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Mahendran TS, Wadsworth GM, Singh A, Banerjee PR. Biomolecular Condensates Can Enhance Pathological RNA Clustering. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.11.598371. [PMID: 38915678 PMCID: PMC11195159 DOI: 10.1101/2024.06.11.598371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Intracellular aggregation of repeat expanded RNA has been implicated in many neurological disorders. Here, we study the role of biomolecular condensates on irreversible RNA clustering. We find that physiologically relevant and disease-associated repeat RNAs spontaneously undergo an age-dependent percolation transition inside multi-component protein-nucleic acid condensates to form nanoscale clusters. Homotypic RNA clusters drive the emergence of multiphasic condensate structures with an RNA-rich solid core surrounded by an RNA-depleted fluid shell. The timescale of the RNA clustering, which drives a liquid-to-solid transition of biomolecular condensates, is determined by the sequence features, stability of RNA secondary structure, and repeat length. Importantly, G3BP1, the core scaffold of stress granules, introduces heterotypic buffering to homotypic RNA-RNA interactions and impedes intra-condensate RNA clustering in an ATP-independent manner. Our work suggests that biomolecular condensates can act as sites for RNA aggregation. It also highlights the functional role of RNA-binding proteins in suppressing aberrant RNA phase transitions.
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Affiliation(s)
| | | | - Anurag Singh
- Department of Physics, University at Buffalo, Buffalo, NY, 14260, USA
| | - Priya R. Banerjee
- Department of Biology, University at Buffalo, Buffalo, NY, 14260, USA
- Department of Physics, University at Buffalo, Buffalo, NY, 14260, USA
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Li L, Bi X, Wu X, Chen Z, Cao Y, Zhao G. Improving vitrification efficiency of human in vitro matured oocytes by the addition of LEA proteins. Hum Reprod 2024; 39:1275-1290. [PMID: 38592717 DOI: 10.1093/humrep/deae065] [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: 10/10/2023] [Revised: 03/01/2024] [Indexed: 04/10/2024] Open
Abstract
STUDY QUESTION Can the addition of late embryogenesis-abundant (LEA) proteins as a cryoprotective agent during the vitrification cryopreservation of in vitro matured oocytes enhance their developmental potential after fertilization? SUMMARY ANSWER LEA proteins improve the developmental potential of human in vitro matured oocytes following cryopreservation, mostly by downregulating FOS genes, reducing oxidative stress, and inhibiting the formation of ice crystals. WHAT IS KNOWN ALREADY Various factors in the vitrification process, including cryoprotectant toxicity, osmotic stress, and ice crystal formation during rewarming, can cause fatal damage to oocytes, thereby affecting the oocytes developmental potential and subsequent clinical outcomes. Recent studies have shown that LEA proteins possess high hydrophilicity and inherent stress tolerance, and can reduce low-temperature damage, although the molecular mechanism it exerts protective effects is still unclear. STUDY DESIGN, SIZE, DURATION Two LEA proteins extracted and purified by us were added to solutions for vitrification-warming of oocytes at concentrations of 10, 100, and 200 µg/mL, to determine the optimal protective concentration for each protein. Individual oocyte samples were collected for transcriptomic analysis, with each group consisting of three sample replicates. PARTICIPANTS/MATERIALS, SETTING, METHODS Immature oocytes were collected from patients who were undergoing combined in vitro fertilization (IVF) treatment and who had met the designated inclusion and exclusion criteria. These oocytes underwent in vitro maturation (IVM) culture for experimental research. A fluorescence microscope was used to detect the levels of mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and calcium in the mitochondria of vitrified-warmed human oocytes treated with different concentrations of LEA proteins, and the protective effect of the protein on mitochondrial function was assessed. The levels of intracellular ice recrystallization inhibition (IRI) in human oocytes after vitrification-warming were characterized by the cryomicroscope, to determine the LEA proteins inhibitory effect on recrystallization. By analyzing transcriptome sequencing data to investigate the potential mechanism through which LEA proteins exert their cryoprotective effects. MAIN RESULTS AND THE ROLE OF CHANCE The secondary structures of AfrLEA2 and AfrLEA3m proteins were shown to consist of a large number of α-helices and the proteins were shown to be highly hydrophilic, in agreement with previous reports. Confocal microscopy results showed that the immunofluorescence of AfrLEA2-FITC and AfrLEA3m-FITC-labeled proteins appeared to be extracellular and did not penetrate the cell membrane compared with the fluorescein isothiocyanate (FITC) control group, indicating that both AfrLEA2 and AfrLEA3m proteins were extracellular. The group treated with 100 µg/mL AfrLEA2 or AfrLEA3m protein had more uniform cytoplasmic particles and fewer vacuoles compared to the 10 and 200 µg/mL groups and were closest to the fresh group. In the 100 µg/mL groups, MMPs were significantly higher while ROS and calcium levels were significantly lower than those in the control group and were closer to the levels observed in fresh oocytes. Meanwhile, 100 µg/mL of AfrLEA2 or AfrLEA3m protein caused smaller ice crystal formation in the IRI assay compared to the control group treated with dimethylsulphoxide (DMSO) and ethylene glycol (EG); thus, the recrystallization inhibition was superior to that with the conventional cryoprotectants DMSO and EG. Further results revealed that the proteins improved the developmental potential of human oocytes following cryopreservation, likely by downregulating FOS genes and reducing oxidative stress. LIMITATIONS, REASONS FOR CAUTION The in vitro-matured metaphase II (IVM-MII) oocytes used in the study, due to ethical constraints, may not accurately reflect the condition of MII oocytes in general. The AfrLEA2 and AfrLEA3m proteins are recombinant proteins and their synthetic stability needs to be further explored. WIDER IMPLICATIONS OF THE FINDINGS LEA proteins, as a non-toxic and effective cryoprotectant, can reduce the cryoinjury of oocytes during cryopreservation. It provides a new promising method for cryopreservation of various cell types. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by the National Key Research and Development Program of China (2022YFC2703000) and the National Natural Science Foundation of China (52206064). The authors declare no competing interest. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
- Lu Li
- Department of Histology and Embryology, School of Basic Medicine Sciences, Anhui Medical University, Hefei, P.R. China
- Center of Reproductive Medicine, Children's Hospital of Shanxi and Women Health Center of Shanxi, Taiyuan, P.R. China
| | - Xingyu Bi
- Center of Reproductive Medicine, Children's Hospital of Shanxi and Women Health Center of Shanxi, Taiyuan, P.R. China
| | - Xueqing Wu
- Center of Reproductive Medicine, Children's Hospital of Shanxi and Women Health Center of Shanxi, Taiyuan, P.R. China
| | - Zhongrong Chen
- Department of Medical Engineering and Instrumentation, School of Biomedical Engineering, Anhui Medical University, Hefei, P. R. China
| | - Yunxia Cao
- Department of Obstetrics and Gynecology, Reproductive Medicine Center, The First Affiliated Hospital of Anhui Medical University, Hefei, P. R. China
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, Hefei, P. R. China
| | - Gang Zhao
- Department of Histology and Embryology, School of Basic Medicine Sciences, Anhui Medical University, Hefei, P.R. China
- Department of Medical Engineering and Instrumentation, School of Biomedical Engineering, Anhui Medical University, Hefei, P. R. China
- Department of Electronic Engineering and Information Science, University of Science and Technology of China, Hefei, P. R. China
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Koyama T, Iso N, Norizoe Y, Sakaue T, Yoshimura SH. Charge block-driven liquid-liquid phase separation - mechanism and biological roles. J Cell Sci 2024; 137:jcs261394. [PMID: 38855848 DOI: 10.1242/jcs.261394] [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: 06/11/2024] Open
Abstract
Liquid-liquid phase separation (LLPS) has increasingly been found to play pivotal roles in a number of intracellular events and reactions, and has introduced a new paradigm in cell biology to explain protein-protein and enzyme-ligand interactions beyond conventional molecular and biochemical theories. LLPS is driven by the cumulative effects of weak and promiscuous interactions, including electrostatic, hydrophobic and cation-π interactions, among polypeptides containing intrinsically disordered regions (IDRs) and describes the macroscopic behaviours of IDR-containing proteins in an intracellular milieu. Recent studies have revealed that interactions between 'charge blocks' - clusters of like charges along the polypeptide chain - strongly induce LLPS and play fundamental roles in its spatiotemporal regulation. Introducing a new parameter, termed 'charge blockiness', into physicochemical models of disordered polypeptides has yielded a better understanding of how the intrinsic amino acid sequence of a polypeptide determines the spatiotemporal occurrence of LLPS within a cell. Charge blockiness might also explain why some post-translational modifications segregate within IDRs and how they regulate LLPS. In this Review, we summarise recent progress towards understanding the mechanism and biological roles of charge block-driven LLPS and discuss how this new characteristic parameter of polypeptides offers new possibilities in the fields of structural biology and cell biology.
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Affiliation(s)
- Tetsu Koyama
- Department of Physical Sciences, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan
| | - Naoki Iso
- Department of Physical Sciences, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan
| | - Yuki Norizoe
- Department of Physical Sciences, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan
| | - Takahiro Sakaue
- Department of Physical Sciences, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan
| | - Shige H Yoshimura
- Graduate School of Biostudies , Kyoto University, Yoshida-konoe, Sakyo-ku, Kyoto, 606-8501, Japan
- Center for Living Systems Information Science (CeLiSIS) , Kyoto University, Yoshida-Konoe-Cho, Sakyo-ku, Kyoto, 606-8501, Japan
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Chakraborty S, Mishra J, Roy A, Niharika, Manna S, Baral T, Nandi P, Patra S, Patra SK. Liquid-liquid phase separation in subcellular assemblages and signaling pathways: Chromatin modifications induced gene regulation for cellular physiology and functions including carcinogenesis. Biochimie 2024; 223:74-97. [PMID: 38723938 DOI: 10.1016/j.biochi.2024.05.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 03/08/2024] [Accepted: 05/04/2024] [Indexed: 05/24/2024]
Abstract
Liquid-liquid phase separation (LLPS) describes many biochemical processes, including hydrogel formation, in the integrity of macromolecular assemblages and existence of membraneless organelles, including ribosome, nucleolus, nuclear speckles, paraspeckles, promyelocytic leukemia (PML) bodies, Cajal bodies (all exert crucial roles in cellular physiology), and evidence are emerging day by day. Also, phase separation is well documented in generation of plasma membrane subdomains and interplay between membranous and membraneless organelles. Intrinsically disordered regions (IDRs) of biopolymers/proteins are the most critical sticking regions that aggravate the formation of such condensates. Remarkably, phase separated condensates are also involved in epigenetic regulation of gene expression, chromatin remodeling, and heterochromatinization. Epigenetic marks on DNA and histones cooperate with RNA-binding proteins through their IDRs to trigger LLPS for facilitating transcription. How phase separation coalesces mutant oncoproteins, orchestrate tumor suppressor genes expression, and facilitated cancer-associated signaling pathways are unravelling. That autophagosome formation and DYRK3-mediated cancer stem cell modification also depend on phase separation is deciphered in part. In view of this, and to linchpin insight into the subcellular membraneless organelle assembly, gene activation and biological reactions catalyzed by enzymes, and the downstream physiological functions, and how all these events are precisely facilitated by LLPS inducing organelle function, epigenetic modulation of gene expression in this scenario, and how it goes awry in cancer progression are summarized and presented in this article.
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Affiliation(s)
- Subhajit Chakraborty
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, India
| | - Jagdish Mishra
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, India
| | - Ankan Roy
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, India
| | - Niharika
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, India
| | - Soumen Manna
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, India
| | - Tirthankar Baral
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, India
| | - Piyasa Nandi
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, India
| | - Subhajit Patra
- Department of Chemical Engineering, Maulana Azad National Institute of Technology, Bhopal, India
| | - Samir Kumar Patra
- Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, India.
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Nicchitta CV. An emerging role for the endoplasmic reticulum in stress granule biogenesis. Semin Cell Dev Biol 2024; 156:160-166. [PMID: 36202692 PMCID: PMC10208384 DOI: 10.1016/j.semcdb.2022.09.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 09/07/2022] [Accepted: 09/26/2022] [Indexed: 11/07/2022]
Abstract
Stress granules (SGs), structurally dynamic, optically resolvable, macromolecular assemblies of mRNAs, RNA binding proteins (RBPs), translation factors, ribosomal subunits, as well as other interacting proteins, assemble in response to cell stress conditions that elicit phosphorylation of eukaryotic initiation factor 2α (eIF2α) and consequently, the inactivation of translation initiation. SG biology is conserved throughout eukaryotes and has recently been linked to the pathological sequelae of neurodegenerative disorders, cancer biology, and viral infection. Substantial insights into mechanisms of SG biogenesis, and more broadly the phenomenon of biological liquid-liquid phase separation (LLPS), have been aided by detailed proteomic and transcriptomic studies as well as in vitro reconstitution approaches. A particularly interesting and largely unexplored element of SG biology is the cell biological context of SG biogenesis, including its subcellular organization and more recently, evidence that the endoplasmic reticulum (ER) membrane may serve important functions in RNA granule biology generally and SG biogenesis specifically. A central role for the ER in SG biogenesis is discussed and a hypothesis linking SG formation on the ER to the trafficking, localization and de novo translation of newly exported mRNAs is presented.
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Maier J, Sieme D, Wong LE, Dar F, Wienands J, Becker S, Griesinger C. Quantitative description of the phase-separation behavior of the multivalent SLP65-CIN85 complex. PNAS NEXUS 2024; 3:pgae079. [PMID: 38463037 PMCID: PMC10923291 DOI: 10.1093/pnasnexus/pgae079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 02/06/2024] [Indexed: 03/12/2024]
Abstract
Biomolecular condensates play a major role in cell compartmentalization, besides membrane-enclosed organelles. The multivalent SLP65 and CIN85 proteins are proximal B-cell antigen receptor (BCR) signal effectors and critical for proper immune responses. In association with intracellular vesicles, the two effector proteins form phase separated condensates prior to antigen stimulation, thereby preparing B lymphocytes for rapid and effective activation upon BCR ligation. Within this tripartite system, 6 proline-rich motifs (PRMs) of SLP65 interact promiscuously with 3 SH3 domains of the CIN85 monomer, establishing 18 individual SH3-PRM interactions whose individual dissociation constants we determined. Based on these 18 dissociation constants, we measured the phase-separation properties of the natural SLP65/CIN85 system as well as designer constructs that emphasize the strongest SH3/PRM interactions. By modeling these various SLP65/CIN85 constructs with the program LASSI (LAttice simulation engine for Sticker and Spacer Interactions), we reproduced the observed phase-separation properties. In addition, LASSI revealed a deviation in the experimental measurement, which was independently identified as a previously unknown intramolecular interaction. Thus, thermodynamic properties of the individual PRM/SH3 interactions allow us to model the phase-separation behavior of the SLP65/CIN85 system faithfully.
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Affiliation(s)
- Joachim Maier
- Department of NMR Based Structural Biology, Max Planck Institute (MPI) for Multidisciplinary Sciences, 37077 Göttingen, Germany
| | - Daniel Sieme
- Department of NMR Based Structural Biology, Max Planck Institute (MPI) for Multidisciplinary Sciences, 37077 Göttingen, Germany
| | - Leo E Wong
- Department of NMR Based Structural Biology, Max Planck Institute (MPI) for Multidisciplinary Sciences, 37077 Göttingen, Germany
| | - Furqan Dar
- Department of Biomedical Engineering, Washington University in St Louis, St Louis, MO 63130, USA
| | - Jürgen Wienands
- Institute of Cellular and Molecular Immunology, University Medical Center Göttingen, 37073 Göttingen, Germany
| | - Stefan Becker
- Department of NMR Based Structural Biology, Max Planck Institute (MPI) for Multidisciplinary Sciences, 37077 Göttingen, Germany
| | - Christian Griesinger
- Department of NMR Based Structural Biology, Max Planck Institute (MPI) for Multidisciplinary Sciences, 37077 Göttingen, Germany
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Wang F, Zhang Y. Physiology and pharmacological targeting of phase separation. J Biomed Sci 2024; 31:11. [PMID: 38245749 PMCID: PMC10800077 DOI: 10.1186/s12929-024-00993-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 01/04/2024] [Indexed: 01/22/2024] Open
Abstract
Liquid-liquid phase separation (LLPS) in biology describes a process by which proteins form membraneless condensates within a cellular compartment when conditions are met, including the concentration and posttranslational modifications of the protein components, the condition of the aqueous solution (pH, ionic strength, pressure, and temperature), and the existence of assisting factors (such as RNAs or other proteins). In these supramolecular liquid droplet-like inclusion bodies, molecules are held together through weak intermolecular and/or intramolecular interactions. With the aid of LLPS, cells can assemble functional sub-units within a given cellular compartment by enriching or excluding specific factors, modulating cellular function, and rapidly responding to environmental or physiological cues. Hence, LLPS is emerging as an important means to regulate biology and physiology. Yet, excessive inclusion body formation by, for instance, higher-than-normal concentrations or mutant forms of the protein components could result in the conversion from dynamic liquid condensates into more rigid gel- or solid-like aggregates, leading to the disruption of the organelle's function followed by the development of human disorders like neurodegenerative diseases. In summary, well-controlled formation and de-formation of LLPS is critical for normal biology and physiology from single cells to individual organisms, whereas abnormal LLPS is involved in the pathophysiology of human diseases. In turn, targeting these aggregates or their formation represents a promising approach in treating diseases driven by abnormal LLPS including those neurodegenerative diseases that lack effective therapies.
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Affiliation(s)
- Fangfang Wang
- Department of Pharmacology, School of Medicine, Case Comprehensive Cancer Center, Case Western Reserve University, 2109 Adelbert Road, W309A, Cleveland, OH, 44106, USA
| | - Youwei Zhang
- Department of Pharmacology, School of Medicine, Case Comprehensive Cancer Center, Case Western Reserve University, 2109 Adelbert Road, W309A, Cleveland, OH, 44106, USA.
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Gorsheneva NA, Sopova JV, Azarov VV, Grizel AV, Rubel AA. Biomolecular Condensates: Structure, Functions, Methods of Research. BIOCHEMISTRY. BIOKHIMIIA 2024; 89:S205-S223. [PMID: 38621751 DOI: 10.1134/s0006297924140116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/12/2023] [Accepted: 10/16/2023] [Indexed: 04/17/2024]
Abstract
The term "biomolecular condensates" is used to describe membraneless compartments in eukaryotic cells, accumulating proteins and nucleic acids. Biomolecular condensates are formed as a result of liquid-liquid phase separation (LLPS). Often, they demonstrate properties of liquid-like droplets or gel-like aggregates; however, some of them may appear to have a more complex structure and high-order organization. Membraneless microcompartments are involved in diverse processes both in cytoplasm and in nucleus, among them ribosome biogenesis, regulation of gene expression, cell signaling, and stress response. Condensates properties and structure could be highly dynamic and are affected by various internal and external factors, e.g., concentration and interactions of components, solution temperature, pH, osmolarity, etc. In this review, we discuss variety of biomolecular condensates and their functions in live cells, describe their structure variants, highlight domain and primary sequence organization of the constituent proteins and nucleic acids. Finally, we describe current advances in methods that characterize structure, properties, morphology, and dynamics of biomolecular condensates in vitro and in vivo.
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Affiliation(s)
| | - Julia V Sopova
- St. Petersburg State University, St. Petersburg, 199034, Russia.
| | | | - Anastasia V Grizel
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA.
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Fuentes-Jiménez DA, Salinas LS, Morales-Oliva E, Ramírez-Ramírez VA, Arciniega M, Navarro RE. Two predicted α-helices within the prion-like domain of TIAR-1 play a crucial role in its association with stress granules in Caenorhabditis elegans. Front Cell Dev Biol 2023; 11:1265104. [PMID: 38161334 PMCID: PMC10757852 DOI: 10.3389/fcell.2023.1265104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 11/14/2023] [Indexed: 01/03/2024] Open
Abstract
Stress granules (SGs) are sites for mRNA storage, protection, and translation repression. TIA1 and TIAR1 are two RNA-binding proteins that are key players in SGs formation in mammals. TIA1/TIAR have a prion-like domain (PrD) in their C-terminal that promotes liquid-phase separation. Lack of any TIA1/TIAR has severe consequences in mice. However, it is not clear whether the failure to form proper SGs is the cause of any of these problems. We disrupted two predicted α-helices within the prion-like domain of the Caenohabditis elegans TIA1/TIAR homolog, TIAR-1, to test whether its association with SGs is important for the nematode. We found that tiar-1 PrD mutant animals continued to form TIAR-1 condensates under stress in the C. elegans gonad. Nonetheless, TIAR-1 condensates appeared fragile and disassembled quickly after stress. Apparently, the SGs continued to associate regularly as observed with CGH-1, an SG marker. Like tiar-1-knockout nematodes, tiar-1 PrD mutant animals exhibited fertility problems and a shorter lifespan. Notwithstanding this, tiar-1 PrD mutant nematodes were no sensitive to stress. Our data demonstrate that the predicted prion-like domain of TIAR-1 is important for its association with stress granules. Moreover, this domain may also play a significant role in various TIAR-1 functions unrelated to stress, such as fertility, embryogenesis and lifespan.
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Affiliation(s)
- D. A. Fuentes-Jiménez
- Departamento de Biología Celular y Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - L. S. Salinas
- Departamento de Biología Celular y Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - E. Morales-Oliva
- Departamento de Biología Celular y Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - V. A. Ramírez-Ramírez
- Departamento de Biología Celular y Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - M. Arciniega
- Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - R. E. Navarro
- Departamento de Biología Celular y Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
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Gao G, Sumrall ES, Pitchiaya S, Bitzer M, Alberti S, Walter NG. Biomolecular condensates in kidney physiology and disease. Nat Rev Nephrol 2023; 19:756-770. [PMID: 37752323 DOI: 10.1038/s41581-023-00767-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/27/2023] [Indexed: 09/28/2023]
Abstract
The regulation and preservation of distinct intracellular and extracellular solute microenvironments is crucial for the maintenance of cellular homeostasis. In mammals, the kidneys control bodily salt and water homeostasis. Specifically, the urine-concentrating mechanism within the renal medulla causes fluctuations in extracellular osmolarity, which enables cells of the kidney to either conserve or eliminate water and electrolytes, depending on the balance between intake and loss. However, relatively little is known about the subcellular and molecular changes caused by such osmotic stresses. Advances have shown that many cells, including those of the kidney, rapidly (within seconds) and reversibly (within minutes) assemble membraneless, nano-to-microscale subcellular assemblies termed biomolecular condensates via the biophysical process of hyperosmotic phase separation (HOPS). Mechanistically, osmotic cell compression mediates changes in intracellular hydration, concentration and molecular crowding, rendering HOPS one of many related phase-separation phenomena. Osmotic stress causes numerous homo-multimeric proteins to condense, thereby affecting gene expression and cell survival. HOPS rapidly regulates specific cellular biochemical processes before appropriate protective or corrective action by broader stress response mechanisms can be initiated. Here, we broadly survey emerging evidence for, and the impact of, biomolecular condensates in nephrology, where initial concentration buffering by HOPS and its subsequent cellular escalation mechanisms are expected to have important implications for kidney physiology and disease.
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Affiliation(s)
- Guoming Gao
- Biophysics Graduate Program, University of Michigan, Ann Arbor, MI, USA
- Department of Chemistry and Center for RNA Biomedicine, University of Michigan, Ann Arbor, MI, USA
| | - Emily S Sumrall
- Biophysics Graduate Program, University of Michigan, Ann Arbor, MI, USA
- Department of Chemistry and Center for RNA Biomedicine, University of Michigan, Ann Arbor, MI, USA
| | | | - Markus Bitzer
- Department of Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Simon Alberti
- Technische Universität Dresden, Biotechnology Center (BIOTEC) and Center for Molecular and Cellular Engineering (CMCB), Dresden, Germany
| | - Nils G Walter
- Department of Chemistry and Center for RNA Biomedicine, University of Michigan, Ann Arbor, MI, USA.
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11
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LaPeruta AJ, Micic J, Woolford Jr. JL. Additional principles that govern the release of pre-ribosomes from the nucleolus into the nucleoplasm in yeast. Nucleic Acids Res 2023; 51:10867-10883. [PMID: 35736211 PMCID: PMC10639060 DOI: 10.1093/nar/gkac430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 05/05/2022] [Accepted: 06/20/2022] [Indexed: 11/14/2022] Open
Abstract
During eukaryotic ribosome biogenesis, pre-ribosomes travel from the nucleolus, where assembly is initiated, to the nucleoplasm and then are exported to the cytoplasm, where assembly concludes. Although nuclear export of pre-ribosomes has been extensively investigated, the release of pre-ribosomes from the nucleolus is an understudied phenomenon. Initial data indicate that unfolded rRNA interacts in trans with nucleolar components and that, when rRNA folds due to ribosomal protein (RP) binding, the number of trans interactions drops below the threshold necessary for nucleolar retention. To validate and expand on this idea, we performed a bioinformatic analysis of the protein components of the Saccharomyces cerevisiae ribosome assembly pathway. We found that ribosome biogenesis factors (RiBi factors) contain significantly more predicted trans interacting regions than RPs. We also analyzed cryo-EM structures of ribosome assembly intermediates to determine how nucleolar pre-ribosomes differ from post-nucleolar pre-ribosomes, specifically the capacity of RPs, RiBi factors, and rRNA components to interact in trans. We observed a significant decrease in the theoretical trans-interacting capability of pre-ribosomes between nucleolar and post-nucleolar stages of assembly due to the release of RiBi factors from particles and the folding of rRNA. Here, we provide a mechanism for the release of pre-ribosomes from the nucleolus.
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Affiliation(s)
- Amber J LaPeruta
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Jelena Micic
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - John L Woolford Jr.
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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12
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O’Connell LC, Johnson V, Hutton AK, Otis JP, Murthy AC, Liang MC, Wang SH, Fawzi NL, Mowry KL. Intrinsically disordered regions and RNA binding domains contribute to protein enrichment in biomolecular condensates in Xenopus oocytes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.10.566489. [PMID: 37986933 PMCID: PMC10659413 DOI: 10.1101/2023.11.10.566489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Proteins containing both intrinsically disordered regions (IDRs) and RNA binding domains (RBDs) can phase separate in vitro, forming bodies similar to cellular biomolecular condensates. However, how IDR and RBD domains contribute to in vivo recruitment of proteins to biomolecular condensates remains poorly understood. Here, we analyzed the roles of IDRs and RBDs in L-bodies, biomolecular condensates present in Xenopus oocytes. We show that a cytoplasmic isoform of hnRNPAB, which contains two RBDs and an IDR, is highly enriched in L-bodies. While both of these domains contribute to hnRNPAB self-association and phase separation in vitro and mediate enrichment into L-bodies in oocytes, neither the RBDs nor the IDR replicate the localization of full-length hnRNPAB. Our results suggest a model where the additive effects of the IDR and RBDs regulate hnRNPAB partitioning into L-bodies. This model likely has widespread applications as proteins containing RBD and IDR domains are common biomolecular condensate residents.
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Affiliation(s)
- Liam C. O’Connell
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University Providence, RI 02912, USA
| | - Victoria Johnson
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University Providence, RI 02912, USA
| | - Anika K. Hutton
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University Providence, RI 02912, USA
| | - Jessica P. Otis
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University Providence, RI 02912, USA
| | - Anastasia C. Murthy
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University Providence, RI 02912, USA
| | - Mark C. Liang
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University Providence, RI 02912, USA
| | - Szu-Huan Wang
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University Providence, RI 02912, USA
| | - Nicolas L. Fawzi
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University Providence, RI 02912, USA
| | - Kimberly L. Mowry
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University Providence, RI 02912, USA
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13
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LaPeruta AJ, Hedayati S, Micic J, Fitzgerald F, Kim D, Oualline G, Woolford JL. Yeast ribosome biogenesis factors Puf6 and Nog2 and ribosomal proteins uL2 and eL43 act in concert to facilitate the release of nascent large ribosomal subunits from the nucleolus. Nucleic Acids Res 2023; 51:11277-11290. [PMID: 37811893 PMCID: PMC10639061 DOI: 10.1093/nar/gkad794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 09/11/2023] [Accepted: 09/22/2023] [Indexed: 10/10/2023] Open
Abstract
Large ribosomal subunit precursors (pre-LSUs) are primarily synthesized in the nucleolus. At an undetermined step in their assembly, they are released into the nucleoplasm. Structural models of yeast pre-LSUs at various stages of assembly have been collected using cryo-EM. However, which cryo-EM model is closest to the final nucleolar intermediate of the LSU has yet to be determined. To elucidate the mechanisms of the release of pre-LSUs from the nucleolus, we assayed effects of depleting or knocking out two yeast ribosome biogenesis factors (RiBi factors), Puf6 and Nog2, and two ribosomal proteins, uL2 and eL43. These proteins function during or stabilize onto pre-LSUs between the late nucleolar stages to early nucleoplasmic stages of ribosome biogenesis. By characterizing the phenotype of these four mutants, we determined that a particle that is intermediate between the cryo-EM model State NE1 and State NE2 likely represents the final nucleolar assembly intermediate of the LSU. We conclude that the release of the RiBi factors Nip7, Nop2 and Spb1 and the subsequent stabilization of rRNA domains IV and V may be key triggers for the release of pre-LSUs from the nucleolus.
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Affiliation(s)
- Amber J LaPeruta
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Stefanie Hedayati
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Jelena Micic
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Fiona Fitzgerald
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - David Kim
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Grace Oualline
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - John L Woolford
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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14
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Ripin N, Parker R. Formation, function, and pathology of RNP granules. Cell 2023; 186:4737-4756. [PMID: 37890457 PMCID: PMC10617657 DOI: 10.1016/j.cell.2023.09.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 07/28/2023] [Accepted: 09/07/2023] [Indexed: 10/29/2023]
Abstract
Ribonucleoprotein (RNP) granules are diverse membrane-less organelles that form through multivalent RNA-RNA, RNA-protein, and protein-protein interactions between RNPs. RNP granules are implicated in many aspects of RNA physiology, but in most cases their functions are poorly understood. RNP granules can be described through four key principles. First, RNP granules often arise because of the large size, high localized concentrations, and multivalent interactions of RNPs. Second, cells regulate RNP granule formation by multiple mechanisms including posttranslational modifications, protein chaperones, and RNA chaperones. Third, RNP granules impact cell physiology in multiple manners. Finally, dysregulation of RNP granules contributes to human diseases. Outstanding issues in the field remain, including determining the scale and molecular mechanisms of RNP granule function and how granule dysfunction contributes to human disease.
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Affiliation(s)
- Nina Ripin
- Department of Biochemistry and Howard Hughes Medical Institute, University of Colorado Boulder, Boulder, CO 80303, USA
| | - Roy Parker
- Department of Biochemistry and Howard Hughes Medical Institute, University of Colorado Boulder, Boulder, CO 80303, USA.
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15
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Qin C, Wang YL, Zhou JY, Shi J, Zhao WW, Zhu YX, Bai SM, Feng LL, Bie SY, Zeng B, Zheng J, Zeng GD, Feng WX, Wan XB, Fan XJ. RAP80 phase separation at DNA double-strand break promotes BRCA1 recruitment. Nucleic Acids Res 2023; 51:9733-9747. [PMID: 37638744 PMCID: PMC10570032 DOI: 10.1093/nar/gkad686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Revised: 07/29/2023] [Accepted: 08/17/2023] [Indexed: 08/29/2023] Open
Abstract
RAP80 has been characterized as a component of the BRCA1-A complex and is responsible for the recruitment of BRCA1 to DNA double-strand breaks (DSBs). However, we and others found that the recruitment of RAP80 and BRCA1 were not absolutely temporally synchronized, indicating that other mechanisms, apart from physical interaction, might be implicated. Recently, liquid-liquid phase separation (LLPS) has been characterized as a novel mechanism for the organization of key signaling molecules to drive their particular cellular functions. Here, we characterized that RAP80 LLPS at DSB was required for RAP80-mediated BRCA1 recruitment. Both cellular and in vitro experiments showed that RAP80 phase separated at DSB, which was ascribed to a highly disordered region (IDR) at its N-terminal. Meanwhile, the Lys63-linked poly-ubiquitin chains that quickly formed after DSBs occur, strongly enhanced RAP80 phase separation and were responsible for the induction of RAP80 condensation at the DSB site. Most importantly, abolishing the condensation of RAP80 significantly suppressed the formation of BRCA1 foci, encovering a pivotal role of RAP80 condensates in BRCA1 recruitment and radiosensitivity. Together, our study disclosed a new mechanism underlying RAP80-mediated BRCA1 recruitment, which provided new insight into the role of phase separation in DSB repair.
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Affiliation(s)
- Caolitao Qin
- Henan Provincial Key Laboratory of Radiation Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Yun-Long Wang
- Henan Provincial Key Laboratory of Radiation Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- Department of Radiation Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Jin-Ying Zhou
- Henan Provincial Key Laboratory of Radiation Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- Department of Radiation Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Jie Shi
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Wan-Wen Zhao
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Ya-Xi Zhu
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- Department of Pathology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Shao-Mei Bai
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- Department of Pathology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Li-Li Feng
- Department of Radiation Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, Guangdong 510655, P.R. China
| | - Shu-Ying Bie
- Henan Provincial Key Laboratory of Radiation Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- Department of Pathology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Bing Zeng
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- Department of Gastroenterology, Hernia and Abdominal Wall Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Jian Zheng
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Guang-Dong Zeng
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Wei-Xing Feng
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Xiang-Bo Wan
- Henan Provincial Key Laboratory of Radiation Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- Department of Radiation Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- Department of Radiation Oncology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
| | - Xin-Juan Fan
- Henan Provincial Key Laboratory of Radiation Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
- GuangDong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
- Department of Pathology, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510655, P.R. China
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16
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Wang T, Shi S, Shi Y, Jiang P, Hu G, Ye Q, Shi Z, Yu K, Wang C, Fan G, Zhao S, Ma H, Chang ACY, Li Z, Bian Q, Lin CP. Chemical-induced phase transition and global conformational reorganization of chromatin. Nat Commun 2023; 14:5556. [PMID: 37689690 PMCID: PMC10492836 DOI: 10.1038/s41467-023-41340-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 08/29/2023] [Indexed: 09/11/2023] Open
Abstract
Chemicals or drugs can accumulate within biomolecular condensates formed through phase separation in cells. Here, we use super-resolution imaging to search for chemicals that induce phase transition within chromatin at the microscale. This microscopic screening approach reveals that adriamycin (doxorubicin) - a widely used anticancer drug that is known to interact with chromatin - specifically induces visible local condensation and global conformational change of chromatin in cancer and primary cells. Hi-C and ATAC-seq experiments systematically and quantitatively demonstrate that adriamycin-induced chromatin condensation is accompanied by weakened chromatin interaction within topologically associated domains, compartment A/B switching, lower chromatin accessibility, and corresponding transcriptomic changes. Mechanistically, adriamycin complexes with histone H1 and induces phase transition of H1, forming fibrous aggregates in vitro. These results reveal a phase separation-driven mechanism for a chemotherapeutic drug.
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Affiliation(s)
- Tengfei Wang
- School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China
| | - Shuxiang Shi
- School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China
- Lingang Laboratory, 200031, Shanghai, China
| | - Yuanyuan Shi
- Shanghai Institute of Precision Medicine, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 200125, Shanghai, China
- Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - Peipei Jiang
- Shanghai Institute of Precision Medicine, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 200125, Shanghai, China
- Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - Ganlu Hu
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, 201210, Shanghai, China
| | - Qinying Ye
- School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China
| | - Zhan Shi
- School of Physical Science and Technology, ShanghaiTech University, 201210, Shanghai, China
| | - Kexin Yu
- School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China
- iHuman Institute, ShanghaiTech University, 201010, Shanghai, China
| | - Chenguang Wang
- Shanghai Institute of Precision Medicine, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 200125, Shanghai, China
- Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
- Department of Cardiology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Guoping Fan
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, 201210, Shanghai, China
| | - Suwen Zhao
- School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China
- iHuman Institute, ShanghaiTech University, 201010, Shanghai, China
| | - Hanhui Ma
- School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China
| | - Alex C Y Chang
- Shanghai Institute of Precision Medicine, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 200125, Shanghai, China
- Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
- Department of Cardiology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhi Li
- School of Physical Science and Technology, ShanghaiTech University, 201210, Shanghai, China
| | - Qian Bian
- Shanghai Institute of Precision Medicine, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 200125, Shanghai, China.
- Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China.
| | - Chao-Po Lin
- School of Life Science and Technology, ShanghaiTech University, 201210, Shanghai, China.
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17
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Naskar A, Nayak A, Salaikumaran MR, Vishal SS, Gopal PP. Phase separation and pathologic transitions of RNP condensates in neurons: implications for amyotrophic lateral sclerosis, frontotemporal dementia and other neurodegenerative disorders. Front Mol Neurosci 2023; 16:1242925. [PMID: 37720552 PMCID: PMC10502346 DOI: 10.3389/fnmol.2023.1242925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 08/21/2023] [Indexed: 09/19/2023] Open
Abstract
Liquid-liquid phase separation results in the formation of dynamic biomolecular condensates, also known as membrane-less organelles, that allow for the assembly of functional compartments and higher order structures within cells. Multivalent, reversible interactions between RNA-binding proteins (RBPs), including FUS, TDP-43, and hnRNPA1, and/or RNA (e.g., RBP-RBP, RBP-RNA, RNA-RNA), result in the formation of ribonucleoprotein (RNP) condensates, which are critical for RNA processing, mRNA transport, stability, stress granule assembly, and translation. Stress granules, neuronal transport granules, and processing bodies are examples of cytoplasmic RNP condensates, while the nucleolus and Cajal bodies are representative nuclear RNP condensates. In neurons, RNP condensates promote long-range mRNA transport and local translation in the dendrites and axon, and are essential for spatiotemporal regulation of gene expression, axonal integrity and synaptic function. Mutations of RBPs and/or pathologic mislocalization and aggregation of RBPs are hallmarks of several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer's disease. ALS/FTD-linked mutations of RBPs alter the strength and reversibility of multivalent interactions with other RBPs and RNAs, resulting in aberrant phase transitions. These aberrant RNP condensates have detrimental functional consequences on mRNA stability, localization, and translation, and ultimately lead to compromised axonal integrity and synaptic function in disease. Pathogenic protein aggregation is dependent on various factors, and aberrant dynamically arrested RNP condensates may serve as an initial nucleation step for pathologic aggregate formation. Recent studies have focused on identifying mechanisms by which neurons resolve phase transitioned condensates to prevent the formation of pathogenic inclusions/aggregates. The present review focuses on the phase separation of neurodegenerative disease-linked RBPs, physiological functions of RNP condensates, and the pathologic role of aberrant phase transitions in neurodegenerative disease, particularly ALS/FTD. We also examine cellular mechanisms that contribute to the resolution of aberrant condensates in neurons, and potential therapeutic approaches to resolve aberrantly phase transitioned condensates at a molecular level.
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Affiliation(s)
- Aditi Naskar
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | - Asima Nayak
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | | | - Sonali S. Vishal
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
| | - Pallavi P. Gopal
- Department of Pathology, Yale School of Medicine, New Haven, CT, United States
- Program in Cellular Neuroscience, Neurodegeneration, and Repair, Yale School of Medicine, New Haven, CT, United States
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18
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Wang W, Wang C, Wang Y, Ma J, Wang T, Tao Z, Liu P, Li S, Hu Y, Gu A, Wang H, Qiu C, Li P. The P-body component DECAPPING5 and the floral repressor SISTER OF FCA regulate FLOWERING LOCUS C transcription in Arabidopsis. THE PLANT CELL 2023; 35:3303-3324. [PMID: 37220754 PMCID: PMC10473201 DOI: 10.1093/plcell/koad151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 03/28/2023] [Accepted: 04/30/2023] [Indexed: 05/25/2023]
Abstract
Flowering is the transition from vegetative to reproductive growth and is critical for plant adaptation and reproduction. FLOWERING LOCUS C (FLC) plays a central role in flowering time control, and dissecting its regulation mechanism provides essential information for crop improvement. Here, we report that DECAPPING5 (DCP5), a component of processing bodies (P-bodies), regulates FLC transcription and flowering time in Arabidopsis (Arabidopsis thaliana). DCP5 and its interacting partner SISTER OF FCA (SSF) undergo liquid-liquid phase separation (LLPS) that is mediated by their prion-like domains (PrDs). Enhancing or attenuating the LLPS of both proteins using transgenic methods greatly affects their ability to regulate FLC and flowering time. DCP5 regulates FLC transcription by modulating RNA polymerase II enrichment at the FLC locus. DCP5 requires SSF for FLC regulation, and loss of SSF or its PrD disrupts DCP5 function. Our results reveal that DCP5 interacts with SSF, and the nuclear DCP5-SSF complex regulates FLC expression at the transcriptional level.
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Affiliation(s)
- Wanyi Wang
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Chuanhong Wang
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Yunhe Wang
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Jing Ma
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Tengyue Wang
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Zhen Tao
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Peipei Liu
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Shuai Li
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Yuanyuan Hu
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Aiju Gu
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Hui Wang
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Chunhong Qiu
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
| | - Peijin Li
- The National Engineering Lab of Crop Stress Resistance Breeding, School of Life Sciences, Anhui Agricultural University, Hefei 230036, China
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19
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Solis-Miranda J, Chodasiewicz M, Skirycz A, Fernie AR, Moschou PN, Bozhkov PV, Gutierrez-Beltran E. Stress-related biomolecular condensates in plants. THE PLANT CELL 2023; 35:3187-3204. [PMID: 37162152 PMCID: PMC10473214 DOI: 10.1093/plcell/koad127] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 04/07/2023] [Accepted: 04/27/2023] [Indexed: 05/11/2023]
Abstract
Biomolecular condensates are membraneless organelle-like structures that can concentrate molecules and often form through liquid-liquid phase separation. Biomolecular condensate assembly is tightly regulated by developmental and environmental cues. Although research on biomolecular condensates has intensified in the past 10 years, our current understanding of the molecular mechanisms and components underlying their formation remains in its infancy, especially in plants. However, recent studies have shown that the formation of biomolecular condensates may be central to plant acclimation to stress conditions. Here, we describe the mechanism, regulation, and properties of stress-related condensates in plants, focusing on stress granules and processing bodies, 2 of the most well-characterized biomolecular condensates. In this regard, we showcase the proteomes of stress granules and processing bodies in an attempt to suggest methods for elucidating the composition and function of biomolecular condensates. Finally, we discuss how biomolecular condensates modulate stress responses and how they might be used as targets for biotechnological efforts to improve stress tolerance.
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Affiliation(s)
- Jorge Solis-Miranda
- Institutode Bioquimica Vegetal y Fotosintesis, Consejo Superior de Investigaciones Cientificas (CSIC)-Universidad de Sevilla, 41092 Sevilla, Spain
| | - Monika Chodasiewicz
- Biological and Environmental Science and Engineering Division, Center for Desert Agriculture, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | | | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, 14476 Potsdam-Golm, Germany
| | - Panagiotis N Moschou
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
- Department of Biology, University of Crete, Heraklion 71409, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion 70013, Greece
| | - Peter V Bozhkov
- Department of Molecular Sciences, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, 75007 Uppsala, Sweden
| | - Emilio Gutierrez-Beltran
- Institutode Bioquimica Vegetal y Fotosintesis, Consejo Superior de Investigaciones Cientificas (CSIC)-Universidad de Sevilla, 41092 Sevilla, Spain
- Departamento de Bioquimica Vegetal y Biologia Molecular, Facultad de Biologia, Universidad de Sevilla, 41012 Sevilla, Spain
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20
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Mohanty P, Shenoy J, Rizuan A, Mercado-Ortiz JF, Fawzi NL, Mittal J. A synergy between site-specific and transient interactions drives the phase separation of a disordered, low-complexity domain. Proc Natl Acad Sci U S A 2023; 120:e2305625120. [PMID: 37579155 PMCID: PMC10450430 DOI: 10.1073/pnas.2305625120] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 07/17/2023] [Indexed: 08/16/2023] Open
Abstract
TAR DNA-binding protein 43 (TDP-43) is involved in key processes in RNA metabolism and is frequently implicated in many neurodegenerative diseases, including amyotrophic lateral sclerosis and frontotemporal dementia. The prion-like, disordered C-terminal domain (CTD) of TDP-43 is aggregation-prone, can undergo liquid-liquid phase separation (LLPS) in isolation, and is critical for phase separation (PS) of the full-length protein under physiological conditions. While a short conserved helical region (CR, spanning residues 319-341) promotes oligomerization and is essential for LLPS, aromatic residues in the flanking disordered regions (QN-rich, IDR1/2) are also found to play a critical role in PS and aggregation. Compared with other phase-separating proteins, TDP-43 CTD has a notably distinct sequence composition including many aliphatic residues such as methionine and leucine. Aliphatic residues were previously suggested to modulate the apparent viscosity of the resulting phases, but their direct contribution toward CTD phase separation has been relatively ignored. Using multiscale simulations coupled with in vitro saturation concentration (csat) measurements, we identified the importance of aromatic residues while also suggesting an essential role for aliphatic methionine residues in promoting single-chain compaction and LLPS. Surprisingly, NMR experiments showed that transient interactions involving phenylalanine and methionine residues in the disordered flanking regions can directly enhance site-specific, CR-mediated intermolecular association. Overall, our work highlights an underappreciated mode of biomolecular recognition, wherein both transient and site-specific hydrophobic interactions act synergistically to drive the oligomerization and phase separation of a disordered, low-complexity domain.
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Affiliation(s)
- Priyesh Mohanty
- Artie McFerrinDepartment of Chemical Engineering, Texas A&M University, College Station, TX77843
| | - Jayakrishna Shenoy
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University, Providence, RI02912
| | - Azamat Rizuan
- Artie McFerrinDepartment of Chemical Engineering, Texas A&M University, College Station, TX77843
| | - José F. Mercado-Ortiz
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University, Providence, RI02912
| | - Nicolas L. Fawzi
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University, Providence, RI02912
| | - Jeetain Mittal
- Artie McFerrinDepartment of Chemical Engineering, Texas A&M University, College Station, TX77843
- Department of Chemistry, Texas A&M University, College Station, TX77843
- Interdisciplinary Graduate Program in Genetics and Genomics, Texas A&M University, College Station, TX77843
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21
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Liu Y, Yao Z, Lian G, Yang P. Biomolecular phase separation in stress granule assembly and virus infection. Acta Biochim Biophys Sin (Shanghai) 2023; 55:1099-1118. [PMID: 37401177 PMCID: PMC10415189 DOI: 10.3724/abbs.2023117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 05/06/2023] [Indexed: 07/05/2023] Open
Abstract
Liquid-liquid phase separation (LLPS) has emerged as a crucial mechanism for cellular compartmentalization. One prominent example of this is the stress granule. Found in various types of cells, stress granule is a biomolecular condensate formed through phase separation. It comprises numerous RNA and RNA-binding proteins. Over the past decades, substantial knowledge has been gained about the composition and dynamics of stress granules. SGs can regulate various signaling pathways and have been associated with numerous human diseases, such as neurodegenerative diseases, cancer, and infectious diseases. The threat of viral infections continues to loom over society. Both DNA and RNA viruses depend on host cells for replication. Intriguingly, many stages of the viral life cycle are closely tied to RNA metabolism in human cells. The field of biomolecular condensates has rapidly advanced in recent times. In this context, we aim to summarize research on stress granules and their link to viral infections. Notably, stress granules triggered by viral infections behave differently from the canonical stress granules triggered by sodium arsenite (SA) and heat shock. Studying stress granules in the context of viral infections could offer a valuable platform to link viral replication processes and host anti-viral responses. A deeper understanding of these biological processes could pave the way for innovative interventions and treatments for viral infectious diseases. They could potentially bridge the gap between basic biological processes and interactions between viruses and their hosts.
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Affiliation(s)
- Yi Liu
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
| | - Zhiying Yao
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
| | - Guiwei Lian
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
| | - Peiguo Yang
- />Westlake Laboratory of Life Sciences and BiomedicineSchool of Life SciencesWestlake UniversityHangzhou310030China
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22
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Schulte T, Panas MD, Han X, Williams L, Kedersha N, Fleck JS, Tan TJC, Dopico XC, Olsson A, Morro AM, Hanke L, Nilvebrant J, Giang KA, Nygren PÅ, Anderson P, Achour A, McInerney GM. Caprin-1 binding to the critical stress granule protein G3BP1 is influenced by pH. Open Biol 2023; 13:220369. [PMID: 37161291 PMCID: PMC10170197 DOI: 10.1098/rsob.220369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 03/28/2023] [Indexed: 05/11/2023] Open
Abstract
G3BP is the central node within stress-induced protein-RNA interaction networks known as stress granules (SGs). The SG-associated proteins Caprin-1 and USP10 bind mutually exclusively to the NTF2 domain of G3BP1, promoting and inhibiting SG formation, respectively. Herein, we present the crystal structure of G3BP1-NTF2 in complex with a Caprin-1-derived short linear motif (SLiM). Caprin-1 interacts with His-31 and His-62 within a third NTF2-binding site outside those covered by USP10, as confirmed using biochemical and biophysical-binding assays. Nano-differential scanning fluorimetry revealed reduced thermal stability of G3BP1-NTF2 at acidic pH. This destabilization was counterbalanced significantly better by bound USP10 than Caprin-1. The G3BP1/USP10 complex immunoprecipated from human U2OS cells was more resistant to acidic buffer washes than G3BP1/Caprin-1. Acidification of cellular condensates by approximately 0.5 units relative to the cytosol was detected by ratiometric fluorescence analysis of pHluorin2 fused to G3BP1. Cells expressing a Caprin-1/FGDF chimera with higher G3BP1-binding affinity had reduced Caprin-1 levels and slightly reduced condensate sizes. This unexpected finding may suggest that binding of the USP10-derived SLiM to NTF2 reduces the propensity of G3BP1 to enter condensates.
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Affiliation(s)
- Tim Schulte
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Division of Infectious Diseases, Karolinska University Hospital, Stockholm, 171 77, Sweden
| | - Marc D. Panas
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Xiao Han
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Division of Infectious Diseases, Karolinska University Hospital, Stockholm, 171 77, Sweden
| | - Lucy Williams
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Nancy Kedersha
- Division of Rheumatology, Immunity, and Inflammation, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Harvard Medical School Initiative for RNA Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Jonas Simon Fleck
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Division of Infectious Diseases, Karolinska University Hospital, Stockholm, 171 77, Sweden
| | - Timothy J. C. Tan
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Xaquin Castro Dopico
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Anders Olsson
- Protein Expression and Characterization, AlbaNova University Center, Royal Institute of Technology, 114 21, Stockholm
| | - Ainhoa Moliner Morro
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Leo Hanke
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Johan Nilvebrant
- Division of Protein Engineering, Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, AlbaNova University Center, Royal Institute of Technology, 114 21, Stockholm
- Science for Life Laboratory, Tomtebodavägen 23A, 171 65, Sweden
| | - Kim Anh Giang
- Division of Protein Engineering, Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, AlbaNova University Center, Royal Institute of Technology, 114 21, Stockholm
- Science for Life Laboratory, Tomtebodavägen 23A, 171 65, Sweden
| | - Per-Åke Nygren
- Division of Protein Engineering, Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, AlbaNova University Center, Royal Institute of Technology, 114 21, Stockholm
- Science for Life Laboratory, Tomtebodavägen 23A, 171 65, Sweden
| | - Paul Anderson
- Division of Rheumatology, Immunity, and Inflammation, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Harvard Medical School Initiative for RNA Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Adnane Achour
- Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Division of Infectious Diseases, Karolinska University Hospital, Stockholm, 171 77, Sweden
| | - Gerald M. McInerney
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, 171 77, Sweden
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23
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Decle-Carrasco S, Rodríguez-Piña AL, Rodríguez-Zapata LC, Castano E. Current research on viral proteins that interact with fibrillarin. Mol Biol Rep 2023; 50:4631-4643. [PMID: 36928641 PMCID: PMC10018631 DOI: 10.1007/s11033-023-08343-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 02/15/2023] [Indexed: 03/18/2023]
Abstract
The nucleolus is a multifunctional nuclear domain primarily dedicated to ribosome biogenesis. Certain viruses developed strategies to manipulate host nucleolar proteins to facilitate their replication by modulating ribosomal RNA (rRNA) processing. This association interferes with nucleolar functions resulting in overactivation or arrest of ribosome biogenesis, induction or inhibition of apoptosis, and affecting stress response. The nucleolar protein fibrillarin (FBL) is an important target of some plant and animal viruses. FBL is an essential and highly conserved S-adenosyl methionine (SAM) dependent methyltransferase, capable of rRNA degradation by its intrinsically disordered region (IDR), the glycine/arginine-rich (GAR) domain. It forms a ribonucleoprotein complex that directs 2'-O-methylations in more than 100 sites of pre-rRNAs. It is involved in multiple cellular processes, including initiation of transcription, oncogenesis, and apoptosis, among others. The interaction with animal viruses, including human viruses, triggered its redistribution to the nucleoplasm and cytoplasm, interfering with its role in pre-rRNA processing. Viral-encoded proteins with IDRs as nucleocapsids, matrix, Tat protein, and even a viral snoRNA, can associate with FBL, forcing the nucleolar protein to undergo atypical functions. Here we review the molecular mechanisms employed by animal and human viruses to usurp FBL functions and the effect on cellular processes, particularly in ribosome biogenesis.
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Affiliation(s)
- Stefano Decle-Carrasco
- Unidad de Bioquímica y Biología Molecular de Plantas. Centro de Investigación Científica de Yucatán, A.C. Calle 43 No. 130, Colonia Chuburná de Hidalgo, Mérida, Yucatán, México
| | - Alma Laura Rodríguez-Piña
- Unidad de Bioquímica y Biología Molecular de Plantas. Centro de Investigación Científica de Yucatán, A.C. Calle 43 No. 130, Colonia Chuburná de Hidalgo, Mérida, Yucatán, México
| | - Luis Carlos Rodríguez-Zapata
- Unidad de Biotecnología. Centro de Investigación Científica de Yucatán, A.C. Calle 43 No. 130, Colonia Chuburná de Hidalgo, Mérida, Yucatán, México
| | - Enrique Castano
- Unidad de Bioquímica y Biología Molecular de Plantas. Centro de Investigación Científica de Yucatán, A.C. Calle 43 No. 130, Colonia Chuburná de Hidalgo, Mérida, Yucatán, México.
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24
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Che X, Wu J, Liu H, Su J, Chen X. Cellular liquid-liquid phase separation: Concept, functions, regulations, and detections. J Cell Physiol 2023; 238:847-865. [PMID: 36870067 DOI: 10.1002/jcp.30980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 10/05/2022] [Accepted: 02/08/2023] [Indexed: 03/06/2023]
Abstract
Liquid-liquid phase separation is a multicomponent system separated into phases with different compositions and structures. It has been identified and explored in organisms after being introduced from the thermodynamic field. Condensate, the product of phase separation, exists in different scales of cellular structures, such as nucleolus, stress granules, and other organelles in nuclei or cytoplasm. And also play critical roles in different cellular behaviors. Here, we review the concept, thermodynamical and biochemical principles of phase separation. We summarized the main functions including the adjustment of biochemical reaction rates, the regulation of macromolecule folding state, subcellular structural support, the mediation of subcellular location, and intimately linked to different kinds of diseases, such as cancer and neurodegeneration. Advanced detection methods to investigate phase separation are collected and analyzed. We conclude with the discussion of anxiety of phase separation, and thought about how progress can be made to develop precise detection methods and disclose the potential application of condensates.
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Affiliation(s)
- Xuanlin Che
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,Hunan Key Laboratory of Skin Cancer and Psoriasis, Xiangya Hospital, Changsha, Hunan, China.,Hunan Engineering Research Center of Skin Health and Disease, Xiangya Hospital, Changsha, Hunan, China.,Xiangya Clinical Research Center for Cancer Immunotherapy, Central South University, Changsha, Hunan, China
| | - Jiajun Wu
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, China
| | - Hua Liu
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, China
| | - Juan Su
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,Hunan Key Laboratory of Skin Cancer and Psoriasis, Xiangya Hospital, Changsha, Hunan, China.,Hunan Engineering Research Center of Skin Health and Disease, Xiangya Hospital, Changsha, Hunan, China.,Xiangya Clinical Research Center for Cancer Immunotherapy, Central South University, Changsha, Hunan, China
| | - Xiang Chen
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, Hunan, China.,Hunan Key Laboratory of Skin Cancer and Psoriasis, Xiangya Hospital, Changsha, Hunan, China.,Hunan Engineering Research Center of Skin Health and Disease, Xiangya Hospital, Changsha, Hunan, China.,Xiangya Clinical Research Center for Cancer Immunotherapy, Central South University, Changsha, Hunan, China
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25
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Ainani H, Bouchmaa N, Ben Mrid R, El Fatimy R. Liquid-liquid phase separation of protein tau: An emerging process in Alzheimer's disease pathogenesis. Neurobiol Dis 2023; 178:106011. [PMID: 36702317 DOI: 10.1016/j.nbd.2023.106011] [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: 10/02/2022] [Revised: 01/04/2023] [Accepted: 01/21/2023] [Indexed: 01/24/2023] Open
Abstract
Metabolic reactions within cells occur in various isolated compartments with or without borders, the latter being known as membrane-less organelles (MLOs). The MLOs show liquid-like properties and are formed by a process known as liquid-liquid phase separation (LLPS). MLOs contribute to different molecules interactions such as protein-protein, protein-RNA, and RNA-RNA driven by various factors, such as multivalency of intrinsic disorders. MLOs are involved in several cell signaling pathways such as transcription, immune response, and cellular organization. However, disruption of these processes has been found in different pathologies. Recently, it has been demonstrated that protein aggregates, a characteristic of some neurodegenerative diseases, undergo similar phase separation. Tau protein is known as a major neurofibrillary tangles component in Alzheimer's disease (AD). This protein can undergo phase separation to form a MLO known as tau droplet in vitro and in vivo, and this process can be facilitated by several factors, including crowding agents, RNA, and phosphorylation. Tau droplet has been shown to mature into insoluble aggregates suggesting that this process may precede and induce neurodegeneration in AD. Here we review major factors involved in liquid droplet formation within a cell. Additionally, we highlight recent findings concerning tau aggregation following phase separation in AD, along with the potential therapeutic strategies that could be explored in this process against the progression of this pathology.
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Affiliation(s)
- Hassan Ainani
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco
| | - Najat Bouchmaa
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco
| | - Reda Ben Mrid
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco
| | - Rachid El Fatimy
- Institute of Biological Sciences (ISSB), UM6P-Faculty of Medical Sciences (UM6P-FMS), Mohammed VI Polytechnic University, Ben-Guerir, Morocco.
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26
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Millar SR, Huang JQ, Schreiber KJ, Tsai YC, Won J, Zhang J, Moses AM, Youn JY. A New Phase of Networking: The Molecular Composition and Regulatory Dynamics of Mammalian Stress Granules. Chem Rev 2023. [PMID: 36662637 PMCID: PMC10375481 DOI: 10.1021/acs.chemrev.2c00608] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Stress granules (SGs) are cytosolic biomolecular condensates that form in response to cellular stress. Weak, multivalent interactions between their protein and RNA constituents drive their rapid, dynamic assembly through phase separation coupled to percolation. Though a consensus model of SG function has yet to be determined, their perceived implication in cytoprotective processes (e.g., antiviral responses and inhibition of apoptosis) and possible role in the pathogenesis of various neurodegenerative diseases (e.g., amyotrophic lateral sclerosis and frontotemporal dementia) have drawn great interest. Consequently, new studies using numerous cell biological, genetic, and proteomic methods have been performed to unravel the mechanisms underlying SG formation, organization, and function and, with them, a more clearly defined SG proteome. Here, we provide a consensus SG proteome through literature curation and an update of the user-friendly database RNAgranuleDB to version 2.0 (http://rnagranuledb.lunenfeld.ca/). With this updated SG proteome, we use next-generation phase separation prediction tools to assess the predisposition of SG proteins for phase separation and aggregation. Next, we analyze the primary sequence features of intrinsically disordered regions (IDRs) within SG-resident proteins. Finally, we review the protein- and RNA-level determinants, including post-translational modifications (PTMs), that regulate SG composition and assembly/disassembly dynamics.
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Affiliation(s)
- Sean R Millar
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Jie Qi Huang
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Karl J Schreiber
- Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
| | - Yi-Cheng Tsai
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Jiyun Won
- Department of Cell & Systems Biology, University of Toronto, Toronto, Ontario M5S 3B2, Canada
| | - Jianping Zhang
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario M5G 1X5, Canada
| | - Alan M Moses
- Department of Cell & Systems Biology, University of Toronto, Toronto, Ontario M5S 3B2, Canada.,Department of Computer Science, University of Toronto, Toronto, Ontario M5T 3A1, Canada.,The Centre for the Analysis of Genome Evolution and Function, University of Toronto, Toronto, Ontario M5S 3B2, Canada
| | - Ji-Young Youn
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada.,Program in Molecular Medicine, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
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27
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Wittmer Y, Jami KM, Stowell RK, Le T, Hung I, Murray DT. Liquid Droplet Aging and Seeded Fibril Formation of the Cytotoxic Granule Associated RNA Binding Protein TIA1 Low Complexity Domain. J Am Chem Soc 2023; 145:1580-1592. [PMID: 36638831 PMCID: PMC9881004 DOI: 10.1021/jacs.2c08596] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Protein domains biased toward a few amino acid types are vital for the formation of biomolecular condensates in living cells. These membraneless compartments are formed by molecules exhibiting a range of molecular motions and structural order. Missense mutations increase condensate persistence lifetimes or structural order, properties that are thought to underlie pathological protein aggregation. In the context of stress granules associated with neurodegenerative diseases, this process involves the rigidification of protein liquid droplets into β-strand rich protein fibrils. Here, we characterize the molecular mechanism underlying the rigidification of liquid droplets for the low complexity domain of the Cytotoxic granule associated RNA binding protein TIA1 (TIA1) stress granule protein and the influence of a disease mutation linked to neurodegenerative diseases. A seeding procedure and solid state nuclear magnetic resonance measurements show that the low complexity domain converges on a β-strand rich fibril conformation composed of 21% of the sequence. Additional solid state nuclear magnetic resonance measurements and difference spectroscopy show that aged liquid droplets of wild type and a proline-to-leucine mutant low complexity domain are composed of fibril assemblies that are conformationally heterogeneous and structurally distinct from the seeded fibril preparation. Regarding low complexity domains, our data support the functional template-driven formation of conformationally homogeneous structures, that rigidification of liquid droplets into conformationally heterogenous structures promotes pathological interactions, and that the effect of disease mutations is more nuanced than increasing thermodynamic stability or increasing β-strand structure content.
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Affiliation(s)
- Yuuki Wittmer
- Department
of Chemistry, University of California Davis, Davis, California 95616, United States
| | - Khaled M. Jami
- Department
of Chemistry, University of California Davis, Davis, California 95616, United States
| | - Rachelle K. Stowell
- Department
of Chemistry, University of California Davis, Davis, California 95616, United States
| | - Truc Le
- Department
of Chemistry, University of California Davis, Davis, California 95616, United States
| | - Ivan Hung
- National
High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - Dylan T. Murray
- Department
of Chemistry, University of California Davis, Davis, California 95616, United States,
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28
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Mohanty P, Kapoor U, Sundaravadivelu Devarajan D, Phan TM, Rizuan A, Mittal J. Principles Governing the Phase Separation of Multidomain Proteins. Biochemistry 2022; 61:2443-2455. [PMID: 35802394 PMCID: PMC9669140 DOI: 10.1021/acs.biochem.2c00210] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A variety of membraneless organelles, often termed "biological condensates", play an important role in the regulation of cellular processes such as gene transcription, translation, and protein quality control. On the basis of experimental and theoretical investigations, liquid-liquid phase separation (LLPS) has been proposed as a possible mechanism for the origin of biological condensates. LLPS requires multivalent macromolecules that template the formation of long-range, intermolecular interaction networks and results in the formation of condensates with defined composition and material properties. Multivalent interactions driving LLPS exhibit a wide range of modes from highly stereospecific to nonspecific and involve both folded and disordered regions. Multidomain proteins serve as suitable macromolecules for promoting phase separation and achieving disparate functions due to their potential for multivalent interactions and regulation. Here, we aim to highlight the influence of the domain architecture and interdomain interactions on the phase separation of multidomain protein condensates. First, the general principles underlying these interactions are illustrated on the basis of examples of multidomain proteins that are predominantly associated with nucleic acid binding and protein quality control and contain both folded and disordered regions. Next, the examples showcase how LLPS properties of folded and disordered regions can be leveraged to engineer multidomain constructs that form condensates with the desired assembly and functional properties. Finally, we highlight the need for improvements in coarse-grained computational models that can provide molecular-level insights into multidomain protein condensates in conjunction with experimental efforts.
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Affiliation(s)
- Priyesh Mohanty
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843
| | - Utkarsh Kapoor
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843
| | | | - Tien Minh Phan
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843
| | - Azamat Rizuan
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843
| | - Jeetain Mittal
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843
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29
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Cao B, Qin J, Pan B, Qazi IH, Ye J, Fang Y, Zhou G. Oxidative Stress and Oocyte Cryopreservation: Recent Advances in Mitigation Strategies Involving Antioxidants. Cells 2022; 11:cells11223573. [PMID: 36429002 PMCID: PMC9688603 DOI: 10.3390/cells11223573] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/07/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022] Open
Abstract
Oocyte cryopreservation is widely used in assisted-reproductive technology and animal production. However, cryopreservation not only induces a massive accumulation of reactive oxygen species (ROS) in oocytes, but also leads to oxidative-stress-inflicted damage to mitochondria and the endoplasmic reticulum. These stresses lead to damage to the spindle, DNA, proteins, and lipids, ultimately reducing the developmental potential of oocytes both in vitro and in vivo. Although oocytes can mitigate oxidative stress via intrinsic antioxidant systems, the formation of ribonucleoprotein granules, mitophagy, and the cryopreservation-inflicted oxidative damage cannot be completely eliminated. Therefore, exogenous antioxidants such as melatonin and resveratrol are widely used in oocyte cryopreservation to reduce oxidative damage through direct or indirect scavenging of ROS. In this review, we discuss analysis of various oxidative stresses induced by oocyte cryopreservation, the impact of antioxidants against oxidative damage, and their underlying mechanisms. We hope that this literature review can provide a reference for improving the efficiency of oocyte cryopreservation.
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Affiliation(s)
- Beijia Cao
- Key Laboratory of Livestock and Poultry Multi-Omics, Ministry of Agriculture and Rural Affairs, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology (Institute of Animal Genetics and Breeding), Sichuan Agricultural University, Chengdu 611130, China
| | - Jianpeng Qin
- Key Laboratory of Livestock and Poultry Multi-Omics, Ministry of Agriculture and Rural Affairs, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology (Institute of Animal Genetics and Breeding), Sichuan Agricultural University, Chengdu 611130, China
| | - Bo Pan
- Key Laboratory of Livestock and Poultry Multi-Omics, Ministry of Agriculture and Rural Affairs, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology (Institute of Animal Genetics and Breeding), Sichuan Agricultural University, Chengdu 611130, China
| | - Izhar Hyder Qazi
- Department of Veterinary Anatomy, Histology, and Embryology, Shaheed Benazir Bhutto University of Veterinary and Animal Sciences, Sakrand 67210, Pakistan
| | - Jiangfeng Ye
- Key Laboratory of Livestock and Poultry Multi-Omics, Ministry of Agriculture and Rural Affairs, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology (Institute of Animal Genetics and Breeding), Sichuan Agricultural University, Chengdu 611130, China
| | - Yi Fang
- Jilin Provincial Key Laboratory of Grassland Farming, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China
- Correspondence: (Y.F.); (G.Z.); Tel.: +86-431-8554-2291 (Y.F.); +86-28-8629-1010 (G.Z.)
| | - Guangbin Zhou
- Key Laboratory of Livestock and Poultry Multi-Omics, Ministry of Agriculture and Rural Affairs, and Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology (Institute of Animal Genetics and Breeding), Sichuan Agricultural University, Chengdu 611130, China
- Correspondence: (Y.F.); (G.Z.); Tel.: +86-431-8554-2291 (Y.F.); +86-28-8629-1010 (G.Z.)
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Wen Y, Ma J. Phase separation drives the formation of biomolecular condensates in the immune system. Front Immunol 2022; 13:986589. [PMID: 36439121 PMCID: PMC9685520 DOI: 10.3389/fimmu.2022.986589] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 10/19/2022] [Indexed: 08/12/2023] Open
Abstract
When the external conditions change, such as the temperature or the pressure, the multi-component system sometimes separates into several phases with different components and structures, which is called phase separation. Increasing studies have shown that cells condense related biomolecules into independent compartments in order to carry out orderly and efficient biological reactions with the help of phase separation. Biomolecular condensates formed by phase separation play a significant role in a variety of cellular processes, including the control of signal transduction, the regulation of gene expression, and the stress response. In recent years, many phase separation events have been discovered in the immune response process. In this review, we provided a comprehensive and detailed overview of the role and mechanism of phase separation in the innate and adaptive immune responses, which will help the readers to appreciate the advance and importance of this field.
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Affiliation(s)
- Yuqing Wen
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
- Cancer Research Institute and School of Basic Medical Science, Central South University, Changsha, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Hunan Key Laboratory of Nonresolving Inflammation and Cancer, Hunan Key Laboratory of Cancer Metabolism, Changsha, China
| | - Jian Ma
- NHC Key Laboratory of Carcinogenesis, Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
- Cancer Research Institute and School of Basic Medical Science, Central South University, Changsha, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Hunan Key Laboratory of Nonresolving Inflammation and Cancer, Hunan Key Laboratory of Cancer Metabolism, Changsha, China
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Regulation of Polyhomeotic Condensates by Intrinsically Disordered Sequences That Affect Chromatin Binding. EPIGENOMES 2022; 6:epigenomes6040040. [PMID: 36412795 PMCID: PMC9680516 DOI: 10.3390/epigenomes6040040] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 10/30/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
Abstract
The Polycomb group (PcG) complex PRC1 localizes in the nucleus in condensed structures called Polycomb bodies. The PRC1 subunit Polyhomeotic (Ph) contains an oligomerizing sterile alpha motif (SAM) that is implicated in both PcG body formation and chromatin organization in Drosophila and mammalian cells. A truncated version of Ph containing the SAM (mini-Ph) forms phase-separated condensates with DNA or chromatin in vitro, suggesting that PcG bodies may form through SAM-driven phase separation. In cells, Ph forms multiple small condensates, while mini-Ph typically forms a single large nuclear condensate. We therefore hypothesized that sequences outside of mini-Ph, which are predicted to be intrinsically disordered, are required for proper condensate formation. We identified three distinct low-complexity regions in Ph based on sequence composition. We systematically tested the role of each of these sequences in Ph condensates using live imaging of transfected Drosophila S2 cells. Each sequence uniquely affected Ph SAM-dependent condensate size, number, and morphology, but the most dramatic effects occurred when the central, glutamine-rich intrinsically disordered region (IDR) was removed, which resulted in large Ph condensates. Like mini-Ph condensates, condensates lacking the glutamine-rich IDR excluded chromatin. Chromatin fractionation experiments indicated that the removal of the glutamine-rich IDR reduced chromatin binding and that the removal of either of the other IDRs increased chromatin binding. Our data suggest that all three IDRs, and functional interactions among them, regulate Ph condensate size and number. Our results can be explained by a model in which tight chromatin binding by Ph IDRs antagonizes Ph SAM-driven phase separation. Our observations highlight the complexity of regulation of biological condensates housed in single proteins.
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Global profiling of arginine dimethylation in regulating protein phase separation by a steric effect-based chemical-enrichment method. Proc Natl Acad Sci U S A 2022; 119:e2205255119. [PMID: 36256816 PMCID: PMC9618127 DOI: 10.1073/pnas.2205255119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Protein arginine methylation plays an important role in regulating protein functions in different cellular processes, and its dysregulation may lead to a variety of human diseases. Recently, arginine methylation was found to be involved in modulating protein liquid-liquid phase separation (LLPS), which drives the formation of different membraneless organelles (MLOs). Here, we developed a steric effect-based chemical-enrichment method (SECEM) coupled with liquid chromatography-tandem mass spectrometry to analyze arginine dimethylation (DMA) at the proteome level. We revealed by SECEM that, in mammalian cells, the DMA sites occurring in the RG/RGG motifs are preferentially enriched within the proteins identified in different MLOs, especially stress granules (SGs). Notably, global decrease of protein arginine methylation severely impairs the dynamic assembly and disassembly of SGs. By further profiling the dynamic change of DMA upon SG formation by SECEM, we identified that the most dramatic change of DMA occurs at multiple sites of RG/RGG-rich regions from several key SG-contained proteins, including G3BP1, FUS, hnRNPA1, and KHDRBS1. Moreover, both in vitro arginine methylation and mutation of the identified DMA sites significantly impair LLPS capability of the four different RG/RGG-rich regions. Overall, we provide a global profiling of the dynamic changes of protein DMA in the mammalian cells under different stress conditions by SECEM and reveal the important role of DMA in regulating protein LLPS and SG dynamics.
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Kamal M, Tokmakjian L, Knox J, Mastrangelo P, Ji J, Cai H, Wojciechowski JW, Hughes MP, Takács K, Chu X, Pei J, Grolmusz V, Kotulska M, Forman-Kay JD, Roy PJ. A spatiotemporal reconstruction of the C. elegans pharyngeal cuticle reveals a structure rich in phase-separating proteins. eLife 2022; 11:e79396. [PMID: 36259463 PMCID: PMC9629831 DOI: 10.7554/elife.79396] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 10/11/2022] [Indexed: 11/19/2022] Open
Abstract
How the cuticles of the roughly 4.5 million species of ecdysozoan animals are constructed is not well understood. Here, we systematically mine gene expression datasets to uncover the spatiotemporal blueprint for how the chitin-based pharyngeal cuticle of the nematode Caenorhabditis elegans is built. We demonstrate that the blueprint correctly predicts expression patterns and functional relevance to cuticle development. We find that as larvae prepare to molt, catabolic enzymes are upregulated and the genes that encode chitin synthase, chitin cross-linkers, and homologs of amyloid regulators subsequently peak in expression. Forty-eight percent of the gene products secreted during the molt are predicted to be intrinsically disordered proteins (IDPs), many of which belong to four distinct families whose transcripts are expressed in overlapping waves. These include the IDPAs, IDPBs, and IDPCs, which are introduced for the first time here. All four families have sequence properties that drive phase separation and we demonstrate phase separation for one exemplar in vitro. This systematic analysis represents the first blueprint for cuticle construction and highlights the massive contribution that phase-separating materials make to the structure.
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Affiliation(s)
- Muntasir Kamal
- Department of Molecular Genetics, University of TorontoTorontoCanada
- The Donnelly Centre for Cellular and Biomolecular Research, University of TorontoTorontoCanada
| | - Levon Tokmakjian
- The Donnelly Centre for Cellular and Biomolecular Research, University of TorontoTorontoCanada
- Department of Pharmacology and Toxicology, University of TorontoTorontoCanada
| | - Jessica Knox
- Department of Molecular Genetics, University of TorontoTorontoCanada
- The Donnelly Centre for Cellular and Biomolecular Research, University of TorontoTorontoCanada
| | - Peter Mastrangelo
- Department of Molecular Genetics, University of TorontoTorontoCanada
- The Donnelly Centre for Cellular and Biomolecular Research, University of TorontoTorontoCanada
| | - Jingxiu Ji
- Department of Molecular Genetics, University of TorontoTorontoCanada
- The Donnelly Centre for Cellular and Biomolecular Research, University of TorontoTorontoCanada
| | - Hao Cai
- Molecular Medicine Program, The Hospital for Sick ChildrenTorontoCanada
| | - Jakub W Wojciechowski
- Wroclaw University of Science and Technology, Faculty of Fundamental Problems of Technology, Department of Biomedical EngineeringWroclawPoland
| | - Michael P Hughes
- Department of Cell and Molecular Biology, St. Jude Children’s Research HospitalMemphisUnited States
| | - Kristóf Takács
- PIT Bioinformatics Group, Institute of Mathematics, Eötvös UniversityBudapestHungary
| | - Xiaoquan Chu
- Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking UniversityBeijingChina
| | - Jianfeng Pei
- Department of Computer Science and Technology, Tsinghua UniversityBeijingChina
| | - Vince Grolmusz
- PIT Bioinformatics Group, Institute of Mathematics, Eötvös UniversityBudapestHungary
| | - Malgorzata Kotulska
- Wroclaw University of Science and Technology, Faculty of Fundamental Problems of Technology, Department of Biomedical EngineeringWroclawPoland
| | - Julie Deborah Forman-Kay
- Molecular Medicine Program, The Hospital for Sick ChildrenTorontoCanada
- Department of Biochemistry, University of TorontoTorontoCanada
| | - Peter J Roy
- Department of Molecular Genetics, University of TorontoTorontoCanada
- The Donnelly Centre for Cellular and Biomolecular Research, University of TorontoTorontoCanada
- Department of Pharmacology and Toxicology, University of TorontoTorontoCanada
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34
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Cai H, Vernon RM, Forman-Kay JD. An Interpretable Machine-Learning Algorithm to Predict Disordered Protein Phase Separation Based on Biophysical Interactions. Biomolecules 2022; 12:biom12081131. [PMID: 36009025 PMCID: PMC9405563 DOI: 10.3390/biom12081131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 11/21/2022] Open
Abstract
Protein phase separation is increasingly understood to be an important mechanism of biological organization and biomaterial formation. Intrinsically disordered protein regions (IDRs) are often significant drivers of protein phase separation. A number of protein phase-separation-prediction algorithms are available, with many being specific for particular classes of proteins and others providing results that are not amenable to the interpretation of the contributing biophysical interactions. Here, we describe LLPhyScore, a new predictor of IDR-driven phase separation, based on a broad set of physical interactions or features. LLPhyScore uses sequence-based statistics from the RCSB PDB database of folded structures for these interactions, and is trained on a manually curated set of phase-separation-driving proteins with different negative training sets including the PDB and human proteome. Competitive training for a variety of physical chemical interactions shows the greatest contribution of solvent contacts, disorder, hydrogen bonds, pi–pi contacts, and kinked beta-structures to the score, with electrostatics, cation–pi contacts, and the absence of a helical secondary structure also contributing. LLPhyScore has strong phase-separation-prediction recall statistics and enables a breakdown of the contribution from each physical feature to a sequence’s phase-separation propensity, while recognizing the interdependence of many of these features. The tool should be a valuable resource for guiding experiments and providing hypotheses for protein function in normal and pathological states, as well as for understanding how specificity emerges in defining individual biomolecular condensates.
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Affiliation(s)
- Hao Cai
- Molecular Medicine Program, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Robert M. Vernon
- Molecular Medicine Program, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Julie D. Forman-Kay
- Molecular Medicine Program, Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON M5S 1A8, Canada
- Correspondence:
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35
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Ng WS, Sielaff H, Zhao ZW. Phase Separation-Mediated Chromatin Organization and Dynamics: From Imaging-Based Quantitative Characterizations to Functional Implications. Int J Mol Sci 2022; 23:ijms23148039. [PMID: 35887384 PMCID: PMC9316379 DOI: 10.3390/ijms23148039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 12/14/2022] Open
Abstract
As an effective and versatile strategy to compartmentalize cellular components without the need for lipid membranes, phase separation has been found to underpin a wide range of intranuclear processes, particularly those involving chromatin. Many of the unique physico-chemical properties of chromatin-based phase condensates are harnessed by the cell to accomplish complex regulatory functions in a spatially and temporally controlled manner. Here, we survey key recent findings on the mechanistic roles of phase separation in regulating the organization and dynamics of chromatin-based molecular processes across length scales, packing states and intranuclear functions, with a particular emphasis on quantitative characterizations of these condensates enabled by advanced imaging-based approaches. By illuminating the complex interplay between chromatin and various chromatin-interacting molecular species mediated by phase separation, this review sheds light on an emerging multi-scale, multi-modal and multi-faceted landscape that hierarchically regulates the genome within the highly crowded and dynamic nuclear space. Moreover, deficiencies in existing studies also highlight the need for mechanism-specific criteria and multi-parametric approaches for the characterization of chromatin-based phase separation using complementary techniques and call for greater efforts to correlate the quantitative features of these condensates with their functional consequences in close-to-native cellular contexts.
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Affiliation(s)
- Woei Shyuan Ng
- Department of Chemistry, Faculty of Science, National University of Singapore, Singapore 119543, Singapore; (W.S.N.); (H.S.)
- Centre for BioImaging Sciences (CBIS), Faculty of Science, National University of Singapore, Singapore 117557, Singapore
| | - Hendrik Sielaff
- Department of Chemistry, Faculty of Science, National University of Singapore, Singapore 119543, Singapore; (W.S.N.); (H.S.)
- Centre for BioImaging Sciences (CBIS), Faculty of Science, National University of Singapore, Singapore 117557, Singapore
| | - Ziqing Winston Zhao
- Department of Chemistry, Faculty of Science, National University of Singapore, Singapore 119543, Singapore; (W.S.N.); (H.S.)
- Centre for BioImaging Sciences (CBIS), Faculty of Science, National University of Singapore, Singapore 117557, Singapore
- Mechanobiology Institute (MBI), National University of Singapore, Singapore 117411, Singapore
- Correspondence:
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36
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Kedia S, Aghanoori MR, Burns KML, Subha M, Williams L, Wen P, Kopp D, Erickson SL, Harvey EM, Chen X, Hua M, Perez JU, Ishraque F, Yang G. Ubiquitination and deubiquitination of 4E-T regulate neural progenitor cell maintenance and neurogenesis by controlling P-body formation. Cell Rep 2022; 40:111070. [PMID: 35830814 DOI: 10.1016/j.celrep.2022.111070] [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: 09/13/2021] [Revised: 05/17/2022] [Accepted: 06/14/2022] [Indexed: 11/19/2022] Open
Abstract
During embryogenesis, neural stem/progenitor cells (NPCs) proliferate and differentiate to form brain tissues. Here, we show that in the developing murine cerebral cortex, the balance between the NPC maintenance and differentiation is coordinated by ubiquitin signals that control the formation of processing bodies (P-bodies), cytoplasmic membraneless organelles critical for cell state regulation. We find that the deubiquitinase Otud4 and the E3 ligase Trim56 counter-regulate the ubiquitination status of a core P-body protein 4E-T to orchestrate the assembly of P-bodies in NPCs. Aberrant induction of 4E-T ubiquitination promotes P-body assembly in NPCs and causes a delay in their cell cycle progression and differentiation. In contrast, loss of 4E-T ubiquitination abrogates P-bodies and results in premature neurogenesis. Thus, our results reveal a critical role of ubiquitin-dependent regulation of P-body formation in NPC maintenance and neurogenesis during brain development.
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Affiliation(s)
- Shreeya Kedia
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada; Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada
| | - Mohamad-Reza Aghanoori
- Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada; Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Kaylan M L Burns
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada; Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada
| | - Maneesha Subha
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada; Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada
| | - Laura Williams
- Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada; Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Pengqiang Wen
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada; Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada
| | - Drayden Kopp
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada; Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada
| | - Sarah L Erickson
- Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada; Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Emily M Harvey
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada; Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada
| | - Xin Chen
- Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada; Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Michelle Hua
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada; Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada
| | - Jose Uriel Perez
- Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada
| | - Fatin Ishraque
- Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada
| | - Guang Yang
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada; Alberta Children's Hospital Research Institute, Calgary, AB T2N 4N1, Canada; Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada; Owerko Centre, ACHRI, Calgary, AB T2N 4N1, Canada.
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Regulating Phase Transition in Neurodegenerative Diseases by Nuclear Import Receptors. BIOLOGY 2022; 11:biology11071009. [PMID: 36101390 PMCID: PMC9311884 DOI: 10.3390/biology11071009] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/12/2022] [Accepted: 06/16/2022] [Indexed: 11/17/2022]
Abstract
RNA-binding proteins (RBPs) with a low-complexity prion-like domain (PLD) can undergo aberrant phase transitions and have been implicated in neurodegenerative diseases such as ALS and FTD. Several nuclear RBPs mislocalize to cytoplasmic inclusions in disease conditions. Impairment in nucleocytoplasmic transport is another major event observed in ageing and in neurodegenerative disorders. Nuclear import receptors (NIRs) regulate the nucleocytoplasmic transport of different RBPs bearing a nuclear localization signal by restoring their nuclear localization. NIRs can also specifically dissolve or prevent the aggregation and liquid–liquid phase separation of wild-type or disease-linked mutant RBPs, due to their chaperoning activity. This review focuses on the LLPS of intrinsically disordered proteins and the role of NIRs in regulating LLPS in neurodegeneration. This review also discusses the implication of NIRs as therapeutic agents in neurogenerative diseases.
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Multivalent interactions with RNA drive recruitment and dynamics in biomolecular condensates in Xenopus oocytes. iScience 2022; 25:104811. [PMID: 35982794 PMCID: PMC9379569 DOI: 10.1016/j.isci.2022.104811] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/24/2022] [Accepted: 07/16/2022] [Indexed: 11/22/2022] Open
Abstract
RNA localization and biomolecular condensate formation are key biological strategies for organizing the cytoplasm and generating cellular polarity. In Xenopus oocytes, RNAs required for germ layer patterning localize in biomolecular condensates, termed Localization bodies (L-bodies). Here, we have used an L-body RNA-binding protein, PTBP3, to test the role of RNA–protein interactions in regulating the biophysical characteristics of L-bodies in vivo and PTBP3–RNA condensates in vitro. Our results reveal that RNA–protein interactions drive recruitment of PTBP3 and localized RNA to L-bodies and that multivalent interactions tune the dynamics of the PTBP3 after localization. In a concentration-dependent manner, RNA becomes non-dynamic and interactions with the RNA determine PTBP3 dynamics within these biomolecular condensates in vivo and in vitro. Importantly, RNA, and not protein, is required for maintenance of the PTBP3–RNA condensates in vitro, pointing to a model where RNA serves as a non-dynamic substructure in these condensates. RNA–protein interactions drive recruitment of both RNA and protein to L-bodies RNA is non-dynamic in both L-bodies and in vitro condensates Multivalent interactions with RNA tune protein dynamics both in vivo and in vitro RNA, but not protein, is required for maintenance of the in vitro condensates
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Jeon P, Ham HJ, Park S, Lee JA. Regulation of Cellular Ribonucleoprotein Granules: From Assembly to Degradation via Post-translational Modification. Cells 2022; 11:cells11132063. [PMID: 35805146 PMCID: PMC9265587 DOI: 10.3390/cells11132063] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/09/2022] [Accepted: 06/24/2022] [Indexed: 02/04/2023] Open
Abstract
Cells possess membraneless ribonucleoprotein (RNP) granules, including stress granules, processing bodies, Cajal bodies, or paraspeckles, that play physiological or pathological roles. RNP granules contain RNA and numerous RNA-binding proteins, transiently formed through the liquid–liquid phase separation. The assembly or disassembly of numerous RNP granules is strongly controlled to maintain their homeostasis and perform their cellular functions properly. Normal RNA granules are reversibly assembled, whereas abnormal RNP granules accumulate and associate with various neurodegenerative diseases. This review summarizes current studies on the physiological or pathological roles of post-translational modifications of various cellular RNP granules and discusses the therapeutic methods in curing diseases related to abnormal RNP granules by autophagy.
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40
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Screening membraneless organelle participants with machine-learning models that integrate multimodal features. Proc Natl Acad Sci U S A 2022; 119:e2115369119. [PMID: 35687670 PMCID: PMC9214545 DOI: 10.1073/pnas.2115369119] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Protein self-assembly is one of the formation mechanisms of biomolecular condensates. However, most phase-separating systems (PS) demand multiple partners in biological conditions. In this study, we divided PS proteins into two groups according to the mechanism by which they undergo PS: PS-Self proteins can self-assemble spontaneously to form droplets, while PS-Part proteins interact with partners to undergo PS. Analysis of the amino acid composition revealed differences in the sequence pattern between the two protein groups. Existing PS predictors, when evaluated on two test protein sets, preferentially predicted self-assembling proteins. Thus, a comprehensive predictor is required. Herein, we propose that properties other than sequence composition can provide crucial information in screening PS proteins. By incorporating phosphorylation frequencies and immunofluorescence image-based droplet-forming propensity with other PS-related features, we built two independent machine-learning models to separately predict the two protein categories. Results of independent testing suggested the superiority of integrating multimodal features. We performed experimental verification on the top-scored proteins DHX9, Ki-67, and NIFK. Their PS behavior in vitro revealed the effectiveness of our models in PS prediction. Further validation on the proteome of membraneless organelles confirmed the ability of our models to identify PS-Part proteins. We implemented a web server named PhaSePred (http://predict.phasep.pro/) that incorporates our two models together with representative PS predictors. PhaSePred displays proteome-level quantiles of different features, thus profiling PS propensity and providing crucial information for identification of candidate proteins.
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41
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Liu H, Zhang X, Zhao Z, Zhu H, Li D, Yang Y, Zhao W, Zhang F, Wang Y, Zhu L, Ding Z, Li X. CNST is Characteristic of Leukemia Stem Cells and is Associated With Poor Prognosis in AML. Front Pharmacol 2022; 13:888243. [PMID: 35662693 PMCID: PMC9157791 DOI: 10.3389/fphar.2022.888243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 03/28/2022] [Indexed: 11/30/2022] Open
Abstract
Consortin (CNST) is a protein located on the trans-Golgi network that can target transmembrane proteins to the plasma membrane. Although CNST was discovered more than 10 years ago, there are still not enough studies on its function. During our search for possible new acute myeloid leukemia (AML) markers, we found that CNST was overexpressed in almost all patients with AML. By analyzing profiling data from public databases, we found that CNST expression inversely correlated with overall survival among AML patients. There was a great variation in CNST expression among different subtypes of AML, and the expression was the highest in the t(8,21) subtype, which was probably due to the direct regulation of CNST transcription by RUNX1-RUNX1T1. In addition, we analyzed the expression of CNST in different cells of the hematopoietic system. We found that CNST was associated with the low differentiation degrees of hematopoietic cells and had the highest expression level in leukemia stem cells (LSCs). Finally, we analyzed the CNST-related gene network and found that the genes negatively correlated with CNST are involved in various immune-related pathways, which indicates that CNST is likely related to immune evasion, LSC niche retention, and assembly of stress granules. In conclusion, our study suggests that CNST has the potential to be a diagnostic and prognostic biomarker for AML.
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Affiliation(s)
- Haoyu Liu
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Advanced Medical Research Institute, Shandong University, Qingdao, China
| | - Xu Zhang
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Advanced Medical Research Institute, Shandong University, Qingdao, China
| | - Ziyan Zhao
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Advanced Medical Research Institute, Shandong University, Qingdao, China
| | - Hongying Zhu
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Advanced Medical Research Institute, Shandong University, Qingdao, China
| | - Danyang Li
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Advanced Medical Research Institute, Shandong University, Qingdao, China.,Rehabilitation Center, Qilu Hospital, Cheelo College of Medicine, Shandong University, Jinan, China
| | - Yang Yang
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Advanced Medical Research Institute, Shandong University, Qingdao, China.,School of Pharmacy, Binzhou Medical University, Yantai, China
| | - Wenbo Zhao
- Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Fei Zhang
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Advanced Medical Research Institute, Shandong University, Qingdao, China
| | - Yuefeng Wang
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Advanced Medical Research Institute, Shandong University, Qingdao, China
| | - Lina Zhu
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Advanced Medical Research Institute, Shandong University, Qingdao, China
| | - Zewen Ding
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Xiangzhi Li
- Shandong Provincial Key Laboratory of Animal Cell and Developmental Biology, School of Life Sciences, Advanced Medical Research Institute, Shandong University, Qingdao, China
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Linsenmeier M, Hondele M, Grigolato F, Secchi E, Weis K, Arosio P. Dynamic arrest and aging of biomolecular condensates are modulated by low-complexity domains, RNA and biochemical activity. Nat Commun 2022; 13:3030. [PMID: 35641495 PMCID: PMC9156751 DOI: 10.1038/s41467-022-30521-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 04/27/2022] [Indexed: 11/18/2022] Open
Abstract
Biomolecular condensates require suitable control of material properties for their function. Here we apply Differential Dynamic Microscopy (DDM) to probe the material properties of an in vitro model of processing bodies consisting of out-of-equilibrium condensates formed by the DEAD-box ATPase Dhh1 in the presence of ATP and RNA. By applying this single-droplet technique we show that condensates within the same population exhibit a distribution of material properties, which are regulated on several levels. Removal of the low-complexity domains (LCDs) of the protein decreases the fluidity of the condensates. Structured RNA leads to a larger fraction of dynamically arrested condensates with respect to unstructured polyuridylic acid (polyU). Promotion of the enzymatic ATPase activity of Dhh1 reduces aging of the condensates and the formation of arrested structures, indicating that biochemical activity and material turnover can maintain fluid-like properties over time.
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Affiliation(s)
- Miriam Linsenmeier
- Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, Swiss Federal Institute of Technology, 8093, Zurich, Switzerland
| | - Maria Hondele
- Department of Biology, Institute for Biochemistry, Swiss Federal Institute of Technology, 8093, Zurich, Switzerland
- Biozentrum, Center for Molecular Life Sciences, University of Basel, 4056, Basel, Switzerland
| | - Fulvio Grigolato
- Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, Swiss Federal Institute of Technology, 8093, Zurich, Switzerland
| | - Eleonora Secchi
- Department of Civil, Environmental and Geomatic Engineering, Swiss Federal Institute of Technology, 8093, Zurich, Switzerland
| | - Karsten Weis
- Department of Biology, Institute for Biochemistry, Swiss Federal Institute of Technology, 8093, Zurich, Switzerland.
| | - Paolo Arosio
- Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, Swiss Federal Institute of Technology, 8093, Zurich, Switzerland.
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Enenkel C, Kang RW, Wilfling F, Ernst OP. Intracellular localization of the proteasome in response to stress conditions. J Biol Chem 2022; 298:102083. [PMID: 35636514 PMCID: PMC9218506 DOI: 10.1016/j.jbc.2022.102083] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 05/13/2022] [Accepted: 05/16/2022] [Indexed: 12/15/2022] Open
Abstract
The ubiquitin–proteasome system fulfills an essential role in regulating protein homeostasis by spatially and temporally controlling proteolysis in an ATP- and ubiquitin-dependent manner. However, the localization of proteasomes is highly variable under diverse cellular conditions. In yeast, newly synthesized proteasomes are primarily localized to the nucleus during cell proliferation. Yeast proteasomes are transported into the nucleus through the nuclear pore either as immature subcomplexes or as mature enzymes via adapter proteins Sts1 and Blm10, while in mammalian cells, postmitotic uptake of proteasomes into the nucleus is mediated by AKIRIN2, an adapter protein essentially required for nuclear protein degradation. Stressful growth conditions and the reversible halt of proliferation, that is quiescence, are associated with a decline in ATP and the reorganization of proteasome localization. Cellular stress leads to proteasome accumulation in membraneless granules either in the nucleus or in the cytoplasm. In quiescence, yeast proteasomes are sequestered in an ubiquitin-dependent manner into motile and reversible proteasome storage granules in the cytoplasm. In cancer cells, upon amino acid deprivation, heat shock, osmotic stress, oxidative stress, or the inhibition of either proteasome activity or nuclear export, reversible proteasome foci containing polyubiquitinated substrates are formed by liquid–liquid phase separation in the nucleus. In this review, we summarize recent literature revealing new links between nuclear transport, ubiquitin signaling, and the intracellular organization of proteasomes during cellular stress conditions.
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Affiliation(s)
- Cordula Enenkel
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
| | - Ryu Won Kang
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Florian Wilfling
- Mechanisms of Cellular Quality Control, Max-Planck-Institute of Biophysics, Frankfurt, Germany
| | - Oliver P Ernst
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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44
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Krause LJ, Herrera MG, Winklhofer KF. The Role of Ubiquitin in Regulating Stress Granule Dynamics. Front Physiol 2022; 13:910759. [PMID: 35694405 PMCID: PMC9174786 DOI: 10.3389/fphys.2022.910759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 05/09/2022] [Indexed: 11/30/2022] Open
Abstract
Stress granules (SGs) are dynamic, reversible biomolecular condensates, which assemble in the cytoplasm of eukaryotic cells under various stress conditions. Formation of SGs typically occurs upon stress-induced translational arrest and polysome disassembly. The increase in cytoplasmic mRNAs triggers the formation of a protein-RNA network that undergoes liquid-liquid phase separation when a critical interaction threshold has been reached. This adaptive stress response allows a transient shutdown of several cellular processes until the stress is removed. During the recovery from stress, SGs disassemble to re-establish cellular activities. Persistent stress and disease-related mutations in SG components favor the formation of aberrant SGs that are impaired in disassembly and prone to aggregation. Recently, posttranslational modifications of SG components have been identified as major regulators of SG dynamics. Here, we summarize new insights into the role of ubiquitination in affecting SG dynamics and clearance and discuss implications for neurodegenerative diseases linked to aberrant SG formation.
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Affiliation(s)
- Laura J. Krause
- Department of Molecular Cell Biology, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
- RESOLV Cluster of Excellence, Ruhr University Bochum, Bochum, Germany
| | - Maria G. Herrera
- Department of Molecular Cell Biology, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
| | - Konstanze F. Winklhofer
- Department of Molecular Cell Biology, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
- RESOLV Cluster of Excellence, Ruhr University Bochum, Bochum, Germany
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45
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Pushpalatha KV, Solyga M, Nakamura A, Besse F. RNP components condense into repressive RNP granules in the aging brain. Nat Commun 2022; 13:2782. [PMID: 35589695 PMCID: PMC9120078 DOI: 10.1038/s41467-022-30066-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 04/11/2022] [Indexed: 12/21/2022] Open
Abstract
Cytoplasmic RNP condensates enriched in mRNAs and proteins are found in various cell types and associated with both buffering and regulatory functions. While a clear link has been established between accumulation of aberrant RNP aggregates and progression of aging-related neurodegenerative diseases, the impact of physiological aging on neuronal RNP condensates has never been explored. Through high-resolution imaging, we uncover that RNP components progressively cluster into large yet dynamic granules in the aging Drosophila brain. We further show that age-dependent clustering is caused by an increase in the stoichiometry of the conserved helicase Me31B/DDX6, and requires PKA kinase activity. Finally, our functional analysis reveals that mRNA species recruited to RNP condensates upon aging exhibit age-dependent translational repression, indicating that co-clustering of selected mRNAs and translation regulators into repressive condensates may contribute to the specific post-transcriptional changes in gene expression observed in the course of aging. Aberrant RNA condensates are a hallmark of age-related neurodegenerative diseases. Here, the authors show that RNA condensation increases in aging Drosophila brains, triggering translation repression.
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Affiliation(s)
| | - Mathilde Solyga
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, Nice, France
| | - Akira Nakamura
- Department of Germline Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan.,Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan
| | - Florence Besse
- Université Côte d'Azur, CNRS, Inserm, Institut de Biologie Valrose, Nice, France.
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Brodin L, Milovanovic D, Rizzoli SO, Shupliakov O. α-Synuclein in the Synaptic Vesicle Liquid Phase: Active Player or Passive Bystander? Front Mol Biosci 2022; 9:891508. [PMID: 35664678 PMCID: PMC9159372 DOI: 10.3389/fmolb.2022.891508] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 04/26/2022] [Indexed: 12/15/2022] Open
Abstract
The protein α-synuclein, which is well-known for its links to Parkinson’s Disease, is associated with synaptic vesicles (SVs) in nerve terminals. Despite intensive studies, its precise physiological function remains elusive. Accumulating evidence indicates that liquid-liquid phase separation takes part in the assembly and/or maintenance of different synaptic compartments. The current review discusses recent data suggesting α-synuclein as a component of the SV liquid phase. We also consider possible implications of these data for disease.
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Affiliation(s)
- Lennart Brodin
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
- *Correspondence: Lennart Brodin, ; Oleg Shupliakov,
| | - Dragomir Milovanovic
- Laboratory of Molecular Neuroscience, German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
| | - Silvio O. Rizzoli
- Institute of Neuro- and Sensory Physiology, University Medical Center Göttingen, Göttingen, Germany
| | - Oleg Shupliakov
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Institute of Translational Biomedicine, St. Petersburg University, St. Petersburg, Russia
- *Correspondence: Lennart Brodin, ; Oleg Shupliakov,
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Navarro AM, Orti F, Martínez-Pérez E, Alonso M, Simonetti FL, Iserte JA, Marino-Buslje C. DisPhaseDB: an integrative database of diseases related variations in liquid-liquid phase separation proteins. Comput Struct Biotechnol J 2022; 20:2551-2557. [PMID: 35685370 PMCID: PMC9156858 DOI: 10.1016/j.csbj.2022.05.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 05/03/2022] [Accepted: 05/03/2022] [Indexed: 11/29/2022] Open
Abstract
Phase separation proteins involved in membraneless organelles are increasingly implicated in several complex human diseases. DisPhaseDB integrates ten repositories for analyzing clinically relevant mutations in phase separation proteins. Contains over a million disease-related mutations mapped onto the protein sequences along with extensive metadata. It is a comprehensive meta-database, implemented in an user-friendly web with visualization tools and downloadable datasets. DisPhaseDB will contribute deciphering still not fully understood human disease mechanisms under the lens of phase separation.
Motivation Proteins involved in liquid–liquid phase separation (LLPS) and membraneless organelles (MLOs) are recognized to be decisive for many biological processes and also responsible for several diseases. The recent explosion of research in the area still lacks tools for the analysis and data integration among different repositories. Currently, there is not a comprehensive and dedicated database that collects all disease-related variations in combination with the protein location, biological role in the MLO, and all the metadata available for each protein and disease. Disease-related protein variants and additional features are dispersed and the user has to navigate many databases, with a different focus, formats, and often not user friendly. Results We present DisPhaseDB, a database dedicated to disease-related variants of liquid–liquid phase separation proteins. It integrates 10 databases, contains 5,741 proteins, 1,660,059 variants, and 4,051 disease terms. It also offers intuitive navigation and an informative display. It constitutes a pivotal starting point for further analysis, encouraging the development of new computational tools. The database is freely available at http://disphasedb.leloir.org.ar.
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Cañonero L, Pautasso C, Galello F, Sigaut L, Pietrasanta L, Arroyo J, Bermúdez-Moretti M, Portela P, Rossi S. Heat stress regulates the expression of TPK1 gene at transcriptional and post-transcriptional levels in Saccharomyces cerevisiae. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2022; 1869:119209. [PMID: 34999138 DOI: 10.1016/j.bbamcr.2021.119209] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 12/16/2021] [Accepted: 12/28/2021] [Indexed: 12/11/2022]
Abstract
In Saccharomyces cerevisiae cAMP regulates different cellular processes through PKA. The specificity of the response of the cAMP-PKA pathway is highly regulated. Here we address the mechanism through which the cAMP-PKA pathway mediates its response to heat shock and thermal adaptation in yeast. PKA holoenzyme is composed of a regulatory subunit dimer (Bcy1) and two catalytic subunits (Tpk1, Tpk2, or Tpk3). PKA subunits are differentially expressed under certain growth conditions. Here we demonstrate the increased abundance and half-life of TPK1 mRNA and the assembly of this mRNA in cytoplasmic foci during heat shock at 37 °C. The resistance of the foci to cycloheximide-induced disassembly along with the polysome profiling analysis suggest that TPK1 mRNA is impaired for entry into translation. TPK1 expression was also evaluated during a recurrent heat shock and thermal adaptation. Tpk1 protein level is significantly increased during the recovery periods. The crosstalk of cAMP-PKA pathway and CWI signalling was also studied. Wsc3 sensor and some components of the CWI pathway are necessary for the TPK1 expression upon heat shock. The assembly in foci upon thermal stress depends on Wsc3. Tpk1 expression is lower in a wsc3∆ mutant than in WT strain during thermal adaptation and thus the PKA levels are also lower. An increase in Tpk1 abundance in the PKA holoenzyme in response to heat shock is presented, suggesting that a recurrent stress enhanced the fitness for the coming favourable conditions. Therefore, the regulation of TPK1 expression by thermal stress contributes to the specificity of cAMP-PKA signalling.
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Affiliation(s)
- Luciana Cañonero
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento Química Biológica, Buenos Aires, Argentina; CONICET Universidad de Buenos Aires, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina
| | - Constanza Pautasso
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento Química Biológica, Buenos Aires, Argentina; CONICET Universidad de Buenos Aires, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina
| | - Fiorella Galello
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento Química Biológica, Buenos Aires, Argentina; CONICET Universidad de Buenos Aires, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina
| | - Lorena Sigaut
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento Física, Buenos Aires, Argentina; CONICET Universidad de Buenos Aires, Instituto de Física de Buenos Aires (IFIBA), Buenos Aires, Argentina
| | - Lia Pietrasanta
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento Física, Buenos Aires, Argentina; CONICET Universidad de Buenos Aires, Instituto de Física de Buenos Aires (IFIBA), Buenos Aires, Argentina
| | - Javier Arroyo
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad Complutense de Madrid, IRYCIS, Madrid, Spain
| | - Mariana Bermúdez-Moretti
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento Química Biológica, Buenos Aires, Argentina; CONICET Universidad de Buenos Aires, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina
| | - Paula Portela
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento Química Biológica, Buenos Aires, Argentina; CONICET Universidad de Buenos Aires, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina
| | - Silvia Rossi
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento Química Biológica, Buenos Aires, Argentina; CONICET Universidad de Buenos Aires, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN), Buenos Aires, Argentina.
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Role of the Ubiquitin System in Stress Granule Metabolism. Int J Mol Sci 2022; 23:ijms23073624. [PMID: 35408984 PMCID: PMC8999021 DOI: 10.3390/ijms23073624] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 03/24/2022] [Accepted: 03/25/2022] [Indexed: 02/01/2023] Open
Abstract
Eukaryotic cells react to various stress conditions with the rapid formation of membrane-less organelles called stress granules (SGs). SGs form by multivalent interactions between RNAs and RNA-binding proteins and are believed to protect stalled translation initiation complexes from stress-induced degradation. SGs contain hundreds of different mRNAs and proteins, and their assembly and disassembly are tightly controlled by post-translational modifications. The ubiquitin system, which mediates the covalent modification of target proteins with the small protein ubiquitin (‘ubiquitylation’), has been implicated in different aspects of SG metabolism, but specific functions in SG turnover have only recently emerged. Here, we summarize the evidence for the presence of ubiquitylated proteins at SGs, review the functions of different components of the ubiquitin system in SG formation and clearance, and discuss the link between perturbed SG clearance and the pathogenesis of neurodegenerative disorders. We conclude that the ubiquitin system plays an important, medically relevant role in SG biology.
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50
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Hanselmann RG, Welter C. Origin of Cancer: Cell work is the Key to Understanding Cancer Initiation and Progression. Front Cell Dev Biol 2022; 10:787995. [PMID: 35300431 PMCID: PMC8921603 DOI: 10.3389/fcell.2022.787995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 01/31/2022] [Indexed: 11/16/2022] Open
Abstract
The cell is the smallest unit of life. It is a structure that maintains order through self-organization, characterized by a high level of dynamism, which in turn is characterized by work. For this work to take place, a continuous high flow of energy is necessary. However, a focused view of the physical relationship between energy and work is inadequate for describing complex biological/medical mechanisms or systems. In this review, we try to make a connection between the fundamental laws of physics and the mechanisms and functions of biology, which are characterized by self-organization. Many different physical work processes (work) in human cells are called cell work and can be grouped into five forms: synthetic, mechanical, electrical, concentration, and heat generation cell work. In addition to the flow of energy, these cell functions are based on fundamental processes of self-organization that we summarize with the term Entirety of molecular interaction (EoMI). This illustrates that cell work is caused by numerous molecular reactions, flow equilibrium, and mechanisms. Their number and interactions are so complex that they elude our perception in their entirety. To be able to describe cell functions in a biological/medical context, the parameters influencing cell work should be summarized in overarching influencing variables. These are “biological” energy, information, matter, and cell mechanics (EMIM). This makes it possible to describe and characterize the cell work involved in cell systems (e.g., respiratory chain, signal transmission, cell structure, or inheritance processes) and to demonstrate changes. If cell work and the different influencing parameters (EMIM influencing variables) are taken as the central property of the cell, specific gene mutations cannot be regarded as the sole cause for the initiation and progression of cancer. This reductionistic monocausal view does not do justice to the dynamic and highly complex system of a cell. Therefore, we postulate that each of the EMIM influencing variables described above is capable of changing the cell work and thus the order of a cell in such a way that it can develop into a cancer cell.
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