1
|
Ginell GM, Holehouse AS. An Introduction to the Stickers-and-Spacers Framework as Applied to Biomolecular Condensates. Methods Mol Biol 2023; 2563:95-116. [PMID: 36227469 DOI: 10.1007/978-1-0716-2663-4_4] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Cellular organization is determined by a combination of membrane-bound and membrane-less biomolecular assemblies that range from clusters of tens of molecules to micrometer-sized cellular bodies. Over the last decade, membrane-less assemblies have come to be referred to as biomolecular condensates, reflecting their ability to condense specific molecules with respect to the remainder of the cell. In many cases, the physics of phase transitions provides a conceptual framework and a mathematical toolkit to describe the assembly, maintenance, and dissolution of biomolecular condensates. Among the various quantitative and qualitative models applied to understand intracellular phase transitions, the stickers-and-spacers framework offers an intuitive yet rigorous means to map biomolecular sequences and structure to the driving forces needed for higher-order assembly. This chapter introduces the fundamental concepts behind the stickers-and-spacers model, considers its application to different biological systems, and discusses limitations and misconceptions around the model.
Collapse
Affiliation(s)
- Garrett M Ginell
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA
- Center for Science & Engineering of Living Systems (CSELS), Washington University in St. Louis, St. Louis, MO, USA
| | - Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA.
- Center for Science & Engineering of Living Systems (CSELS), Washington University in St. Louis, St. Louis, MO, USA.
| |
Collapse
|
2
|
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.
Collapse
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
| |
Collapse
|
3
|
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.
Collapse
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
| |
Collapse
|
4
|
Roden CA, Gladfelter AS. Design considerations for analyzing protein translation regulation by condensates. RNA (NEW YORK, N.Y.) 2022; 28:88-96. [PMID: 34670845 PMCID: PMC8675288 DOI: 10.1261/rna.079002.121] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
One proposed role for biomolecular condensates that contain RNA is translation regulation. In several specific contexts, translation has been shown to be modulated by the presence of a phase-separating protein and under conditions which promote phase separation, and likely many more await discovery. A powerful tool for determining the rules for condensate-dependent translation is the use of engineered RNA sequences, which can serve as reporters for translation efficiency. This Perspective will discuss design features to consider in engineering RNA reporters to determine the role of phase separation in translational regulation. Specifically, we will cover (i) how to engineer RNA sequence to recapitulate native protein/RNA interactions, (ii) the advantages and disadvantages for commonly used reporter RNA sequences, and (iii) important control experiments to distinguish between binding- and condensation-dependent translational repression. The goal of this review is to promote the design and application of faithful translation reporters to demonstrate a physiological role of biomolecular condensates in translation.
Collapse
Affiliation(s)
- Christine A Roden
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27514, USA
| | - Amy S Gladfelter
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27514, USA
| |
Collapse
|
5
|
Benninger RKP, Kravets V. The physiological role of β-cell heterogeneity in pancreatic islet function. Nat Rev Endocrinol 2022; 18:9-22. [PMID: 34667280 PMCID: PMC8915749 DOI: 10.1038/s41574-021-00568-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/07/2021] [Indexed: 01/03/2023]
Abstract
Endocrine cells within the pancreatic islets of Langerhans are heterogeneous in terms of transcriptional profile, protein expression and the regulation of hormone release. Even though this heterogeneity has long been appreciated, only within the past 5 years have detailed molecular analyses led to an improved understanding of its basis. Although we are beginning to recognize why some subpopulations of endocrine cells are phenotypically different to others, arguably the most important consideration is how this heterogeneity affects the regulation of hormone release to control the homeostasis of glucose and other energy-rich nutrients. The focus of this Review is the description of how endocrine cell heterogeneity (and principally that of insulin-secreting β-cells) affects the regulation of hormone secretion within the islets of Langerhans. This discussion includes an overview of the functional characteristics of the different islet cell subpopulations and describes how they can communicate to influence islet function under basal and glucose-stimulated conditions. We further discuss how changes to the specific islet cell subpopulations or their numbers might underlie islet dysfunction in type 2 diabetes mellitus. We conclude with a discussion of several key open questions regarding the physiological role of islet cell heterogeneity.
Collapse
Affiliation(s)
- Richard K P Benninger
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
- Barbara Davis Center for Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
| | - Vira Kravets
- Department of Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
- Barbara Davis Center for Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
| |
Collapse
|