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Kang HW, Nguyen L, An S, Kyoung M. Mechanistic insights into condensate formation of human liver-type phosphofructokinase by stochastic modeling approaches. Sci Rep 2024; 14:19011. [PMID: 39152221 PMCID: PMC11329711 DOI: 10.1038/s41598-024-69534-w] [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: 10/05/2023] [Accepted: 08/06/2024] [Indexed: 08/19/2024] Open
Abstract
Human liver-type phosphofructokinase 1 (PFKL) has been shown to regulate glucose flux as a scaffolder arranging glycolytic and gluconeogenic enzymes into a multienzyme metabolic condensate, the glucosome. However, it has remained elusive of how phase separation of PFKL is governed and initiates glucosome formation in living cells, thus hampering to understand a mechanism of glucosome formation and its functional contribution to human cells. In this work, we developed a stochastic model in silico using the principle of Langevin dynamics to investigate how biological properties of PFKL contribute to the condensate formation. The significance of an intermolecular interaction between PFKLs, an effective concentration of PFKL at a region of interest, and its own self-assembled filaments in formation of PFKL condensates and control of their sizes were demonstrated by molecular dynamics simulation using the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS). Such biological properties that define intracellular dynamics of PFKL appear to be essential for phase separation of PFKL, which may represent an initiation step for the formation of glucosome condensates. Collectively, our computational study provides mechanistic insights of glucosome formation, particularly an initial stage through the formation of PFKL condensates in living human cells.
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Affiliation(s)
- Hye-Won Kang
- Department of Mathematics and Statistics, University of Maryland Baltimore County (UMBC), 1000 Hilltop Circle, Baltimore, MD, 21250, USA.
| | - Luan Nguyen
- Department of Mathematics and Statistics, University of Maryland Baltimore County (UMBC), 1000 Hilltop Circle, Baltimore, MD, 21250, USA
| | - Songon An
- Department of Chemistry and Biochemistry, University of Maryland Baltimore County (UMBC), 1000 Hilltop Circle, Baltimore, MD, 21250, USA
- Program in Oncology, Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, MD, 21201, USA
| | - Minjoung Kyoung
- Department of Chemistry and Biochemistry, University of Maryland Baltimore County (UMBC), 1000 Hilltop Circle, Baltimore, MD, 21250, USA.
- Program in Oncology, Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, MD, 21201, USA.
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2
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Xiao YX, Lee SY, Aguilera-Uribe M, Samson R, Au A, Khanna Y, Liu Z, Cheng R, Aulakh K, Wei J, Farias AG, Reilly T, Birkadze S, Habsid A, Brown KR, Chan K, Mero P, Huang JQ, Billmann M, Rahman M, Myers C, Andrews BJ, Youn JY, Yip CM, Rotin D, Derry WB, Forman-Kay JD, Moses AM, Pritišanac I, Gingras AC, Moffat J. The TSC22D, WNK, and NRBP gene families exhibit functional buffering and evolved with Metazoa for cell volume regulation. Cell Rep 2024; 43:114417. [PMID: 38980795 DOI: 10.1016/j.celrep.2024.114417] [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: 02/22/2024] [Revised: 05/08/2024] [Accepted: 06/13/2024] [Indexed: 07/11/2024] Open
Abstract
The ability to sense and respond to osmotic fluctuations is critical for the maintenance of cellular integrity. We used gene co-essentiality analysis to identify an unappreciated relationship between TSC22D2, WNK1, and NRBP1 in regulating cell volume homeostasis. All of these genes have paralogs and are functionally buffered for osmo-sensing and cell volume control. Within seconds of hyperosmotic stress, TSC22D, WNK, and NRBP family members physically associate into biomolecular condensates, a process that is dependent on intrinsically disordered regions (IDRs). A close examination of these protein families across metazoans revealed that TSC22D genes evolved alongside a domain in NRBPs that specifically binds to TSC22D proteins, which we have termed NbrT (NRBP binding region with TSC22D), and this co-evolution is accompanied by rapid IDR length expansion in WNK-family kinases. Our study reveals that TSC22D, WNK, and NRBP genes evolved in metazoans to co-regulate rapid cell volume changes in response to osmolarity.
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Affiliation(s)
- Yu-Xi Xiao
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Seon Yong Lee
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Magali Aguilera-Uribe
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Reuben Samson
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada; The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health, Toronto, ON, Canada
| | - Aaron Au
- Institute for Biomedical Engineering, University of Toronto, Toronto, ON, Canada; Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada; Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Yukti Khanna
- Otto-Loewi Research Center, Division of Medicinal Chemistry, Medical University of Graz, Neue Stiftingtalstrabe 6, 8010, Graz, Austria
| | - Zetao Liu
- Program in Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada; Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Ran Cheng
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada; Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Kamaldeep Aulakh
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Jiarun Wei
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Adrian Granda Farias
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Taylor Reilly
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Saba Birkadze
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Andrea Habsid
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Kevin R Brown
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Katherine Chan
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Patricia Mero
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Jie Qi Huang
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada; Program in Molecular Medicine, The Hospital for Sick Children, Toronto, ON, Canada
| | - Maximilian Billmann
- Institute of Human Genetics, School of Medicine and University Hospital Bonn, University of Bonn, 53127 Bonn, Germany
| | - Mahfuzur Rahman
- Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Chad Myers
- Department of Computer Science and Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Brenda J Andrews
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada; Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Ji-Young Youn
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada; Program in Molecular Medicine, The Hospital for Sick Children, Toronto, ON, Canada
| | - Christopher M Yip
- Institute for Biomedical Engineering, University of Toronto, Toronto, ON, Canada; Donnelly Centre, University of Toronto, Toronto, ON, Canada
| | - Daniela Rotin
- Program in Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada; Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - W Brent Derry
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada; Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Julie D Forman-Kay
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada; Program in Molecular Medicine, The Hospital for Sick Children, Toronto, ON, Canada
| | - Alan M Moses
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | - Iva Pritišanac
- Otto-Loewi Research Center, Division of Medicinal Chemistry, Medical University of Graz, Neue Stiftingtalstrabe 6, 8010, Graz, Austria
| | - Anne-Claude Gingras
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada; The Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Sinai Health, Toronto, ON, Canada
| | - Jason Moffat
- Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada; Institute for Biomedical Engineering, University of Toronto, Toronto, ON, Canada.
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3
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Xie J, Huck WTS, Bao M. Unveiling the Intricate Connection: Cell Volume as a Key Regulator of Mechanotransduction. Annu Rev Biophys 2024; 53:299-317. [PMID: 38424091 DOI: 10.1146/annurev-biophys-030822-035656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
The volumes of living cells undergo dynamic changes to maintain the cells' structural and functional integrity in many physiological processes. Minor fluctuations in cell volume can serve as intrinsic signals that play a crucial role in cell fate determination during mechanotransduction. In this review, we discuss the variability of cell volume and its role in vivo, along with an overview of the mechanisms governing cell volume regulation. Additionally, we provide insights into the current approaches used to control cell volume in vitro. Furthermore, we summarize the biological implications of cell volume regulation and discuss recent advances in understanding the fundamental relationship between cell volume and mechanotransduction. Finally, we delve into the potential underlying mechanisms, including intracellular macromolecular crowding and cellular mechanics, that govern the global regulation of cell fate in response to changes in cell volume. By exploring the intricate interplay between cell volume and mechanotransduction, we underscore the importance of considering cell volume as a fundamental signaling cue to unravel the basic principles of mechanotransduction. Additionally, we propose future research directions that can extend our current understanding of cell volume in mechanotransduction. Overall, this review highlights the significance of considering cell volume as a fundamental signal in understanding the basic principles in mechanotransduction and points out the possibility of controlling cell volume to control cell fate, mitigate disease-related damage, and facilitate the healing of damaged tissues.
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Affiliation(s)
- Jing Xie
- Institute of Biomedical Engineering, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, Chengdu, China
| | - Wilhelm T S Huck
- Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands;
| | - Min Bao
- Oujiang Laboratory (Zhejiang Lab for Regenerative Medicine, Vision and Brain Health), First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China;
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4
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Li P, Chen P, Qi F, Shi J, Zhu W, Li J, Zhang P, Xie H, Li L, Lei M, Ren X, Wang W, Zhang L, Xiang X, Zhang Y, Gao Z, Feng X, Du W, Liu X, Xia L, Liu BF, Li Y. High-throughput and proteome-wide discovery of endogenous biomolecular condensates. Nat Chem 2024; 16:1101-1112. [PMID: 38499848 DOI: 10.1038/s41557-024-01485-1] [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: 09/23/2022] [Accepted: 02/23/2024] [Indexed: 03/20/2024]
Abstract
Phase separation inside mammalian cells regulates the formation of the biomolecular condensates that are related to gene expression, signalling, development and disease. However, a large population of endogenous condensates and their candidate phase-separating proteins have yet to be discovered in a quantitative and high-throughput manner. Here we demonstrate that endogenously expressed biomolecular condensates can be identified across a cell's proteome by sorting proteins across varying oligomeric states. We employ volumetric compression to modulate the concentrations of intracellular proteins and the degree of crowdedness, which are physical regulators of cellular biomolecular condensates. The changes in degree of the partition of proteins into condensates or phase separation led to varying oligomeric states of the proteins, which can be detected by coupling density gradient ultracentrifugation and quantitative mass spectrometry. In total, we identified 1,518 endogenous condensate proteins, of which 538 have not been reported before. Furthermore, we demonstrate that our strategy can identify condensate proteins that respond to specific biological processes.
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Affiliation(s)
- Pengjie Li
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Peng Chen
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Fukang Qi
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Jinyun Shi
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Wenjie Zhu
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Jiashuo Li
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Peng Zhang
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Han Xie
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Lina Li
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Mengcheng Lei
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Xueqing Ren
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Wenhui Wang
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Liang Zhang
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Xufu Xiang
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Yiwei Zhang
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Zhaolong Gao
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Xiaojun Feng
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Wei Du
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Xin Liu
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Limin Xia
- Department of Gastroenterology, Hubei Key Laboratory of Hepato-Pancreato-Biliary Diseases, Institute of Liver and Gastrointestinal Diseases, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Bi-Feng Liu
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.
| | - Yiwei Li
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics and Molecular Imaging Key Laboratory, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.
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5
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Cohen SR, Banerjee PR, Pappu RV. Direct computations of viscoelastic moduli of biomolecular condensates. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.11.598543. [PMID: 38915484 PMCID: PMC11195242 DOI: 10.1101/2024.06.11.598543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
In vitro facsimiles of biomolecular condensates are formed by different types of intrinsically disordered proteins including prion-like low complexity domains (PLCDs). PLCD condensates are viscoelastic materials defined by time-dependent, sequence-specific complex shear moduli. Here, we show that viscoelastic moduli can be computed directly using a generalization of the Rouse model and information regarding intra- and inter-chain contacts that is extracted from equilibrium configurations of lattice-based Metropolis Monte Carlo (MMC) simulations. The key ingredient of the generalized Rouse model is the Zimm matrix that we compute from equilibrium MMC simulations. We compute two flavors of Zimm matrices, one referred to as the single-chain model that accounts only for intra-chain contacts, and the other referred to as a collective model, that accounts for inter-chain interactions. The single-chain model systematically overestimates the storage and loss moduli, whereas the collective model reproduces the measured moduli with greater fidelity. However, in the long time, low-frequency domain, a mixture of the two models proves to be most accurate. In line with the theory of Rouse, we find that a continuous distribution of relaxation times exists in condensates. The single crossover frequency between dominantly elastic versus dominantly viscous behaviors is influenced by the totality of the relaxation modes. Hence, our analysis suggests that viscoelastic fluid-like condensates are best described as generalized Maxwell fluids. Finally, we show that the complex shear moduli can be used to solve an inverse problem to obtain distributions of relaxation times that underlie the dynamics within condensates.
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Subramanya AR, Boyd-Shiwarski CR. Molecular Crowding: Physiologic Sensing and Control. Annu Rev Physiol 2024; 86:429-452. [PMID: 37931170 DOI: 10.1146/annurev-physiol-042222-025920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
The cytoplasm is densely packed with molecules that contribute to its nonideal behavior. Cytosolic crowding influences chemical reaction rates, intracellular water mobility, and macromolecular complex formation. Overcrowding is potentially catastrophic; to counteract this problem, cells have evolved acute and chronic homeostatic mechanisms that optimize cellular crowdedness. Here, we provide a physiology-focused overview of molecular crowding, highlighting contemporary advances in our understanding of its sensing and control. Long hypothesized as a form of crowding-induced microcompartmentation, phase separation allows cells to detect and respond to intracellular crowding through the action of biomolecular condensates, as indicated by recent studies. Growing evidence indicates that crowding is closely tied to cell size and fluid volume, homeostatic responses to physical compression and desiccation, tissue architecture, circadian rhythm, aging, transepithelial transport, and total body electrolyte and water balance. Thus, molecular crowding is a fundamental physiologic parameter that impacts diverse functions extending from molecule to organism.
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Affiliation(s)
- Arohan R Subramanya
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; ,
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Pittsburgh Center for Kidney Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- VA Pittsburgh Healthcare System, Pittsburgh, Pennsylvania, USA
| | - Cary R Boyd-Shiwarski
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA; ,
- Pittsburgh Center for Kidney Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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7
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Collette D, Dunlap D, Finzi L. Macromolecular Crowding and DNA: Bridging the Gap between In Vitro and In Vivo. Int J Mol Sci 2023; 24:17502. [PMID: 38139331 PMCID: PMC10744201 DOI: 10.3390/ijms242417502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/29/2023] [Accepted: 12/05/2023] [Indexed: 12/24/2023] Open
Abstract
The cellular environment is highly crowded, with up to 40% of the volume fraction of the cell occupied by various macromolecules. Most laboratory experiments take place in dilute buffer solutions; by adding various synthetic or organic macromolecules, researchers have begun to bridge the gap between in vitro and in vivo measurements. This is a review of the reported effects of macromolecular crowding on the compaction and extension of DNA, the effect of macromolecular crowding on DNA kinetics, and protein-DNA interactions. Theoretical models related to macromolecular crowding and DNA are briefly reviewed. Gaps in the literature, including the use of biologically relevant crowders, simultaneous use of multi-sized crowders, empirical connections between macromolecular crowding and liquid-liquid phase separation of nucleic materials are discussed.
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Affiliation(s)
| | | | - Laura Finzi
- Department of Physics, College of Arts & Sciences, Emory University, Atlanta, GA 30322, USA; (D.C.); (D.D.)
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8
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Junier I, Ghobadpour E, Espeli O, Everaers R. DNA supercoiling in bacteria: state of play and challenges from a viewpoint of physics based modeling. Front Microbiol 2023; 14:1192831. [PMID: 37965550 PMCID: PMC10642903 DOI: 10.3389/fmicb.2023.1192831] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 09/25/2023] [Indexed: 11/16/2023] Open
Abstract
DNA supercoiling is central to many fundamental processes of living organisms. Its average level along the chromosome and over time reflects the dynamic equilibrium of opposite activities of topoisomerases, which are required to relax mechanical stresses that are inevitably produced during DNA replication and gene transcription. Supercoiling affects all scales of the spatio-temporal organization of bacterial DNA, from the base pair to the large scale chromosome conformation. Highlighted in vitro and in vivo in the 1960s and 1970s, respectively, the first physical models were proposed concomitantly in order to predict the deformation properties of the double helix. About fifteen years later, polymer physics models demonstrated on larger scales the plectonemic nature and the tree-like organization of supercoiled DNA. Since then, many works have tried to establish a better understanding of the multiple structuring and physiological properties of bacterial DNA in thermodynamic equilibrium and far from equilibrium. The purpose of this essay is to address upcoming challenges by thoroughly exploring the relevance, predictive capacity, and limitations of current physical models, with a specific focus on structural properties beyond the scale of the double helix. We discuss more particularly the problem of DNA conformations, the interplay between DNA supercoiling with gene transcription and DNA replication, its role on nucleoid formation and, finally, the problem of scaling up models. Our primary objective is to foster increased collaboration between physicists and biologists. To achieve this, we have reduced the respective jargon to a minimum and we provide some explanatory background material for the two communities.
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Affiliation(s)
- Ivan Junier
- CNRS, UMR 5525, VetAgro Sup, Grenoble INP, TIMC, Université Grenoble Alpes, Grenoble, France
| | - Elham Ghobadpour
- CNRS, UMR 5525, VetAgro Sup, Grenoble INP, TIMC, Université Grenoble Alpes, Grenoble, France
- École Normale Supérieure (ENS) de Lyon, CNRS, Laboratoire de Physique and Centre Blaise Pascal de l'ENS de Lyon, Lyon, France
| | - Olivier Espeli
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Ralf Everaers
- École Normale Supérieure (ENS) de Lyon, CNRS, Laboratoire de Physique and Centre Blaise Pascal de l'ENS de Lyon, Lyon, France
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9
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Forsdyke DR. Aggregation-prone peptides from within a non-self-protein homoaggregate are preferred for MHC association: Historical overview. Scand J Immunol 2023; 98:e13306. [PMID: 38441340 DOI: 10.1111/sji.13306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 06/02/2023] [Accepted: 06/12/2023] [Indexed: 03/07/2024]
Abstract
New technologies assist re-evaluation of hypotheses on generation of immune cell repertoires and distinctions of self from non-self. Findings include positive correlations between peptide propensities to aggregate and their binding to major histocompatibility complex (MHC) proteins. This recalls the hypothesis that foreign proteins may homoaggregate in host cytosols prior to releasing their peptides (p) to form pMHC complexes. Clues to this included aggregation-related phenomena associated with infections (rouleaux formation, pyrexia, certain brain diseases). By virtue of 'promiscuous' gene expression by thymic presenting cells - perhaps adapted from earlier evolving gonadal mechanisms - developing T cells monitor surface pMHC clusterings. This evaluates intracellular concentrations of the corresponding proteins, and hence, following Burnet's two signal principle, degrees of self-reactivity. After positive selection in the thymic cortex for reactivity with 'near-self', high-level pMHC clustering suffices in the medulla for negatively selection. Following Burnet's principle, in the periphery low-level clustering suffices for T cell stimulation and high-level clustering again provokes negative selection (immunological tolerance). For evolving intracellular pathogens, fine-tuned polymorphisms of their host species have limited to 'near-self' some mimicking adaptations. It is proposed that while entire pathogen proteins may have evolved to minimize their aggregability, the greater aggregability of their peptides remains partially hidden within. Two-step proofreading mechanisms in prospective hosts select proteins containing aggregable peptide for the generation of pMHC clusters at the surface of presenting cells. Through mutations, some proteins of pathogens and cancer cells tend to converge towards the host 'near-self' that its T cells have auditioned to address.
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Affiliation(s)
- Donald R Forsdyke
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
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10
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Ferreira PA. Nucleocytoplasmic transport at the crossroads of proteostasis, neurodegeneration and neuroprotection. FEBS Lett 2023; 597:2567-2589. [PMID: 37597509 DOI: 10.1002/1873-3468.14722] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 08/04/2023] [Accepted: 08/05/2023] [Indexed: 08/21/2023]
Abstract
Nucleocytoplasmic transport comprises the multistep assembly, transport, and disassembly of protein and RNA cargoes entering and exiting nuclear pores. Accruing evidence supports that impairments to nucleocytoplasmic transport are a hallmark of neurodegenerative diseases. These impairments cause dysregulations in nucleocytoplasmic partitioning and proteostasis of nuclear transport receptors and client substrates that promote intracellular deposits - another hallmark of neurodegeneration. Disturbances in liquid-liquid phase separation (LLPS) between dense and dilute phases of biomolecules implicated in nucleocytoplasmic transport promote micrometer-scale coacervates, leading to proteinaceous aggregates. This Review provides historical and emerging principles of LLPS at the interface of nucleocytoplasmic transport, proteostasis, aging and noxious insults, whose dysregulations promote intracellular aggregates. E3 SUMO-protein ligase Ranbp2 constitutes the cytoplasmic filaments of nuclear pores, where it acts as a molecular hub for rate-limiting steps of nucleocytoplasmic transport. A vignette is provided on the roles of Ranbp2 in nucleocytoplasmic transport and at the intersection of proteostasis in the survival of photoreceptor and motor neurons under homeostatic and pathophysiological environments. Current unmet clinical needs are highlighted, including therapeutics aiming to manipulate aggregation-dissolution models of purported neurotoxicity in neurodegeneration.
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Affiliation(s)
- Paulo A Ferreira
- Department of Ophthalmology, Department of Pathology, Duke University Medical Center, NC, Durham, USA
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11
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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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12
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Abstract
Multivalent proteins and nucleic acids, collectively referred to as multivalent associative biomacromolecules, provide the driving forces for the formation and compositional regulation of biomolecular condensates. Here, we review the key concepts of phase transitions of aqueous solutions of associative biomacromolecules, specifically proteins that include folded domains and intrinsically disordered regions. The phase transitions of these systems come under the rubric of coupled associative and segregative transitions. The concepts underlying these processes are presented, and their relevance to biomolecular condensates is discussed.
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Affiliation(s)
- Rohit V Pappu
- Department of Biomedical Engineering, Center for Biomolecular Condensates (CBC), Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Samuel R Cohen
- Department of Biomedical Engineering, Center for Biomolecular Condensates (CBC), Washington University in St. Louis, St. Louis, Missouri 63130, United States
- Center of Regenerative Medicine, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Furqan Dar
- Department of Biomedical Engineering, Center for Biomolecular Condensates (CBC), Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Mina Farag
- Department of Biomedical Engineering, Center for Biomolecular Condensates (CBC), Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Mrityunjoy Kar
- Max Planck Institute of Cell Biology and Genetics, 01307 Dresden, Germany
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13
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Babaki M, Fedosov DA, Gholivand A, Opdam J, Tuinier R, Lettinga MP. Competition between deformation and free volume quantified by 3D image analysis of red blood cell. Biophys J 2023; 122:1646-1658. [PMID: 36964658 PMCID: PMC10183325 DOI: 10.1016/j.bpj.2023.03.030] [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: 11/25/2022] [Revised: 02/14/2023] [Accepted: 03/21/2023] [Indexed: 03/26/2023] Open
Abstract
Cells in living organisms are subjected to mechanical strains caused by external forces like overcrowding, resulting in strong deformations that affect cell function. We study the interplay between deformation and crowding of red blood cells (RBCs) in dispersions of nonabsorbing rod-like viruses. We identify a sequence of configurational transitions of RBC doublets, including configurations that can only be induced by long-ranged attraction: highly fluctuating T-shaped and face-to-face configurations at low, and doublets approaching a complete spherical configuration at high, rod concentrations. Complementary simulations are used to explore different energy contributions to deformation as well as the stability of RBC doublet configurations. Our advanced analysis of 3D reconstructed confocal images of RBC doublets quantifies the depletion interaction and the resulting deformation energy. Thus, we introduce a noninvasive, high-throughput platform that is generally applicable to investigate the mechanical response of biological cells to external forces and characterize their mechanical properties.
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Affiliation(s)
- Mehrnaz Babaki
- Institute of Biological Information Processing IBI-4, Forschungszentrum Jülich, Jülich, Germany; Laboratory for Soft Matter and Biophysics, KU Leuven, Leuven, Belgium
| | - Dmitry A Fedosov
- Institute of Biological Information Processing and Institute for Advanced Simulation, Forschungszentrum Jülich, Jülich, Germany
| | - Amirreza Gholivand
- Institute of Biological Information Processing IBI-4, Forschungszentrum Jülich, Jülich, Germany; Laboratory for Soft Matter and Biophysics, KU Leuven, Leuven, Belgium
| | - Joeri Opdam
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, and Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Remco Tuinier
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, and Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Minne Paul Lettinga
- Institute of Biological Information Processing IBI-4, Forschungszentrum Jülich, Jülich, Germany; Laboratory for Soft Matter and Biophysics, KU Leuven, Leuven, Belgium.
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14
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Zong W, Shao X, Li J, Chai Y, Hu X, Zhang X. Synthetic Intracellular Environments: From Basic Science to Applications. Anal Chem 2023; 95:535-549. [PMID: 36625127 DOI: 10.1021/acs.analchem.2c04199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Wei Zong
- College of Chemistry and Chemical Engineering, Qiqihar University, No. 42 Wenhua Street, Qiqihar161006, China
| | - Xiaotong Shao
- College of Chemistry and Chemical Engineering, Qiqihar University, No. 42 Wenhua Street, Qiqihar161006, China
| | - Jinlong Li
- College of Chemistry and Chemical Engineering, Qiqihar University, No. 42 Wenhua Street, Qiqihar161006, China.,Heilongjiang Provincial Key Laboratory of Catalytic Synthesis for Fine Chemicals, Qiqihar University, Qiqihar161006, China
| | - Yunhe Chai
- College of Chemistry and Chemical Engineering, Qiqihar University, No. 42 Wenhua Street, Qiqihar161006, China
| | - Xinyu Hu
- Key Laboratory of Micro-Nano Optoelectronic Devices (Wenzhou), College of Electrical and Electronic Engineering, Wenzhou University, Wenzhou325035, China
| | - Xunan Zhang
- College of Chemistry and Chemical Engineering, Qiqihar University, No. 42 Wenhua Street, Qiqihar161006, China
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15
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Armstrong FA, Cheng B, Herold RA, Megarity CF, Siritanaratkul B. From Protein Film Electrochemistry to Nanoconfined Enzyme Cascades and the Electrochemical Leaf. Chem Rev 2022; 123:5421-5458. [PMID: 36573907 PMCID: PMC10176485 DOI: 10.1021/acs.chemrev.2c00397] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Protein film electrochemistry (PFE) has given unrivalled insight into the properties of redox proteins and many electron-transferring enzymes, allowing investigations of otherwise ill-defined or intractable topics such as unstable Fe-S centers and the catalytic bias of enzymes. Many enzymes have been established to be reversible electrocatalysts when attached to an electrode, and further investigations have revealed how unusual dependences of catalytic rates on electrode potential have stark similarities with electronics. A special case, the reversible electrochemistry of a photosynthetic enzyme, ferredoxin-NADP+ reductase (FNR), loaded at very high concentrations in the 3D nanopores of a conducting metal oxide layer, is leading to a new technology that brings PFE to myriad enzymes of other classes, the activities of which become controlled by the primary electron exchange. This extension is possible because FNR-based recycling of NADP(H) can be coupled to a dehydrogenase, and thence to other enzymes linked in tandem by the tight channelling of cofactors and intermediates within the nanopores of the material. The earlier interpretations of catalytic wave-shapes and various analogies with electronics are thus extended to initiate a field perhaps aptly named "cascade-tronics", in which the flow of reactions along an enzyme cascade is monitored and controlled through an electrochemical analyzer. Unlike in photosynthesis where FNR transduces electron transfer and hydride transfer through the unidirectional recycling of NADPH, the "electrochemical leaf" (e-Leaf) can be used to drive reactions in both oxidizing and reducing directions. The e-Leaf offers a natural way to study how enzymes are affected by nanoconfinement and crowding, mimicking the physical conditions under which enzyme cascades operate in living cells. The reactions of the trapped enzymes, often at very high local concentration, are thus studied electrochemically, exploiting the potential domain to control rates and direction and the current-rate analogy to derive kinetic data. Localized NADP(H) recycling is very efficient, resulting in very high cofactor turnover numbers and new opportunities for controlling and exploiting biocatalysis.
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Affiliation(s)
- Fraser A. Armstrong
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Beichen Cheng
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Ryan A. Herold
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Clare F. Megarity
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Bhavin Siritanaratkul
- Stephenson Institute for Renewable Energy and the Department of Chemistry, University of Liverpool, Liverpool L69 7ZF, United Kingdom
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16
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Boyd-Shiwarski CR, Shiwarski DJ, Griffiths SE, Beacham RT, Norrell L, Morrison DE, Wang J, Mann J, Tennant W, Anderson EN, Franks J, Calderon M, Connolly KA, Cheema MU, Weaver CJ, Nkashama LJ, Weckerly CC, Querry KE, Pandey UB, Donnelly CJ, Sun D, Rodan AR, Subramanya AR. WNK kinases sense molecular crowding and rescue cell volume via phase separation. Cell 2022; 185:4488-4506.e20. [PMID: 36318922 PMCID: PMC9699283 DOI: 10.1016/j.cell.2022.09.042] [Citation(s) in RCA: 54] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 07/23/2022] [Accepted: 09/29/2022] [Indexed: 11/24/2022]
Abstract
When challenged by hypertonicity, dehydrated cells must recover their volume to survive. This process requires the phosphorylation-dependent regulation of SLC12 cation chloride transporters by WNK kinases, but how these kinases are activated by cell shrinkage remains unknown. Within seconds of cell exposure to hypertonicity, WNK1 concentrates into membraneless condensates, initiating a phosphorylation-dependent signal that drives net ion influx via the SLC12 cotransporters to restore cell volume. WNK1 condensate formation is driven by its intrinsically disordered C terminus, whose evolutionarily conserved signatures are necessary for efficient phase separation and volume recovery. This disorder-encoded phase behavior occurs within physiological constraints and is activated in vivo by molecular crowding rather than changes in cell size. This allows kinase activity despite an inhibitory ionic milieu and permits cell volume recovery through condensate-mediated signal amplification. Thus, WNK kinases are physiological crowding sensors that phase separate to coordinate a cell volume rescue response.
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Affiliation(s)
- Cary R Boyd-Shiwarski
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Pittsburgh Center for Kidney Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Daniel J Shiwarski
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Shawn E Griffiths
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Rebecca T Beacham
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Logan Norrell
- Molecular Medicine Program, University of Utah, Salt Lake City, UT 84132, USA
| | - Daryl E Morrison
- Molecular Medicine Program, University of Utah, Salt Lake City, UT 84132, USA
| | - Jun Wang
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Jacob Mann
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - William Tennant
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Eric N Anderson
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Jonathan Franks
- Center for Biological Imaging, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Michael Calderon
- Center for Biological Imaging, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Kelly A Connolly
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Muhammad Umar Cheema
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Claire J Weaver
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Lubika J Nkashama
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Claire C Weckerly
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Katherine E Querry
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Udai Bhan Pandey
- Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Center for Protein Conformational Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Christopher J Donnelly
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Center for Protein Conformational Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | - Dandan Sun
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; VA Pittsburgh Healthcare System, Pittsburgh, PA 15240, USA
| | - Aylin R Rodan
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84132, USA; Molecular Medicine Program, University of Utah, Salt Lake City, UT 84132, USA; Department of Internal Medicine, Division of Nephrology and Hypertension, University of Utah, Salt Lake City, UT 84132, USA; Medical Service, VA Salt Lake City Health Care System, Salt Lake City, UT 84148, USA
| | - Arohan R Subramanya
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Center for Protein Conformational Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; Pittsburgh Center for Kidney Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA; VA Pittsburgh Healthcare System, Pittsburgh, PA 15240, USA.
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17
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Molecular and environmental determinants of biomolecular condensate formation. Nat Chem Biol 2022; 18:1319-1329. [DOI: 10.1038/s41589-022-01175-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 09/15/2022] [Indexed: 11/21/2022]
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18
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van Tartwijk FW, Kaminski CF. Protein Condensation, Cellular Organization, and Spatiotemporal Regulation of Cytoplasmic Properties. Adv Biol (Weinh) 2022; 6:e2101328. [PMID: 35796197 DOI: 10.1002/adbi.202101328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 05/15/2022] [Indexed: 01/28/2023]
Abstract
The cytoplasm is an aqueous, highly crowded solution of active macromolecules. Its properties influence the behavior of proteins, including their folding, motion, and interactions. In particular, proteins in the cytoplasm can interact to form phase-separated assemblies, so-called biomolecular condensates. The interplay between cytoplasmic properties and protein condensation is critical in a number of functional contexts and is the subject of this review. The authors first describe how cytoplasmic properties can affect protein behavior, in particular condensate formation, and then describe the functional implications of this interplay in three cellular contexts, which exemplify how protein self-organization can be adapted to support certain physiological phenotypes. The authors then describe the formation of RNA-protein condensates in highly polarized cells such as neurons, where condensates play a critical role in the regulation of local protein synthesis, and describe how different stressors trigger extensive reorganization of the cytoplasm, both through signaling pathways and through direct stress-induced changes in cytoplasmic properties. Finally, the authors describe changes in protein behavior and cytoplasmic properties that may occur in extremophiles, in particular organisms that have adapted to inhabit environments of extreme temperature, and discuss the implications and functional importance of these changes.
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Affiliation(s)
- Francesca W van Tartwijk
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge, CB3 0AS, UK
| | - Clemens F Kaminski
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge, CB3 0AS, UK
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19
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Mittag T, Pappu RV. A conceptual framework for understanding phase separation and addressing open questions and challenges. Mol Cell 2022; 82:2201-2214. [PMID: 35675815 PMCID: PMC9233049 DOI: 10.1016/j.molcel.2022.05.018] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Revised: 05/04/2022] [Accepted: 05/13/2022] [Indexed: 12/11/2022]
Abstract
Macromolecular phase separation is being recognized for its potential importance and relevance as a driver of spatial organization within cells. Here, we describe a framework based on synergies between networking (percolation or gelation) and density (phase separation) transitions. Accordingly, the phase transitions in question are referred to as phase separation coupled to percolation (PSCP). The condensates that result from PSCP are viscoelastic network fluids. Such systems have sequence-, composition-, and topology-specific internal network structures that give rise to time-dependent interplays between viscous and elastic properties. Unlike pure phase separation, the process of PSCP gives rise to sequence-, chemistry-, and structure-specific distributions of clusters that can form at concentrations that lie well below the threshold concentration for phase separation. PSCP, influenced by specific versus solubility-determining interactions, also provides a bridge between different observations and helps answer questions and address challenges that have arisen regarding the role of macromolecular phase separation in biology.
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Affiliation(s)
- Tanja Mittag
- Department of Structural Biology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA.
| | - Rohit V Pappu
- Department of Biomedical Engineering and Center for Science & Engineering of Living Systems (CSELS), Washington University in St. Louis, St. Louis, MO 63130, USA.
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20
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Singh JP, Pattanayak S, Mishra S, Chakrabarti J. Effective single component description of steady state structures of passive particles in an active bath. J Chem Phys 2022; 156:214112. [DOI: 10.1063/5.0088259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We model a binary mixture of passive and active Brownian particles in two dimensions using the effective interaction between passive particles in the active bath. The activity of active particles and the size ratio of two types of particles are the two control parameters in the system. The effective interaction is calculated from the average force on two particles generated by the active particles. The effective interaction can be attractive or repulsive, depending on the system parameters. The passive particles form four distinct structural orders for different system parameters, viz., homogeneous structures, disordered cluster, ordered cluster, and crystalline structure. The change in structure is dictated by the change in nature of the effective interaction. We further confirm the four structures using a full microscopic simulation of active and passive mixture. Our study is useful to understand the different collective behavior in non-equilibrium systems.
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Affiliation(s)
- Jay Prakash Singh
- Department of Physics, Indian Institute of Technology (BHU), Varanasi 221005, India
| | - Sudipta Pattanayak
- Laboratoire de Physique Théorique et Modélisation, CNRS UMR 8089, CY Cergy Paris Université, 95302 Cergy-Pontoise, France
| | - Shradha Mishra
- Department of Physics, Indian Institute of Technology (BHU), Varanasi 221005, India
| | - Jaydeb Chakrabarti
- S. N. Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake City, Kolkata 700106, India
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21
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Opdam J, Gandhi P, Kuhnhold A, Schilling T, Tuinier R. Excluded volume interactions and phase stability in mixtures of hard spheres and hard rods. Phys Chem Chem Phys 2022; 24:11820-11827. [PMID: 35508061 DOI: 10.1039/d2cp00477a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this paper we study excluded volume interactions, the free volume fraction available, and the phase behaviour, in mixtures of hard spheres (HS) and hard rods, modeled as spherocylinders. We use free volume theory (FVT) to predict various physical properties and compare to Monte Carlo computer simulations. FVT is used at two levels. We use the original FVT approach in which it is assumed that the correlations of the HS are not affected by the rods. This is compared to a recent, more rigorous, FVT approach which includes excluded volume interactions between the different components at all levels. We find that the novel rigorous FVT approach agrees well with computer simulation results at the level of free volume available, as well as for the phase stability. The FVT predictions show significant quantitative and qualitative deviations with respect to the original FVT approach. The phase transition curves are systematically at higher rod concentrations than previously predicted. Furthermore, the calculations revealed that a certain asphericity is required to induce isostructural fluid-fluid coexistence and the stability region is highly dependent on the size ratio between the rods and the spheres.
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Affiliation(s)
- Joeri Opdam
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, & Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, P. O. Box 513, 5600 MB, Eindhoven, The Netherlands.
| | - Poshika Gandhi
- Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany.
| | - Anja Kuhnhold
- Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany.
| | - Tanja Schilling
- Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany.
| | - Remco Tuinier
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, & Institute for Complex Molecular Systems (ICMS), Eindhoven University of Technology, P. O. Box 513, 5600 MB, Eindhoven, The Netherlands.
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22
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Miyazaki K, Schweizer KS, Thirumalai D, Tuinier R, Zaccarelli E. The Asakura–Oosawa theory: Entropic forces in physics, biology, and soft matter. J Chem Phys 2022; 156:080401. [DOI: 10.1063/5.0085965] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- K. Miyazaki
- Department of Physics, Nagoya University, Nagoya 464-8602, Japan
| | - K. S. Schweizer
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA
- Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA
- Department of Materials Science, University of Illinois, Urbana, Illinois 61801, USA
| | - D. Thirumalai
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, USA
| | - R. Tuinier
- Laboratory of Physical Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
| | - E. Zaccarelli
- CNR-ISC (National Research Council–Institute for Complex Systems) and Department of Physics, Sapienza University of Rome, Rome, Italy
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23
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Nussinov R, Tsai CJ, Jang H. Signaling in the crowded cell. Curr Opin Struct Biol 2021; 71:43-50. [PMID: 34218161 PMCID: PMC8648894 DOI: 10.1016/j.sbi.2021.05.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/05/2021] [Accepted: 05/26/2021] [Indexed: 12/11/2022]
Abstract
High-resolution technologies have clarified some of the principles underlying cellular actions. However, understanding how cells receive, communicate, and respond to signals is still challenging. Questions include how efficient regulation of assemblies, which execute cell actions at the nanoscales, transmits productively at micrometer scales, especially considering the crowded environment, and how the cell organization makes it happen. Here, we describe how cells can navigate long-range diffusion-controlled signaling via association/dissociation of spatially proximal entities. Dynamic clusters can span the cell, engaging in most signaling steps. Effective local concentration, allostery, scaffolding, affinities, and the chemical and mechanical properties of the macromolecules and the environment play key roles. Signaling strength and duration matter, for example, deciding if a mutation promotes cancer or developmental syndromes.
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Affiliation(s)
- Ruth Nussinov
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, National Cancer Institute, Frederick, MD 21702, USA; Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel.
| | - Chung-Jung Tsai
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, National Cancer Institute, Frederick, MD 21702, USA
| | - Hyunbum Jang
- Computational Structural Biology Section, Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism, National Cancer Institute, Frederick, MD 21702, USA
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24
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Nassar R, Dignon GL, Razban RM, Dill KA. The Protein Folding Problem: The Role of Theory. J Mol Biol 2021; 433:167126. [PMID: 34224747 PMCID: PMC8547331 DOI: 10.1016/j.jmb.2021.167126] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/21/2021] [Accepted: 06/26/2021] [Indexed: 10/20/2022]
Abstract
The protein folding problem was first articulated as question of how order arose from disorder in proteins: How did the various native structures of proteins arise from interatomic driving forces encoded within their amino acid sequences, and how did they fold so fast? These matters have now been largely resolved by theory and statistical mechanics combined with experiments. There are general principles. Chain randomness is overcome by solvation-based codes. And in the needle-in-a-haystack metaphor, native states are found efficiently because protein haystacks (conformational ensembles) are funnel-shaped. Order-disorder theory has now grown to encompass a large swath of protein physical science across biology.
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Affiliation(s)
- Roy Nassar
- Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, NY, USA; Department of Chemistry, Stony Brook University, Stony Brook, NY, USA
| | - Gregory L Dignon
- Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, NY, USA
| | - Rostam M Razban
- Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, NY, USA
| | - Ken A Dill
- Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, NY, USA; Department of Chemistry, Stony Brook University, Stony Brook, NY, USA; Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, USA.
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25
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Rotter DAO, Heger C, Oviedo-Bocanegra LM, Graumann PL. Transcription-dependent confined diffusion of enzymes within subcellular spaces of the bacterial cytoplasm. BMC Biol 2021; 19:183. [PMID: 34474681 PMCID: PMC8414670 DOI: 10.1186/s12915-021-01083-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 07/01/2021] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Knowledge on the localization and mobility of enzymes inside bacterial cells is scarce, but important for understanding spatial regulation of metabolism. The four central enzymes (Rib enzymes) of the riboflavin (RF) biosynthesis pathway in the Gram positive model bacterium Bacillus subtilis have been studied extensively in vitro, especially the heavy RF synthase, a large protein complex with a capsid structure formed by RibH and an encapsulated RibE homotrimer, which mediates substrate-channeling. However, little is known about the behavior and mobility of these enzymes in vivo. RESULTS We have investigated the localization and diffusion of the Rib enzymes in the cytoplasm of B. subtilis. By characterizing the diffusion of Rib enzymes in live cells using single particle tracking (SPT) we provide evidence for confined diffusion at the cell poles and otherwise Brownian motion. A majority of RibH particles showed clear nucleoid occlusion and a high degree of confined motion, which is largely abolished after treatment with Rifampicin, revealing that confinement is dependent on active transcription. Contrarily, RibE is mostly diffusive within the cell, showing only 14% encapsulation by RibH nanocompartments. By localizing different diffusive populations within single cells, we find that fast diffusion occurs mostly across the nucleoids located in the cell centers, while the slower, confined subdiffusion occurs at the crowded cell poles. CONCLUSIONS Our results provide evidence for locally different motion of active enzymes within the bacterial cytoplasm, setting up metabolic compartmentalization mostly at the poles of cells.
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Affiliation(s)
- Daniel A O Rotter
- SYNMIKRO, LOEWE Center for Synthetic Microbiology, Marburg, Germany
- Department of Chemistry, Philipps-Universität Marburg, Marburg, Germany
| | - Christoph Heger
- SYNMIKRO, LOEWE Center for Synthetic Microbiology, Marburg, Germany
- Department of Chemistry, Philipps-Universität Marburg, Marburg, Germany
| | - Luis M Oviedo-Bocanegra
- SYNMIKRO, LOEWE Center for Synthetic Microbiology, Marburg, Germany
- Department of Chemistry, Philipps-Universität Marburg, Marburg, Germany
| | - Peter L Graumann
- SYNMIKRO, LOEWE Center for Synthetic Microbiology, Marburg, Germany.
- Department of Chemistry, Philipps-Universität Marburg, Marburg, Germany.
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Roles of liquid-liquid phase separation in bacterial RNA metabolism. Curr Opin Microbiol 2021; 61:91-98. [PMID: 33878678 DOI: 10.1016/j.mib.2021.03.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 03/24/2021] [Accepted: 03/26/2021] [Indexed: 01/01/2023]
Abstract
While bacteria typically lack membrane bound organelles, the mechanisms of subcellular organization have been unclear. Bacteria have recently been found to harbor membraneless organelles containing enzymes of many biochemical pathways. These organelles, called biomolecular condensates, have been found to commonly form through the process of liquid-liquid phase separation and are typically enriched in nucleic acid binding proteins. Interestingly, eukaryote and bacterial transcription and RNA decay machinery have been found to form biomolecular condensates. Additionally, DEAD Box ATPases from eukaryotes and bacteria have also been found to modulate biomolecular condensates. The shared ability of RNA metabolic enzymes to assemble into biomolecular condensates across domains suggests that this mode of subcellular organization aids in the control of RNA metabolism.
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27
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Jang S, Xuan Z, Lagoy RC, Jawerth LM, Gonzalez IJ, Singh M, Prashad S, Kim HS, Patel A, Albrecht DR, Hyman AA, Colón-Ramos DA. Phosphofructokinase relocalizes into subcellular compartments with liquid-like properties in vivo. Biophys J 2021; 120:1170-1186. [PMID: 32853565 PMCID: PMC8059094 DOI: 10.1016/j.bpj.2020.08.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/31/2020] [Accepted: 08/05/2020] [Indexed: 02/08/2023] Open
Abstract
Although much is known about the biochemical regulation of glycolytic enzymes, less is understood about how they are organized inside cells. We systematically examine the dynamic subcellular localization of glycolytic protein phosphofructokinase-1/PFK-1.1 in Caenorhabditis elegans. We determine that endogenous PFK-1.1 localizes to subcellular compartments in vivo. In neurons, PFK-1.1 forms phase-separated condensates near synapses in response to energy stress from transient hypoxia. Restoring animals to normoxic conditions results in cytosolic dispersion of PFK-1.1. PFK-1.1 condensates exhibit liquid-like properties, including spheroid shapes due to surface tension, fluidity due to deformations, and fast internal molecular rearrangements. Heterologous self-association domain cryptochrome 2 promotes formation of PFK-1.1 condensates and recruitment of aldolase/ALDO-1. PFK-1.1 condensates do not correspond to stress granules and might represent novel metabolic subcompartments. Our studies indicate that glycolytic protein PFK-1.1 can dynamically form condensates in vivo.
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Affiliation(s)
- SoRi Jang
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut
| | - Zhao Xuan
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut
| | - Ross C Lagoy
- Department of Biomedical Engineering and Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts
| | - Louise M Jawerth
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Ian J Gonzalez
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut
| | - Milind Singh
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut
| | - Shavanie Prashad
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut
| | - Hee Soo Kim
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut
| | - Avinash Patel
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Dirk R Albrecht
- Department of Biomedical Engineering and Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, Massachusetts
| | - Anthony A Hyman
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Daniel A Colón-Ramos
- Department of Neuroscience and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut; Instituto de Neurobiología, Universidad de Puerto Rico, San Juan, Puerto Rico.
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28
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King JT, Shakya A. Phase separation of DNA: From past to present. Biophys J 2021; 120:1139-1149. [PMID: 33582138 PMCID: PMC8059212 DOI: 10.1016/j.bpj.2021.01.033] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 01/11/2021] [Accepted: 01/22/2021] [Indexed: 02/08/2023] Open
Abstract
Phase separation of biological molecules, such as nucleic acids and proteins, has garnered widespread attention across many fields in recent years. For instance, liquid-liquid phase separation has been implicated not only in membraneless intracellular organization but also in many biochemical processes, including transcription, translation, and cellular signaling. Here, we present a historical background of biological phase separation and survey current work on nuclear organization and its connection to DNA phase separation from the perspective of DNA sequence, structure, and genomic context.
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Affiliation(s)
- John T King
- Center for Soft and Living Matter, Institute for Basic Science, Ulsan, Republic of Korea.
| | - Anisha Shakya
- Center for Soft and Living Matter, Institute for Basic Science, Ulsan, Republic of Korea.
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Matsumoto S, Sugimoto N. New Insights into the Functions of Nucleic Acids Controlled by Cellular Microenvironments. Top Curr Chem (Cham) 2021; 379:17. [PMID: 33782792 DOI: 10.1007/s41061-021-00329-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 03/11/2021] [Indexed: 12/11/2022]
Abstract
The right-handed double-helical B-form structure (B-form duplex) has been widely recognized as the canonical structure of nucleic acids since it was first proposed by James Watson and Francis Crick in 1953. This B-form duplex model has a monochronic and static structure and codes genetic information within a sequence. Interestingly, DNA and RNA can form various non-canonical structures, such as hairpin loops, left-handed helices, triplexes, tetraplexes of G-quadruplex and i-motif, and branched junctions, in addition to the canonical structure. The formation of non-canonical structures depends not only on sequence but also on the surrounding environment. Importantly, these non-canonical structures may exhibit a wide variety of biological roles by changing their structures and stabilities in response to the surrounding environments, which undergo vast changes at specific locations and at specific times in cells. Here, we review recent progress regarding the interesting behaviors and functions of nucleic acids controlled by molecularly crowded cellular conditions. New insights gained from recent studies suggest that nucleic acids not only code genetic information in sequences but also have unknown functions regarding their structures and stabilities through drastic structural changes in cellular environments.
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Affiliation(s)
- Saki Matsumoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-Minamimachi, Kobe, 650-0047, Japan
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-Minamimachi, Kobe, 650-0047, Japan. .,Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 Minatojima-Minamimachi, Kobe, 650-0047, Japan.
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30
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Farahi N, Lazar T, Wodak SJ, Tompa P, Pancsa R. Integration of Data from Liquid-Liquid Phase Separation Databases Highlights Concentration and Dosage Sensitivity of LLPS Drivers. Int J Mol Sci 2021; 22:ijms22063017. [PMID: 33809541 PMCID: PMC8002189 DOI: 10.3390/ijms22063017] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 12/13/2022] Open
Abstract
Liquid–liquid phase separation (LLPS) is a molecular process that leads to the formation of membraneless organelles, representing functionally specialized liquid-like cellular condensates formed by proteins and nucleic acids. Integrating the data on LLPS-associated proteins from dedicated databases revealed only modest agreement between them and yielded a high-confidence dataset of 89 human LLPS drivers. Analysis of the supporting evidence for our dataset uncovered a systematic and potentially concerning difference between protein concentrations used in a good fraction of the in vitro LLPS experiments, a key parameter that governs the phase behavior, and the proteomics-derived cellular abundance levels of the corresponding proteins. Closer scrutiny of the underlying experimental data enabled us to offer a sound rationale for this systematic difference, which draws on our current understanding of the cellular organization of the proteome and the LLPS process. In support of this rationale, we find that genes coding for our human LLPS drivers tend to be dosage-sensitive, suggesting that their cellular availability is tightly regulated to preserve their functional role in direct or indirect relation to condensate formation. Our analysis offers guideposts for increasing agreement between in vitro and in vivo studies, probing the roles of proteins in LLPS.
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Affiliation(s)
- Nazanin Farahi
- VIB-VUB Center for Structural Biology, Flemish Institute for Biotechnology, 1050 Brussels, Belgium; (N.F.); (T.L.); (S.J.W.)
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium
- Department of Biology, Technical University of Kaiserslautern, 67663 Kaiserslautern, Germany
| | - Tamas Lazar
- VIB-VUB Center for Structural Biology, Flemish Institute for Biotechnology, 1050 Brussels, Belgium; (N.F.); (T.L.); (S.J.W.)
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium
| | - Shoshana J. Wodak
- VIB-VUB Center for Structural Biology, Flemish Institute for Biotechnology, 1050 Brussels, Belgium; (N.F.); (T.L.); (S.J.W.)
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium
| | - Peter Tompa
- VIB-VUB Center for Structural Biology, Flemish Institute for Biotechnology, 1050 Brussels, Belgium; (N.F.); (T.L.); (S.J.W.)
- Structural Biology Brussels, Vrije Universiteit Brussel, 1050 Brussels, Belgium
- Institute of Enzymology, Research Centre for Natural Sciences, 1117 Budapest, Hungary
- Correspondence: (P.T.); (R.P.)
| | - Rita Pancsa
- Institute of Enzymology, Research Centre for Natural Sciences, 1117 Budapest, Hungary
- Correspondence: (P.T.); (R.P.)
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31
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Wilcox XE, Chung CB, Slade KM. Macromolecular crowding effects on the kinetics of opposing reactions catalyzed by alcohol dehydrogenase. Biochem Biophys Rep 2021; 26:100956. [PMID: 33665382 PMCID: PMC7905371 DOI: 10.1016/j.bbrep.2021.100956] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 01/03/2021] [Accepted: 02/09/2021] [Indexed: 12/01/2022] Open
Abstract
In order to better understand how the complex, densely packed, heterogeneous milieu of a cell influences enzyme kinetics, we exposed opposing reactions catalyzed by yeast alcohol dehydrogenase (YADH) to both synthetic and protein crowders ranging from 10 to 550 kDa. The results reveal that the effects from macromolecular crowding depend on the direction of the reaction. The presence of the synthetic polymers, Ficoll and dextran, decrease Vmax and Km for ethanol oxidation. In contrast, these crowders have little effect or even increase these kinetic parameters for acetaldehyde reduction. This increase in Vmax is likely due to excluded volume effects, which are partially counteracted by viscosity hindering release of the NAD+ product. Macromolecular crowding is further complicated by the presence of a depletion layer in solutions of dextran larger than YADH, which diminishes the hindrance from viscosity. The disparate effects from 25 g/L dextran or glucose compared to 25 g/L Ficoll or sucrose reveals that soft interactions must also be considered. Data from binary mixtures of glucose, dextran, and Ficoll support this “tuning” of opposing factors. While macromolecular crowding was originally proposed to influence proteins mainly through excluded volume effects, this work compliments the growing body of evidence revealing that other factors, such as preferential hydration, chemical interactions, and the presence of a depletion layer also contribute to the overall effect of crowding. Yeast alcohol dehydrogenase reduction of acetaldehyde is enhanced by crowding. Crowding effects on YADH kinetics depend on the direction of the reaction. Crowders like dextran can be used as a tool to elucidate enzyme mechanism. Excluded volume optimizes YADH hydride transfer; viscosity hinders product release. The presence of a depletion layer with large crowders mitigates their effects.
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Affiliation(s)
- Xander E Wilcox
- Department of Chemistry, University of California at Davis, CA, 95616, USA
| | - Charmaine B Chung
- Department of Chemistry, Hobart and William Smith Colleges, 300 Pulteney St, Geneva, NY, 14456, USA
| | - Kristin M Slade
- Department of Chemistry, Hobart and William Smith Colleges, 300 Pulteney St, Geneva, NY, 14456, USA
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32
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Mussel M, Basser PJ, Horkay F. Ion-Induced Volume Transition in Gels and Its Role in Biology. Gels 2021; 7:20. [PMID: 33670826 PMCID: PMC8005988 DOI: 10.3390/gels7010020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 02/09/2021] [Accepted: 02/11/2021] [Indexed: 12/12/2022] Open
Abstract
Incremental changes in ionic composition, solvent quality, and temperature can lead to reversible and abrupt structural changes in many synthetic and biopolymer systems. In the biological milieu, this nonlinear response is believed to play an important functional role in various biological systems, including DNA condensation, cell secretion, water flow in xylem of plants, cell resting potential, and formation of membraneless organelles. While these systems are markedly different from one another, a physicochemical framework that treats them as polyelectrolytes, provides a means to interpret experimental results and make in silico predictions. This article summarizes experimental results made on ion-induced volume phase transition in a polyelectrolyte model gel (sodium polyacrylate) and observations on the above-mentioned biological systems indicating the existence of a steep response.
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Affiliation(s)
- Matan Mussel
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA;
| | | | - Ferenc Horkay
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA;
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33
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Harrison RES, Weng K, Wang Y, Peng Q. Phase Separation and Histone Epigenetics in Genome Regulation. CURRENT OPINION IN SOLID STATE & MATERIALS SCIENCE 2021; 25:100892. [PMID: 33519290 PMCID: PMC7845916 DOI: 10.1016/j.cossms.2020.100892] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Liquid-liquid phase separation is increasingly recognized as a phenomenon that affects cell behavior. For example, phase separation of transcription factors and coactivators has been shown to drive efficient transcription. For many years, phase separation of intracellular components has been observed; however, only recently have researchers been able to garner functional significance from such events. Inspired from recent literature that describes phase separation of chromatin in a histone-dependent manner, we review the role and effect of phase separation and histone epigenetics in regulating the genome and discuss how these phenomena can be leveraged to control cell behavior.
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Affiliation(s)
- Reed E. S. Harrison
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
- Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kegui Weng
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
- Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA 92093, USA
- Chongqing University Cancer Hospital & Chongqing Cancer Institute & Chongqing Cancer Hospital, Chongqing, 400044, P. R. China
| | - Yingxiao Wang
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
- Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Qin Peng
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
- Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA 92093, USA
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34
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Wetting regulates autophagy of phase-separated compartments and the cytosol. Nature 2021; 591:142-146. [DOI: 10.1038/s41586-020-2992-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 09/28/2020] [Indexed: 01/19/2023]
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35
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Jalihal AP, Schmidt A, Gao G, Little SR, Pitchiaya S, Walter NG. Hyperosmotic phase separation: Condensates beyond inclusions, granules and organelles. J Biol Chem 2021; 296:100044. [PMID: 33168632 PMCID: PMC7948973 DOI: 10.1074/jbc.rev120.010899] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 11/06/2020] [Accepted: 11/09/2020] [Indexed: 01/09/2023] Open
Abstract
Biological liquid-liquid phase separation has gained considerable attention in recent years as a driving force for the assembly of subcellular compartments termed membraneless organelles. The field has made great strides in elucidating the molecular basis of biomolecular phase separation in various disease, stress response, and developmental contexts. Many important biological consequences of such "condensation" are now emerging from in vivo studies. Here we review recent work from our group and others showing that many proteins undergo rapid, reversible condensation in the cellular response to ubiquitous environmental fluctuations such as osmotic changes. We discuss molecular crowding as an important driver of condensation in these responses and suggest that a significant fraction of the proteome is poised to undergo phase separation under physiological conditions. In addition, we review methods currently emerging to visualize, quantify, and modulate the dynamics of intracellular condensates in live cells. Finally, we propose a metaphor for rapid phase separation based on cloud formation, reasoning that our familiar experiences with the readily reversible condensation of water droplets help understand the principle of phase separation. Overall, we provide an account of how biological phase separation supports the highly intertwined relationship between the composition and dynamic internal organization of cells, thus facilitating extremely rapid reorganization in response to internal and external fluctuations.
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Affiliation(s)
- Ameya P Jalihal
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA; Cell and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Andreas Schmidt
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - Guoming Gao
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA; Biophysics Graduate Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Saffron R Little
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA; Program in Chemical Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Sethuramasundaram Pitchiaya
- Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, Michigan, USA; Department of Pathology, University of Michigan, Ann Arbor, Michigan, USA
| | - Nils G Walter
- Single Molecule Analysis Group and Center for RNA Biomedicine, Department of Chemistry, University of Michigan, Ann Arbor, Michigan, USA.
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Sankaranarayanan M, Weil TT. Granule regulation by phase separation during Drosophila oogenesis. Emerg Top Life Sci 2020; 4:343-352. [PMID: 32573699 PMCID: PMC7733668 DOI: 10.1042/etls20190155] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/29/2020] [Accepted: 06/02/2020] [Indexed: 12/13/2022]
Abstract
Drosophila eggs are highly polarised cells that use RNA-protein complexes to regulate storage and translational control of maternal RNAs. Ribonucleoprotein granules are a class of biological condensates that form predominantly by intracellular phase separation. Despite extensive in vitro studies testing the physical principles regulating condensates, how phase separation translates to biological function remains largely unanswered. In this perspective, we discuss granules in Drosophila oogenesis as a model system for investigating the physiological role of phase separation. We review key maternal granules and their properties while highlighting ribonucleoprotein phase separation behaviours observed during development. Finally, we discuss how concepts and models from liquid-liquid phase separation could be used to test mechanisms underlying granule assembly, regulation and function in Drosophila oogenesis.
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Affiliation(s)
- M Sankaranarayanan
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, U.K
| | - Timothy T Weil
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, U.K
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37
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Sakuta H, Fujita F, Hamada T, Hayashi M, Takiguchi K, Tsumoto K, Yoshikawa K. Self-Emergent Protocells Generated in an Aqueous Solution with Binary Macromolecules through Liquid-Liquid Phase Separation. Chembiochem 2020; 21:3323-3328. [PMID: 32667694 PMCID: PMC7754443 DOI: 10.1002/cbic.202000344] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/09/2020] [Indexed: 12/18/2022]
Abstract
Recently, liquid-liquid phase separation (LLPS) has attracted considerable attention among researchers in the life sciences as a plausible mechanism for the generation of microstructures inside cells. LLPS occurs through multiple nonspecific interactions and does not always require a lock-and-key interaction with a binary macromolecular solution. The remarkable features of LLPS include the non-uniform localization and concentration of solutes, resulting in the ability to isolate certain chemical systems and thereby parallelize multiple chemical reactions within the limited space of a living cell. We report that, by using the macromolecules, poly(ethylene glycol) (PEG) and dextran, that exhibit LLPS in an aqueous solution, cell-sized liposomes are spontaneously formed therein in the presence of phospholipids. In this system, LLPS is generated through the depletion effect of macromolecules. The results showed that cell-like microdroplets entrapping DNA wrapped by a phospholipid layer emerge in a self-organized manner.
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Affiliation(s)
- Hiroki Sakuta
- Graduate School of Life and Medical SciencesDoshisha UniversityTataramiyakodani 1–3Kyotanabe, Kyoto610-0394Japan
| | - Fumika Fujita
- Graduate School of Life and Medical SciencesDoshisha UniversityTataramiyakodani 1–3Kyotanabe, Kyoto610-0394Japan
| | - Tsutomu Hamada
- School of Materials ScienceJapan Advanced Institute of Science and TechnologyNomi, Ishikawa923-1292Japan
| | - Masahito Hayashi
- Department of Frontier BioscienceHosei UniversityKoganei, Tokyo184-8584Japan
| | - Kingo Takiguchi
- Graduate School of ScienceNagoya University Furo-cho, Chikusa-kuNagoya, Aichi464-8602Japan
| | - Kanta Tsumoto
- Division of Chemistry for Materials Graduate School of EngineeringMie UniversityKurimamachiya-cho 1577Tsu, Mie514-8507Japan
| | - Kenichi Yoshikawa
- Graduate School of Life and Medical SciencesDoshisha UniversityTataramiyakodani 1–3Kyotanabe, Kyoto610-0394Japan
- Center for Integrative Medicine and PhysicsInstitute for Advanced StudyKyoto UniversityKyoto606-8501Japan
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Lira RB, Willersinn J, Schmidt BVKJ, Dimova R. Selective Partitioning of (Biomacro)molecules in the Crowded Environment of Double-Hydrophilic Block Copolymers. Macromolecules 2020. [DOI: 10.1021/acs.macromol.0c01839] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Rafael B. Lira
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
- Moleculaire Biofysica, Zernike Instituut, Rijksuniversiteit Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Jochen Willersinn
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| | - Bernhard V. K. J. Schmidt
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
- School of Chemistry, University of Glasgow, G128QQ Glasgow, U.K
| | - Rumiana Dimova
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
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Jalihal AP, Pitchiaya S, Xiao L, Bawa P, Jiang X, Bedi K, Parolia A, Cieslik M, Ljungman M, Chinnaiyan AM, Walter NG. Multivalent Proteins Rapidly and Reversibly Phase-Separate upon Osmotic Cell Volume Change. Mol Cell 2020; 79:978-990.e5. [PMID: 32857953 PMCID: PMC7502480 DOI: 10.1016/j.molcel.2020.08.004] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 06/11/2020] [Accepted: 08/05/2020] [Indexed: 12/12/2022]
Abstract
Processing bodies (PBs) and stress granules (SGs) are prominent examples of subcellular, membraneless compartments that are observed under physiological and stress conditions, respectively. We observe that the trimeric PB protein DCP1A rapidly (within ∼10 s) phase-separates in mammalian cells during hyperosmotic stress and dissolves upon isosmotic rescue (over ∼100 s) with minimal effect on cell viability even after multiple cycles of osmotic perturbation. Strikingly, this rapid intracellular hyperosmotic phase separation (HOPS) correlates with the degree of cell volume compression, distinct from SG assembly, and is exhibited broadly by homo-multimeric (valency ≥ 2) proteins across several cell types. Notably, HOPS sequesters pre-mRNA cleavage factor components from actively transcribing genomic loci, providing a mechanism for hyperosmolarity-induced global impairment of transcription termination. Our data suggest that the multimeric proteome rapidly responds to changes in hydration and molecular crowding, revealing an unexpected mode of globally programmed phase separation and sequestration.
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Affiliation(s)
- Ameya P Jalihal
- Single Molecule Analysis Group, Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA; Cell and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sethuramasundaram Pitchiaya
- Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, MI 48109-1055, USA; Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA; Center for RNA Biomedicine, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Lanbo Xiao
- Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, MI 48109-1055, USA; Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Pushpinder Bawa
- Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, MI 48109-1055, USA
| | - Xia Jiang
- Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, MI 48109-1055, USA
| | - Karan Bedi
- Department of Radiation Oncology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Abhijit Parolia
- Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, MI 48109-1055, USA; Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Marcin Cieslik
- Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, MI 48109-1055, USA; Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Mats Ljungman
- Department of Radiation Oncology, University of Michigan, Ann Arbor, MI 48109, USA; Rogel Cancer Center, University of Michigan, Ann Arbor, MI 48109, USA; Center for RNA Biomedicine, University of Michigan, Ann Arbor, MI 48109, USA; Department of Environmental Health Sciences, University of Michigan, Ann Arbor, MI 48109, USA
| | - Arul M Chinnaiyan
- Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, MI 48109-1055, USA; Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA; Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI 48109, USA; Department of Urology, University of Michigan, Ann Arbor, MI 48109, USA; Rogel Cancer Center, University of Michigan, Ann Arbor, MI 48109, USA; Center for RNA Biomedicine, University of Michigan, Ann Arbor, MI 48109, USA.
| | - Nils G Walter
- Single Molecule Analysis Group, Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA; Rogel Cancer Center, University of Michigan, Ann Arbor, MI 48109, USA; Center for RNA Biomedicine, University of Michigan, Ann Arbor, MI 48109, USA.
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Adame-Arana O, Weber CA, Zaburdaev V, Prost J, Jülicher F. Liquid Phase Separation Controlled by pH. Biophys J 2020; 119:1590-1605. [PMID: 33010236 DOI: 10.1016/j.bpj.2020.07.044] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 06/27/2020] [Accepted: 07/06/2020] [Indexed: 12/31/2022] Open
Abstract
We present a minimal model to study the effects of pH on liquid phase separation of macromolecules. Our model describes a mixture composed of water and macromolecules that exist in three different charge states and have a tendency to phase separate. This phase separation is affected by pH via a set of chemical reactions describing protonation and deprotonation of macromolecules, as well as self-ionization of water. We consider the simple case in which interactions are captured by Flory-Huggins interaction parameters corresponding to Debye screening lengths shorter than a nanometer, which is relevant to proteins inside biological cells under physiological conditions. We identify the conjugate thermodynamic variables at chemical equilibrium and discuss the effective free energy at fixed pH. First, we study phase diagrams as a function of macromolecule concentration and temperature at the isoelectric point of the macromolecules. We find a rich variety of phase diagram topologies, including multiple critical points, triple points, and first-order transition points. Second, we change the pH relative to the isoelectric point of the macromolecules and study how phase diagrams depend on pH. We find that these phase diagrams as a function of pH strongly depend on whether oppositely charged macromolecules or neutral macromolecules have a stronger tendency to phase separate. One key finding is that we predict the existence of a reentrant behavior as a function of pH. In addition, our model predicts that the region of phase separation is typically broader at the isoelectric point. This model could account for both in vitro phase separation of proteins as a function of pH and protein phase separation in yeast cells for pH values close to the isoelectric point of many cytosolic proteins.
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Affiliation(s)
- Omar Adame-Arana
- Max-Planck-Institut für Physik komplexer Systeme, Dresden, Germany
| | - Christoph A Weber
- Max-Planck-Institut für Physik komplexer Systeme, Dresden, Germany; Center for Systems Biology Dresden, Dresden, Germany
| | - Vasily Zaburdaev
- Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, Erlangen, Germany
| | - Jacques Prost
- Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, CNRS UMR168, Paris, France; Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Frank Jülicher
- Max-Planck-Institut für Physik komplexer Systeme, Dresden, Germany; Center for Systems Biology Dresden, Dresden, Germany; Cluster of Excellence Physics of Life, Technische Universität Dresden, Dresden, Germany.
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41
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Trivedi P, Stukenberg PT. A Condensed View of the Chromosome Passenger Complex. Trends Cell Biol 2020; 30:676-687. [PMID: 32684321 PMCID: PMC10714244 DOI: 10.1016/j.tcb.2020.06.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 06/12/2020] [Accepted: 06/15/2020] [Indexed: 02/02/2023]
Abstract
The inner centromere is a region on the mitotic chromosome that serves as a platform for mitotic signaling and possesses unique biophysical properties that enable it to withstand relatively large pulling forces that are generated by kinetochores (KTs) during chromosome segregation. The chromosomal passenger complex (CPC) localizes to and is the key regulator of inner centromere organization and function during mitosis. Recently, we demonstrated that in addition to its kinase and histone code-reading activities, the CPC also can undergo liquid-liquid phase separation (LLPS) and proposed that the inner centromere is a membraneless organelle scaffolded by the CPC. In this perspective, we explore mechanisms that can allow the formation and dissolution of this membraneless body. The cell-cycle-regulated spatially defined assembly and disassembly of the CPC condensate at the inner centromere can reveal general principles about how histone modifications control chromatin-bound membraneless organelles. We further explore how the ability of the CPC to undergo LLPS may contribute to the organization and function of the inner centromere during mitosis.
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Affiliation(s)
- Prasad Trivedi
- Department of Cell Biology, University of Virginia, School of Medicine, Charlottesville, VA, USA; Department of Biochemistry and Molecular Genetics, University of Virginia, School of Medicine, Charlottesville, VA, USA
| | - P Todd Stukenberg
- Department of Cell Biology, University of Virginia, School of Medicine, Charlottesville, VA, USA; Department of Biochemistry and Molecular Genetics, University of Virginia, School of Medicine, Charlottesville, VA, USA.
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42
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Lietha D, Izard T. Roles of Membrane Domains in Integrin-Mediated Cell Adhesion. Int J Mol Sci 2020; 21:ijms21155531. [PMID: 32752284 PMCID: PMC7432473 DOI: 10.3390/ijms21155531] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/29/2020] [Accepted: 07/31/2020] [Indexed: 12/13/2022] Open
Abstract
The composition and organization of the plasma membrane play important functional and regulatory roles in integrin signaling, which direct many physiological and pathological processes, such as development, wound healing, immunity, thrombosis, and cancer metastasis. Membranes are comprised of regions that are thick or thin owing to spontaneous partitioning of long-chain saturated lipids from short-chain polyunsaturated lipids into domains defined as ordered and liquid-disorder domains, respectively. Liquid-ordered domains are typically 100 nm in diameter and sometimes referred to as lipid rafts. We posit that integrin β senses membrane thickness and that mechanical force on the membrane regulates integrin activation through membrane thinning. This review examines what we know about the nature and mechanism of the interaction of integrins with the plasma membrane and its effects on regulating integrins and its binding partners.
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Affiliation(s)
- Daniel Lietha
- Cell Signaling and Adhesion Group, Structural and Chemical Biology, Margarita Salas Center for Biological Research (CIB-CSIC), E-28040 Madrid, Spain;
| | - Tina Izard
- Cell Adhesion Laboratory, Department of Integrative Structural and Computational Biology, The Scripps Research Institute, Jupiter, FL 33458, USA
- Correspondence:
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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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Ma Q, Song Y, Sun W, Cao J, Yuan H, Wang X, Sun Y, Shum HC. Cell-Inspired All-Aqueous Microfluidics: From Intracellular Liquid-Liquid Phase Separation toward Advanced Biomaterials. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:1903359. [PMID: 32274317 PMCID: PMC7141073 DOI: 10.1002/advs.201903359] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 01/06/2020] [Indexed: 05/24/2023]
Abstract
Living cells have evolved over billions of years to develop structural and functional complexity with numerous intracellular compartments that are formed due to liquid-liquid phase separation (LLPS). Discovery of the amazing and vital roles of cells in life has sparked tremendous efforts to investigate and replicate the intracellular LLPS. Among them, all-aqueous emulsions are a minimalistic liquid model that recapitulates the structural and functional features of membraneless organelles and protocells. Here, an emerging all-aqueous microfluidic technology derived from micrometer-scaled manipulation of LLPS is presented; the technology enables the state-of-art design of advanced biomaterials with exquisite structural proficiency and diversified biological functions. Moreover, a variety of emerging biomedical applications, including encapsulation and delivery of bioactive gradients, fabrication of artificial membraneless organelles, as well as printing and assembly of predesigned cell patterns and living tissues, are inspired by their cellular counterparts. Finally, the challenges and perspectives for further advancing the cell-inspired all-aqueous microfluidics toward a more powerful and versatile platform are discussed, particularly regarding new opportunities in multidisciplinary fundamental research and biomedical applications.
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Affiliation(s)
- Qingming Ma
- Department of PharmaceuticsSchool of PharmacyQingdao UniversityQingdao266021China
| | - Yang Song
- Wallace H Coulter Department of Biomedical EngineeringGeorgia Institute of Technology & Emory School of MedicineAtlantaGA30332USA
| | - Wentao Sun
- Center for Basic Medical ResearchTEDA International Cardiovascular HospitalChinese Academy of Medical Sciences & Peking Union Medical CollegeTianjin300457China
| | - Jie Cao
- Department of PharmaceuticsSchool of PharmacyQingdao UniversityQingdao266021China
| | - Hao Yuan
- Institute of Applied MechanicsNational Taiwan UniversityTaipei10617Taiwan
| | - Xinyu Wang
- Institute of Thermal Science and TechnologyShandong UniversityJinan250061China
| | - Yong Sun
- Department of PharmaceuticsSchool of PharmacyQingdao UniversityQingdao266021China
| | - Ho Cheung Shum
- Department of Mechanical EngineeringUniversity of Hong KongPokfulam RoadHong Kong
- HKU‐Shenzhen Institute of Research and Innovation (HKU‐SIRI)Shenzhen518000China
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45
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Abstract
Liquid-liquid phase separation plays an important role in cellular organization. Many subcellular condensed bodies are hierarchically organized into multiple coexisting domains or layers. However, our molecular understanding of the assembly and internal organization of these multicomponent droplets is still incomplete, and rules for the coexistence of condensed phases are lacking. Here, we show that the formation of hierarchically organized multiphase droplets with up to three coexisting layers is a generic phenomenon in mixtures of complex coacervates, which serve as models of charge-driven liquid-liquid phase separated systems. We present simple theoretical guidelines to explain both the hierarchical arrangement and the demixing transition in multiphase droplets using the interfacial tensions and critical salt concentration as inputs. Multiple coacervates can coexist if they differ sufficiently in macromolecular density, and we show that the associated differences in critical salt concentration can be used to predict multiphase droplet formation. We also show that the coexisting coacervates present distinct chemical environments that can concentrate guest molecules to different extents. Our findings suggest that condensate immiscibility may be a very general feature in biological systems, which could be exploited to design self-organized synthetic compartments to control biomolecular processes.
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Affiliation(s)
- Tiemei Lu
- Institute for Molecules and
Materials, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Evan Spruijt
- Institute for Molecules and
Materials, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
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Jeyhani M, Thevakumaran R, Abbasi N, Hwang DK, Tsai SSH. Microfluidic Generation of All-Aqueous Double and Triple Emulsions. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e1906565. [PMID: 31985166 DOI: 10.1002/smll.201906565] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 01/07/2020] [Indexed: 05/22/2023]
Abstract
Higher order emulsions are used in a variety of different applications in biomedicine, biological studies, cosmetics, and the food industry. Conventional droplet generation platforms for making higher order emulsions use organic solvents as the continuous phase, which is not biocompatible and as a result, further washing steps are required to remove the toxic continuous phase. Recently, droplet generation based on aqueous two-phase systems (ATPS) has emerged in the field of droplet microfluidics due to their intrinsic biocompatibility. Here, a platform to generate all-aqueous double and triple emulsions by introducing pressure-driven flows inside a microfluidic hybrid device is presented. This system uses a conventional microfluidic flow-focusing geometry coupled with a coaxial microneedle and a glass capillary embedded in flow-focusing junctions. The configuration of the hybrid device enables the focusing of two coaxial two-phase streams, which helps to avoid commonly observed channel-wetting problems. It is shown that this approach achieves the fabrication of higher-order emulsions in a poly(dimethylsiloxane)-based microfluidic device, and controls the structure of the all-aqueous emulsions. This hybrid microfluidic approach allows for facile higher-order biocompatible emulsion formation, and it is anticipated that this platform will find utility for generating biocompatible materials for various biotechnological applications.
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Affiliation(s)
- Morteza Jeyhani
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, ON, M5B 2K3, Canada
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, M5B 1W8, Canada
- Institute for Biomedical Engineering, Science and Technology (iBEST)-a Partnership between Ryerson University and St. Michael's Hospital, Toronto, ON, M5B 1T8, Canada
| | - Risavarshni Thevakumaran
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, M5B 1W8, Canada
- Institute for Biomedical Engineering, Science and Technology (iBEST)-a Partnership between Ryerson University and St. Michael's Hospital, Toronto, ON, M5B 1T8, Canada
- Department of Electrical, Computer and Biomedical Engineering, Ryerson University, Toronto, ON, M5B 2K3, Canada
| | - Niki Abbasi
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, ON, M5B 2K3, Canada
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, M5B 1W8, Canada
- Institute for Biomedical Engineering, Science and Technology (iBEST)-a Partnership between Ryerson University and St. Michael's Hospital, Toronto, ON, M5B 1T8, Canada
| | - Dae Kun Hwang
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, M5B 1W8, Canada
- Institute for Biomedical Engineering, Science and Technology (iBEST)-a Partnership between Ryerson University and St. Michael's Hospital, Toronto, ON, M5B 1T8, Canada
- Department of Chemical Engineering, Ryerson University, Toronto, ON, M5B 2K3, Canada
| | - Scott S H Tsai
- Department of Mechanical and Industrial Engineering, Ryerson University, Toronto, ON, M5B 2K3, Canada
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, M5B 1W8, Canada
- Institute for Biomedical Engineering, Science and Technology (iBEST)-a Partnership between Ryerson University and St. Michael's Hospital, Toronto, ON, M5B 1T8, Canada
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Bridging biophysics and neurology: aberrant phase transitions in neurodegenerative disease. Nat Rev Neurol 2020; 15:272-286. [PMID: 30890779 DOI: 10.1038/s41582-019-0157-5] [Citation(s) in RCA: 123] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Biomolecular condensation arising through phase transitions has emerged as an essential organizational strategy that governs many aspects of cell biology. In particular, the role of phase transitions in the assembly of large, complex ribonucleoprotein (RNP) granules has become appreciated as an important regulator of RNA metabolism. In parallel, genetic, histopathological and cell and molecular studies have provided evidence that disturbance of phase transitions is an important driver of neurological diseases, notably amyotrophic lateral sclerosis (ALS), but most likely also other diseases. Indeed, our growing knowledge of the biophysics underlying biological phase transitions suggests that this process offers a unifying mechanism to explain the numerous and diverse disturbances in RNA metabolism that have been observed in ALS and some related diseases - specifically, that these diseases are driven by disturbances in the material properties of RNP granules. Here, we review the evidence for this hypothesis, emphasizing the reciprocal roles in which disease-related protein and disease-related RNA can lead to disturbances in the material properties of RNP granules and consequent pathogenesis. Additionally, we review evidence that implicates aberrant phase transitions as a contributing factor to a larger set of neurodegenerative diseases, including frontotemporal dementia, certain repeat expansion diseases and Alzheimer disease.
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48
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Das N, Sen P. Size-dependent macromolecular crowding effect on the thermodynamics of protein unfolding revealed at the single molecular level. Int J Biol Macromol 2019; 141:843-854. [DOI: 10.1016/j.ijbiomac.2019.09.029] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/30/2019] [Accepted: 09/04/2019] [Indexed: 11/29/2022]
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Abstract
Recent advances suggest that the response of RNA metabolism to stress has an important role in the pathophysiology of neurodegenerative diseases, particularly amyotrophic lateral sclerosis, frontotemporal dementias and Alzheimer disease. RNA-binding proteins (RBPs) control the utilization of mRNA during stress, in part through the formation of membraneless organelles termed stress granules (SGs). These structures form through a process of liquid-liquid phase separation. Multiple biochemical pathways regulate SG biology. The major signalling pathways regulating SG formation include the mammalian target of rapamycin (mTOR)-eukaryotic translation initiation factor 4F (eIF4F) and eIF2α pathways, whereas the pathways regulating SG dispersion and removal are mediated by valosin-containing protein and the autolysosomal cascade. Post-translational modifications of RBPs also strongly contribute to the regulation of SGs. Evidence indicates that SGs are supposed to be transient structures, but the chronic stresses associated with ageing lead to chronic, persistent SGs that appear to act as a nidus for the aggregation of disease-related proteins. We suggest a model describing how intrinsic vulnerabilities within the cellular RNA metabolism might lead to the pathological aggregation of RBPs when SGs become persistent. This process might accelerate the pathophysiology of many neurodegenerative diseases and myopathies, and it suggests new targets for disease intervention.
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Affiliation(s)
- Benjamin Wolozin
- Department of Pharmacology, Boston University School of Medicine, Boston, MA, USA.
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA.
| | - Pavel Ivanov
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
- The Broad Institute of Harvard and MIT, Cambridge, MA, USA
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50
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Sidor C, Borreguero-Munoz N, Fletcher GC, Elbediwy A, Guillermin O, Thompson BJ. Mask family proteins ANKHD1 and ANKRD17 regulate YAP nuclear import and stability. eLife 2019; 8:e48601. [PMID: 31661072 PMCID: PMC6861002 DOI: 10.7554/elife.48601] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 10/29/2019] [Indexed: 12/13/2022] Open
Abstract
Mask family proteins were discovered in Drosophila to promote the activity of the transcriptional coactivator Yorkie (Yki), the sole fly homolog of mammalian YAP (YAP1) and TAZ (WWTR1). The molecular function of Mask, or its mammalian homologs Mask1 (ANKHD1) and Mask2 (ANKRD17), remains unclear. Mask family proteins contain two ankyrin repeat domains that bind Yki/YAP as well as a conserved nuclear localisation sequence (NLS) and nuclear export sequence (NES), suggesting a role in nucleo-cytoplasmic transport. Here we show that Mask acts to promote nuclear import of Yki, and that addition of an ectopic NLS to Yki is sufficient to bypass the requirement for Mask in Yki-driven tissue growth. Mammalian Mask1/2 proteins also promote nuclear import of YAP, as well as stabilising YAP and driving formation of liquid droplets. Mask1/2 and YAP normally colocalise in a granular fashion in both nucleus and cytoplasm, and are co-regulated during mechanotransduction.
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Affiliation(s)
- Clara Sidor
- Epithelial Biology LaboratoryFrancis Crick InstituteLondonUnited Kingdom
| | | | | | - Ahmed Elbediwy
- Epithelial Biology LaboratoryFrancis Crick InstituteLondonUnited Kingdom
| | - Oriane Guillermin
- Epithelial Biology LaboratoryFrancis Crick InstituteLondonUnited Kingdom
| | - Barry J Thompson
- Epithelial Biology LaboratoryFrancis Crick InstituteLondonUnited Kingdom
- EMBL Australia, ACRF Department of Cancer Biology and TherapeuticsJohn Curtin School of Medical Research, The Australian National UniversityCanberraAustralia
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