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Miyake Y, Hara Y, Umeda M, Banerjee I. Influenza A Virus: Cellular Entry. Subcell Biochem 2023; 106:387-401. [PMID: 38159235 DOI: 10.1007/978-3-031-40086-5_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
The frequent emergence of pathogenic viruses with pandemic potential has posed a significant threat to human health and economy, despite enormous advances in our understanding of infection mechanisms and devising countermeasures through developing various prophylactic and therapeutic strategies. The recent coronavirus disease (COVID-19) pandemic has re-emphasised the importance of rigorous research on virus infection mechanisms and highlighted the need for our preparedness for potential pandemics. Although viruses cannot self-replicate, they tap into host cell factors and processes for their entry, propagation and dissemination. Upon entering the host cells, viruses ingeniously utilise the innate biological functions of the host cell to replicate themselves and maintain their existence in the hosts. Influenza A virus (IAV), which has a negative-sense, single-stranded RNA as its genome, is no exception. IAVs are enveloped viruses with a lipid bilayer derived from the host cell membrane and have a surface covered with the spike glycoprotein haemagglutinin (HA) and neuraminidase (NA). Viral genome is surrounded by an M1 shell, forming a "capsid" in the virus particle. IAV particles use HA to recognise sialic acids on the cell surface of lung epithelial cells for their attachment. After attachment to the cell surface, IAV particles are endocytosed and sorted into the early endosomes. Subsequently, as the early endosomes mature into late endosomes, the endosomal lumen becomes acidified, and the low pH of the late endosomes induces conformational reaggangements in the HA to initiate fusion between the endosomal and viral membranes. Upon fusion, the viral capsid disintegrates and the viral ribonucleoprotein (vRNP) complexes containing the viral genome are released into the cytosol. The process of viral capsid disintegration is called "uncoating". After successful uncoating, the vRNPs are imported into the nucleus by importin α/β (IMP α/β), where viral replication and transcription take place and the new vRNPs are assembled. Recently, we have biochemically elucidated the molecular mechanisms of the processes of viral capsid uncoating subsequent viral genome dissociation. In this chapter, we present the molecular details of the viral uncoating process.
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Affiliation(s)
- Yasuyuki Miyake
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
- Institute for Advanced Research (IAR), Nagoya University, Nagoya, Japan.
| | - Yuya Hara
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Miki Umeda
- Department of Virology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Indranil Banerjee
- Department of Biological Sciences, Indian Institute of Science Education and Research, Mohali (IISER Mohali), Mohali, India.
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102
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Brownsword MJ, Locker N. A little less aggregation a little more replication: Viral manipulation of stress granules. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1741. [PMID: 35709333 PMCID: PMC10078398 DOI: 10.1002/wrna.1741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 04/29/2022] [Accepted: 05/05/2022] [Indexed: 01/31/2023]
Abstract
Recent exciting studies have uncovered how membrane-less organelles, also known as biocondensates, are providing cells with rapid response pathways, allowing them to re-organize their cellular contents and adapt to stressful conditions. Their assembly is driven by the phase separation of their RNAs and intrinsically disordered protein components into condensed foci. Among these, stress granules (SGs) are dynamic cytoplasmic biocondensates that form in response to many stresses, including activation of the integrated stress response or viral infections. SGs sit at the crossroads between antiviral signaling and translation because they concentrate signaling proteins and components of the innate immune response, in addition to translation machinery and stalled mRNAs. Consequently, they have been proposed to contribute to antiviral activities, and therefore are targeted by viral countermeasures. Equally, SGs components can be commandeered by viruses for their own efficient replication. Phase separation processes are an important component of the viral life cycle, for example, driving the assembly of replication factories or inclusion bodies. Therefore, in this review, we will outline the recent understanding of this complex interplay and tug of war between viruses, SGs, and their components. This article is categorized under: RNA in Disease and Development > RNA in Disease Translation > Regulation RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes.
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Affiliation(s)
- Matthew J. Brownsword
- Faculty of Health and Medical Sciences, School of Biosciences and MedicineUniversity of SurreyGuildfordSurreyUK
| | - Nicolas Locker
- Faculty of Health and Medical Sciences, School of Biosciences and MedicineUniversity of SurreyGuildfordSurreyUK
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103
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Huai Y, Mao W, Wang X, Lin X, Li Y, Chen Z, Qian A. How do RNA binding proteins trigger liquid-liquid phase separation in human health and diseases? Biosci Trends 2022; 16:389-404. [PMID: 36464283 DOI: 10.5582/bst.2022.01449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
RNA-binding proteins (RBPs) lie at the center of post-transcriptional regulation and protein synthesis, adding complexity to RNA life cycle. RBPs also participate in the formation of membrane-less organelles (MLOs) via undergoing liquid-liquid phase separation (LLPS), which underlies the formation of MLOs in eukaryotic cells. RBPs-triggered LLPS mainly relies on the interaction between their RNA recognition motifs (RRMs) and capped mRNA transcripts and the heterotypic multivalent interactions between their intrinsically disordered regions (IDRs) or prion-like domains (PLDs). In turn, the aggregations of RBPs are also dependent on the process of LLPS. RBPs-driven LLPS is involved in many intracellular processes (regulation of translation, mRNA storage and stabilization and cell signaling) and serves as the heart of cellular physiology and pathology. Thus, it is essential to comprehend the potential roles and investigate the internal mechanism of RPBs-triggered LLPS. In this review, we primarily expound on our current understanding of RBPs and they-triggered LLPS and summarize their physiological and pathological functions. Furthermore, we also summarize the potential roles of RBPs-triggered LLPS as novel therapeutic mechanism for human diseases. This review will help understand the mechanisms underlying LLPS and downstream regulation of RBPs and provide insights into the pathogenesis and therapy of complex diseases.
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Affiliation(s)
- Ying Huai
- Lab for Bone Metabolism, Xi'an Key Laboratory of Special Medicine and Health Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Key Lab for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Research Center for Special Medicine and Health Systems Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,NPU-UAB Joint Laboratory for Bone Metabolism, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China
| | - Wenjing Mao
- Lab for Bone Metabolism, Xi'an Key Laboratory of Special Medicine and Health Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Key Lab for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Research Center for Special Medicine and Health Systems Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,NPU-UAB Joint Laboratory for Bone Metabolism, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China
| | - Xuehao Wang
- Lab for Bone Metabolism, Xi'an Key Laboratory of Special Medicine and Health Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Key Lab for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Research Center for Special Medicine and Health Systems Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,NPU-UAB Joint Laboratory for Bone Metabolism, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China
| | - Xiao Lin
- Lab for Bone Metabolism, Xi'an Key Laboratory of Special Medicine and Health Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Key Lab for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Research Center for Special Medicine and Health Systems Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,NPU-UAB Joint Laboratory for Bone Metabolism, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China
| | - Yu Li
- Lab for Bone Metabolism, Xi'an Key Laboratory of Special Medicine and Health Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Key Lab for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Research Center for Special Medicine and Health Systems Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,NPU-UAB Joint Laboratory for Bone Metabolism, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China
| | - Zhihao Chen
- Lab for Bone Metabolism, Xi'an Key Laboratory of Special Medicine and Health Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Key Lab for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Research Center for Special Medicine and Health Systems Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,NPU-UAB Joint Laboratory for Bone Metabolism, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Department of Obstetrics and Gynecology, Xijing Hospital, The Fourth Military Medical University, Xi'an, China
| | - Airong Qian
- Lab for Bone Metabolism, Xi'an Key Laboratory of Special Medicine and Health Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Key Lab for Space Biosciences and Biotechnology, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,Research Center for Special Medicine and Health Systems Engineering, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China.,NPU-UAB Joint Laboratory for Bone Metabolism, School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, China
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104
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Chechetkin VR, Lobzin VV. Evolving ribonucleocapsid assembly/packaging signals in the genomes of the human and animal coronaviruses: targeting, transmission and evolution. J Biomol Struct Dyn 2022; 40:11239-11263. [PMID: 34338591 DOI: 10.1080/07391102.2021.1958061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
A world-wide COVID-19 pandemic intensified strongly the studies of molecular mechanisms related to the coronaviruses. The origin of coronaviruses and the risks of human-to-human, animal-to-human and human-to-animal transmission of coronaviral infections can be understood only on a broader evolutionary level by detailed comparative studies. In this paper, we studied ribonucleocapsid assembly-packaging signals (RNAPS) in the genomes of all seven known pathogenic human coronaviruses, SARS-CoV, SARS-CoV-2, MERS-CoV, HCoV-OC43, HCoV-HKU1, HCoV-229E and HCoV-NL63 and compared them with RNAPS in the genomes of the related animal coronaviruses including SARS-Bat-CoV, MERS-Camel-CoV, MHV, Bat-CoV MOP1, TGEV and one of camel alphacoronaviruses. RNAPS in the genomes of coronaviruses were evolved due to weakly specific interactions between genomic RNA and N proteins in helical nucleocapsids. Combining transitional genome mapping and Jaccard correlation coefficients allows us to perform the analysis directly in terms of underlying motifs distributed over the genome. In all coronaviruses, RNAPS were distributed quasi-periodically over the genome with the period about 54 nt biased to 57 nt and to 51 nt for the genomes longer and shorter than that of SARS-CoV, respectively. The comparison with the experimentally verified packaging signals for MERS-CoV, MHV and TGEV proved that the distribution of particular motifs is strongly correlated with the packaging signals. We also found that many motifs were highly conserved in both characters and positioning on the genomes throughout the lineages that make them promising therapeutic targets. The mechanisms of encapsidation can affect the recombination and co-infection as well.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Vladimir R Chechetkin
- Engelhardt Institute of Molecular Biology of Russian Academy of Sciences, Moscow, Russia
| | - Vasily V Lobzin
- School of Physics, University of Sydney, Sydney, NSW, Australia
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105
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Morse M, Sefcikova J, Rouzina I, Beuning PJ, Williams M. Structural domains of SARS-CoV-2 nucleocapsid protein coordinate to compact long nucleic acid substrates. Nucleic Acids Res 2022; 51:290-303. [PMID: 36533523 PMCID: PMC9841419 DOI: 10.1093/nar/gkac1179] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/28/2022] [Accepted: 11/25/2022] [Indexed: 12/23/2022] Open
Abstract
The SARS-CoV-2 nucleocapsid (N) protein performs several functions including binding, compacting, and packaging the ∼30 kb viral genome into the viral particle. N protein consists of two ordered domains, with the N terminal domain (NTD) primarily associated with RNA binding and the C terminal domain (CTD) primarily associated with dimerization/oligomerization, and three intrinsically disordered regions, an N-arm, a C-tail, and a linker that connects the NTD and CTD. We utilize an optical tweezers system to isolate a long single-stranded nucleic acid substrate to measure directly the binding and packaging function of N protein at a single molecule level in real time. We find that N protein binds the nucleic acid substrate with high affinity before oligomerizing and forming a highly compact structure. By comparing the activities of truncated protein variants missing the NTD, CTD, and/or linker, we attribute specific steps in this process to the structural domains of N protein, with the NTD driving initial binding to the substrate and ensuring high localized protein density that triggers interprotein interactions mediated by the CTD, which forms a compact and stable protein-nucleic acid complex suitable for packaging into the virion.
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Affiliation(s)
- Michael Morse
- Department of Physics, Northeastern University, Boston, MA, USA
| | - Jana Sefcikova
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, USA
| | - Ioulia Rouzina
- Department of Chemistry and Biochemistry, Ohio State University, Columbus, OH, USA
| | - Penny J Beuning
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, USA
| | - Mark C Williams
- To whom correspondence should be addressed. Tel: +1 617 373 5705;
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106
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Shapira T, Vimalanathan S, Rens C, Pichler V, Peña-Díaz S, Jordana G, Rees W, Winkler DFH, Sarai I, Steiner T, Jean F, Pelech S, Av-Gay Y. Inhibition of glycogen synthase kinase-3-beta (GSK3β) blocks nucleocapsid phosphorylation and SARS-CoV-2 replication. MOLECULAR BIOMEDICINE 2022; 3:43. [PMID: 36508083 PMCID: PMC9742639 DOI: 10.1186/s43556-022-00111-1] [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: 09/23/2022] [Accepted: 11/19/2022] [Indexed: 12/14/2022] Open
Abstract
GSK3β has been proposed to have an essential role in Coronaviridae infections. Screening of a targeted library of GSK3β inhibitors against both SARS-CoV-2 and HCoV-229E to identify broad-spectrum anti-Coronaviridae inhibitors resulted in the identification of a high proportion of active compounds with low toxicity to host cells. A selected lead compound, T-1686568, showed low micromolar, dose-dependent activity against SARS-CoV-2 and HCoV-229E. T-1686568 showed efficacy in viral-infected cultured cells and primary 2D organoids. T-1686568 also inhibited SARS-CoV-2 variants of concern Delta and Omicron. Importantly, while inhibition by T-1686568 resulted in the overall reduction of viral load and protein translation, GSK3β inhibition resulted in cellular accumulation of the nucleocapsid protein relative to the spike protein. Following identification of potential phosphorylation sites of Coronaviridae nucleocapsid, protein kinase substrate profiling assays combined with Western blotting analysis of nine host kinases showed that the SARS-CoV-2 nucleocapsid could be phosphorylated by GSK3β and PKCa. GSK3β phosphorylated SARS-CoV-2 nucleocapsid on the S180/S184, S190/S194 and T198 phospho-sites, following previous priming in the adjacent S188, T198 and S206, respectively. Such inhibition presents a compelling target for broad-spectrum anti-Coronaviridae compound development, and underlies the mechanism of action of GSK3β host-directed therapy against this class of obligate intracellular pathogens.
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Affiliation(s)
- Tirosh Shapira
- grid.17091.3e0000 0001 2288 9830Division of Infectious Disease, Department of Medicine, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada ,grid.17091.3e0000 0001 2288 9830Department of Microbiology and Immunology, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada
| | - Selvarani Vimalanathan
- grid.17091.3e0000 0001 2288 9830Division of Infectious Disease, Department of Medicine, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada
| | - Celine Rens
- grid.17091.3e0000 0001 2288 9830Division of Infectious Disease, Department of Medicine, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada
| | - Virginia Pichler
- grid.17091.3e0000 0001 2288 9830Department of Microbiology and Immunology, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada
| | - Sandra Peña-Díaz
- grid.17091.3e0000 0001 2288 9830Department of Microbiology and Immunology, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada
| | - Grace Jordana
- grid.17091.3e0000 0001 2288 9830Department of Microbiology and Immunology, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada
| | - William Rees
- grid.17091.3e0000 0001 2288 9830Division of Infectious Disease, Department of Medicine, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada
| | - Dirk F. H. Winkler
- grid.292479.3Kinexus Bioinformatics Corporation, Suite 1 – 8755 Ash Street, Vancouver, BC V6P 6T3 Canada
| | - Iqbal Sarai
- grid.292479.3Kinexus Bioinformatics Corporation, Suite 1 – 8755 Ash Street, Vancouver, BC V6P 6T3 Canada
| | - Theodore Steiner
- grid.17091.3e0000 0001 2288 9830Division of Infectious Disease, Department of Medicine, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada
| | - François Jean
- grid.17091.3e0000 0001 2288 9830Department of Microbiology and Immunology, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada
| | - Steven Pelech
- grid.17091.3e0000 0001 2288 9830Division of Infectious Disease, Department of Medicine, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada ,grid.292479.3Kinexus Bioinformatics Corporation, Suite 1 – 8755 Ash Street, Vancouver, BC V6P 6T3 Canada
| | - Yossef Av-Gay
- grid.17091.3e0000 0001 2288 9830Division of Infectious Disease, Department of Medicine, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada ,grid.17091.3e0000 0001 2288 9830Department of Microbiology and Immunology, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada
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107
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Nucleoside Analogs and Perylene Derivatives Modulate Phase Separation of SARS-CoV-2 N Protein and Genomic RNA In Vitro. Int J Mol Sci 2022; 23:ijms232315281. [PMID: 36499608 PMCID: PMC9738865 DOI: 10.3390/ijms232315281] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 12/12/2022] Open
Abstract
The life cycle of severe acute respiratory syndrome coronavirus 2 includes several steps that are supposedly mediated by liquid-liquid phase separation (LLPS) of the viral nucleocapsid protein (N) and genomic RNA. To facilitate the rational design of LLPS-targeting therapeutics, we modeled N-RNA biomolecular condensates in vitro and analyzed their sensitivity to several small-molecule antivirals. The model condensates were obtained and visualized under physiological conditions using an optimized RNA sequence enriched with N-binding motifs. The antivirals were selected based on their presumed ability to compete with RNA for specific N sites or interfere with non-specific pi-pi/cation-pi interactions. The set of antivirals included fleximers, 5'-norcarbocyclic nucleoside analogs, and perylene-harboring nucleoside analogs as well as non-nucleoside amphiphilic and hydrophobic perylene derivatives. Most of these antivirals enhanced the formation of N-RNA condensates. Hydrophobic perylene derivatives and 5'-norcarbocyclic derivatives caused up to 50-fold and 15-fold enhancement, respectively. Molecular modeling data argue that hydrophobic compounds do not hamper specific N-RNA interactions and may promote non-specific ones. These findings shed light on the determinants of potent small-molecule modulators of viral LLPS.
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108
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Li H, Ernst C, Kolonko-Adamska M, Greb-Markiewicz B, Man J, Parissi V, Ng BWL. Phase separation in viral infections. Trends Microbiol 2022; 30:1217-1231. [PMID: 35902318 DOI: 10.1016/j.tim.2022.06.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 06/24/2022] [Accepted: 06/27/2022] [Indexed: 01/13/2023]
Abstract
Viruses rely on the reprogramming of cellular processes to enable efficient viral replication; this often requires subcompartmentalization within the host cell. Liquid-liquid phase separation (LLPS) has emerged as a fundamental principle to organize and subdivide cellular processes, and plays an important role in viral life cycles. Despite substantial advances in the field, elucidating the exact organization and function of these organelles remains a major challenge. In this review, we summarize the biochemical basis of condensate formation, the role of LLPS during viral infection, and interplay of LLPS with innate immune responses. Finally, we discuss possible strategies and molecules to modulate LLPS during viral infections.
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Affiliation(s)
- Haohua Li
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong; Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Christina Ernst
- School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Marta Kolonko-Adamska
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry, Wroclaw University of Science and Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland
| | - Beata Greb-Markiewicz
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry, Wroclaw University of Science and Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland
| | - Jackie Man
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong; Faculty of Medicine, Imperial College, London, UK
| | - Vincent Parissi
- Microbiologie Fondamentale et Pathogénicité Laboratory (MPF), UMR 5234, « Mobility of pathogenic genomes and chromatin dynamics » team (MobilVIR), CNRS-University of Bordeaux, Bordeaux, France
| | - Billy Wai-Lung Ng
- School of Pharmacy, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong.
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109
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Focus on Marine Animal Safety and Marine Bioresources in Response to the SARS-CoV-2 Crisis. Int J Mol Sci 2022; 23:ijms232315136. [PMID: 36499463 PMCID: PMC9737530 DOI: 10.3390/ijms232315136] [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: 10/18/2022] [Revised: 11/18/2022] [Accepted: 11/29/2022] [Indexed: 12/04/2022] Open
Abstract
SARS-CoV-2 as a zoonotic virus has significantly affected daily life and social behavior since its outbreak in late 2019. The concerns over its transmission through different media directly or indirectly have evoked great attention about the survival of SARS-CoV-2 virions in the environment and its potential infection of other animals. To evaluate the risk of infection by SARS-CoV-2 and to counteract the COVID-19 disease, extensive studies have been performed to understand SARS-CoV-2 biogenesis and its pathogenesis. This review mainly focuses on the molecular architecture of SARS-CoV-2, its potential for infecting marine animals, and the prospect of drug discovery using marine natural products to combat SARS-CoV-2. The main purposes of this review are to piece together progress in SARS-CoV-2 functional genomic studies and antiviral drug development, and to raise our awareness of marine animal safety on exposure to SARS-CoV-2.
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110
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Zhang H, Li S, Zhang L, Mathews D, Huang L. LazySampling and LinearSampling: fast stochastic sampling of RNA secondary structure with applications to SARS-CoV-2. Nucleic Acids Res 2022; 51:e7. [PMID: 36401871 PMCID: PMC9881153 DOI: 10.1093/nar/gkac1029] [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: 05/27/2022] [Revised: 09/22/2022] [Accepted: 10/21/2022] [Indexed: 11/21/2022] Open
Abstract
Many RNAs fold into multiple structures at equilibrium, and there is a need to sample these structures according to their probabilities in the ensemble. The conventional sampling algorithm suffers from two limitations: (i) the sampling phase is slow due to many repeated calculations; and (ii) the end-to-end runtime scales cubically with the sequence length. These issues make it difficult to be applied to long RNAs, such as the full genomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To address these problems, we devise a new sampling algorithm, LazySampling, which eliminates redundant work via on-demand caching. Based on LazySampling, we further derive LinearSampling, an end-to-end linear time sampling algorithm. Benchmarking on nine diverse RNA families, the sampled structures from LinearSampling correlate better with the well-established secondary structures than Vienna RNAsubopt and RNAplfold. More importantly, LinearSampling is orders of magnitude faster than standard tools, being 428× faster (72 s versus 8.6 h) than RNAsubopt on the full genome of SARS-CoV-2 (29 903 nt). The resulting sample landscape correlates well with the experimentally guided secondary structure models, and is closer to the alternative conformations revealed by experimentally driven analysis. Finally, LinearSampling finds 23 regions of 15 nt with high accessibilities in the SARS-CoV-2 genome, which are potential targets for COVID-19 diagnostics and therapeutics.
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Affiliation(s)
- He Zhang
- Baidu Research, Sunnyvale, CA, USA,School of Electrical Engineering & Computer Science, Oregon State University, Corvallis, OR, USA
| | - Sizhen Li
- School of Electrical Engineering & Computer Science, Oregon State University, Corvallis, OR, USA
| | - Liang Zhang
- School of Electrical Engineering & Computer Science, Oregon State University, Corvallis, OR, USA
| | - David H Mathews
- Department of Biochemistry & Biophysics, University of Rochester Medical Center, Rochester, NY 14642, USA,Center for RNA Biology, University of Rochester Medical Center, Rochester, NY 14642, USA,Department of Biostatistics & Computational Biology, University of Rochester Medical Center, Rochester, NY 14642, USA
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111
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Rolband L, Beasock D, Wang Y, Shu YG, Dinman JD, Schlick T, Zhou Y, Kieft JS, Chen SJ, Bussi G, Oukhaled A, Gao X, Šulc P, Binzel D, Bhullar AS, Liang C, Guo P, Afonin KA. Biomotors, viral assembly, and RNA nanobiotechnology: Current achievements and future directions. Comput Struct Biotechnol J 2022; 20:6120-6137. [PMID: 36420155 PMCID: PMC9672130 DOI: 10.1016/j.csbj.2022.11.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/04/2022] [Accepted: 11/04/2022] [Indexed: 11/13/2022] Open
Abstract
The International Society of RNA Nanotechnology and Nanomedicine (ISRNN) serves to further the development of a wide variety of functional nucleic acids and other related nanotechnology platforms. To aid in the dissemination of the most recent advancements, a biennial discussion focused on biomotors, viral assembly, and RNA nanobiotechnology has been established where international experts in interdisciplinary fields such as structural biology, biophysical chemistry, nanotechnology, cell and cancer biology, and pharmacology share their latest accomplishments and future perspectives. The results summarized here highlight advancements in our understanding of viral biology and the structure-function relationship of frame-shifting elements in genomic viral RNA, improvements in the predictions of SHAPE analysis of 3D RNA structures, and the understanding of dynamic RNA structures through a variety of experimental and computational means. Additionally, recent advances in the drug delivery, vaccine design, nanopore technologies, biomotor and biomachine development, DNA packaging, RNA nanotechnology, and drug delivery are included in this critical review. We emphasize some of the novel accomplishments, major discussion topics, and present current challenges and perspectives of these emerging fields.
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Affiliation(s)
- Lewis Rolband
- University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Damian Beasock
- University of North Carolina at Charlotte, Charlotte, NC 28223, USA
| | - Yang Wang
- Wenzhou Institute, University of China Academy of Sciences, 1st, Jinlian Road, Longwan District, Wenzhou, Zhjiang 325001, China
| | - Yao-Gen Shu
- Wenzhou Institute, University of China Academy of Sciences, 1st, Jinlian Road, Longwan District, Wenzhou, Zhjiang 325001, China
| | | | - Tamar Schlick
- New York University, Department of Chemistry and Courant Institute of Mathematical Sciences, Simons Center for Computational Physical Chemistry, New York, NY 10012, USA
| | - Yaoqi Zhou
- Institute for Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen, Guangdong 518107, China
| | - Jeffrey S. Kieft
- University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Shi-Jie Chen
- University of Missouri at Columbia, Columbia, MO 65211, USA
| | - Giovanni Bussi
- Scuola Internazionale Superiore di Studi Avanzati, via Bonomea 265, 34136 Trieste, Italy
| | | | - Xingfa Gao
- National Center for Nanoscience and Technology of China, Beijing 100190, China
| | - Petr Šulc
- Arizona State University, Tempe, AZ, USA
| | | | | | - Chenxi Liang
- The Ohio State University, Columbus, OH 43210, USA
| | - Peixuan Guo
- The Ohio State University, Columbus, OH 43210, USA
| | - Kirill A. Afonin
- University of North Carolina at Charlotte, Charlotte, NC 28223, USA
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112
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Mitrea DM, Mittasch M, Gomes BF, Klein IA, Murcko MA. Modulating biomolecular condensates: a novel approach to drug discovery. Nat Rev Drug Discov 2022; 21:841-862. [PMID: 35974095 PMCID: PMC9380678 DOI: 10.1038/s41573-022-00505-4] [Citation(s) in RCA: 96] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/08/2022] [Indexed: 12/12/2022]
Abstract
In the past decade, membraneless assemblies known as biomolecular condensates have been reported to play key roles in many cellular functions by compartmentalizing specific proteins and nucleic acids in subcellular environments with distinct properties. Furthermore, growing evidence supports the view that biomolecular condensates often form by phase separation, in which a single-phase system demixes into a two-phase system consisting of a condensed phase and a dilute phase of particular biomolecules. Emerging understanding of condensate function in normal and aberrant cellular states, and of the mechanisms of condensate formation, is providing new insights into human disease and revealing novel therapeutic opportunities. In this Perspective, we propose that such insights could enable a previously unexplored drug discovery approach based on identifying condensate-modifying therapeutics (c-mods), and we discuss the strategies, techniques and challenges involved.
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113
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Carlson CR, Adly AN, Bi M, Howard CJ, Frost A, Cheng Y, Morgan DO. Reconstitution of the SARS-CoV-2 ribonucleosome provides insights into genomic RNA packaging and regulation by phosphorylation. J Biol Chem 2022; 298:102560. [PMID: 36202211 PMCID: PMC9529352 DOI: 10.1016/j.jbc.2022.102560] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/17/2022] [Accepted: 09/19/2022] [Indexed: 11/06/2022] Open
Abstract
The nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 is responsible for compaction of the ∼30-kb RNA genome in the ∼90-nm virion. Previous studies suggest that each virion contains 35 to 40 viral ribonucleoprotein (vRNP) complexes, or ribonucleosomes, arrayed along the genome. There is, however, little mechanistic understanding of the vRNP complex. Here, we show that N protein, when combined in vitro with short fragments of the viral genome, forms 15-nm particles similar to the vRNP structures observed within virions. These vRNPs depend on regions of N protein that promote protein-RNA and protein-protein interactions. Phosphorylation of N protein in its disordered serine/arginine region weakens these interactions to generate less compact vRNPs. We propose that unmodified N protein binds structurally diverse regions in genomic RNA to form compact vRNPs within the nucleocapsid, while phosphorylation alters vRNP structure to support other N protein functions in viral transcription.
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Affiliation(s)
| | - Armin N Adly
- Department of Physiology, University of California, San Francisco, California, USA
| | - Maxine Bi
- Department of Biochemistry & Biophysics, University of California, San Francisco, California, USA
| | - Conor J Howard
- Department of Biochemistry & Biophysics, University of California, San Francisco, California, USA
| | - Adam Frost
- Department of Biochemistry & Biophysics, University of California, San Francisco, California, USA
| | - Yifan Cheng
- Department of Biochemistry & Biophysics, University of California, San Francisco, California, USA
| | - David O Morgan
- Department of Physiology, University of California, San Francisco, California, USA.
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114
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Rapid Reversible Osmoregulation of Cytoplasmic Biomolecular Condensates of Human Interferon-α-Induced Antiviral MxA GTPase. Int J Mol Sci 2022; 23:ijms232112739. [PMID: 36361529 PMCID: PMC9655878 DOI: 10.3390/ijms232112739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/18/2022] [Accepted: 10/20/2022] [Indexed: 01/24/2023] Open
Abstract
We previously discovered that exogenously expressed GFP-tagged cytoplasmic human myxovirus resistance protein (MxA), a major antiviral effector of Type I and III interferons (IFNs) against several RNA- and DNA-containing viruses, existed in the cytoplasm in phase-separated membraneless biomolecular condensates of varying sizes and shapes with osmotically regulated disassembly and reassembly. In this study we investigated whether cytoplasmic IFN-α-induced endogenous human MxA structures were also biomolecular condensates, displayed hypotonic osmoregulation and the mechanisms involved. Both IFN-α-induced endogenous MxA and exogenously expressed GFP-MxA formed cytoplasmic condensates in A549 lung and Huh7 hepatoma cells which rapidly disassembled within 1-2 min when cells were exposed to 1,6-hexanediol or to hypotonic buffer (~40-50 mOsm). Both reassembled into new structures within 1-2 min of shifting cells to isotonic culture medium (~330 mOsm). Strikingly, MxA condensates in cells continuously exposed to culture medium of moderate hypotonicity (in the range one-fourth, one-third or one-half isotonicity; range 90-175 mOsm) first rapidly disassembled within 1-3 min, and then, in most cells, spontaneously reassembled 7-15 min later into new structures. This spontaneous reassembly was inhibited by 2-deoxyglucose (thus, was ATP-dependent) and by dynasore (thus, required membrane internalization). Indeed, condensate reassembly was preceded by crowding of the cytosolic space by large vacuole-like dilations (VLDs) derived from internalized plasma membrane. Remarkably, the antiviral activity of GFP-MxA against vesicular stomatitis virus survived hypoosmolar disassembly and subsequent reassembly. The data highlight the exquisite osmosensitivity of MxA condensates, and the preservation of antiviral activity in the face of hypotonic stress.
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115
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Amahong K, Zhang W, Zhou Y, Zhang S, Yin J, Li F, Xu H, Yan T, Yue Z, Liu Y, Hou T, Qiu Y, Tao L, Han L, Zhu F. CovInter: interaction data between coronavirus RNAs and host proteins. Nucleic Acids Res 2022; 51:D546-D556. [PMID: 36200814 PMCID: PMC9825556 DOI: 10.1093/nar/gkac834] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/07/2022] [Accepted: 09/16/2022] [Indexed: 01/29/2023] Open
Abstract
Coronavirus has brought about three massive outbreaks in the past two decades. Each step of its life cycle invariably depends on the interactions among virus and host molecules. The interaction between virus RNA and host protein (IVRHP) is unique compared to other virus-host molecular interactions and represents not only an attempt by viruses to promote their translation/replication, but also the host's endeavor to combat viral pathogenicity. In other words, there is an urgent need to develop a database for providing such IVRHP data. In this study, a new database was therefore constructed to describe the interactions between coronavirus RNAs and host proteins (CovInter). This database is unique in (a) unambiguously characterizing the interactions between virus RNA and host protein, (b) comprehensively providing experimentally validated biological function for hundreds of host proteins key in viral infection and (c) systematically quantifying the differential expression patterns (before and after infection) of these key proteins. Given the devastating and persistent threat of coronaviruses, CovInter is highly expected to fill the gap in the whole process of the 'molecular arms race' between viruses and their hosts, which will then aid in the discovery of new antiviral therapies. It's now free and publicly accessible at: https://idrblab.org/covinter/.
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Affiliation(s)
| | | | | | - Song Zhang
- College of Pharmaceutical Sciences, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou 310058, China
| | - Jiayi Yin
- College of Pharmaceutical Sciences, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou 310058, China,Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, Alibaba-Zhejiang University Joint Research Center of Future Digital Healthcare, Hangzhou 330110, China
| | - Fengcheng Li
- College of Pharmaceutical Sciences, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou 310058, China,Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, Alibaba-Zhejiang University Joint Research Center of Future Digital Healthcare, Hangzhou 330110, China
| | - Hongquan Xu
- Key Laboratory of Elemene Class Anti-cancer Chinese Medicines, School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China
| | - Tianci Yan
- Key Laboratory of Elemene Class Anti-cancer Chinese Medicines, School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China
| | - Zixuan Yue
- Key Laboratory of Elemene Class Anti-cancer Chinese Medicines, School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China
| | - Yuhong Liu
- Key Laboratory of Elemene Class Anti-cancer Chinese Medicines, School of Pharmacy, Hangzhou Normal University, Hangzhou 311121, China
| | - Tingjun Hou
- College of Pharmaceutical Sciences, The Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou 310058, China
| | - Yunqing Qiu
- State Key Laboratory for Diagnosis and Treatment of Infectious Disease, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang Provincial Key Laboratory for Drug Clinical Research and Evaluation, The First Affiliated Hospital, Zhejiang University, Hangzhou 310000, China
| | - Lin Tao
- Correspondence may also be addressed to Lin Tao.
| | - Lianyi Han
- Correspondence may also be addressed to Lianyi Han.
| | - Feng Zhu
- To whom correspondence should be addressed. Tel: +86 189 8946 6518; Fax: +86 571 8820 8444;
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116
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Wu C, Holehouse AS, Leung DW, Amarasinghe GK, Dutch RE. Liquid Phase Partitioning in Virus Replication: Observations and Opportunities. Annu Rev Virol 2022; 9:285-306. [PMID: 35709511 PMCID: PMC11331907 DOI: 10.1146/annurev-virology-093020-013659] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Viruses frequently carry out replication in specialized compartments within cells. The effect of these structures on virus replication is poorly understood. Recent research supports phase separation as a foundational principle for organization of cellular components with the potential to influence viral replication. In this review, phase separation is described in the context of formation of viral replication centers, with an emphasis on the nonsegmented negative-strand RNA viruses. Consideration is given to the interplay between phase separation and the critical processes of viral transcription and genome replication, and the role of these regions in pathogen-host interactions is discussed. Finally, critical questions that must be addressed to fully understand how phase separation influences viral replication and the viral life cycle are presented, along with information about new approaches that could be used to make important breakthroughs in this emerging field.
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Affiliation(s)
- Chao Wu
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri, USA
- Center for Science and Engineering Living Systems, Washington University, St. Louis, Missouri, USA
| | - Daisy W Leung
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Rebecca Ellis Dutch
- Department of Molecular and Cellular Biochemistry, University of Kentucky, College of Medicine, Lexington, Kentucky, USA;
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117
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Vazquez DS, Toledo PL, Gianotti AR, Ermácora MR. Protein conformation and biomolecular condensates. Curr Res Struct Biol 2022; 4:285-307. [PMID: 36164646 PMCID: PMC9508354 DOI: 10.1016/j.crstbi.2022.09.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 09/08/2022] [Accepted: 09/13/2022] [Indexed: 10/27/2022] Open
Abstract
Protein conformation and cell compartmentalization are fundamental concepts and subjects of vast scientific endeavors. In the last two decades, we have witnessed exciting advances that unveiled the conjunction of these concepts. An avalanche of studies highlighted the central role of biomolecular condensates in membraneless subcellular compartmentalization that permits the spatiotemporal organization and regulation of myriads of simultaneous biochemical reactions and macromolecular interactions. These studies have also shown that biomolecular condensation, driven by multivalent intermolecular interactions, is mediated by order-disorder transitions of protein conformation and by protein domain architecture. Conceptually, protein condensation is a distinct level in protein conformational landscape in which collective folding of large collections of molecules takes place. Biomolecular condensates arise by the physical process of phase separation and comprise a variety of bodies ranging from membraneless organelles to liquid condensates to solid-like conglomerates, spanning lengths from mesoscopic clusters (nanometers) to micrometer-sized objects. In this review, we summarize and discuss recent work on the assembly, composition, conformation, material properties, thermodynamics, regulation, and functions of these bodies. We also review the conceptual framework for future studies on the conformational dynamics of condensed proteins in the regulation of cellular processes.
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Affiliation(s)
- Diego S. Vazquez
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes and Grupo de Biología Estructural y Biotecnología, IMBICE, CONICET, Universidad Nacional de Quilmes, Argentina
| | - Pamela L. Toledo
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes and Grupo de Biología Estructural y Biotecnología, IMBICE, CONICET, Universidad Nacional de Quilmes, Argentina
| | - Alejo R. Gianotti
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes and Grupo de Biología Estructural y Biotecnología, IMBICE, CONICET, Universidad Nacional de Quilmes, Argentina
| | - Mario R. Ermácora
- Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes and Grupo de Biología Estructural y Biotecnología, IMBICE, CONICET, Universidad Nacional de Quilmes, Argentina
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118
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Huang N, Dong H, Shao B. Phase separation in immune regulation and immune-related diseases. J Mol Med (Berl) 2022; 100:1427-1440. [PMID: 36085373 PMCID: PMC9462646 DOI: 10.1007/s00109-022-02253-9] [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: 06/13/2022] [Revised: 08/26/2022] [Accepted: 08/31/2022] [Indexed: 11/28/2022]
Abstract
Phase separation is an emerging paradigm for understanding the biochemical interactions between proteins, DNA, and RNA. Research over the past decade has provided mounting evidence that phase separation modulates a great variety of cellular activities. Particularly, phase separation is directly relevant to immune signaling, immune cells, and immune-related diseases like cancer, neurodegenerative diseases, and even SARS-CoV-2. In this review, we summarized current knowledge of phase separation in immunology and emerging findings related to immune responses as they enable possible treatment approaches.
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Affiliation(s)
- Ning Huang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases and State Key Laboratory of Biotherapy, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China
| | - Hao Dong
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases and State Key Laboratory of Biotherapy, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China
| | - Bin Shao
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases and State Key Laboratory of Biotherapy, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.
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119
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Fan S, Sun W, Fan L, Wu N, Sun W, Ma H, Chen S, Li Z, Li Y, Zhang J, Yan J. The highly conserved RNA-binding specificity of nucleocapsid protein facilitates the identification of drugs with broad anti-coronavirus activity. Comput Struct Biotechnol J 2022; 20:5040-5044. [PMID: 36097552 PMCID: PMC9454191 DOI: 10.1016/j.csbj.2022.09.007] [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: 08/03/2022] [Revised: 09/05/2022] [Accepted: 09/05/2022] [Indexed: 11/06/2022] Open
Abstract
The binding of SARS-CoV-2 nucleocapsid (N) protein to both the 5'- and 3'-ends of genomic RNA has different implications arising from its binding to the central region during virion assembly. However, the mechanism underlying selective binding remains unknown. Herein, we performed the high-throughput RNA-SELEX (HTR-SELEX) to determine the RNA-binding specificity of the N proteins of various SARS-CoV-2 variants as well as other β-coronaviruses and showed that N proteins could bind two unrelated sequences, both of which were highly conserved across all variants and species. Interestingly, both sequences are virtually absent from the human transcriptome; however, they exhibit a highly enriched, mutually complementary distribution in the coronavirus genome, highlighting their varied functions in genome packaging. Our results provide mechanistic insights into viral genome packaging, thereby increasing the feasibility of developing drugs with broad-spectrum anti-coronavirus activity by targeting RNA binding by N proteins.
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Affiliation(s)
- Shaorong Fan
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education and Provincial Key Laboratory of Biotechnology, School of Medicine, Northwest University, Xi’an, China
- Department of Biomedical Sciences, The Tung Biomedical Sciences Centre, City University of Hong Kong, Kowloon Tong, Hong Kong Special Administrative Region
| | - Wenju Sun
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education and Provincial Key Laboratory of Biotechnology, School of Medicine, Northwest University, Xi’an, China
| | - Ligang Fan
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education and Provincial Key Laboratory of Biotechnology, School of Medicine, Northwest University, Xi’an, China
- Department of Biomedical Sciences, The Tung Biomedical Sciences Centre, City University of Hong Kong, Kowloon Tong, Hong Kong Special Administrative Region
- Department of Precision Diagnostic and Therapeutic Technology, The City University of Hong Kong Shenzhen Futian Research Institute, Shenzhen, China
| | - Nan Wu
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education and Provincial Key Laboratory of Biotechnology, School of Medicine, Northwest University, Xi’an, China
- Department of Biomedical Sciences, The Tung Biomedical Sciences Centre, City University of Hong Kong, Kowloon Tong, Hong Kong Special Administrative Region
| | - Wei Sun
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education and Provincial Key Laboratory of Biotechnology, School of Medicine, Northwest University, Xi’an, China
| | - Haiqian Ma
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education and Provincial Key Laboratory of Biotechnology, School of Medicine, Northwest University, Xi’an, China
| | - Siyuan Chen
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, Sha Tin, Hong Kong Special Administrative Region
| | - Zitong Li
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, Sha Tin, Hong Kong Special Administrative Region
| | - Yu Li
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, Sha Tin, Hong Kong Special Administrative Region
| | - Jilin Zhang
- Department of Biomedical Sciences, The Tung Biomedical Sciences Centre, City University of Hong Kong, Kowloon Tong, Hong Kong Special Administrative Region
| | - Jian Yan
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education and Provincial Key Laboratory of Biotechnology, School of Medicine, Northwest University, Xi’an, China
- Department of Biomedical Sciences, The Tung Biomedical Sciences Centre, City University of Hong Kong, Kowloon Tong, Hong Kong Special Administrative Region
- Department of Precision Diagnostic and Therapeutic Technology, The City University of Hong Kong Shenzhen Futian Research Institute, Shenzhen, China
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120
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Stewart PDS, Bach JL. The natural thermal sensitivity of SARS-CoV-2. INFECTIOUS MEDICINE 2022; 1:227-228. [PMID: 38014365 PMCID: PMC9419432 DOI: 10.1016/j.imj.2022.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 08/23/2022] [Indexed: 11/22/2022]
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121
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Zachrdla M, Savastano A, Ibáñez de Opakua A, Cima‐Omori M, Zweckstetter M. Contributions of the N-terminal intrinsically disordered region of the severe acute respiratory syndrome coronavirus 2 nucleocapsid protein to RNA-induced phase separation. Protein Sci 2022; 31:e4409. [PMID: 36040256 PMCID: PMC9387207 DOI: 10.1002/pro.4409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 07/23/2022] [Accepted: 07/25/2022] [Indexed: 11/23/2022]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid protein is an essential structural component of mature virions, encapsulating the genomic RNA and modulating RNA transcription and replication. Several of its activities might be associated with the protein's ability to undergo liquid-liquid phase separation. NSARS-CoV-2 contains an intrinsically disordered region at its N-terminus (NTE) that can be phosphorylated and is affected by mutations found in human COVID-19 infections, including in the Omicron variant of concern. Here, we show that NTE deletion decreases the range of RNA concentrations that can induce phase separation of NSARS-CoV-2 . In addition, deletion of the prion-like NTE allows NSARS-CoV-2 droplets to retain their liquid-like nature during incubation. We further demonstrate that RNA-binding engages multiple parts of the NTE and changes NTE's structural properties. The results form the foundation to characterize the impact of N-terminal mutations and post-translational modifications on the molecular properties of the SARS-CoV-2 nucleocapsid protein. STATEMENT: The nucleocapsid protein of SARS-CoV-2 plays an important role in both genome packaging and viral replication upon host infection. Replication has been associated with RNA-induced liquid-liquid phase separation of the nucleocapsid protein. We present insights into the role of the N-terminal part of the nucleocapsid protein in the protein's RNA-mediated liquid-liquid phase separation.
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Affiliation(s)
- Milan Zachrdla
- Research group Translational Structural BiologyGerman Center for Neurodegenerative Diseases (DZNE)GöttingenGermany
| | - Adriana Savastano
- Research group Translational Structural BiologyGerman Center for Neurodegenerative Diseases (DZNE)GöttingenGermany
| | - Alain Ibáñez de Opakua
- Research group Translational Structural BiologyGerman Center for Neurodegenerative Diseases (DZNE)GöttingenGermany
| | - Maria‐Sol Cima‐Omori
- Research group Translational Structural BiologyGerman Center for Neurodegenerative Diseases (DZNE)GöttingenGermany
| | - Markus Zweckstetter
- Research group Translational Structural BiologyGerman Center for Neurodegenerative Diseases (DZNE)GöttingenGermany
- NMR‐based Structural BiologyMax Planck Institute for Multidisciplinary SciencesGöttingenGermany
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122
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Nishitsuji H, Iwahori S, Ohmori M, Shimotohno K, Murata T. Ubiquitination of SARS-CoV-2 NSP6 and ORF7a Facilitates NF-κB Activation. mBio 2022; 13:e0097122. [PMID: 35856559 PMCID: PMC9426613 DOI: 10.1128/mbio.00971-22] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 07/01/2022] [Indexed: 11/20/2022] Open
Abstract
Patients with severe coronavirus disease 2019 tend to have high levels of proinflammatory cytokines, which eventually lead to cytokine storm and the development of acute respiratory distress syndrome. However, the detailed molecular mechanisms of proinflammatory cytokine production remain unknown. Here, we screened severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genes and found that nonstructural protein 6 (NSP6) and open reading frame 7a (ORF7a) activated the NF-κB pathway. NSP6 and ORF7a interacted with transforming growth factor β-activated kinase 1 (TAK1), and knockout (KO) of TAK1 or NF-κB essential modulator (NEMO) abolished NF-κB activation by NSP6 and ORF7a. Interestingly, K61 of NSP6 was conjugated to K63-linked polyubiquitin chains by the E3 ubiquitin ligase tripartite motif-containing 13, and this polyubiquitination of NSP6 appeared crucial for recruitment of NEMO to the NSP6-TAK1 complex and NF-κB activation. On the other hand, ring finger protein 121 (RNF121) was required for the polyubiquitination of ORF7a. Knockdown of RNF121 significantly decreased ORF7a binding of TAK1 and NEMO, resulting in the suppression of NF-κB activation. Taken together, our results provide novel molecular insights into the pathogenesis of SARS-CoV-2 and the host immune response to SARS-CoV-2 infection. IMPORTANCE The detailed molecular basis of the induction of proinflammatory cytokines and chemokines by SARS-CoV-2 is unclear, although such induction is clearly related to the severity of COVID-19. Here, we show that SARS-CoV-2 NSP6 and ORF7a lead to NF-κB activation through associations with TAK1. K63-linked polyubiquitination of NSP6 and ORF7a by TRIM13 and RNF121, respectively, appears essential for NF-κB activation. These results suggest that inhibition of the NSP6 and ORF7a gene products may reduce the severity of COVID-19 symptoms by decreasing proinflammatory cytokine levels.
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Affiliation(s)
- Hironori Nishitsuji
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Aichi, Japan
| | - Satoko Iwahori
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Aichi, Japan
| | - Mariko Ohmori
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Aichi, Japan
| | - Kunitada Shimotohno
- The Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, Chiba, Japan
| | - Takayuki Murata
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Aichi, Japan
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Yamazaki T, Yamamoto T, Hirose T. Micellization: A new principle in the formation of biomolecular condensates. Front Mol Biosci 2022; 9:974772. [PMID: 36106018 PMCID: PMC9465675 DOI: 10.3389/fmolb.2022.974772] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 07/20/2022] [Indexed: 11/18/2022] Open
Abstract
Phase separation is a fundamental mechanism for compartmentalization in cells and leads to the formation of biomolecular condensates, generally containing various RNA molecules. RNAs are biomolecules that can serve as suitable scaffolds for biomolecular condensates and determine their forms and functions. Many studies have focused on biomolecular condensates formed by liquid-liquid phase separation (LLPS), one type of intracellular phase separation mechanism. We recently identified that paraspeckle nuclear bodies use an intracellular phase separation mechanism called micellization of block copolymers in their formation. The paraspeckles are scaffolded by NEAT1_2 long non-coding RNAs (lncRNAs) and their partner RNA-binding proteins (NEAT1_2 RNA-protein complexes [RNPs]). The NEAT1_2 RNPs act as block copolymers and the paraspeckles assemble through micellization. In LLPS, condensates grow without bound as long as components are available and typically have spherical shapes to minimize surface tension. In contrast, the size, shape, and internal morphology of the condensates are more strictly controlled in micellization. Here, we discuss the potential importance and future perspectives of micellization of block copolymers of RNPs in cells, including the construction of designer condensates with optimal internal organization, shape, and size according to design guidelines of block copolymers.
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Affiliation(s)
- Tomohiro Yamazaki
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
| | - Tetsuya Yamamoto
- Institute for Chemical Reaction Design and Discovery, Hokkaido University, Sapporo, Japan
| | - Tetsuro Hirose
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
- Institute for Open and Transdisciplinary Research Initiatives (OTRI), Osaka University, Suita, Japan
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Gumna J, Antczak M, Adamiak RW, Bujnicki JM, Chen SJ, Ding F, Ghosh P, Li J, Mukherjee S, Nithin C, Pachulska-Wieczorek K, Ponce-Salvatierra A, Popenda M, Sarzynska J, Wirecki T, Zhang D, Zhang S, Zok T, Westhof E, Miao Z, Szachniuk M, Rybarczyk A. Computational Pipeline for Reference-Free Comparative Analysis of RNA 3D Structures Applied to SARS-CoV-2 UTR Models. Int J Mol Sci 2022; 23:ijms23179630. [PMID: 36077037 PMCID: PMC9455975 DOI: 10.3390/ijms23179630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/17/2022] [Accepted: 08/20/2022] [Indexed: 01/19/2023] Open
Abstract
RNA is a unique biomolecule that is involved in a variety of fundamental biological functions, all of which depend solely on its structure and dynamics. Since the experimental determination of crystal RNA structures is laborious, computational 3D structure prediction methods are experiencing an ongoing and thriving development. Such methods can lead to many models; thus, it is necessary to build comparisons and extract common structural motifs for further medical or biological studies. Here, we introduce a computational pipeline dedicated to reference-free high-throughput comparative analysis of 3D RNA structures. We show its application in the RNA-Puzzles challenge, in which five participating groups attempted to predict the three-dimensional structures of 5'- and 3'-untranslated regions (UTRs) of the SARS-CoV-2 genome. We report the results of this puzzle and discuss the structural motifs obtained from the analysis. All simulated models and tools incorporated into the pipeline are open to scientific and academic use.
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Affiliation(s)
- Julita Gumna
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Maciej Antczak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
- Institute of Computing Science, Poznan University of Technology, 60-965 Poznan, Poland
| | - Ryszard W. Adamiak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
- Institute of Computing Science, Poznan University of Technology, 60-965 Poznan, Poland
| | - Janusz M. Bujnicki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, 02-109 Warsaw, Poland
| | - Shi-Jie Chen
- Department of Physics, Department of Biochemistry, Institute for Data Science and Informatics, University of Missouri, Columbia, MO 65211, USA
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, USA
| | - Pritha Ghosh
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, 02-109 Warsaw, Poland
| | - Jun Li
- Department of Physics, Department of Biochemistry, Institute for Data Science and Informatics, University of Missouri, Columbia, MO 65211, USA
| | - Sunandan Mukherjee
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, 02-109 Warsaw, Poland
| | - Chandran Nithin
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, 02-109 Warsaw, Poland
- Laboratory of Computational Biology, Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw, 02-089 Warsaw, Poland
| | | | - Almudena Ponce-Salvatierra
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, 02-109 Warsaw, Poland
| | - Mariusz Popenda
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Joanna Sarzynska
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
| | - Tomasz Wirecki
- Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, 02-109 Warsaw, Poland
| | - Dong Zhang
- Department of Physics, Department of Biochemistry, Institute for Data Science and Informatics, University of Missouri, Columbia, MO 65211, USA
| | - Sicheng Zhang
- Department of Physics, Department of Biochemistry, Institute for Data Science and Informatics, University of Missouri, Columbia, MO 65211, USA
| | - Tomasz Zok
- Institute of Computing Science, Poznan University of Technology, 60-965 Poznan, Poland
| | - Eric Westhof
- Architecture et Réactivité de l’ARN, Université de Strasbourg, Institut de Biologie Moléculaire et Cellulaire du CNRS, 67084 Strasbourg, France
| | - Zhichao Miao
- Translational Research Institute of Brain and Brain-Like Intelligence, Department of Anesthesiology, Shanghai Fourth People’s Hospital Affiliated to Tongji University School of Medicine, Shanghai 200081, China
- Correspondence: (Z.M.); (A.R.)
| | - Marta Szachniuk
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
- Institute of Computing Science, Poznan University of Technology, 60-965 Poznan, Poland
| | - Agnieszka Rybarczyk
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, 61-704 Poznan, Poland
- Institute of Computing Science, Poznan University of Technology, 60-965 Poznan, Poland
- Correspondence: (Z.M.); (A.R.)
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125
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Conti BA, Oppikofer M. Biomolecular condensates: new opportunities for drug discovery and RNA therapeutics. Trends Pharmacol Sci 2022; 43:820-837. [PMID: 36028355 DOI: 10.1016/j.tips.2022.07.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 07/15/2022] [Accepted: 07/22/2022] [Indexed: 11/18/2022]
Abstract
Biomolecular condensates organize cellular functions in the absence of membranes. These membraneless organelles can form through liquid-liquid phase separation coalescing RNA and proteins into well-defined, yet dynamic, structures distinct from the surrounding cellular milieu. Numerous physiological and disease-causing processes link to biomolecular condensates, which could impact drug discovery in several ways. First, disruption of pathological condensates seeded by mutated proteins or RNAs may provide new opportunities to treat disease. Second, condensates may be leveraged to tackle difficult-to-drug targets lacking binding pockets whose function depends on phase separation. Third, condensate-resident small molecules and RNA therapeutics may display unexpected pharmacology. We discuss the potential impact of phase separation on drug discovery and RNA therapeutics, leveraging concrete examples, towards novel clinical opportunities.
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Affiliation(s)
- Brooke A Conti
- Pfizer Centers for Therapeutic Innovation, Pfizer Inc., New York, NY, USA
| | - Mariano Oppikofer
- Pfizer Centers for Therapeutic Innovation, Pfizer Inc., New York, NY, USA.
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126
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Roden C, Dai Y, Giannetti C, Seim I, Lee M, Sealfon R, McLaughlin G, Boerneke M, Iserman C, Wey S, Ekena J, Troyanskaya O, Weeks K, You L, Chilkoti A, Gladfelter A. Double-stranded RNA drives SARS-CoV-2 nucleocapsid protein to undergo phase separation at specific temperatures. Nucleic Acids Res 2022; 50:8168-8192. [PMID: 35871289 PMCID: PMC9371935 DOI: 10.1093/nar/gkac596] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 06/13/2022] [Accepted: 07/19/2022] [Indexed: 12/11/2022] Open
Abstract
Nucleocapsid protein (N-protein) is required for multiple steps in betacoronaviruses replication. SARS-CoV-2-N-protein condenses with specific viral RNAs at particular temperatures making it a powerful model for deciphering RNA sequence specificity in condensates. We identify two separate and distinct double-stranded, RNA motifs (dsRNA stickers) that promote N-protein condensation. These dsRNA stickers are separately recognized by N-protein's two RNA binding domains (RBDs). RBD1 prefers structured RNA with sequences like the transcription-regulatory sequence (TRS). RBD2 prefers long stretches of dsRNA, independent of sequence. Thus, the two N-protein RBDs interact with distinct dsRNA stickers, and these interactions impart specific droplet physical properties that could support varied viral functions. Specifically, we find that addition of dsRNA lowers the condensation temperature dependent on RBD2 interactions and tunes translational repression. In contrast RBD1 sites are sequences critical for sub-genomic (sg) RNA generation and promote gRNA compression. The density of RBD1 binding motifs in proximity to TRS-L/B sequences is associated with levels of sub-genomic RNA generation. The switch to packaging is likely mediated by RBD1 interactions which generate particles that recapitulate the packaging unit of the virion. Thus, SARS-CoV-2 can achieve biochemical complexity, performing multiple functions in the same cytoplasm, with minimal protein components based on utilizing multiple distinct RNA motifs that control N-protein interactions.
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Affiliation(s)
- Christine A Roden
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA
| | - Yifan Dai
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Catherine A Giannetti
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA
| | - Ian Seim
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Curriculum in Bioinformatics and Computational Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Applied Physical Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Myungwoon Lee
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, USA
| | - Rachel Sealfon
- Flatiron Institute, Simons Foundation, New York, NY 10010, USA
| | - Grace A McLaughlin
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Mark A Boerneke
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA
| | - Christiane Iserman
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Samuel A Wey
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA
| | - Joanne L Ekena
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Olga G Troyanskaya
- Flatiron Institute, Simons Foundation, New York, NY 10010, USA
- Department of Computer Science, Princeton University, Princeton, NJ 08540, USA
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08540, USA
| | - Kevin M Weeks
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA
| | - Lingchong You
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27708, USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Amy S Gladfelter
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA
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127
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Wei W, Bai L, Yan B, Meng W, Wang H, Zhai J, Si F, Zheng C. When liquid-liquid phase separation meets viral infections. Front Immunol 2022; 13:985622. [PMID: 36016945 PMCID: PMC9395683 DOI: 10.3389/fimmu.2022.985622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 07/20/2022] [Indexed: 11/17/2022] Open
Abstract
Eukaryotic cells have both membranous and membraneless organelles. While the formation mechanism of membranous organelles is well understood, the formation mechanism of membraneless organelles remains unknown. Many biomolecules in the cytoplasm transition from the liquid phase to the agglutinated phase are known as liquid-liquid phase separation (LLPS). The biomolecular agglomerates’ physical properties enable them to function as dynamic compartments that respond to external pressures and stimuli. Scientists have gradually recognized the importance of phase separation during viral infections. LLPS provides a powerful new framework for understanding the viral life cycle from viral replication to evasion of host immune surveillance. As a result, this review focuses on the progress of LLPS research in viral infection and immune regulation to provide clues for antiviral therapeutic strategies.
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Affiliation(s)
- Wenqiang Wei
- Kaifeng Key Laboratory of Infection and Biological Safety, School of Basic Medical Sciences, Henan University, Kaifeng, China
| | - Lu Bai
- Kaifeng Key Laboratory of Infection and Biological Safety, School of Basic Medical Sciences, Henan University, Kaifeng, China
- Department of Immunology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China
| | - Bing Yan
- Kaifeng Key Laboratory of Infection and Biological Safety, School of Basic Medical Sciences, Henan University, Kaifeng, China
| | - Weiquan Meng
- Kaifeng Key Laboratory of Infection and Biological Safety, School of Basic Medical Sciences, Henan University, Kaifeng, China
| | - Hongju Wang
- Kaifeng Key Laboratory of Infection and Biological Safety, School of Basic Medical Sciences, Henan University, Kaifeng, China
| | - Jingbo Zhai
- Medical College, Inner Mongolia Minzu University, Tongliao, China
- Key Laboratory of Zoonose Prevention and Control at Universities of Inner Mongolia Autonomous Region, Tongliao, China
| | - Fusheng Si
- Institute of Animal Science and Veterinary Medicine, Shanghai Key Laboratory of Agricultural Genetics and Breeding, Shanghai Engineering Research Center of Breeding Pig, Shanghai Academy of Agricultural Sciences, Shanghai, China
- *Correspondence: Chunfu Zheng, ; Fusheng Si,
| | - Chunfu Zheng
- Department of Immunology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, AB, Canada
- *Correspondence: Chunfu Zheng, ; Fusheng Si,
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128
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Li Y, Lu S, Gu J, Xia W, Zhang S, Zhang S, Wang Y, Zhang C, Sun Y, Lei J, Liu C, Su Z, Yang J, Peng X, Li D. SARS-CoV-2 impairs the disassembly of stress granules and promotes ALS-associated amyloid aggregation. Protein Cell 2022; 13:602-614. [PMID: 35384603 PMCID: PMC8983322 DOI: 10.1007/s13238-022-00905-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 12/27/2021] [Indexed: 02/05/2023] Open
Abstract
The nucleocapsid (N) protein of SARS-CoV-2 has been reported to have a high ability of liquid-liquid phase separation, which enables its incorporation into stress granules (SGs) of host cells. However, whether SG invasion by N protein occurs in the scenario of SARS-CoV-2 infection is unknow, neither do we know its consequence. Here, we used SARS-CoV-2 to infect mammalian cells and observed the incorporation of N protein into SGs, which resulted in markedly impaired self-disassembly but stimulated cell cellular clearance of SGs. NMR experiments further showed that N protein binds to the SG-related amyloid proteins via non-specific transient interactions, which not only expedites the phase transition of these proteins to aberrant amyloid aggregation in vitro, but also promotes the aggregation of FUS with ALS-associated P525L mutation in cells. In addition, we found that ACE2 is not necessary for the infection of SARS-CoV-2 to mammalian cells. Our work indicates that SARS-CoV-2 infection can impair the disassembly of host SGs and promote the aggregation of SG-related amyloid proteins, which may lead to an increased risk of neurodegeneration.
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Affiliation(s)
- Yichen Li
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, 200030, China
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Shuaiyao Lu
- National Kunming High-level Biosafety Primate Research Center, Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, 650031, China
- State Key Laboratory of Medical Molecular Biology, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Jinge Gu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wencheng Xia
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shengnan Zhang
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Shenqing Zhang
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, 200030, China
- School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Yan Wang
- State Key Laboratory of Biotherapy, Department of Geriatrics and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Chong Zhang
- State Key Laboratory of Biotherapy, Department of Geriatrics and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Yunpeng Sun
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jian Lei
- State Key Laboratory of Biotherapy, Department of Geriatrics and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Cong Liu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhaoming Su
- State Key Laboratory of Biotherapy, Department of Geriatrics and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, 610041, China.
| | - Juntao Yang
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100005, China.
| | - Xiaozhong Peng
- National Kunming High-level Biosafety Primate Research Center, Institute of Medical Biology, Chinese Academy of Medical Sciences and Peking Union Medical College, Kunming, 650031, China.
- State Key Laboratory of Medical Molecular Biology, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China.
| | - Dan Li
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, 200030, China.
- Bio-X-Renji Hospital Research Center, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200240, China.
- Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, Shanghai, 200240, China.
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129
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Kleer M, Mulloy RP, Robinson CA, Evseev D, Bui-Marinos MP, Castle EL, Banerjee A, Mubareka S, Mossman K, Corcoran JA. Human coronaviruses disassemble processing bodies. PLoS Pathog 2022; 18:e1010724. [PMID: 35998203 PMCID: PMC9439236 DOI: 10.1371/journal.ppat.1010724] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 09/02/2022] [Accepted: 07/04/2022] [Indexed: 11/21/2022] Open
Abstract
A dysregulated proinflammatory cytokine response is characteristic of severe coronavirus infections caused by SARS-CoV-2, yet our understanding of the underlying mechanism responsible for this imbalanced immune response remains incomplete. Processing bodies (PBs) are cytoplasmic membraneless ribonucleoprotein granules that control innate immune responses by mediating the constitutive decay or suppression of mRNA transcripts, including many that encode proinflammatory cytokines. PB formation promotes turnover or suppression of cytokine RNAs, whereas PB disassembly corresponds with the increased stability and/or translation of these cytokine RNAs. Many viruses cause PB disassembly, an event that can be viewed as a switch that rapidly relieves cytokine RNA repression and permits the infected cell to respond to viral infection. Prior to this submission, no information was known about how human coronaviruses (CoVs) impacted PBs. Here, we show SARS-CoV-2 and the common cold CoVs, OC43 and 229E, induced PB loss. We screened a SARS-CoV-2 gene library and identified that expression of the viral nucleocapsid (N) protein from SARS-CoV-2 was sufficient to mediate PB disassembly. RNA fluorescent in situ hybridization revealed that transcripts encoding TNF and IL-6 localized to PBs in control cells. PB loss correlated with the increased cytoplasmic localization of these transcripts in SARS-CoV-2 N protein-expressing cells. Ectopic expression of the N proteins from five other human coronaviruses (OC43, MERS, 229E, NL63 and SARS-CoV) did not cause significant PB disassembly, suggesting that this feature is unique to SARS-CoV-2 N protein. These data suggest that SARS-CoV-2-mediated PB disassembly contributes to the dysregulation of proinflammatory cytokine production observed during severe SARS-CoV-2 infection.
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Affiliation(s)
- Mariel Kleer
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Rory P. Mulloy
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Carolyn-Ann Robinson
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Danyel Evseev
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Maxwell P. Bui-Marinos
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Elizabeth L. Castle
- School of Biomedical Engineering, University of British Columbia, Vancouver, British Columbia, Canada
| | - Arinjay Banerjee
- Vaccine and Infectious Disease Organization, University of Saskatchewan; Saskatoon, Saskatchewan, Canada
- Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan; Saskatoon, Saskatchewan, Canada
- Department of Biology, University of Waterloo; Waterloo, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Samira Mubareka
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
- Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Karen Mossman
- Department of Medicine, Master University, Hamilton, Ontario, Canada
- Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Jennifer A. Corcoran
- Microbiology, Immunology and Infectious Diseases Department, University of Calgary, Calgary, Alberta, Canada
- Charbonneau Cancer Research Institute, University of Calgary, Calgary, Alberta, Canada
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
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130
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Length-dependent motions of SARS-CoV-2 frameshifting RNA pseudoknot and alternative conformations suggest avenues for frameshifting suppression. Nat Commun 2022; 13:4284. [PMID: 35879278 PMCID: PMC9310368 DOI: 10.1038/s41467-022-31353-w] [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: 12/10/2021] [Accepted: 06/10/2022] [Indexed: 12/16/2022] Open
Abstract
The SARS-CoV-2 frameshifting element (FSE), a highly conserved mRNA region required for correct translation of viral polyproteins, defines an excellent therapeutic target against Covid-19. As discovered by our prior graph-theory analysis with SHAPE experiments, the FSE adopts a heterogeneous, length-dependent conformational landscape consisting of an assumed 3-stem H-type pseudoknot (graph motif 3_6), and two alternative motifs (3_3 and 3_5). Here, for the first time, we build and simulate, by microsecond molecular dynamics, 30 models for all three motifs plus motif-stabilizing mutants at different lengths. Our 3_6 pseudoknot systems, which agree with experimental structures, reveal interconvertible L and linear conformations likely related to ribosomal pausing and frameshifting. The 3_6 mutant inhibits this transformation and could hamper frameshifting. Our 3_3 systems exhibit length-dependent stem interactions that point to a potential transition pathway connecting the three motifs during ribosomal elongation. Together, our observations provide new insights into frameshifting mechanisms and anti-viral strategies.
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131
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Deroubaix A, Kramvis A. Imaging Techniques: Essential Tools for the Study of SARS-CoV-2 Infection. Front Cell Infect Microbiol 2022; 12:794264. [PMID: 35937687 PMCID: PMC9355083 DOI: 10.3389/fcimb.2022.794264] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 06/21/2022] [Indexed: 01/08/2023] Open
Abstract
The world has seen the emergence of a new virus in 2019, SARS-CoV-2, causing the COVID-19 pandemic and millions of deaths worldwide. Microscopy can be much more informative than conventional detection methods such as RT-PCR. This review aims to present the up-to-date microscopy observations in patients, the in vitro studies of the virus and viral proteins and their interaction with their host, discuss the microscopy techniques for detection and study of SARS-CoV-2, and summarize the reagents used for SARS-CoV-2 detection. From basic fluorescence microscopy to high resolution techniques and combined technologies, this article shows the power and the potential of microscopy techniques, especially in the field of virology.
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Affiliation(s)
- Aurélie Deroubaix
- Hepatitis Virus Diversity Research Unit, Department of Internal Medicine, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Life Sciences Imaging Facility, University of the Witwatersrand, Johannesburg, South Africa
| | - Anna Kramvis
- Hepatitis Virus Diversity Research Unit, Department of Internal Medicine, School of Clinical Medicine, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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Kar M, Dar F, Welsh TJ, Vogel LT, Kühnemuth R, Majumdar A, Krainer G, Franzmann TM, Alberti S, Seidel CAM, Knowles TPJ, Hyman AA, Pappu RV. Phase-separating RNA-binding proteins form heterogeneous distributions of clusters in subsaturated solutions. Proc Natl Acad Sci U S A 2022; 119:e2202222119. [PMID: 35787038 DOI: 10.1101/2022.02.03.478969] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Abstract
Macromolecular phase separation is thought to be one of the processes that drives the formation of membraneless biomolecular condensates in cells. The dynamics of phase separation are thought to follow the tenets of classical nucleation theory, and, therefore, subsaturated solutions should be devoid of clusters with more than a few molecules. We tested this prediction using in vitro biophysical studies to characterize subsaturated solutions of phase-separating RNA-binding proteins with intrinsically disordered prion-like domains and RNA-binding domains. Surprisingly, and in direct contradiction to expectations from classical nucleation theory, we find that subsaturated solutions are characterized by the presence of heterogeneous distributions of clusters. The distributions of cluster sizes, which are dominated by small species, shift continuously toward larger sizes as protein concentrations increase and approach the saturation concentration. As a result, many of the clusters encompass tens to hundreds of molecules, while less than 1% of the solutions are mesoscale species that are several hundred nanometers in diameter. We find that cluster formation in subsaturated solutions and phase separation in supersaturated solutions are strongly coupled via sequence-encoded interactions. We also find that cluster formation and phase separation can be decoupled using solutes as well as specific sets of mutations. Our findings, which are concordant with predictions for associative polymers, implicate an interplay between networks of sequence-specific and solubility-determining interactions that, respectively, govern cluster formation in subsaturated solutions and the saturation concentrations above which phase separation occurs.
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Affiliation(s)
- Mrityunjoy Kar
- Max Planck Institute of Cell Biology and Genetics, 01307 Dresden, Germany
| | - Furqan Dar
- Department of Physics, Washington University in St. Louis, St. Louis, MO 63130
| | - Timothy J Welsh
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, United Kingdom
| | - Laura T Vogel
- Department of Molecular Physical Chemistry, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Ralf Kühnemuth
- Department of Molecular Physical Chemistry, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Anupa Majumdar
- Max Planck Institute of Cell Biology and Genetics, 01307 Dresden, Germany
| | - Georg Krainer
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, United Kingdom
| | - Titus M Franzmann
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01069 Dresden, Germany
| | - Simon Alberti
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01069 Dresden, Germany
| | - Claus A M Seidel
- Department of Molecular Physical Chemistry, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Tuomas P J Knowles
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, United Kingdom
- Cavendish Laboratory, University of Cambridge, CB3 0HE Cambridge, United Kingdom
| | - Anthony A Hyman
- Max Planck Institute of Cell Biology and Genetics, 01307 Dresden, Germany
| | - Rohit V Pappu
- Department of Biomedical Engineering, Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO 63130
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133
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Kar M, Dar F, Welsh TJ, Vogel LT, Kühnemuth R, Majumdar A, Krainer G, Franzmann TM, Alberti S, Seidel CAM, Knowles TPJ, Hyman AA, Pappu RV. Phase-separating RNA-binding proteins form heterogeneous distributions of clusters in subsaturated solutions. Proc Natl Acad Sci U S A 2022; 119:e2202222119. [PMID: 35787038 PMCID: PMC9282234 DOI: 10.1073/pnas.2202222119] [Citation(s) in RCA: 99] [Impact Index Per Article: 49.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 05/26/2022] [Indexed: 12/14/2022] Open
Abstract
Macromolecular phase separation is thought to be one of the processes that drives the formation of membraneless biomolecular condensates in cells. The dynamics of phase separation are thought to follow the tenets of classical nucleation theory, and, therefore, subsaturated solutions should be devoid of clusters with more than a few molecules. We tested this prediction using in vitro biophysical studies to characterize subsaturated solutions of phase-separating RNA-binding proteins with intrinsically disordered prion-like domains and RNA-binding domains. Surprisingly, and in direct contradiction to expectations from classical nucleation theory, we find that subsaturated solutions are characterized by the presence of heterogeneous distributions of clusters. The distributions of cluster sizes, which are dominated by small species, shift continuously toward larger sizes as protein concentrations increase and approach the saturation concentration. As a result, many of the clusters encompass tens to hundreds of molecules, while less than 1% of the solutions are mesoscale species that are several hundred nanometers in diameter. We find that cluster formation in subsaturated solutions and phase separation in supersaturated solutions are strongly coupled via sequence-encoded interactions. We also find that cluster formation and phase separation can be decoupled using solutes as well as specific sets of mutations. Our findings, which are concordant with predictions for associative polymers, implicate an interplay between networks of sequence-specific and solubility-determining interactions that, respectively, govern cluster formation in subsaturated solutions and the saturation concentrations above which phase separation occurs.
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Affiliation(s)
- Mrityunjoy Kar
- Max Planck Institute of Cell Biology and Genetics, 01307 Dresden, Germany
| | - Furqan Dar
- Department of Physics, Washington University in St. Louis, St. Louis, MO 63130
| | - Timothy J. Welsh
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, United Kingdom
| | - Laura T. Vogel
- Department of Molecular Physical Chemistry, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Ralf Kühnemuth
- Department of Molecular Physical Chemistry, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Anupa Majumdar
- Max Planck Institute of Cell Biology and Genetics, 01307 Dresden, Germany
| | - Georg Krainer
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, United Kingdom
| | - Titus M. Franzmann
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01069 Dresden, Germany
| | - Simon Alberti
- Biotechnology Center, Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, 01069 Dresden, Germany
| | - Claus A. M. Seidel
- Department of Molecular Physical Chemistry, Heinrich Heine University, 40225 Düsseldorf, Germany
| | - Tuomas P. J. Knowles
- Centre for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, CB2 1EW Cambridge, United Kingdom
- Cavendish Laboratory, University of Cambridge, CB3 0HE Cambridge, United Kingdom
| | - Anthony A. Hyman
- Max Planck Institute of Cell Biology and Genetics, 01307 Dresden, Germany
| | - Rohit V. Pappu
- Department of Biomedical Engineering, Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO 63130
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134
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Lessons Learned and Yet-to-Be Learned on the Importance of RNA Structure in SARS-CoV-2 Replication. Microbiol Mol Biol Rev 2022; 86:e0005721. [PMID: 35862724 PMCID: PMC9491204 DOI: 10.1128/mmbr.00057-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
SARS-CoV-2, the etiological agent responsible for the COVID-19 pandemic, is a member of the virus family Coronaviridae, known for relatively extensive (~30-kb) RNA genomes that not only encode for numerous proteins but are also capable of forming elaborate structures. As highlighted in this review, these structures perform critical functions in various steps of the viral life cycle, ultimately impacting pathogenesis and transmissibility. We examine these elements in the context of coronavirus evolutionary history and future directions for curbing the spread of SARS-CoV-2 and other potential human coronaviruses. While we focus on structures supported by a variety of biochemical, biophysical, and/or computational methods, we also touch here on recent evidence for novel structures in both protein-coding and noncoding regions of the genome, including an assessment of the potential role for RNA structure in the controversial finding of SARS-CoV-2 integration in “long COVID” patients. This review aims to serve as a consolidation of previous works on coronavirus and more recent investigation of SARS-CoV-2, emphasizing the need for improved understanding of the role of RNA structure in the evolution and adaptation of these human viruses.
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135
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Pontoriero L, Schiavina M, Korn SM, Schlundt A, Pierattelli R, Felli IC. NMR Reveals Specific Tracts within the Intrinsically Disordered Regions of the SARS-CoV-2 Nucleocapsid Protein Involved in RNA Encountering. Biomolecules 2022; 12:biom12070929. [PMID: 35883485 PMCID: PMC9312987 DOI: 10.3390/biom12070929] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 06/28/2022] [Accepted: 06/29/2022] [Indexed: 12/23/2022] Open
Abstract
The SARS-CoV-2 nucleocapsid (N) protein is crucial for the highly organized packaging and transcription of the genomic RNA. Studying atomic details of the role of its intrinsically disordered regions (IDRs) in RNA recognition is challenging due to the absence of structure and to the repetitive nature of their primary sequence. IDRs are known to act in concert with the folded domains of N and here we use NMR spectroscopy to identify the priming events of N interacting with a regulatory SARS-CoV-2 RNA element. 13C-detected NMR experiments, acquired simultaneously to 1H detected ones, provide information on the two IDRs flanking the N-terminal RNA binding domain (NTD) within the N-terminal region of the protein (NTR, 1–248). We identify specific tracts of the IDRs that most rapidly sense and engage with RNA, and thus provide an atom-resolved picture of the interplay between the folded and disordered regions of N during RNA interaction.
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Affiliation(s)
- Letizia Pontoriero
- Magnetic Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”, University of Florence, Via L. Sacconi 6, Sesto Fiorentino, 50019 Florence, Italy; (L.P.); (M.S.)
| | - Marco Schiavina
- Magnetic Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”, University of Florence, Via L. Sacconi 6, Sesto Fiorentino, 50019 Florence, Italy; (L.P.); (M.S.)
| | - Sophie M. Korn
- Center for Biomolecular Magnetic Resonance (BMRZ), Institute for Molecular Biosciences, Johann Wolfgang Goethe-University, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany;
| | - Andreas Schlundt
- Center for Biomolecular Magnetic Resonance (BMRZ), Institute for Molecular Biosciences, Johann Wolfgang Goethe-University, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany;
- Correspondence: (A.S.); (R.P.); (I.C.F.)
| | - Roberta Pierattelli
- Magnetic Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”, University of Florence, Via L. Sacconi 6, Sesto Fiorentino, 50019 Florence, Italy; (L.P.); (M.S.)
- Correspondence: (A.S.); (R.P.); (I.C.F.)
| | - Isabella C. Felli
- Magnetic Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”, University of Florence, Via L. Sacconi 6, Sesto Fiorentino, 50019 Florence, Italy; (L.P.); (M.S.)
- Correspondence: (A.S.); (R.P.); (I.C.F.)
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136
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Wei C, Li M, Li X, Lyu J, Zhu X. Phase Separation: "The Master Key" to Deciphering the Physiological and Pathological Functions of Cells. Adv Biol (Weinh) 2022; 6:e2200006. [PMID: 35514065 DOI: 10.1002/adbi.202200006] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 03/25/2022] [Indexed: 01/28/2023]
Abstract
Phase separation is a hot research field at present. It involves almost all aspects of cells and plays a significant role in cells, promising to be "a master key" in unlocking the mysteries of nature. In this review, the factors that affect phase separation are introduced, such as own component, electrostatic interaction, and chemical modification. Furthermore, the physiological roles of phase separation in cells, including molecules transport channel, gene expression and regulation, cellular division and differentiation, stress response, proteins refolding and degradation, cell connections, construction of skin barrier, and cell signals transmission, are highlighted. However, the disorder of phase separation leads to pathological condensates, which are associated with neurodegenerative diseases, tumors, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This relationship is considered the potential target for developing corresponded drugs and therapy. Some drugs targeting phase separation have improved meaningful, such as tankyrase, lipoamide, oligonucleotides, elvitagravir, nilotinib, CVL218, PJ34. All in all, mystery phase separation provides a new viewpoint for researchers to explore cells, and is expected to solve many unknown phenomena in nature.
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Affiliation(s)
- Chuzhong Wei
- School of Laboratory Medicine and Biological Engineering, Hangzhou Medical College, Hangzhou, 310053, China.,Zhu's Innovation Team, Guangdong Medical University, Zhanjiang, 523808, China
| | - Mingdong Li
- Department of Gastroenterology, Zibo Central Hospital, Zibo, 255000, China
| | - Xinming Li
- Zhu's Innovation Team, Guangdong Medical University, Zhanjiang, 523808, China
| | - Jianxin Lyu
- School of Laboratory Medicine and Biological Engineering, Hangzhou Medical College, Hangzhou, 310053, China
| | - Xiao Zhu
- School of Laboratory Medicine and Biological Engineering, Hangzhou Medical College, Hangzhou, 310053, China.,Zhu's Innovation Team, Guangdong Medical University, Zhanjiang, 523808, China
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137
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Kung YA, Lee KM, Chiang HJ, Huang SY, Wu CJ, Shih SR. Molecular Virology of SARS-CoV-2 and Related Coronaviruses. Microbiol Mol Biol Rev 2022; 86:e0002621. [PMID: 35343760 PMCID: PMC9199417 DOI: 10.1128/mmbr.00026-21] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The global COVID-19 pandemic continues to threaten the lives of hundreds of millions of people, with a severe negative impact on the global economy. Although several COVID-19 vaccines are currently being administered, none of them is 100% effective. Moreover, SARS-CoV-2 variants remain an important worldwide public health issue. Hence, the accelerated development of efficacious antiviral agents is urgently needed. Coronavirus depends on various host cell factors for replication. An ongoing research objective is the identification of host factors that could be exploited as targets for drugs and compounds effective against SARS-CoV-2. In the present review, we discuss the molecular mechanisms of SARS-CoV-2 and related coronaviruses, focusing on the host factors or pathways involved in SARS-CoV-2 replication that have been identified by genome-wide CRISPR screening.
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Affiliation(s)
- Yu-An Kung
- Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Kuo-Ming Lee
- Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Division of Infectious Diseases, Department of Pediatrics, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Huan-Jung Chiang
- Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Sheng-Yu Huang
- Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chung-Jung Wu
- Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Shin-Ru Shih
- Research Center for Emerging Viral Infections, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Department of Laboratory Medicine, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan
- Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan
- Research Center for Food and Cosmetic Safety, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan
- Graduate Institute of Health Industry Technology, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan
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138
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Conformational ensemble of the full-length SARS-CoV-2 nucleocapsid (N) protein based on molecular simulations and SAXS data. Biophys Chem 2022; 288:106843. [PMID: 35696898 PMCID: PMC9172258 DOI: 10.1016/j.bpc.2022.106843] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/10/2022] [Accepted: 06/02/2022] [Indexed: 11/02/2022]
Abstract
The nucleocapsid protein of the SARS-CoV-2 virus comprises two RNA-binding domains and three regions that are intrinsically disordered. While the structures of the RNA-binding domains have been solved using protein crystallography and NMR, current knowledge of the conformations of the full-length nucleocapsid protein is rather limited. To fill in this knowledge gap, we combined coarse-grained molecular simulations with data from small-angle X-ray scattering (SAXS) experiments using the ensemble refinement of SAXS (EROS) method. Our results show that the dimer of the full-length nucleocapsid protein exhibits large conformational fluctuations with its radius of gyration ranging from about 4 to 8 nm. The RNA-binding domains do not make direct contacts. The disordered region that links these two domains comprises a hydrophobic α-helix which makes frequent and nonspecific contacts with the RNA-binding domains. Each of the intrinsically disordered regions adopts conformations that are locally compact, yet on average, much more extended than Gaussian chains of equivalent lengths. We offer a detailed picture of the conformational ensemble of the nucleocapsid protein dimer under near-physiological conditions, which will be important for understanding the nucleocapsid assembly process.
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139
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Dang M, Song J. A review of the effects of ATP and hydroxychloroquine on the phase separation of the SARS-CoV-2 nucleocapsid protein. Biophys Rev 2022; 14:709-715. [PMID: 35756710 PMCID: PMC9214679 DOI: 10.1007/s12551-022-00957-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 05/05/2022] [Indexed: 12/23/2022] Open
Abstract
SARS-CoV-2 is the coronavirus causing the ongoing pandemic with > 460 millions of infections and > 6 millions of deaths. SARS-CoV-2 nucleocapsid (N) is the only structural protein which plays essential roles in almost all key steps of the viral life cycle with its diverse functions depending on liquid-liquid phase separation (LLPS) driven by interacting with various nucleic acids. The 419-residue N protein is highly conserved in all variants including delta and omicron, and composed of both folded N-/C-terminal domains (NTD/CTD) as well as three long intrinsically disordered regions (IDRs). Recent results have suggested that its CTD and IDRs are also cryptic nucleic acid-binding domains. In this context, any small molecules capable of interfering in its interaction with nucleic acids are anticipated to modulate its LLPS and associated functions. Indeed, ATP, the energy currency existing at very high concentrations (2-12 mM) in all living cells but absent in viruses, modulates LLPS of N protein, and consequently appears to be evolutionarily hijacked by SARS-CoV-2 to promote its life cycle. Hydroxychloroquine (HCQ) has been also shown to specifically bind NTD and CTD to inhibit their interactions with nucleic acids, as well as to disrupt LLPS. Particularly, the unique structure of the HCQ-CTD complex offers a promising strategy for further design of anti-SARS-CoV-2 drugs with better affinity and specificity. The finding may indicate that LLPS is indeed druggable by small molecules, thus opening up a promising direction for drug discovery/design by targeting LLPS in general.
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Affiliation(s)
- Mei Dang
- Department of Biological Sciences, Faculty of Science, National University of Singapore; 10 Kent Ridge Crescent, Singapore, 119260 Singapore
| | - Jianxing Song
- Department of Biological Sciences, Faculty of Science, National University of Singapore; 10 Kent Ridge Crescent, Singapore, 119260 Singapore
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140
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Newly Emerged Antiviral Strategies for SARS-CoV-2: From Deciphering Viral Protein Structural Function to the Development of Vaccines, Antibodies, and Small Molecules. Int J Mol Sci 2022; 23:ijms23116083. [PMID: 35682761 PMCID: PMC9181103 DOI: 10.3390/ijms23116083] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 05/20/2022] [Accepted: 05/27/2022] [Indexed: 01/09/2023] Open
Abstract
Coronavirus disease 2019 (COVID-19) caused by the infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become the most severe health crisis, causing extraordinary economic disruption worldwide. SARS-CoV-2 is a single-stranded RNA-enveloped virus. The process of viral replication and particle packaging is finished in host cells. Viral proteins, including both structural and nonstructural proteins, play important roles in the viral life cycle, which also provides the targets of treatment. Therefore, a better understanding of the structural function of virus proteins is crucial to speed up the development of vaccines and therapeutic strategies. Currently, the structure and function of proteins encoded by the SARS-CoV-2 genome are reviewed by several studies. However, most of them are based on the analysis of SARS-CoV-1 particles, lacking a systematic review update for SARS-CoV-2. Here, we specifically focus on the structure and function of proteins encoded by SARS-CoV-2. Viral proteins that contribute to COVID-19 infection and disease pathogenesis are reviewed according to the most recent research findings. The structure-function correlation of viral proteins provides a fundamental rationale for vaccine development and targeted therapy. Then, current antiviral vaccines are updated, such as inactive viral vaccines and protein-based vaccines and DNA, mRNA, and circular RNA vaccines. A summary of other therapeutic options is also reviewed, including monoclonal antibodies such as a cross-neutralizer antibody, a constructed cobinding antibody, a dual functional monoclonal antibody, an antibody cocktail, and an engineered bispecific antibody, as well as peptide-based inhibitors, chemical compounds, and clustered regularly interspaced short palindromic repeats (CRISPR) exploration. Overall, viral proteins and their functions provide the basis for targeted therapy and vaccine development.
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141
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Carlson CR, Adly AN, Bi M, Cheng Y, Morgan DO. Reconstitution of the SARS-CoV-2 ribonucleosome provides insights into genomic RNA packaging and regulation by phosphorylation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2022:2022.05.23.493138. [PMID: 35664996 PMCID: PMC9164447 DOI: 10.1101/2022.05.23.493138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The nucleocapsid (N) protein of coronaviruses is responsible for compaction of the ∼30-kb RNA genome in the ∼100-nm virion. Cryo-electron tomography suggests that each virion contains 35-40 viral ribonucleoprotein (vRNP) complexes, or ribonucleosomes, arrayed along the genome. There is, however, little mechanistic understanding of the vRNP complex. Here, we show that N protein, when combined with viral RNA fragments in vitro, forms cylindrical 15-nm particles similar to the vRNP structures observed within coronavirus virions. These vRNPs form in the presence of stem-loop-containing RNA and depend on regions of N protein that promote protein-RNA and protein-protein interactions. Phosphorylation of N protein in its disordered serine/arginine (SR) region weakens these interactions and disrupts vRNP assembly. We propose that unmodified N binds stem-loop-rich regions in genomic RNA to form compact vRNP complexes within the nucleocapsid, while phosphorylated N maintains uncompacted viral RNA to promote the protein's transcriptional function.
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Affiliation(s)
| | - Armin N. Adly
- Department of Physiology, University of California, San Francisco CA 94143
| | - Maxine Bi
- Department of Biochemistry & Biophysics, University of California, San Francisco CA 94143
| | - Yifan Cheng
- Department of Biochemistry & Biophysics, University of California, San Francisco CA 94143
| | - David O. Morgan
- Department of Physiology, University of California, San Francisco CA 94143
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142
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Characterization of RNA content in individual phase-separated coacervate microdroplets. Nat Commun 2022; 13:2626. [PMID: 35551426 PMCID: PMC9098875 DOI: 10.1038/s41467-022-30158-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 04/05/2022] [Indexed: 11/08/2022] Open
Abstract
Condensates formed by complex coacervation are hypothesized to have played a crucial part during the origin-of-life. In living cells, condensation organizes biomolecules into a wide range of membraneless compartments. Although RNA is a key component of biological condensates and the central component of the RNA world hypothesis, little is known about what determines RNA accumulation in condensates and to which extend single condensates differ in their RNA composition. To address this, we developed an approach to read the RNA content from single synthetic and protein-based condensates using high-throughput sequencing. We find that certain RNAs efficiently accumulate in condensates. These RNAs are strongly enriched in sequence motifs which show high sequence similarity to short interspersed elements (SINEs). We observe similar results for protein-derived condensates, demonstrating applicability across different in vitro reconstituted membraneless organelles. Thus, our results provide a new inroad to explore the RNA content of phase-separated droplets at single condensate resolution.
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143
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Vandelli A, Vocino G, Tartaglia GG. Phase Separation Drives SARS-CoV-2 Replication: A Hypothesis. Front Mol Biosci 2022; 9:893067. [PMID: 35647024 PMCID: PMC9132231 DOI: 10.3389/fmolb.2022.893067] [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: 03/09/2022] [Accepted: 04/25/2022] [Indexed: 12/28/2022] Open
Abstract
Identifying human proteins that interact with SARS-CoV-2 genome is important to understand its replication and to identify therapeutic strategies. Recent studies have unveiled protein interactions of SARS-COV-2 in different cell lines and through a number of high-throughput approaches. Here, we carried out a comparative analysis of four experimental and one computational studies to characterize the interactions of SARS-CoV-2 genomic RNA. Although hundreds of interactors have been identified, only twenty-one appear in all the experiments and show a strong propensity to bind. This set of interactors includes stress granule forming proteins, pre-mRNA regulators and elements involved in the replication process. Our calculations indicate that DDX3X and several editases bind the 5′ end of SARS-CoV-2, a regulatory region previously reported to attract a large number of proteins. The small overlap among experimental datasets suggests that SARS-CoV-2 genome establishes stable interactions only with few interactors, while many proteins bind less tightly. In analogy to what has been previously reported for Xist non-coding RNA, we propose a mechanism of phase separation through which SARS-CoV-2 progressively sequesters human proteins hijacking the host immune response.
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Affiliation(s)
- Andrea Vandelli
- Department of Biochemistry and Molecular Biology, Universitat Autònoma de Barcelona, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Giovanni Vocino
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Gian Gaetano Tartaglia
- Center for Human Technologies, Istituto Italiano di Tecnologia, Genova, Italy
- Department of Biology ‘Charles Darwin’, Sapienza University of Rome, Rome, Italy
- Institucio Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
- *Correspondence: Gian Gaetano Tartaglia,
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Fitzgerald K, Chen Y, Lei X, Jiang Z, Humphries F, Mustone N, Ramos I, Mutetwa T, Fernandez-Sesma A. CNBP restricts SARS-CoV2 by regulating IFN and disrupting RNA-protein condensates. RESEARCH SQUARE 2022:rs.3.rs-1576788. [PMID: 35547851 PMCID: PMC9094105 DOI: 10.21203/rs.3.rs-1576788/v1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) evades antiviral immunity through the expression of viral proteins that block detection, signaling, interferon (IFN) induction, and IFN-stimulated gene (ISG) expression1, 2. Weak induction of type I IFNs is associated with a hyperinflammatory response in patients that develop severe COVID-193, 4, 5. Here we uncover a role for cellular nucleic acid-binding protein (CNBP) in restricting SARS-CoV-2. Typically, CNBP resides in the cytosol and, in response to RNA sensing pathways, undergoes phosphorylation, nuclear translocation, and IFNβ enhancer DNA binding to turn on IFNβ gene transcription. In SARS-CoV-2-infected cells CNBP coordinates IFNβ gene transcription. In addition, CNBP binds SARS-CoV-2 viral RNA directly. CNBP competes with the nucleocapsid (N) protein and prevents viral RNA and nucleocapsid protein from undergoing liquid-liquid phase separation (LLPS) forming condensates critical for viral replication. Consequently, cells and animals lacking CNBP have higher viral loads and CNBP-deficient mice succumb rapidly to infection. Altogether, these findings identify CNBP as a key antiviral factor for SARS-CoV-2, functioning both as a regulator of antiviral IFN gene expression and a cell intrinsic restriction factor that disrupts LLPS to limit viral replication and spread.
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Affiliation(s)
| | | | - Xuqiu Lei
- University of Massachusetts Medical School
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145
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Zhao H, Nguyen A, Wu D, Li Y, Hassan SA, Chen J, Shroff H, Piszczek G, Schuck P. Plasticity in structure and assembly of SARS-CoV-2 nucleocapsid protein. PNAS NEXUS 2022; 1:pgac049. [PMID: 35783502 PMCID: PMC9235412 DOI: 10.1093/pnasnexus/pgac049] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 04/19/2022] [Indexed: 02/06/2023]
Abstract
Worldwide SARS-CoV-2 sequencing efforts track emerging mutations in its spike protein, as well as characteristic mutations in other viral proteins. Besides their epidemiological importance, the observed SARS-CoV-2 sequences present an ensemble of viable protein variants, and thereby a source of information on viral protein structure and function. Charting the mutational landscape of the nucleocapsid (N) protein that facilitates viral assembly, we observe variability exceeding that of the spike protein, with more than 86% of residues that can be substituted, on average by three to four different amino acids. However, mutations exhibit an uneven distribution that tracks known structural features but also reveals highly protected stretches of unknown function. One of these conserved regions is in the central disordered linker proximal to the N-G215C mutation that has become dominant in the Delta variant, outcompeting G215 variants without further spike or N-protein substitutions. Structural models suggest that the G215C mutation stabilizes conserved transient helices in the disordered linker serving as protein-protein interaction interfaces. Comparing Delta variant N-protein to its ancestral version in biophysical experiments, we find a significantly more compact and less disordered structure. N-G215C exhibits substantially stronger self-association, shifting the unliganded protein from a dimeric to a tetrameric oligomeric state, which leads to enhanced coassembly with nucleic acids. This suggests that the sequence variability of N-protein is mirrored by high plasticity of N-protein biophysical properties, which we hypothesize can be exploited by SARS-CoV-2 to achieve greater efficiency of viral assembly, and thereby enhanced infectivity.
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Affiliation(s)
- Huaying Zhao
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ai Nguyen
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Di Wu
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yan Li
- Proteomics Core Facility, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sergio A Hassan
- Bioinformatics and Computational Biosciences Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jiji Chen
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD 20892, USA
| | - Hari Shroff
- Advanced Imaging and Microscopy Resource, National Institutes of Health, Bethesda, MD 20892, USA
- Laboratory of High Resolution Optical Imaging, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Grzegorz Piszczek
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Peter Schuck
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
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146
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Laghmach R, Alshareedah I, Pham M, Raju M, Banerjee PR, Potoyan DA. RNA chain length and stoichiometry govern surface tension and stability of protein-RNA condensates. iScience 2022; 25:104105. [PMID: 35378855 PMCID: PMC8976129 DOI: 10.1016/j.isci.2022.104105] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 02/23/2022] [Accepted: 03/15/2022] [Indexed: 12/28/2022] Open
Abstract
Proteomic studies have shown that cellular condensates are frequently enriched in diverse RNA molecules, which is suggestive of mechanistic links between phase separation and transcriptional activities. Here, we report a systematic experimental and computational study of thermodynamic landscapes and interfacial properties of protein-RNA condensates. We have studied the affinity of protein-RNA condensation as a function of variable RNA sequence length and RNA-protein stoichiometry under different ionic environments and external crowding. We have chosen the PolyU sequences for RNA and arginine/glycine-rich intrinsically disordered peptide (RGG) for proteins as a model system of RNA-protein condensates, which we then investigate through in vitro microscopy measurements and coarse-grained molecular dynamics simulations. We find that crowding and RNA chain length can have a major stabilizing effect on the condensation. We also find that the RNA-protein charge ratio is a crucial variable controlling stability, interfacial properties, and the reentrant phase behavior of RGG-RNA mixtures.
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Affiliation(s)
- Rabia Laghmach
- Department of Chemistry, Iowa State University, Ames, IA 50011, USA
| | | | - Matthew Pham
- Department of Chemistry, Iowa State University, Ames, IA 50011, USA
| | | | - Priya R. Banerjee
- Department of Physics, University at Buffalo, Buffalo, NY 14260, USA
| | - Davit A. Potoyan
- Department of Chemistry, Iowa State University, Ames, IA 50011, USA
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147
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Caruso IP, Dos Santos Almeida V, do Amaral MJ, de Andrade GC, de Araújo GR, de Araújo TS, de Azevedo JM, Barbosa GM, Bartkevihi L, Bezerra PR, Dos Santos Cabral KM, de Lourenço IO, Malizia-Motta CLF, de Luna Marques A, Mebus-Antunes NC, Neves-Martins TC, de Sá JM, Sanches K, Santana-Silva MC, Vasconcelos AA, da Silva Almeida M, de Amorim GC, Anobom CD, Da Poian AT, Gomes-Neto F, Pinheiro AS, Almeida FCL. Insights into the specificity for the interaction of the promiscuous SARS-CoV-2 nucleocapsid protein N-terminal domain with deoxyribonucleic acids. Int J Biol Macromol 2022; 203:466-480. [PMID: 35077748 PMCID: PMC8783401 DOI: 10.1016/j.ijbiomac.2022.01.121] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 01/17/2022] [Accepted: 01/18/2022] [Indexed: 12/23/2022]
Abstract
The SARS-CoV-2 nucleocapsid protein (N) is a multifunctional promiscuous nucleic acid-binding protein, which plays a major role in nucleocapsid assembly and discontinuous RNA transcription, facilitating the template switch of transcriptional regulatory sequences (TRS). Here, we dissect the structural features of the N protein N-terminal domain (N-NTD) and N-NTD plus the SR-rich motif (N-NTD-SR) upon binding to single and double-stranded TRS DNA, as well as their activities for dsTRS melting and TRS-induced liquid-liquid phase separation (LLPS). Our study gives insights on the specificity for N-NTD(-SR) interaction with TRS. We observed an approximation of the triple-thymidine (TTT) motif of the TRS to β-sheet II, giving rise to an orientation difference of ~25° between dsTRS and non-specific sequence (dsNS). It led to a local unfavorable energetic contribution that might trigger the melting activity. The thermodynamic parameters of binding of ssTRSs and dsTRS suggested that the duplex dissociation of the dsTRS in the binding cleft is entropically favorable. We showed a preference for TRS in the formation of liquid condensates when compared to NS. Moreover, our results on DNA binding may serve as a starting point for the design of inhibitors, including aptamers, against N, a possible therapeutic target essential for the virus infectivity.
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Affiliation(s)
- Icaro Putinhon Caruso
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São José do Rio Preto, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil.
| | - Vitor Dos Santos Almeida
- National Center of Nuclear Magnetic Resonance (CNRMN), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Mariana Juliani do Amaral
- Faculty of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Protein Advanced Biochemistry (PAB), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Guilherme Caldas de Andrade
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; National Center of Nuclear Magnetic Resonance (CNRMN), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Gabriela Rocha de Araújo
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; National Center of Nuclear Magnetic Resonance (CNRMN), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Talita Stelling de Araújo
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Protein Advanced Biochemistry (PAB), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Jéssica Moreira de Azevedo
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Protein Advanced Biochemistry (PAB), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Glauce Moreno Barbosa
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; National Center of Nuclear Magnetic Resonance (CNRMN), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Leonardo Bartkevihi
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; National Center of Nuclear Magnetic Resonance (CNRMN), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Peter Reis Bezerra
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; National Center of Nuclear Magnetic Resonance (CNRMN), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Katia Maria Dos Santos Cabral
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Protein Advanced Biochemistry (PAB), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Isabella Otênio de Lourenço
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São José do Rio Preto, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Clara L F Malizia-Motta
- Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Aline de Luna Marques
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Multidisciplinary Center for Research in Biology (NUMPEX), Campus Duque de Caxias Federal University of Rio de Janeiro, Duque de Caxias, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Nathane Cunha Mebus-Antunes
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Thais Cristtina Neves-Martins
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Jéssica Maróstica de Sá
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São José do Rio Preto, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Karoline Sanches
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, São Paulo State University (UNESP), São José do Rio Preto, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Marcos Caique Santana-Silva
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Multidisciplinary Center for Research in Biology (NUMPEX), Campus Duque de Caxias Federal University of Rio de Janeiro, Duque de Caxias, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Ariana Azevedo Vasconcelos
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; National Center of Nuclear Magnetic Resonance (CNRMN), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Marcius da Silva Almeida
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Protein Advanced Biochemistry (PAB), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Gisele Cardoso de Amorim
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Multidisciplinary Center for Research in Biology (NUMPEX), Campus Duque de Caxias Federal University of Rio de Janeiro, Duque de Caxias, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Cristiane Dinis Anobom
- National Center of Nuclear Magnetic Resonance (CNRMN), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Andrea T Da Poian
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Francisco Gomes-Neto
- National Center of Nuclear Magnetic Resonance (CNRMN), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Laboratory of Toxinology, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Anderson S Pinheiro
- Department of Biochemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil
| | - Fabio C L Almeida
- Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; National Center of Nuclear Magnetic Resonance (CNRMN), CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Rio BioNMR Network, Rio de Janeiro, Brazil.
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148
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Seim I, Posey AE, Snead WT, Stormo BM, Klotsa D, Pappu RV, Gladfelter AS. Dilute phase oligomerization can oppose phase separation and modulate material properties of a ribonucleoprotein condensate. Proc Natl Acad Sci U S A 2022; 119:e2120799119. [PMID: 35333653 PMCID: PMC9060498 DOI: 10.1073/pnas.2120799119] [Citation(s) in RCA: 45] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 02/16/2022] [Indexed: 01/02/2023] Open
Abstract
SignificanceA large subclass of biomolecular condensates are linked to RNA regulation and are known as ribonucleoprotein (RNP) bodies. While extensive work has identified driving forces for biomolecular condensate formation, relatively little is known about forces that oppose assembly. Here, using a fungal RNP protein, Whi3, we show that a portion of its intrinsically disordered, glutamine-rich region modulates phase separation by forming transient alpha helical structures that promote the assembly of dilute phase oligomers. These oligomers detour Whi3 proteins from condensates, thereby impacting the driving forces for phase separation, the protein-to-RNA ratio in condensates, and the material properties of condensates. Our findings show how nanoscale conformational and oligomerization equilibria can influence mesoscale phase equilibria.
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Affiliation(s)
- Ian Seim
- Curriculum in Bioinformatics and Computational Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Department of Applied Physical Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Ammon E. Posey
- Department of Biomedical Engineering, Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO 63130
| | - Wilton T. Snead
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Benjamin M. Stormo
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Daphne Klotsa
- Curriculum in Bioinformatics and Computational Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Department of Applied Physical Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Rohit V. Pappu
- Department of Biomedical Engineering, Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO 63130
| | - Amy S. Gladfelter
- Curriculum in Bioinformatics and Computational Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
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149
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Abstract
Biomolecular condensates are intracellular organelles that are not bounded by membranes and often show liquid-like, dynamic material properties. They typically contain various types of proteins and nucleic acids. How the interaction of proteins and nucleic acids finally results in dynamic condensates is not fully understood. Here we use optical tweezers and fluorescence microscopy to study how the prototypical prion-like protein Fused-in-Sarcoma (FUS) condenses with individual molecules of single- and double-stranded DNA. We find that FUS adsorbs on DNA in a monolayer and hence generates an effectively sticky FUS–DNA polymer that collapses and finally forms a dynamic, reversible FUS–DNA co-condensate. We speculate that protein monolayer-based protein–nucleic acid co-condensation is a general mechanism for forming intracellular membraneless organelles. Biomolecular condensates provide distinct compartments that can localize and organize biochemistry inside cells. Recent evidence suggests that condensate formation is prevalent in the cell nucleus. To understand how different components of the nucleus interact during condensate formation is an important challenge. In particular, the physics of co-condensation of proteins together with nucleic acids remains elusive. Here we use optical tweezers to study how the prototypical prion-like protein Fused-in-Sarcoma (FUS) forms liquid-like assemblies in vitro, by co-condensing together with individual DNA molecules. Through progressive force-induced peeling of dsDNA, buffer exchange, and force measurements, we show that FUS adsorbing in a single layer on DNA effectively generates a sticky FUS–DNA polymer that can collapse to form a liquid-like FUS–DNA co-condensate. Condensation occurs at constant DNA tension for double-stranded DNA, which is a signature of phase separation. We suggest that co-condensation mediated by protein monolayer adsorption on nucleic acids is an important mechanism for intracellular compartmentalization.
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150
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Cascarina SM, Ross ED. Phase separation by the SARS-CoV-2 nucleocapsid protein: Consensus and open questions. J Biol Chem 2022; 298:101677. [PMID: 35131265 PMCID: PMC8813722 DOI: 10.1016/j.jbc.2022.101677] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 01/26/2022] [Accepted: 01/28/2022] [Indexed: 01/09/2023] Open
Abstract
In response to the recent SARS-CoV-2 pandemic, a number of labs across the world have reallocated their time and resources to better our understanding of the virus. For some viruses, including SARS-CoV-2, viral proteins can undergo phase separation: a biophysical process often related to the partitioning of protein and RNA into membraneless organelles in vivo. In this review, we discuss emerging observations of phase separation by the SARS-CoV-2 nucleocapsid (N) protein-an essential viral protein required for viral replication-and the possible in vivo functions that have been proposed for N-protein phase separation, including viral replication, viral genomic RNA packaging, and modulation of host-cell response to infection. Additionally, since a relatively large number of studies examining SARS-CoV-2 N-protein phase separation have been published in a short span of time, we take advantage of this situation to compare results from similar experiments across studies. Our evaluation highlights potential strengths and pitfalls of drawing conclusions from a single set of experiments, as well as the value of publishing overlapping scientific observations performed simultaneously by multiple labs.
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Affiliation(s)
- Sean M Cascarina
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, USA
| | - Eric D Ross
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado, USA.
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