Meier- Straße 31, 79104 Freiburg, Germany
- DFG Cluster of Excellence "Living, Adaptive and Energy-Autonomous Materials Systems" (livMatS), 79110 Freiburg, Germany
- Freiburg Materials Research Center, University of Freiburg, Stefan-Meier-Straße 21, 79104 Freiburg, Germany
- Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT), University of Freiburg, Georges-Köhler-Allee 105, 79110 Freiburg, Germany
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21
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Das S, Lin YH, Vernon RM, Forman-Kay JD, Chan HS. Comparative roles of charge, π, and hydrophobic interactions in sequence-dependent phase separation of intrinsically disordered proteins. Proc Natl Acad Sci U S A 2020; 117:28795-28805. [PMID: 33139563 PMCID: PMC7682375 DOI: 10.1073/pnas.2008122117] [Citation(s) in RCA: 131] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Endeavoring toward a transferable, predictive coarse-grained explicit-chain model for biomolecular condensates underlain by liquid-liquid phase separation (LLPS) of proteins, we conducted multiple-chain simulations of the N-terminal intrinsically disordered region (IDR) of DEAD-box helicase Ddx4, as a test case, to assess roles of electrostatic, hydrophobic, cation-π, and aromatic interactions in amino acid sequence-dependent LLPS. We evaluated three different residue-residue interaction schemes with a shared electrostatic potential. Neither a common hydrophobicity scheme nor one augmented with arginine/lysine-aromatic cation-π interactions consistently accounted for available experimental LLPS data on the wild-type, a charge-scrambled, a phenylalanine-to-alanine (FtoA), and an arginine-to-lysine (RtoK) mutant of Ddx4 IDR. In contrast, interactions based on contact statistics among folded globular protein structures reproduce the overall experimental trend, including that the RtoK mutant has a much diminished LLPS propensity. Consistency between simulation and experiment was also found for RtoK mutants of P-granule protein LAF-1, underscoring that, to a degree, important LLPS-driving π-related interactions are embodied in classical statistical potentials. Further elucidation is necessary, however, especially of phenylalanine's role in condensate assembly because experiments on FtoA and tyrosine-to-phenylalanine mutants suggest that LLPS-driving phenylalanine interactions are significantly weaker than posited by common statistical potentials. Protein-protein electrostatic interactions are modulated by relative permittivity, which in general depends on aqueous protein concentration. Analytical theory suggests that this dependence entails enhanced interprotein interactions in the condensed phase but more favorable protein-solvent interactions in the dilute phase. The opposing trends lead to only a modest overall impact on LLPS.
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Affiliation(s)
- Suman Das
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Yi-Hsuan Lin
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
- Molecular Medicine, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Robert M Vernon
- Molecular Medicine, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Julie D Forman-Kay
- Molecular Medicine, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Hue Sun Chan
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada;
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22
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The effects of cosolutes and crowding on the kinetics of protein condensate formation based on liquid-liquid phase separation: a pressure-jump relaxation study. Sci Rep 2020; 10:17245. [PMID: 33057154 PMCID: PMC7566631 DOI: 10.1038/s41598-020-74271-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/15/2020] [Indexed: 01/21/2023] Open
Abstract
Biomolecular assembly processes based on liquid-liquid phase separation (LLPS) are ubiquitous in the biological cell. To fully understand the role of LLPS in biological self-assembly, it is necessary to characterize also their kinetics of formation and dissolution. Here, we introduce the pressure-jump relaxation technique in concert with UV/Vis and FTIR spectroscopy as well as light microscopy to characterize the evolution of LLPS formation and dissolution in a time-dependent manner. As a model system undergoing LLPS we used the globular eye-lens protein γD-crystallin. As cosolutes and macromolecular crowding are known to affect the stability and dynamics of biomolecular condensates in cellulo, we extended our kinetic study by addressing also the impact of urea, the deep-sea osmolyte trimethylamine-N-oxide (TMAO) and a crowding agent on the transformation kinetics of the LLPS system. As a prerequisite for the kinetic studies, the phase diagram of γD-crystallin at the different solution conditions also had to be determined. The formation of the droplet phase was found to be a very rapid process and can be switched on and off on the 1-4 s timescale. Theoretical treatment using the Johnson-Mehl-Avrami-Kolmogorov model indicates that the LLPS proceeds via a diffusion-limited nucleation and growth mechanism at subcritical protein concentrations, a scenario which is also expected to prevail within biologically relevant crowded systems. Compared to the marked effect the cosolutes take on the stability of the LLPS region, their effect at biologically relevant concentrations on the phase transformation kinetics is very small, which might be a particular advantage in the cellular context, as a fast switching capability of the transition should not be compromised by the presence of cellular cosolutes.
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Cinar H, Oliva R, Lin Y, Chen X, Zhang M, Chan HS, Winter R. Pressure Sensitivity of SynGAP/PSD-95 Condensates as a Model for Postsynaptic Densities and Its Biophysical and Neurological Ramifications. Chemistry 2020; 26:11024-11031. [PMID: 31910298 PMCID: PMC7496680 DOI: 10.1002/chem.201905269] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Indexed: 12/11/2022]
Abstract
Biomolecular condensates consisting of proteins and nucleic acids can serve critical biological functions, so that some condensates are referred as membraneless organelles. They can also be disease-causing, if their assembly is misregulated. A major physicochemical basis of the formation of biomolecular condensates is liquid-liquid phase separation (LLPS). In general, LLPS depends on environmental variables, such as temperature and hydrostatic pressure. The effects of pressure on the LLPS of a binary SynGAP/PSD-95 protein system mimicking postsynaptic densities, which are protein assemblies underneath the plasma membrane of excitatory synapses, were investigated. Quite unexpectedly, the model system LLPS is much more sensitive to pressure than the folded states of typical globular proteins. Phase-separated droplets of SynGAP/PSD-95 were found to dissolve into a homogeneous solution already at ten-to-hundred bar levels. The pressure sensitivity of SynGAP/PSD-95 is seen here as a consequence of both pressure-dependent multivalent interaction strength and void volume effects. Considering that organisms in the deep sea are under pressures up to about 1 kbar, this implies that deep-sea organisms have to devise means to counteract this high pressure sensitivity of biomolecular condensates to avoid harm. Intriguingly, these findings may shed light on the biophysical underpinning of pressure-related neurological disorders in terrestrial vertebrates.
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Affiliation(s)
- Hasan Cinar
- Physical Chemistry I—Biophysical ChemistryFaculty of Chemistry and Chemical BiologyTU DortmundOtto-Hahn-Strasse 4a44227DortmundGermany
| | - Rosario Oliva
- Physical Chemistry I—Biophysical ChemistryFaculty of Chemistry and Chemical BiologyTU DortmundOtto-Hahn-Strasse 4a44227DortmundGermany
| | - Yi‐Hsuan Lin
- Department of BiochemistryFaculty of MedicineUniversity of TorontoTorontoOntarioM5S 1A8Canada
- Molecular MedicineHospital for Sick ChildrenTorontoOntarioM5G 0A4Canada
| | - Xudong Chen
- Division of Life ScienceState Key Laboratory of Molecular NeuroscienceHong Kong University of Science and TechnologyClear Water BayKowloon, Hong KongChina
| | - Mingjie Zhang
- Division of Life ScienceState Key Laboratory of Molecular NeuroscienceHong Kong University of Science and TechnologyClear Water BayKowloon, Hong KongChina
| | - Hue Sun Chan
- Department of BiochemistryFaculty of MedicineUniversity of TorontoTorontoOntarioM5S 1A8Canada
| | - Roland Winter
- Physical Chemistry I—Biophysical ChemistryFaculty of Chemistry and Chemical BiologyTU DortmundOtto-Hahn-Strasse 4a44227DortmundGermany
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24
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Oliva R, Banerjee S, Cinar H, Ehrt C, Winter R. Alteration of Protein Binding Affinities by Aqueous Two-Phase Systems Revealed by Pressure Perturbation. Sci Rep 2020; 10:8074. [PMID: 32415277 PMCID: PMC7228918 DOI: 10.1038/s41598-020-65053-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 04/21/2020] [Indexed: 01/29/2023] Open
Abstract
Interactions between proteins and ligands, which are fundamental to many biochemical processes essential to life, are mostly studied at dilute buffer conditions. The effects of the highly crowded nature of biological cells and the effects of liquid-liquid phase separation inducing biomolecular droplet formation as a means of membrane-less compartmentalization have been largely neglected in protein binding studies. We investigated the binding of a small ligand (ANS) to one of the most multifunctional proteins, bovine serum albumin (BSA) in an aqueous two-phase system (ATPS) composed of PEG and Dextran. Also, aiming to shed more light on differences in binding mode compared to the neat buffer data, we examined the effect of high hydrostatic pressure (HHP) on the binding process. We observe a marked effect of the ATPS on the binding characteristics of BSA. Not only the binding constants change in the ATPS system, but also the integrity of binding sites is partially lost, which is most likely due to soft enthalpic interactions of the BSA with components in the dense droplet phase of the ATPS. Using pressure modulation, differences in binding sites could be unravelled by their different volumetric and hydration properties. Regarding the vital biological relevance of the study, we notice that extreme biological environments, such as HHP, can markedly affect the binding characteristics of proteins. Hence, organisms experiencing high-pressure stress in the deep sea need to finely adjust the volume changes of their biochemical reactions in cellulo.
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Affiliation(s)
- Rosario Oliva
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227, Dortmund, Germany.
| | - Sudeshna Banerjee
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227, Dortmund, Germany
| | - Hasan Cinar
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227, Dortmund, Germany
| | - Christiane Ehrt
- Medicinal Chemistry - Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227, Dortmund, Germany
| | - Roland Winter
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227, Dortmund, Germany.
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25
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Abstract
Many biomolecular condensates appear to form via spontaneous or driven processes that have the hallmarks of intracellular phase transitions. This suggests that a common underlying physical framework might govern the formation of functionally and compositionally unrelated biomolecular condensates. In this review, we summarize recent work that leverages a stickers-and-spacers framework adapted from the field of associative polymers for understanding how multivalent protein and RNA molecules drive phase transitions that give rise to biomolecular condensates. We discuss how the valence of stickers impacts the driving forces for condensate formation and elaborate on how stickers can be distinguished from spacers in different contexts. We touch on the impact of sticker- and spacer-mediated interactions on the rheological properties of condensates and show how the model can be mapped to known drivers of different types of biomolecular condensates.
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Affiliation(s)
- Jeong-Mo Choi
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, 63130, USA; , ,
- Center for Science & Engineering of Living Systems (CSELS), Washington University in St. Louis, St. Louis, Missouri, 63130, USA
- Natural Science Research Institute, Korea Advanced Institute of Science and Technology (KAIST), Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Alex S Holehouse
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, 63130, USA; , ,
- Center for Science & Engineering of Living Systems (CSELS), Washington University in St. Louis, St. Louis, Missouri, 63130, USA
| | - Rohit V Pappu
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, 63130, USA; , ,
- Center for Science & Engineering of Living Systems (CSELS), Washington University in St. Louis, St. Louis, Missouri, 63130, USA
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26
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Abstract
TDP-43 is an essential RNA-binding protein that assembles into protein inclusions in >95% of cases of amyotrophic lateral sclerosis (ALS). A partially helical region in the predominantly disordered C-terminal domain harbors several mutations associated with ALS and is important for TDP-43 function and liquid–liquid phase separation. We directly demonstrate that this helical region undergoes large structural changes upon helix–helix dimerization and that point mutations can enhance helix–helix assembly. Furthermore, we demonstrate that these point variants can be used to control the material properties of phase-separated TDP-43 constructs in cells and can enhance TDP-43 RNA-splicing function. Therefore, engineered forms of the TDP-43 helical domain could be used to control in-cell phase separation, dynamic assembly, and function. Liquid–liquid phase separation (LLPS) is involved in the formation of membraneless organelles (MLOs) associated with RNA processing. The RNA-binding protein TDP-43 is present in several MLOs, undergoes LLPS, and has been linked to the pathogenesis of amyotrophic lateral sclerosis (ALS). While some ALS-associated mutations in TDP-43 disrupt self-interaction and function, here we show that designed single mutations can enhance TDP-43 assembly and function via modulating helical structure. Using molecular simulation and NMR spectroscopy, we observe large structural changes upon dimerization of TDP-43. Two conserved glycine residues (G335 and G338) are potent inhibitors of helical extension and helix–helix interaction, which are removed in part by variants at these positions, including the ALS-associated G335D. Substitution to helix-enhancing alanine at either of these positions dramatically enhances phase separation in vitro and decreases fluidity of phase-separated TDP-43 reporter compartments in cells. Furthermore, G335A increases TDP-43 splicing function in a minigene assay. Therefore, the TDP-43 helical region serves as a short but uniquely tunable module where application of biophysical principles can precisely control assembly and function in cellular and synthetic biology applications of LLPS.
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27
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Oliva R, Banerjee S, Cinar H, Winter R. Modulation of enzymatic activity by aqueous two-phase systems and pressure – rivalry between kinetic constants. Chem Commun (Camb) 2020; 56:395-398. [DOI: 10.1039/c9cc08065a] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Both, pressure and aqueous two-phase systems are able to modulate the kinetic parameters of enzymatic reactions.
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Affiliation(s)
- Rosario Oliva
- Physical Chemistry I – Biophysical Chemistry
- Faculty of Chemistry and Chemical Biology
- TU Dortmund University
- D-44227 Dortmund
- Germany
| | - Sudeshna Banerjee
- Physical Chemistry I – Biophysical Chemistry
- Faculty of Chemistry and Chemical Biology
- TU Dortmund University
- D-44227 Dortmund
- Germany
| | - Hasan Cinar
- Physical Chemistry I – Biophysical Chemistry
- Faculty of Chemistry and Chemical Biology
- TU Dortmund University
- D-44227 Dortmund
- Germany
| | - Roland Winter
- Physical Chemistry I – Biophysical Chemistry
- Faculty of Chemistry and Chemical Biology
- TU Dortmund University
- D-44227 Dortmund
- Germany
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28
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Cinar H, Fetahaj Z, Cinar S, Vernon RM, Chan HS, Winter RHA. Temperature, Hydrostatic Pressure, and Osmolyte Effects on Liquid-Liquid Phase Separation in Protein Condensates: Physical Chemistry and Biological Implications. Chemistry 2019; 25:13049-13069. [PMID: 31237369 DOI: 10.1002/chem.201902210] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/23/2019] [Indexed: 01/04/2023]
Abstract
Liquid-liquid phase separation (LLPS) of proteins and other biomolecules play a critical role in the organization of extracellular materials and membrane-less compartmentalization of intra-organismal spaces through the formation of condensates. Structural properties of such mesoscopic droplet-like states were studied by spectroscopy, microscopy, and other biophysical techniques. The temperature dependence of biomolecular LLPS has been studied extensively, indicating that phase-separated condensed states of proteins can be stabilized or destabilized by increasing temperature. In contrast, the physical and biological significance of hydrostatic pressure on LLPS is less appreciated. Summarized here are recent investigations of protein LLPS under pressures up to the kbar-regime. Strikingly, for the cases studied thus far, LLPSs of both globular proteins and intrinsically disordered proteins/regions are typically more sensitive to pressure than the folding of proteins, suggesting that organisms inhabiting the deep sea and sub-seafloor sediments, under pressures up to 1 kbar and beyond, have to mitigate this pressure-sensitivity to avoid unwanted destabilization of their functional biomolecular condensates. Interestingly, we found that trimethylamine-N-oxide (TMAO), an osmolyte upregulated in deep-sea fish, can significantly stabilize protein droplets under pressure, pointing to another adaptive advantage for increased TMAO concentrations in deep-sea organisms besides the osmolyte's stabilizing effect against protein unfolding. As life on Earth might have originated in the deep sea, pressure-dependent LLPS is pertinent to questions regarding prebiotic proto-cells. Herein, we offer a conceptual framework for rationalizing the recent experimental findings and present an outline of the basic thermodynamics of temperature-, pressure-, and osmolyte-dependent LLPS as well as a molecular-level statistical mechanics picture in terms of solvent-mediated interactions and void volumes.
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Affiliation(s)
- Hasan Cinar
- Physical Chemistry I-Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Strasse 4a, 44227, Dortmund, Germany
| | - Zamira Fetahaj
- Physical Chemistry I-Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Strasse 4a, 44227, Dortmund, Germany
| | - Süleyman Cinar
- Physical Chemistry I-Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Strasse 4a, 44227, Dortmund, Germany
| | - Robert M Vernon
- Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario, M5G 0A4, Canada
| | - Hue Sun Chan
- Department of Biochemistry, Faculty of Medicine, University of Toronto, Ontario, M5S 1A8, Canada.,Department of Molecular Genetics, Faculty of Medicine, University of Toronto, Ontario, M5S 1A8, Canada
| | - Roland H A Winter
- Physical Chemistry I-Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Strasse 4a, 44227, Dortmund, Germany
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29
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Winter R. Interrogating the Structural Dynamics and Energetics of Biomolecular Systems with Pressure Modulation. Annu Rev Biophys 2019; 48:441-463. [DOI: 10.1146/annurev-biophys-052118-115601] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
High hydrostatic pressure affects the structure, dynamics, and stability of biomolecular systems and is a key parameter in the context of the exploration of the origin and the physical limits of life. This review lays out the conceptual framework for exploring the conformational fluctuations, dynamical properties, and activity of biomolecular systems using pressure perturbation. Complementary pressure-jump relaxation studies are useful tools to study the kinetics and mechanisms of biomolecular phase transitions and structural transformations, such as membrane fusion or protein and nucleic acid folding. Finally, the advantages of using pressure to explore biomolecular assemblies and modulate enzymatic reactions are discussed.
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Affiliation(s)
- Roland Winter
- Faculty of Chemistry and Chemical Biology, Biophysical Chemistry, TU Dortmund University, D-44227 Dortmund, Germany
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30
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Cinar S, Cinar H, Chan HS, Winter R. Pressure-Sensitive and Osmolyte-Modulated Liquid–Liquid Phase Separation of Eye-Lens γ-Crystallins. J Am Chem Soc 2019; 141:7347-7354. [DOI: 10.1021/jacs.8b13636] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Süleyman Cinar
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
| | - Hasan Cinar
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
| | - Hue Sun Chan
- Departments of Biochemistry and Molecular Genetics, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Roland Winter
- Physical Chemistry I - Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
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31
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Julius K, Weine J, Gao M, Latarius J, Elbers M, Paulus M, Tolan M, Winter R. Impact of Macromolecular Crowding and Compression on Protein–Protein Interactions and Liquid–Liquid Phase Separation Phenomena. Macromolecules 2019. [DOI: 10.1021/acs.macromol.8b02476] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Karin Julius
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Jonathan Weine
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Mimi Gao
- Physical Chemistry I−Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 4a, 44227 Dortmund, Germany
| | - Jan Latarius
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Mirko Elbers
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Michael Paulus
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Metin Tolan
- Experimental Physics EIA/DELTA−Department of Physics, TU Dortmund University, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Roland Winter
- Physical Chemistry I−Biophysical Chemistry, Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 4a, 44227 Dortmund, Germany
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32
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Arns L, Winter R. Liquid–liquid phase separation rescues the conformational stability of a DNA hairpin from pressure–stress. Chem Commun (Camb) 2019; 55:10673-10676. [DOI: 10.1039/c9cc04967c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Aqueous two-phase systems are able to rescue the conformational stability of DNA hairpins under harsh environmental conditions.
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Affiliation(s)
- Loana Arns
- Physical Chemistry I – Biophysical Chemistry
- Faculty of Chemistry and Chemical Biology
- TU Dortmund University
- D-44227 Dortmund
- Germany
| | - Roland Winter
- Physical Chemistry I – Biophysical Chemistry
- Faculty of Chemistry and Chemical Biology
- TU Dortmund University
- D-44227 Dortmund
- Germany
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33
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Das S, Amin AN, Lin YH, Chan HS. Coarse-grained residue-based models of disordered protein condensates: utility and limitations of simple charge pattern parameters. Phys Chem Chem Phys 2018; 20:28558-28574. [PMID: 30397688 DOI: 10.1039/c8cp05095c] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Biomolecular condensates undergirded by phase separations of proteins and nucleic acids serve crucial biological functions. To gain physical insights into their genetic basis, we study how liquid-liquid phase separation (LLPS) of intrinsically disordered proteins (IDPs) depends on their sequence charge patterns using a continuum Langevin chain model wherein each amino acid residue is represented by a single bead. Charge patterns are characterized by the "blockiness" measure κ and the "sequence charge decoration" (SCD) parameter. Consistent with random phase approximation (RPA) theory and lattice simulations, LLPS propensity as characterized by critical temperature Tcr* increases with increasingly negative SCD for a set of sequences showing a positive correlation between κ and -SCD. Relative to RPA, the simulated sequence-dependent variation in Tcr* is often-though not always-smaller, whereas the simulated critical volume fractions are higher. However, for a set of sequences exhibiting an anti-correlation between κ and -SCD, the simulated Tcr*'s are quite insensitive to either parameter. Additionally, we find that blocky sequences that allow for strong electrostatic repulsion can lead to coexistence curves with upward concavity as stipulated by RPA, but the LLPS propensity of a strictly alternating charge sequence was likely overestimated by RPA and lattice models because interchain stabilization of this sequence requires spatial alignments that are difficult to achieve in real space. These results help delineate the utility and limitations of the charge pattern parameters and of RPA, pointing to further efforts necessary for rationalizing the newly observed subtleties.
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Affiliation(s)
- Suman Das
- Department of Biochemistry, University of Toronto, Medical Sciences Building - 5th Fl., 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.
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34
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Advances in Understanding Stimulus-Responsive Phase Behavior of Intrinsically Disordered Protein Polymers. J Mol Biol 2018; 430:4619-4635. [DOI: 10.1016/j.jmb.2018.06.031] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 06/12/2018] [Accepted: 06/18/2018] [Indexed: 12/20/2022]
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