1
|
Crawford RA, Eastham M, Pool MR, Ashe MP. Orchestrated centers for the production of proteins or "translation factories". WILEY INTERDISCIPLINARY REVIEWS. RNA 2024; 15:e1867. [PMID: 39048533 DOI: 10.1002/wrna.1867] [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: 01/19/2024] [Revised: 05/20/2024] [Accepted: 06/07/2024] [Indexed: 07/27/2024]
Abstract
The mechanics of how proteins are generated from mRNA is increasingly well understood. However, much less is known about how protein production is coordinated and orchestrated within the crowded intracellular environment, especially in eukaryotic cells. Recent studies suggest that localized sites exist for the coordinated production of specific proteins. These sites have been termed "translation factories" and roles in protein complex formation, protein localization, inheritance, and translation regulation have been postulated. In this article, we review the evidence supporting the translation of mRNA at these sites, the details of their mechanism of formation, and their likely functional significance. Finally, we consider the key uncertainties regarding these elusive structures in cells. This article is categorized under: Translation Translation > Mechanisms RNA Export and Localization > RNA Localization Translation > Regulation.
Collapse
Affiliation(s)
- Robert A Crawford
- Division of Molecular and Cellular Function, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
| | - Matthew Eastham
- Division of Molecular and Cellular Function, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
| | - Martin R Pool
- Division of Molecular and Cellular Function, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
| | - Mark P Ashe
- Division of Molecular and Cellular Function, Faculty of Biology Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
| |
Collapse
|
2
|
Glauninger H, Bard JA, Wong Hickernell CJ, Airoldi EM, Li W, Singer RH, Paul S, Fei J, Sosnick TR, Wallace EWJ, Drummond DA. Transcriptome-wide mRNA condensation precedes stress granule formation and excludes stress-induced transcripts. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.15.589678. [PMID: 38659805 PMCID: PMC11042329 DOI: 10.1101/2024.04.15.589678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Stress-induced condensation of mRNA and proteins into stress granules is conserved across eukaryotes, yet the function, formation mechanisms, and relation to well-studied conserved transcriptional responses remain largely unresolved. Stress-induced exposure of ribosome-free mRNA following translational shutoff is thought to cause condensation by allowing new multivalent RNA-dependent interactions, with RNA length and associated interaction capacity driving increased condensation. Here we show that, in striking contrast, virtually all mRNA species condense in response to multiple unrelated stresses in budding yeast, length plays a minor role, and instead, stress-induced transcripts are preferentially excluded from condensates, enabling their selective translation. Using both endogenous genes and reporter constructs, we show that translation initiation blockade, rather than resulting ribosome-free RNA, causes condensation. These translation initiation-inhibited condensates (TIICs) are biochemically detectable even when stress granules, defined as microscopically visible foci, are absent or blocked. TIICs occur in unstressed yeast cells, and, during stress, grow before the appearance of visible stress granules. Stress-induced transcripts are excluded from TIICs primarily due to the timing of their expression, rather than their sequence features. Together, our results reveal a simple system by which cells redirect translational activity to newly synthesized transcripts during stress, with broad implications for cellular regulation in changing conditions.
Collapse
Affiliation(s)
- Hendrik Glauninger
- Graduate Program in Biophysical Sciences, The University of Chicago, Chicago, IL, USA
- Interdisciplinary Scientist Training Program, The University of Chicago, Chicago, IL, USA
| | - Jared A.M. Bard
- Department of Biology, Texas A&M University, College Station, TX, USA
| | | | - Edo M. Airoldi
- Fox School of Business and Management, Temple University, Philadelphia, PA, USA
| | - Weihan Li
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Robert H. Singer
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY, USA
- Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY, USA
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Sneha Paul
- Department of Biochemistry & Molecular Biology, The University of Chicago, Chicago, IL, USA
| | - Jingyi Fei
- Department of Biochemistry & Molecular Biology, The University of Chicago, Chicago, IL, USA
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA
| | - Tobin R. Sosnick
- Department of Biochemistry & Molecular Biology, The University of Chicago, Chicago, IL, USA
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA
| | | | - D. Allan Drummond
- Department of Biochemistry & Molecular Biology, The University of Chicago, Chicago, IL, USA
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA
- Department of Medicine, Section of Genetic Medicine, The University of Chicago, Chicago, IL, USA
| |
Collapse
|
3
|
Desroches Altamirano C, Kang MK, Jordan MA, Borianne T, Dilmen I, Gnädig M, von Appen A, Honigmann A, Franzmann TM, Alberti S. eIF4F is a thermo-sensing regulatory node in the translational heat shock response. Mol Cell 2024; 84:1727-1741.e12. [PMID: 38547866 DOI: 10.1016/j.molcel.2024.02.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 12/18/2023] [Accepted: 02/29/2024] [Indexed: 05/05/2024]
Abstract
Heat-shocked cells prioritize the translation of heat shock (HS) mRNAs, but the underlying mechanism is unclear. We report that HS in budding yeast induces the disassembly of the eIF4F complex, where eIF4G and eIF4E assemble into translationally arrested mRNA ribonucleoprotein particles (mRNPs) and HS granules (HSGs), whereas eIF4A promotes HS translation. Using in vitro reconstitution biochemistry, we show that a conformational rearrangement of the thermo-sensing eIF4A-binding domain of eIF4G dissociates eIF4A and promotes the assembly with mRNA into HS-mRNPs, which recruit additional translation factors, including Pab1p and eIF4E, to form multi-component condensates. Using extracts and cellular experiments, we demonstrate that HS-mRNPs and condensates repress the translation of associated mRNA and deplete translation factors that are required for housekeeping translation, whereas HS mRNAs can be efficiently translated by eIF4A. We conclude that the eIF4F complex is a thermo-sensing node that regulates translation during HS.
Collapse
Affiliation(s)
- Christine Desroches Altamirano
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Moo-Koo Kang
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Mareike A Jordan
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, 01307 Dresden, Germany
| | - Tom Borianne
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Irem Dilmen
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Maren Gnädig
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Alexander von Appen
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, 01307 Dresden, Germany
| | - Alf Honigmann
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Titus M Franzmann
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Simon Alberti
- Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany.
| |
Collapse
|
4
|
Keyport Kik S, Christopher D, Glauninger H, Hickernell CW, Bard JAM, Lin KM, Squires AH, Ford M, Sosnick TR, Drummond DA. An adaptive biomolecular condensation response is conserved across environmentally divergent species. Nat Commun 2024; 15:3127. [PMID: 38605014 PMCID: PMC11009240 DOI: 10.1038/s41467-024-47355-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Accepted: 03/27/2024] [Indexed: 04/13/2024] Open
Abstract
Cells must sense and respond to sudden maladaptive environmental changes-stresses-to survive and thrive. Across eukaryotes, stresses such as heat shock trigger conserved responses: growth arrest, a specific transcriptional response, and biomolecular condensation of protein and mRNA into structures known as stress granules under severe stress. The composition, formation mechanism, adaptive significance, and even evolutionary conservation of these condensed structures remain enigmatic. Here we provide a remarkable view into stress-triggered condensation, its evolutionary conservation and tuning, and its integration into other well-studied aspects of the stress response. Using three morphologically near-identical budding yeast species adapted to different thermal environments and diverged by up to 100 million years, we show that proteome-scale biomolecular condensation is tuned to species-specific thermal niches, closely tracking corresponding growth and transcriptional responses. In each species, poly(A)-binding protein-a core marker of stress granules-condenses in isolation at species-specific temperatures, with conserved molecular features and conformational changes modulating condensation. From the ecological to the molecular scale, our results reveal previously unappreciated levels of evolutionary selection in the eukaryotic stress response, while establishing a rich, tractable system for further inquiry.
Collapse
Affiliation(s)
- Samantha Keyport Kik
- Committee on Genetics, Genomics, and Systems Biology, The University of Chicago, Chicago, IL, USA
| | - Dana Christopher
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
| | - Hendrik Glauninger
- Graduate Program in Biophysical Sciences, The University of Chicago, Chicago, IL, USA
- Interdisciplinary Scientist Training Program, The University of Chicago, Chicago, IL, USA
| | - Caitlin Wong Hickernell
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
| | - Jared A M Bard
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
| | - Kyle M Lin
- Graduate Program in Biophysical Sciences, The University of Chicago, Chicago, IL, USA
- Interdisciplinary Scientist Training Program, The University of Chicago, Chicago, IL, USA
| | - Allison H Squires
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA
| | | | - Tobin R Sosnick
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA
| | - D Allan Drummond
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, USA.
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, USA.
- Department of Medicine, Section of Genetic Medicine, The University of Chicago, Chicago, IL, USA.
| |
Collapse
|
5
|
Solari CA, Ortolá Martínez MC, Fernandez JM, Bates C, Cueto G, Valacco MP, Morales-Polanco F, Moreno S, Rossi S, Ashe MP, Portela P. Riboproteome remodeling during quiescence exit in Saccharomyces cerevisiae. iScience 2024; 27:108727. [PMID: 38235324 PMCID: PMC10792236 DOI: 10.1016/j.isci.2023.108727] [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: 02/02/2023] [Revised: 08/15/2023] [Accepted: 12/11/2023] [Indexed: 01/19/2024] Open
Abstract
The quiescent state is the prevalent mode of cellular life in most cells. Saccharomyces cerevisiae is a useful model for studying the molecular basis of the cell cycle, quiescence, and aging. Previous studies indicate that heterogeneous ribosomes show a specialized translation function to adjust the cellular proteome upon a specific stimulus. Using nano LC-MS/MS, we identified 69 of the 79 ribosomal proteins (RPs) that constitute the eukaryotic 80S ribosome during quiescence. Our study shows that the riboproteome is composed of 444 accessory proteins comprising cellular functions such as translation, protein folding, amino acid and glucose metabolism, cellular responses to oxidative stress, and protein degradation. Furthermore, the stoichiometry of both RPs and accessory proteins on ribosome particles is different depending on growth conditions and among monosome and polysome fractions. Deficiency of different RPs resulted in defects of translational capacity, suggesting that ribosome composition can result in changes in translational activity during quiescence.
Collapse
Affiliation(s)
- Clara A. Solari
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET), Buenos Aires, Argentina
| | - María Clara Ortolá Martínez
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET), Buenos Aires, Argentina
| | - Juan M. Fernandez
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET), Buenos Aires, Argentina
| | - Christian Bates
- The Michael Smith Building, Faculty of Life Sciences, University of Manchester, Manchester, UK
| | - Gerardo Cueto
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Ecología, Genética y Evolución, Instituto IEGEBA (CONICET-UBA), Buenos Aires, Argentina
| | - María Pía Valacco
- CEQUIBIEM- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET), Buenos Aires, Argentina
| | - Fabián Morales-Polanco
- The Michael Smith Building, Faculty of Life Sciences, University of Manchester, Manchester, UK
| | - Silvia Moreno
- CEQUIBIEM- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET), Buenos Aires, Argentina
| | - Silvia Rossi
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET), Buenos Aires, Argentina
| | - Mark P. Ashe
- The Michael Smith Building, Faculty of Life Sciences, University of Manchester, Manchester, UK
| | - Paula Portela
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET), Buenos Aires, Argentina
| |
Collapse
|
6
|
Roscoe S, Guo Y, Vacratsis PO, Ananvoranich S. Proteomic profile of Toxoplasma gondii stress granules by high-resolution mass spectrometry. Can J Microbiol 2024; 70:32-39. [PMID: 37826860 DOI: 10.1139/cjm-2023-0091] [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: 10/14/2023]
Abstract
Ribonucleoprotein granules are bio-condensates that form a diverse group of dynamic membrane-less organelles implicated in several cellular functions, including stress response and cellular survival. In Toxoplasma gondii, a type of bio-condensates referred to as stress granules (SGs) are formed prior to the parasites' egress from the host cell and are implicated in the survival and invasion competency of extracellular tachyzoites. We used paraformaldehyde to fix and cross-link SG proteins to allow purification by centrifugation and analysis by mass spectrometry. We profiled protein components of SGs at 10 and 30 min post-egress when parasite's invasion ability is significantly diminished. Thirty-three proteins were identified from 10 min SGs, and additional 43 proteins were identified from 30 min SGs. Notably, common SG components such as proteins with intrinsically disordered domains were not identified. Gene ontology analysis of both 10 and 30 min SGs shows that overall molecular functions of SGs' proteins are ATP-binding, GTP-binding, and GTPase activity. Discernable differences between 10 and 30 min SGs are in the proportions of translation and microtubule-related proteins. Ten-minute SGs have a higher proportion of microtubule-related proteins and a lower proportion of ribosome-related proteins, while a reverse correlation was identified for those of 30 min. It remains to be investigated whether this reverse correlation contributes to the ability of extracellular tachyzoites to reinvade host cells.
Collapse
Affiliation(s)
- Scott Roscoe
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON N9B3P4, Canada
| | - Yue Guo
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON N9B3P4, Canada
| | - Panayiotis O Vacratsis
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON N9B3P4, Canada
| | - Sirinart Ananvoranich
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON N9B3P4, Canada
| |
Collapse
|
7
|
Ando R, Ishikawa Y, Kamada Y, Izawa S. Contribution of the yeast bi-chaperone system in the restoration of the RNA helicase Ded1 and translational activity under severe ethanol stress. J Biol Chem 2023; 299:105472. [PMID: 37979914 PMCID: PMC10746526 DOI: 10.1016/j.jbc.2023.105472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 10/30/2023] [Accepted: 11/03/2023] [Indexed: 11/20/2023] Open
Abstract
Preexposure to mild stress often improves cellular tolerance to subsequent severe stress. Severe ethanol stress (10% v/v) causes persistent and pronounced translation repression in Saccharomyces cerevisiae. However, it remains unclear whether preexposure to mild stress can mitigate translation repression in yeast cells under severe ethanol stress. We found that the translational activity of yeast cells pretreated with 6% (v/v) ethanol was initially significantly repressed under subsequent 10% ethanol but was then gradually restored even under severe ethanol stress. We also found that 10% ethanol caused the aggregation of Ded1, which plays a key role in translation initiation as a DEAD-box RNA helicase. Pretreatment with 6% ethanol led to the gradual disaggregation of Ded1 under subsequent 10% ethanol treatment in wild-type cells but not in fes1Δhsp104Δ cells, which are deficient in Hsp104 with significantly reduced capacity for Hsp70. Hsp104 and Hsp70 are key components of the bi-chaperone system that play a role in yeast protein quality control. fes1Δhsp104Δ cells did not restore translational activity under 10% ethanol, even after pretreatment with 6% ethanol. These results indicate that the regeneration of Ded1 through the bi-chaperone system leads to the gradual restoration of translational activity under continuous severe stress. This study provides new insights into the acquired tolerance of yeast cells to severe ethanol stress and the resilience of their translational activity.
Collapse
Affiliation(s)
- Ryoko Ando
- Graduate School of Science and Technology, Kyoto Institute of Technology, Sakyo-ku, Kyoto, Japan
| | - Yu Ishikawa
- Graduate School of Science and Technology, Kyoto Institute of Technology, Sakyo-ku, Kyoto, Japan
| | | | - Shingo Izawa
- Graduate School of Science and Technology, Kyoto Institute of Technology, Sakyo-ku, Kyoto, Japan.
| |
Collapse
|
8
|
Grimes B, Jacob W, Liberman AR, Kim N, Zhao X, Masison DC, Greene LE. The Properties and Domain Requirements for Phase Separation of the Sup35 Prion Protein In Vivo. Biomolecules 2023; 13:1370. [PMID: 37759770 PMCID: PMC10526957 DOI: 10.3390/biom13091370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 09/05/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
The Sup35 prion protein of budding yeast has been reported to undergo phase separation to form liquid droplets both at low pH in vitro and when energy depletion decreases the intracellular pH in vivo. It also has been shown using purified proteins that this phase separation is driven by the prion domain of Sup35 and does not re-quire its C-terminal domain. In contrast, we now find that a Sup35 fragment consisting of only the N-terminal prion domain and the M-domain does not phase separate in vivo; this phase separation of Sup35 requires the C-terminal domain, which binds Sup45 to form the translation termination complex. The phase-separated Sup35 not only colocalizes with Sup45 but also with Pub1, a stress granule marker protein. In addition, like stress granules, phase separation of Sup35 appears to require mRNA since cycloheximide treatment, which inhibits mRNA release from ribosomes, prevents phase separation of Sup35. Finally, unlike Sup35 in vitro, Sup35 condensates do not disassemble in vivo when the intracellular pH is increased. These results suggest that, in energy-depleted cells, Sup35 forms supramolecular assemblies that differ from the Sup35 liquid droplets that form in vitro.
Collapse
Affiliation(s)
- Bryan Grimes
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Walter Jacob
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Amanda R. Liberman
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nathan Kim
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Xiaohong Zhao
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Daniel C. Masison
- Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lois E. Greene
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| |
Collapse
|
9
|
Kik SK, Christopher D, Glauninger H, Hickernell CW, Bard JAM, Ford M, Sosnick TR, Drummond DA. An adaptive biomolecular condensation response is conserved across environmentally divergent species. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.28.551061. [PMID: 37546789 PMCID: PMC10402146 DOI: 10.1101/2023.07.28.551061] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Cells must sense and respond to sudden maladaptive environmental changes-stresses-to survive and thrive. Across eukaryotes, stresses such as heat shock trigger conserved responses: growth arrest, a specific transcriptional response, and biomolecular condensation of protein and mRNA into structures known as stress granules under severe stress. The composition, formation mechanism, adaptive significance, and even evolutionary conservation of these condensed structures remain enigmatic. Here we provide an unprecedented view into stress-triggered condensation, its evolutionary conservation and tuning, and its integration into other well-studied aspects of the stress response. Using three morphologically near-identical budding yeast species adapted to different thermal environments and diverged by up to 100 million years, we show that proteome-scale biomolecular condensation is tuned to species-specific thermal niches, closely tracking corresponding growth and transcriptional responses. In each species, poly(A)-binding protein-a core marker of stress granules-condenses in isolation at species-specific temperatures, with conserved molecular features and conformational changes modulating condensation. From the ecological to the molecular scale, our results reveal previously unappreciated levels of evolutionary selection in the eukaryotic stress response, while establishing a rich, tractable system for further inquiry.
Collapse
Affiliation(s)
- Samantha Keyport Kik
- Committee on Genetics, Genomics, and Systems Biology, The University of Chicago, Chicago, IL
| | - Dana Christopher
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL
| | - Hendrik Glauninger
- Graduate Program in Biophysical Sciences, The University of Chicago, Chicago, IL
| | | | - Jared A. M. Bard
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL
| | | | - Tobin R. Sosnick
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL
- Graduate Program in Biophysical Sciences, The University of Chicago, Chicago, IL
| | - D. Allan Drummond
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL
- Department of Medicine, Section of Genetic Medicine, The University of Chicago, Chicago, IL
| |
Collapse
|
10
|
Layana C, Vilardo ES, Corujo G, Hernández G, Rivera-Pomar R. Drosophila Me31B is a Dual eIF4E-Interacting Protein. J Mol Biol 2023; 435:167949. [PMID: 36638908 DOI: 10.1016/j.jmb.2023.167949] [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: 11/12/2021] [Revised: 12/14/2022] [Accepted: 01/03/2023] [Indexed: 01/12/2023]
Abstract
Eukaryotic translation initiation factor 4E (eIF4E) is a key factor involved in different aspects of mRNA metabolism. Drosophila melanogaster genome encodes eight eIF4E isoforms, and the canonical isoform eIF4E-1 is a ubiquitous protein that plays a key role in mRNA translation. eIF4E-3 is specifically expressed in testis and controls translation during spermatogenesis. In eukaryotic cells, translational control and mRNA decay is highly regulated in different cytoplasmic ribonucleoprotein foci, which include the processing bodies (PBs). In this study, we show that Drosophila eIF4E-1 and eIF4E-3 occur in PBs along the DEAD-box RNA helicase Me31B. We show that Me31B interacts with eIF4E-1 and eIF4E-3 by means of yeast two-hybrid system, FRET in D. melanogaster S2 cells and coimmunoprecipitation in testis. Truncation and point mutations of Me31B proteins show two eIF4E-binding sites located in different protein domains. Residues Y401-L407 (at the carboxy-terminus) are essential for interaction with eIF4E-1, whereas residues F63-L70 (at the amino-terminus) are critical for interaction with eIF4E-3. The residue W117 in eIF4E-1 and the homolog position F103 in eIF4E-3 are necessary for Me31B-eIF4E interaction suggesting that the change of tryptophan to phenylalanine provides specificity. Me31B represents a novel type of eIF4E-interacting protein with dual and specific interaction domains that might be recognized by different eIF4E isoforms in different tissues, adding complexity to the control of gene expression in eukaryotes.
Collapse
Affiliation(s)
- Carla Layana
- Centro Regional de Estudios Genómicos, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Boulevard 120 N° 1459, 1900 La Plata, Argentina.
| | - Emiliano Salvador Vilardo
- Centro Regional de Estudios Genómicos, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Boulevard 120 N° 1459, 1900 La Plata, Argentina
| | - Gonzalo Corujo
- Centro Regional de Estudios Genómicos, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Boulevard 120 N° 1459, 1900 La Plata, Argentina
| | - Greco Hernández
- Translation and Cancer Laboratory, Unit of Biomedical Research on Cancer, National Institute of Cancer (Instituto Nacional de Cancerología, INCan), 22 San Fernando Ave., Tlalpan, 14080 Mexico City, Mexico
| | - Rolando Rivera-Pomar
- Centro Regional de Estudios Genómicos, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Boulevard 120 N° 1459, 1900 La Plata, Argentina; Centro de Investigación y Transferencia del Noroeste de Buenos Aires (CITNOBA) - Centro de Bioinvestigaciones, Universidad Nacional del Noroeste de Buenos Aires, Av. Presidente Frondizi Km 4, 2700 Pergamino, Argentina; Molecular Developmental Biology Emeritus Group, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077 Göttingen, Germany
| |
Collapse
|
11
|
Makeeva DS, Riggs CL, Burakov AV, Ivanov PA, Kushchenko AS, Bykov DA, Popenko VI, Prassolov VS, Ivanov PV, Dmitriev SE. Relocalization of Translation Termination and Ribosome Recycling Factors to Stress Granules Coincides with Elevated Stop-Codon Readthrough and Reinitiation Rates upon Oxidative Stress. Cells 2023; 12:259. [PMID: 36672194 PMCID: PMC9856671 DOI: 10.3390/cells12020259] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 12/27/2022] [Accepted: 01/03/2023] [Indexed: 01/11/2023] Open
Abstract
Upon oxidative stress, mammalian cells rapidly reprogram their translation. This is accompanied by the formation of stress granules (SGs), cytoplasmic ribonucleoprotein condensates containing untranslated mRNA molecules, RNA-binding proteins, 40S ribosomal subunits, and a set of translation initiation factors. Here we show that arsenite-induced stress causes a dramatic increase in the stop-codon readthrough rate and significantly elevates translation reinitiation levels on uORF-containing and bicistronic mRNAs. We also report the recruitment of translation termination factors eRF1 and eRF3, as well as ribosome recycling and translation reinitiation factors ABCE1, eIF2D, MCT-1, and DENR to SGs upon arsenite treatment. Localization of these factors to SGs may contribute to a rapid resumption of mRNA translation after stress relief and SG disassembly. It may also suggest the presence of post-termination, recycling, or reinitiation complexes in SGs. This new layer of translational control under stress conditions, relying on the altered spatial distribution of translation factors between cellular compartments, is discussed.
Collapse
Affiliation(s)
- Desislava S. Makeeva
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Claire L. Riggs
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Anton V. Burakov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Pavel A. Ivanov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Artem S. Kushchenko
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, 119234 Moscow, Russia
| | - Dmitri A. Bykov
- Faculty of Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Vladimir I. Popenko
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Vladimir S. Prassolov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| | - Pavel V. Ivanov
- Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Sergey E. Dmitriev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119234 Moscow, Russia
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, 119234 Moscow, Russia
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 119991 Moscow, Russia
| |
Collapse
|
12
|
Sivananthan S, Gosse JT, Huard S, Baetz K. Pab1 acetylation at K131 decreases stress granule formation in Saccharomyces cerevisiae. J Biol Chem 2022; 299:102834. [PMID: 36572187 PMCID: PMC9867979 DOI: 10.1016/j.jbc.2022.102834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 12/25/2022] Open
Abstract
Under environmental stress, such as glucose deprivation, cells form stress granules-the accumulation of cytoplasmic aggregates of repressed translational initiation complexes, proteins, and stalled mRNAs. Recent research implicates stress granules in various diseases, such as neurodegenerative diseases, but the exact regulators responsible for the assembly and disassembly of stress granules are unknown. An important aspect of stress granule formation is the presence of posttranslational modifications on core proteins. One of those modifications is lysine acetylation, which is regulated by either a lysine acetyltransferase or a lysine deacetylase enzyme. This work deciphers the impact of lysine acetylation on an essential protein found in Saccharomyces cerevisiae stress granules, poly(A)-binding protein (Pab1). We demonstrated that an acetylation mimic of the lysine residue in position 131 reduces stress granule formation upon glucose deprivation and other stressors such as ethanol, raffinose, and vanillin. We present genetic evidence that the enzyme Rpd3 is the primary candidate for the deacetylation of Pab1-K131. Further, our electromobility shift assay studies suggest that the acetylation of Pab1-K131 negatively impacts poly(A) RNA binding. Due to the conserved nature of stress granules, therapeutics targeting the activity of lysine acetyltransferases and lysine deacetylase enzymes may be a promising route to modulate stress granule dynamics in the disease state.
Collapse
Affiliation(s)
- Sangavi Sivananthan
- Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Jessica T. Gosse
- Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Sylvain Huard
- Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Kristin Baetz
- Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada; Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada.
| |
Collapse
|
13
|
Dhaliwal JS, Panozzo C, Benard L, Zerges W. An RNA granule for translation quality control in Saccharomyces cerevisiae. J Cell Sci 2022; 135:285862. [PMID: 36373798 DOI: 10.1242/jcs.260388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 10/31/2022] [Indexed: 11/16/2022] Open
Abstract
Cytoplasmic RNA granules compartmentalize phases of the translation cycle in eukaryotes. We previously reported the localization of oxidized RNA to cytoplasmic foci called oxidized RNA bodies (ORBs) in human cells. We show here that ORBs are RNA granules in Saccharomyces cerevisiae. Several lines of evidence support a role for ORBs in the compartmentalization of no-go decay and ribosome quality control, the translation quality control pathways that recognize and clear aberrant mRNAs, including those with oxidized bases. Translation is required by these pathways and ORBs. Translation quality control factors localize to ORBs. A substrate of translation quality control, a stalled mRNA-ribosome-nascent-chain complex, localizes to ORBs. Translation quality control mutants have altered ORB numbers, sizes or both. In addition, we identify 68 ORB proteins by immunofluorescence staining directed by proteomics, which further support their role in translation quality control and reveal candidate new factors for these pathways.
Collapse
Affiliation(s)
- James S Dhaliwal
- Department of Biology, Concordia University, 7141 Sherbrooke W, Montreal, Quebec, Canada, H4B 1R6
| | - Cristina Panozzo
- Institut de Biologie Physico-Chimique, UMR8226, CNRS, Sorbonne Université, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - Lionel Benard
- Institut de Biologie Physico-Chimique, UMR8226, CNRS, Sorbonne Université, 13 rue Pierre et Marie Curie, 75005, Paris, France
| | - William Zerges
- Department of Biology, Concordia University, 7141 Sherbrooke W, Montreal, Quebec, Canada, H4B 1R6
| |
Collapse
|
14
|
Chaves-Arquero B, Martínez-Lumbreras S, Sibille N, Camero S, Bernadó P, Jiménez MÁ, Zorrilla S, Pérez-Cañadillas JM. eIF4G1 N-terminal intrinsically disordered domain is a multi-docking station for RNA, Pab1, Pub1, and self-assembly. Front Mol Biosci 2022; 9:986121. [PMID: 36213119 PMCID: PMC9537944 DOI: 10.3389/fmolb.2022.986121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
Yeast eIF4G1 interacts with RNA binding proteins (RBPs) like Pab1 and Pub1 affecting its function in translation initiation and stress granules formation. We present an NMR and SAXS study of the N-terminal intrinsically disordered region of eIF4G1 (residues 1-249) and its interactions with Pub1, Pab1 and RNA. The conformational ensemble of eIF4G11-249 shows an α-helix within the BOX3 conserved element and a dynamic network of fuzzy π-π and π-cation interactions involving arginine and aromatic residues. The Pab1 RRM2 domain interacts with eIF4G1 BOX3, the canonical interaction site, but also with BOX2, a conserved element of unknown function to date. The RNA1 region interacts with RNA through a new RNA interaction motif and with the Pub1 RRM3 domain. This later also interacts with eIF4G1 BOX1 modulating its intrinsic self-assembly properties. The description of the biomolecular interactions involving eIF4G1 to the residue detail increases our knowledge about biological processes involving this key translation initiation factor.
Collapse
Affiliation(s)
- Belén Chaves-Arquero
- Department of Biological Physical Chemistry, Institute of Physical-Chemistry “Rocasolano”, CSIC, Madrid, Spain
| | - Santiago Martínez-Lumbreras
- Department of Biological Physical Chemistry, Institute of Physical-Chemistry “Rocasolano”, CSIC, Madrid, Spain
| | - Nathalie Sibille
- Centre de Biochimie Structurale (CBS), CNRS, INSERM, Univ. Montpellier, Montpellier, France
| | - Sergio Camero
- Department of Biological Physical Chemistry, Institute of Physical-Chemistry “Rocasolano”, CSIC, Madrid, Spain
| | - Pau Bernadó
- Centre de Biochimie Structurale (CBS), CNRS, INSERM, Univ. Montpellier, Montpellier, France
| | - M. Ángeles Jiménez
- Department of Biological Physical Chemistry, Institute of Physical-Chemistry “Rocasolano”, CSIC, Madrid, Spain
| | - Silvia Zorrilla
- Department of Cellular and Molecular Biology, Biological Research Center, CSIC, Madrid, Spain
| | | |
Collapse
|
15
|
Roy R, Das G, Kuttanda IA, Bhatter N, Rajyaguru PI. Low complexity RGG-motif sequence is required for Processing body (P-body) disassembly. Nat Commun 2022; 13:2077. [PMID: 35440550 PMCID: PMC9019020 DOI: 10.1038/s41467-022-29715-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 03/21/2022] [Indexed: 01/12/2023] Open
Abstract
P-bodies are conserved mRNP complexes that are implicated in determining mRNA fate by affecting translation and mRNA decay. In this report, we identify RGG-motif containing translation repressor protein Sbp1 as a disassembly factor of P-bodies since disassembly of P-bodies is defective in Δsbp1. RGG-motif is necessary and sufficient to rescue the PB disassembly defect in Δsbp1. Binding studies using purified proteins revealed that Sbp1 physically interacts with Edc3 and Sbp1-Edc3 interaction competes with Edc3-Edc3 interaction. Purified Edc3 forms assemblies, promoted by the presence of RNA and NADH and the addition of purified Sbp1, but not the RGG-deletion mutant, leads to significantly decreased Edc3 assemblies. We further note that the aggregates of human EWSR1 protein, implicated in neurodegeneration, are more persistent in the absence of Sbp1 and overexpression of EWSR1 in Δsbp1 leads to a growth defect. Taken together, our observations suggest a role of Sbp1 in disassembly, which could apply to disease-relevant heterologous protein-aggregates.
Collapse
Affiliation(s)
- Raju Roy
- Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Gitartha Das
- Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India
| | | | - Nupur Bhatter
- Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India
| | | |
Collapse
|
16
|
Takaine M, Imamura H, Yoshida S. High and stable ATP levels prevent aberrant intracellular protein aggregation in yeast. eLife 2022; 11:67659. [PMID: 35438635 PMCID: PMC9018071 DOI: 10.7554/elife.67659] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 03/18/2022] [Indexed: 12/24/2022] Open
Abstract
Adenosine triphosphate (ATP) at millimolar levels has recently been implicated in the solubilization of cellular proteins. However, the significance of this high ATP level under physiological conditions and the mechanisms that maintain ATP remain unclear. We herein demonstrated that AMP-activated protein kinase (AMPK) and adenylate kinase (ADK) cooperated to maintain cellular ATP levels regardless of glucose levels. Single-cell imaging of ATP-reduced yeast mutants revealed that ATP levels in these mutants underwent stochastic and transient depletion, which promoted the cytotoxic aggregation of endogenous proteins and pathogenic proteins, such as huntingtin and α-synuclein. Moreover, pharmacological elevations in ATP levels in an ATP-reduced mutant prevented the accumulation of α-synuclein aggregates and its cytotoxicity. The present study demonstrates that cellular ATP homeostasis ensures proteostasis and revealed that suppressing the high volatility of cellular ATP levels prevented cytotoxic protein aggregation, implying that AMPK and ADK are important factors that prevent proteinopathies, such as neurodegenerative diseases. Cells use a chemical called adenosine triphosphate (ATP) as a controllable source of energy. Like a battery, each ATP molecule contains a specific amount of energy that can be released when needed. Cells just need enough ATP to survive, but most cells store a lot more than they need. It is unclear why cells keep so much ATP, or whether this excess ATP has any other purpose. To answer these questions, Takaine et al. identified mutants of the yeast Saccharomyces cerevisiae that had low levels of ATP, and studied how these cells differ from normal yeast The results showed that, in S. cerevisiae cells with lower and variable levels of ATP, proteins stick together, forming clumps. Proteins are molecules that perform diverse roles, keeping cells alive. When they clump together, they stop working and can cause cells to die. Further experiments showed that reducing the levels of ATP just for a short time increased the rate at which proteins stick together. Taken together, Takaine et al.’s results suggest that ATP plays a role in stopping proteins from sticking together, explaining why cells may store excess ATP, since it could aid survival. Protein clumps, also called aggregates, are a key feature of various illnesses, including neurodegenerative diseases such as Alzheimer’s. Takaine et al. provide a possible cause for why proteins aggregate in these diseases, which may be worth further study.
Collapse
Affiliation(s)
- Masak Takaine
- Gunma University Initiative for Advanced Research (GIAR), Gunma University, Maebashi, Japan.,Institute for Molecular and Cellular Regulation (IMCR), Gunma University, Maebashi, Japan
| | - Hiromi Imamura
- Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Satoshi Yoshida
- Gunma University Initiative for Advanced Research (GIAR), Gunma University, Maebashi, Japan.,Institute for Molecular and Cellular Regulation (IMCR), Gunma University, Maebashi, Japan.,School of International Liberal Studies, Waseda University, Tokyo, Japan.,Japan Science and Technology Agency, PREST, Tokyo, Japan
| |
Collapse
|
17
|
Lachke SA. RNA-binding proteins and post-transcriptional regulation in lens biology and cataract: Mediating spatiotemporal expression of key factors that control the cell cycle, transcription, cytoskeleton and transparency. Exp Eye Res 2022; 214:108889. [PMID: 34906599 PMCID: PMC8792301 DOI: 10.1016/j.exer.2021.108889] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 11/29/2021] [Accepted: 12/05/2021] [Indexed: 01/03/2023]
Abstract
Development of the ocular lens - a transparent tissue capable of sustaining frequent shape changes for optimal focusing power - pushes the boundaries of what cells can achieve using the molecular toolkit encoded by their genomes. The mammalian lens contains broadly two types of cells, the anteriorly located monolayer of epithelial cells which, at the equatorial region of the lens, initiate differentiation into fiber cells that contribute to the bulk of the tissue. This differentiation program involves massive upregulation of select fiber cell-expressed RNAs and their subsequent translation into high amounts of proteins, such as crystallins. But intriguingly, fiber cells achieve this while also simultaneously undergoing significant morphological changes such as elongation - involving about 1000-fold length-wise increase - and migration, which requires modulation of cytoskeletal and cell adhesion factors. Adding further to the challenges, these molecular and cellular events have to be coordinated as fiber cells progress toward loss of their nuclei and organelles, which irreversibly compromises their potential for harnessing genetically hardwired information. A long-standing question is how processes downstream of signaling and transcription, which may also participate in feedback regulation, contribute toward orchestrating these cellular differentiation events in the lens. It is now becoming clear from findings over the past decade that post-transcriptional gene expression regulatory mechanisms are critical in controlling cellular proteomes and coordinating key processes in lens development and fiber cell differentiation. Indeed, RNA-binding proteins (RBPs) such as Caprin2, Celf1, Rbm24 and Tdrd7 have now been described in mediating post-transcriptional control over key factors (e.g. Actn2, Cdkn1a (p21Cip1), Cdkn1b (p27Kip1), various crystallins, Dnase2b, Hspb1, Pax6, Prox1, Sox2) that are variously involved in cell cycle, transcription, cytoskeleton maintenance and differentiation in the lens. Furthermore, deficiencies of these RBPs have been shown to result in various eye and lens defects and/or cataract. Because fiber cell differentiation in the lens occurs throughout life, the underlying regulatory mechanisms operational in development are expected to also be recruited for the maintenance of transparency in aged lenses. Indeed, in support of this, TDRD7 and CAPRIN2 loci have been linked to age-related cataract in humans. Here, I will review the role of key RBPs in the lens and their importance in understanding the pathology of lens defects. I will discuss advances in RBP-based gene expression control, in general, and the important challenges that need to be addressed in the lens to define the mechanisms that determine the epithelial and fiber cell proteome. Finally, I will also discuss in detail several key future directions including the application of bioinformatics approaches such as iSyTE to study RBP-based post-transcriptional gene expression control in the aging lens and in the context of age-related cataract.
Collapse
Affiliation(s)
- Salil A Lachke
- Department of Biological Sciences, University of Delaware, 105 The Green, Delaware Avenue, 236 Wolf Hall, Newark, DE, USA; Center for Bioinformatics & Computational Biology, University of Delaware, Newark, DE, 19716, USA.
| |
Collapse
|
18
|
Grousl T, Vojtova J, Hasek J, Vomastek T. Yeast stress granules at a glance. Yeast 2021; 39:247-261. [PMID: 34791685 DOI: 10.1002/yea.3681] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 10/15/2021] [Accepted: 11/12/2021] [Indexed: 11/10/2022] Open
Abstract
The formation of stress granules (SGs), membrane-less organelles that are composed of mainly messenger ribonucleoprotein assemblies, is the result of a conserved evolutionary strategy to cellular stress. During their formation, which is triggered by robust environmental stress, SGs sequester translationally inactive mRNA molecules, which are either forwarded for further processing elsewhere or stored during a period of stress within SGs. Removal of mRNA molecules from active translation and their sequestration in SGs allows preferential translation of stress response transcripts. By affecting the specificity of mRNA translation, mRNA localization and stability, SGs are involved in the overall cellular reprogramming during periods of environmental stress and viral infection. Over the past two decades, we have learned which processes drive SGs assembly, how their composition varies under stress, and how they co-exist with other subcellular organelles. Yeast as a model has been instrumental in our understanding of SG biology. Despite the specific differences between the SGs of yeast and mammals, yeast have been shown to be a valuable tool to the study of SGs in translation-related stress response. This review summarizes the data surrounding SGs that are formed under different stress conditions in Saccharomyces cerevisiae and other yeast species. It offers a comprehensive and up-to-date view on these still somewhat mysterious entities.
Collapse
Affiliation(s)
- Tomas Grousl
- Laboratory of Cell Signalling, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jana Vojtova
- Laboratory of Cell Reproduction, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jiri Hasek
- Laboratory of Cell Reproduction, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Tomas Vomastek
- Laboratory of Cell Signalling, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| |
Collapse
|
19
|
Kershaw CJ, Nelson MG, Lui J, Bates CP, Jennings MD, Hubbard SJ, Ashe MP, Grant CM. Integrated multi-omics reveals common properties underlying stress granule and P-body formation. RNA Biol 2021; 18:655-673. [PMID: 34672913 PMCID: PMC8782181 DOI: 10.1080/15476286.2021.1976986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Non-membrane-bound compartments such as P-bodies (PBs) and stress granules (SGs) play important roles in the regulation of gene expression following environmental stresses. We have systematically and quantitatively determined the protein and mRNA composition of PBs and SGs formed before and after nutrient stress. We find that high molecular weight (HMW) complexes exist prior to glucose depletion that we propose may act as seeds for further condensation of proteins forming mature PBs and SGs. We identify an enrichment of proteins with low complexity and RNA binding domains, as well as long, structured mRNAs that are poorly translated following nutrient stress. Many proteins and mRNAs are shared between PBs and SGs including several multivalent RNA binding proteins that promote condensate interactions during liquid-liquid phase separation. We uncover numerous common protein and RNA components across PBs and SGs that support a complex interaction profile during the maturation of these biological condensates. These interaction networks represent a tuneable response to stress, highlighting previously unrecognized condensate heterogeneity. These studies therefore provide an integrated and quantitative understanding of the dynamic nature of key biological condensates.
Collapse
Affiliation(s)
- Christopher J Kershaw
- University of Manchester School of Biological Science, The University of Manchester Faculty of Biology Medicine and Health, Manchester, UK
| | - Michael G Nelson
- University of Manchester School of Biological Science, The University of Manchester Faculty of Biology Medicine and Health, Manchester, UK
| | - Jennifer Lui
- University of Manchester School of Biological Science, The University of Manchester Faculty of Biology Medicine and Health, Manchester, UK
| | - Christian P Bates
- University of Manchester School of Biological Science, The University of Manchester Faculty of Biology Medicine and Health, Manchester, UK
| | - Martin D Jennings
- University of Manchester School of Biological Science, The University of Manchester Faculty of Biology Medicine and Health, Manchester, UK
| | - Simon J Hubbard
- University of Manchester School of Biological Science, The University of Manchester Faculty of Biology Medicine and Health, Manchester, UK
| | - Mark P Ashe
- University of Manchester School of Biological Science, The University of Manchester Faculty of Biology Medicine and Health, Manchester, UK
| | - Chris M Grant
- University of Manchester School of Biological Science, The University of Manchester Faculty of Biology Medicine and Health, Manchester, UK
| |
Collapse
|
20
|
The multiscale and multiphase organization of the transcriptome. Emerg Top Life Sci 2021; 4:265-280. [PMID: 32542380 DOI: 10.1042/etls20190187] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/08/2020] [Accepted: 05/18/2020] [Indexed: 02/06/2023]
Abstract
Gene expression must be co-ordinated to cellular activity. From transcription to decay, the expression of millions of RNA molecules is highly synchronized. RNAs are covered by proteins that regulate every aspect of their cellular life: expression, storage, translational status, localization, and decay. Many RNAs and their associated regulatory proteins can coassemble to condense into liquid droplets, viscoelastic hydrogels, freeze into disorganized glass-like aggregates, or harden into quasi-crystalline solids. Phase separations provide a framework for transcriptome organization where the single functional unit is no longer a transcript but instead an RNA regulon. Here, we will analyze the interaction networks that underlie RNA super-assemblies, assess the complex multiscale, multiphase architecture of the transcriptome, and explore how the biophysical state of an RNA molecule can define its fate. Phase separations are emerging as critical routes for the epitranscriptomic control of gene expression.
Collapse
|
21
|
Maruri-López I, Figueroa NE, Hernández-Sánchez IE, Chodasiewicz M. Plant Stress Granules: Trends and Beyond. FRONTIERS IN PLANT SCIENCE 2021; 12:722643. [PMID: 34434210 PMCID: PMC8381727 DOI: 10.3389/fpls.2021.722643] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 07/01/2021] [Indexed: 05/20/2023]
Abstract
Stress granules (SGs) are dynamic membrane-less condensates transiently assembled through liquid-liquid phase separation (LLPS) in response to stress. SGs display a biphasic architecture constituted of core and shell phases. The core is a conserved SG fraction fundamental for its assembly and consists primarily of proteins with intrinsically disordered regions and RNA-binding domains, along with translational-related proteins. The shell fraction contains specific SG components that differ among species, cell type, and developmental stage and might include metabolic enzymes, receptors, transcription factors, untranslated mRNAs, and small molecules. SGs assembly positively correlates with stalled translation associated with stress responses playing a pivotal role during the adaptive cellular response, post-stress recovery, signaling, and metabolic rewire. After stress, SG disassembly releases mRNA and proteins to the cytoplasm to reactivate translation and reassume cell growth and development. However, under severe stress conditions or aberrant cellular behavior, SG dynamics are severely disturbed, affecting cellular homeostasis and leading to cell death in the most critical cases. The majority of research on SGs has focused on yeast and mammals as model organism. Nevertheless, the study of plant SGs has attracted attention in the last few years. Genetics studies and adapted techniques from other non-plant models, such as affinity capture coupled with multi-omics analyses, have enriched our understanding of SG composition in plants. Despite these efforts, the investigation of plant SGs is still an emerging field in plant biology research. In this review, we compile and discuss the accumulated progress of plant SGs regarding their composition, organization, dynamics, regulation, and their relation to other cytoplasmic foci. Lastly, we will explore the possible connections among the most exciting findings of SGs from mammalian, yeast, and plants, which might help provide a complete view of the biology of plant SGs in the future.
Collapse
Affiliation(s)
| | | | | | - Monika Chodasiewicz
- Biological and Environmental Science and Engineering Division, Center for Desert Agriculture, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| |
Collapse
|
22
|
Sprunger ML, Jackrel ME. Prion-Like Proteins in Phase Separation and Their Link to Disease. Biomolecules 2021; 11:biom11071014. [PMID: 34356638 PMCID: PMC8301953 DOI: 10.3390/biom11071014] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 06/28/2021] [Accepted: 07/06/2021] [Indexed: 02/01/2023] Open
Abstract
Aberrant protein folding underpins many neurodegenerative diseases as well as certain myopathies and cancers. Protein misfolding can be driven by the presence of distinctive prion and prion-like regions within certain proteins. These prion and prion-like regions have also been found to drive liquid-liquid phase separation. Liquid-liquid phase separation is thought to be an important physiological process, but one that is prone to malfunction. Thus, aberrant liquid-to-solid phase transitions may drive protein aggregation and fibrillization, which could give rise to pathological inclusions. Here, we review prions and prion-like proteins, their roles in phase separation and disease, as well as potential therapeutic approaches to counter aberrant phase transitions.
Collapse
|
23
|
Wang L, Yang W, Li B, Yuan S, Wang F. Response to stress in biological disorders: Implications of stress granule assembly and function. Cell Prolif 2021; 54:e13086. [PMID: 34170048 PMCID: PMC8349659 DOI: 10.1111/cpr.13086] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 06/06/2021] [Accepted: 06/07/2021] [Indexed: 12/17/2022] Open
Abstract
It is indispensable for cells to adapt and respond to environmental stresses, in order for organisms to survive. Stress granules (SGs) are condensed membrane‐less organelles dynamically formed in the cytoplasm of eukaryotes cells to cope with diverse intracellular or extracellular stress factors, with features of liquid‐liquid phase separation. They are composed of multiple constituents, including translationally stalled mRNAs, translation initiation factors, RNA‐binding proteins and also non‐RNA‐binding proteins. SG formation is triggered by stress stimuli, viral infection and signal transduction, while aberrant assembly of SGs may contribute to tissue degenerative diseases. Recently, a growing body of evidence has emerged on SG response mechanisms for cells facing high temperatures, oxidative stress and osmotic stress. In this review, we aim to summarize factors affecting SGs assembly, present the impact of SGs on germ cell development and other biological processes. We particularly emphasize the significance of recently reported RNA modifications in SG stress responses. In parallel, we also review all current perspectives on the roles of SGs in male germ cells, with a particular focus on the dynamics of SG assembly.
Collapse
Affiliation(s)
- Lingjuan Wang
- Institute Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Hubei, China
| | - Weina Yang
- Institute Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Hubei, China
| | - Bin Li
- Tianjin Medical University General Hospital, Tianjin, China.,State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
| | - Shuiqiao Yuan
- Institute Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Hubei, China
| | - Fengli Wang
- Institute Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Hubei, China
| |
Collapse
|
24
|
Arabidopsis thaliana G3BP Ortholog Rescues Mammalian Stress Granule Phenotype across Kingdoms. Int J Mol Sci 2021; 22:ijms22126287. [PMID: 34208100 PMCID: PMC8230867 DOI: 10.3390/ijms22126287] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 06/08/2021] [Accepted: 06/08/2021] [Indexed: 11/16/2022] Open
Abstract
Stress granules (SGs) are dynamic RNA–protein complexes localized in the cytoplasm that rapidly form under stress conditions and disperse when normal conditions are restored. The formation of SGs depends on the Ras-GAP SH3 domain-binding protein (G3BP). Formations, interactions and functions of plant and human SGs are strikingly similar, suggesting a conserved mechanism. However, functional analyses of plant G3BPs are missing. Thus, members of the Arabidopsis thaliana G3BP (AtG3BP) protein family were investigated in a complementation assay in a human G3BP knock-out cell line. It was shown that two out of seven AtG3BPs were able to complement the function of their human homolog. GFP-AtG3BP fusion proteins co-localized with human SG marker proteins Caprin-1 and eIF4G1 and restored SG formation in G3BP double KO cells. Interaction between AtG3BP-1 and -7 and known human G3BP interaction partners such as Caprin-1 and USP10 was also demonstrated by co-immunoprecipitation. In addition, an RG/RGG domain exchange from Arabidopsis G3BP into the human G3BP background showed the ability for complementation. In summary, our results support a conserved mechanism of SG function over the kingdoms, which will help to further elucidate the biological function of the Arabidopsis G3BP protein family.
Collapse
|
25
|
Marcelo A, Koppenol R, de Almeida LP, Matos CA, Nóbrega C. Stress granules, RNA-binding proteins and polyglutamine diseases: too much aggregation? Cell Death Dis 2021; 12:592. [PMID: 34103467 PMCID: PMC8187637 DOI: 10.1038/s41419-021-03873-8] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 05/25/2021] [Accepted: 05/25/2021] [Indexed: 02/05/2023]
Abstract
Stress granules (SGs) are membraneless cell compartments formed in response to different stress stimuli, wherein translation factors, mRNAs, RNA-binding proteins (RBPs) and other proteins coalesce together. SGs assembly is crucial for cell survival, since SGs are implicated in the regulation of translation, mRNA storage and stabilization and cell signalling, during stress. One defining feature of SGs is their dynamism, as they are quickly assembled upon stress and then rapidly dispersed after the stress source is no longer present. Recently, SGs dynamics, their components and their functions have begun to be studied in the context of human diseases. Interestingly, the regulated protein self-assembly that mediates SG formation contrasts with the pathological protein aggregation that is a feature of several neurodegenerative diseases. In particular, aberrant protein coalescence is a key feature of polyglutamine (PolyQ) diseases, a group of nine disorders that are caused by an abnormal expansion of PolyQ tract-bearing proteins, which increases the propensity of those proteins to aggregate. Available data concerning the abnormal properties of the mutant PolyQ disease-causing proteins and their involvement in stress response dysregulation strongly suggests an important role for SGs in the pathogenesis of PolyQ disorders. This review aims at discussing the evidence supporting the existence of a link between SGs functionality and PolyQ disorders, by focusing on the biology of SGs and on the way it can be altered in a PolyQ disease context.
Collapse
Affiliation(s)
- Adriana Marcelo
- Algarve Biomedical Center Research Institute (ABC-RI), Faro, Portugal
- PhD Program in Biomedial Sciences, Faculty of Medicine and Biomedical Sciences, University of Algarve, Faro, Portugal
- Centre for Biomedical Research (CBMR), Universidade do Algarve, Faro, Portugal
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
- Faculty of Medicine and Biomedical Sciences, University of Algarve, Faro, Portugal
| | - Rebekah Koppenol
- Algarve Biomedical Center Research Institute (ABC-RI), Faro, Portugal
- PhD Program in Biomedial Sciences, Faculty of Medicine and Biomedical Sciences, University of Algarve, Faro, Portugal
- Centre for Biomedical Research (CBMR), Universidade do Algarve, Faro, Portugal
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
- Faculty of Medicine and Biomedical Sciences, University of Algarve, Faro, Portugal
| | - Luís Pereira de Almeida
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - Carlos A Matos
- Algarve Biomedical Center Research Institute (ABC-RI), Faro, Portugal
- Centre for Biomedical Research (CBMR), Universidade do Algarve, Faro, Portugal
- Faculty of Medicine and Biomedical Sciences, University of Algarve, Faro, Portugal
| | - Clévio Nóbrega
- Algarve Biomedical Center Research Institute (ABC-RI), Faro, Portugal.
- Centre for Biomedical Research (CBMR), Universidade do Algarve, Faro, Portugal.
- Faculty of Medicine and Biomedical Sciences, University of Algarve, Faro, Portugal.
- Champalimaud Research Program, Champalimaud Center for the Unknown, Lisbon, Portugal.
| |
Collapse
|
26
|
Malcova I, Senohrabkova L, Novakova L, Hasek J. eIF3a Destabilization and TDP-43 Alter Dynamics of Heat-Induced Stress Granules. Int J Mol Sci 2021; 22:ijms22105164. [PMID: 34068231 PMCID: PMC8153170 DOI: 10.3390/ijms22105164] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/04/2021] [Accepted: 05/08/2021] [Indexed: 12/17/2022] Open
Abstract
Stress granules (SGs) are membrane-less assemblies arising upon various stresses in eukaryotic cells. They sequester mRNAs and proteins from stressful conditions and modulate gene expression to enable cells to resume translation and growth after stress relief. SGs containing the translation initiation factor eIF3a/Rpg1 arise in yeast cells upon robust heat shock (HS) at 46 °C only. We demonstrate that the destabilization of Rpg1 within the PCI domain in the Rpg1-3 variant leads to SGs assembly already at moderate HS at 42 °C. These are bona fide SGs arising upon translation arrest containing mRNAs, which are components of the translation machinery, and associating with P-bodies. HS SGs associate with endoplasmatic reticulum and mitochondria and their contact sites ERMES. Although Rpg1-3-labeled SGs arise at a lower temperature, their disassembly is delayed after HS at 46 °C. Remarkably, the delayed disassembly of HS SGs after the robust HS is reversed by TDP-43, which is a human protein connected with amyotrophic lateral sclerosis. TDP-43 colocalizes with HS SGs in yeast cells and facilitates cell regrowth after the stress relief. Based on our results, we propose yeast HS SGs labeled by Rpg1 and its variants as a novel model system to study functions of TDP-43 in stress granules disassembly.
Collapse
Affiliation(s)
- Ivana Malcova
- Institute of Microbiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; (L.S.); (L.N.); (J.H.)
- Correspondence: ; Tel.: +420-241062769
| | - Lenka Senohrabkova
- Institute of Microbiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; (L.S.); (L.N.); (J.H.)
- First Faculty of Medicine, Charles University, Katerinska 42, 12108 Prague, Czech Republic
| | - Lenka Novakova
- Institute of Microbiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; (L.S.); (L.N.); (J.H.)
| | - Jiri Hasek
- Institute of Microbiology, Czech Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic; (L.S.); (L.N.); (J.H.)
| |
Collapse
|
27
|
Schnell HM, Jochem M, Micoogullari Y, Riggs CL, Ivanov P, Welsch H, Ravindran R, Anderson P, Robinson LC, Tatchell K, Hanna J. Reg1 and Snf1 regulate stress-induced relocalization of protein phosphatase-1 to cytoplasmic granules. FEBS J 2021; 288:4833-4848. [PMID: 33682330 DOI: 10.1111/febs.15802] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/22/2021] [Accepted: 03/03/2021] [Indexed: 11/26/2022]
Abstract
The compartmentalization of cellular function is achieved largely through the existence of membrane-bound organelles. However, recent work suggests a novel mechanism of compartmentalization mediated by membraneless structures that have liquid droplet-like properties and arise through phase separation. Cytoplasmic stress granules (SGs) are the best characterized and are induced by various stressors including arsenite, heat shock, and glucose deprivation. Current models suggest that SGs play an important role in protein homeostasis by mediating reversible translation attenuation. Protein phosphatase-1 (PP1) is a central cellular regulator responsible for most serine/threonine dephosphorylation. Here, we show that upon arsenite stress, PP1's catalytic subunit Glc7 relocalizes to punctate cytoplasmic granules. This altered localization requires PP1's recently described maturation pathway mediated by the multifunctional ATPase Cdc48 and PP1's regulatory subunit Ypi1. Glc7 relocalization is mediated by its regulatory subunit Reg1 and its target Snf1, the AMP-dependent protein kinase. Surprisingly, Glc7 granules are highly specific to arsenite and appear distinct from canonical SGs. Arsenite induces potent translational inhibition, and translational recovery is strongly dependent on Glc7, but independent of Glc7's well-established role in regulating eIF2α. These results suggest a novel form of stress-induced cytoplasmic granule and a new mode of translational control by Glc7.
Collapse
Affiliation(s)
- Helena Maria Schnell
- Department of Pathology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA
| | - Marco Jochem
- Department of Pathology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA
| | - Yagmur Micoogullari
- Department of Pathology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA
| | - Claire Louise Riggs
- Department of Rheumatology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA
| | - Pavel Ivanov
- Department of Rheumatology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA
| | - Hendrik Welsch
- Department of Pathology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA
| | - Rini Ravindran
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA, USA
| | - Paul Anderson
- Department of Rheumatology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA
| | - Lucy Christina Robinson
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA, USA
| | - Kelly Tatchell
- Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA, USA
| | - John Hanna
- Department of Pathology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA
| |
Collapse
|
28
|
Barraza CE, Solari CA, Rinaldi J, Ojeda L, Rossi S, Ashe MP, Portela P. A prion-like domain of Tpk2 catalytic subunit of protein kinase A modulates P-body formation in response to stress in budding yeast. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2021; 1868:118884. [PMID: 33039554 DOI: 10.1016/j.bbamcr.2020.118884] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 09/26/2020] [Accepted: 09/29/2020] [Indexed: 01/19/2023]
Abstract
Low complexity regions are involved in the assembly and disassembly of P-bodies (PBs). Saccharomyces cerevisiae contains three genes encoding the protein kinase A (PKA) catalytic subunit: TPK1, TPK2 and TPK3. Tpk2 and Tpk3 isoforms localize to PBs upon glucose starvation showing different mechanisms and kinetics of accumulation. In contrast to the other two isoforms, Tpk2 harbors a glutamine-rich prion-like domain (PrLD) at the N-terminus. Here we show that the appearance of Tpk2 foci in response to glucose starvation, heat stress or stationary phase was dependent on its PrLD. Moreover, the PrLD of Tpk2 was necessary for efficient PB and stress granule aggregation during stress conditions and in quiescent cells. Deletion of PrLD does not affect the in vitro and in vivo kinase activity of Tpk2 or its interaction with the regulatory subunit Bcy1. We present evidence that the PrLD of Tpk2 serves as a scaffold domain for PB assembly in a manner that is independent of Pat1 phosphorylation by PKA. In addition, a mutant strain where Tpk2 lacks PrLD showed a decrease of turnover of mRNA during glucose starvation. This work therefore provides new insight into the mechanism of stress-induced cytoplasmic mRNP assembly, and the role of isoform specific domains in the regulation of PKA catalytic subunit specificity and dynamic localization to cytoplasmic RNPs granules.
Collapse
Affiliation(s)
- Carla E Barraza
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET). Buenos Aires, Argentina.
| | - Clara A Solari
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET). Buenos Aires, Argentina.
| | - Jimena Rinaldi
- Fundación Instituto Leloir, IIBBA-CONICET, Buenos Aires, Argentina.
| | - Lucas Ojeda
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET). Buenos Aires, Argentina.
| | - Silvia Rossi
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET). Buenos Aires, Argentina.
| | - Mark P Ashe
- The Michael Smith Building, Faculty of Life Sciences, University of Manchester, Manchester, UK.
| | - Paula Portela
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas (IQUIBICEN-CONICET). Buenos Aires, Argentina.
| |
Collapse
|
29
|
Adjirackor NA, Harvey KE, Harvey SC. Eukaryotic response to hypothermia in relation to integrated stress responses. Cell Stress Chaperones 2020; 25:833-846. [PMID: 32676830 PMCID: PMC7591648 DOI: 10.1007/s12192-020-01135-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 06/29/2020] [Accepted: 07/01/2020] [Indexed: 12/25/2022] Open
Abstract
Eukaryotic cells respond to hypothermic stress through a series of regulatory mechanisms that preserve energy resources and prolong cell survival. These mechanisms include alterations in gene expression, attenuated global protein synthesis and changes in the lipid composition of the phospholipid bilayer. Cellular responses to hyperthermia, hypoxia, nutrient deprivation and oxidative stress have been comprehensively investigated, but studies of the cellular response to cold stress are more limited. Responses to cold stress are however of great importance both in the wild, where exposure to low and fluctuating environmental temperatures is common, and in medical and biotechnology settings where cells and tissues are frequently exposed to hypothermic stress and cryopreservation. This means that it is vitally important to understand how cells are impacted by low temperatures and by the decreases and subsequent increases in temperature associated with cold stress. Here, we review the ways in which eukaryotic cells respond to hypothermic stress and how these compare to the well-described and highly integrated stress response systems that govern the cellular response to other types of stress.
Collapse
Affiliation(s)
- Naki A Adjirackor
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK.
| | - Katie E Harvey
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
| | - Simon C Harvey
- School of Human and Life Sciences, Canterbury Christ Church University, Canterbury, CT1 1QU, UK
| |
Collapse
|
30
|
O' Neill JS, Hoyle NP, Robertson JB, Edgar RS, Beale AD, Peak-Chew SY, Day J, Costa ASH, Frezza C, Causton HC. Eukaryotic cell biology is temporally coordinated to support the energetic demands of protein homeostasis. Nat Commun 2020; 11:4706. [PMID: 32943618 PMCID: PMC7499178 DOI: 10.1038/s41467-020-18330-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 08/13/2020] [Indexed: 12/17/2022] Open
Abstract
Yeast physiology is temporally regulated, this becomes apparent under nutrient-limited conditions and results in respiratory oscillations (YROs). YROs share features with circadian rhythms and interact with, but are independent of, the cell division cycle. Here, we show that YROs minimise energy expenditure by restricting protein synthesis until sufficient resources are stored, while maintaining osmotic homeostasis and protein quality control. Although nutrient supply is constant, cells sequester and store metabolic resources via increased transport, autophagy and biomolecular condensation. Replete stores trigger increased H+ export which stimulates TORC1 and liberates proteasomes, ribosomes, chaperones and metabolic enzymes from non-membrane bound compartments. This facilitates translational bursting, liquidation of storage carbohydrates, increased ATP turnover, and the export of osmolytes. We propose that dynamic regulation of ion transport and metabolic plasticity are required to maintain osmotic and protein homeostasis during remodelling of eukaryotic proteomes, and that bioenergetic constraints selected for temporal organisation that promotes oscillatory behaviour.
Collapse
Affiliation(s)
- John S O' Neill
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK.
| | | | | | - Rachel S Edgar
- Molecular Virology, Department of Medicine, Imperial College, London, W2 1NY, UK
| | - Andrew D Beale
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | | | - Jason Day
- Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, UK
| | - Ana S H Costa
- MRC Cancer Unit, University of Cambridge, Cambridge, CB2 0XZ, UK.,Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, USA
| | - Christian Frezza
- MRC Cancer Unit, University of Cambridge, Cambridge, CB2 0XZ, UK
| | - Helen C Causton
- Columbia University Medical Center, New York, NY, 10032, USA.
| |
Collapse
|
31
|
Garg M, Poornima G, Rajyaguru PI. Elucidation of the RNA-granule inducing sodium azide stress response through transcriptome analysis. Genomics 2020; 112:2978-2989. [PMID: 32437849 PMCID: PMC7116212 DOI: 10.1016/j.ygeno.2020.05.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 04/30/2020] [Accepted: 05/01/2020] [Indexed: 12/27/2022]
Abstract
Sodium azide is a commonly used cytochrome oxidase inhibitor that leads to translation repression and RNA granule assembly. The global changes in mRNA abundance in response to this stressor are unknown. RGG-motif proteins Scd6 and Sbp1 are translation-repressors and decapping-activators that localize to and affect the assembly of RNA granules in response to sodium azide stress. Transcriptome-wide effects of these proteins remain unknown. To address this, we have sequenced transcriptome of the: a) wild type strain under unstressed and sodium azide stress, b) Δscd6 and Δsbp1 strains under unstressed and sodium azide stress. Transcriptome analysis identified altered abundance of many transcripts belonging to stress-responsive pathways which were further validated by qRT-PCR results. Abundance of several transcripts was altered in Δscd6/Δsbp1 under normal conditions and upon stress. Overall, this study provides critical insights into transcriptome changes in response to sodium azide stress and the role of RGG-motif proteins in these changes.
Collapse
Affiliation(s)
- Mani Garg
- Department of Biochemistry, Indian Institute of Science, Bangalore 560012, India
| | | | | |
Collapse
|
32
|
Jang GJ, Jang JC, Wu SH. Dynamics and Functions of Stress Granules and Processing Bodies in Plants. PLANTS 2020; 9:plants9091122. [PMID: 32872650 PMCID: PMC7570210 DOI: 10.3390/plants9091122] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/25/2020] [Accepted: 08/26/2020] [Indexed: 12/23/2022]
Abstract
RNA granules, such as stress granules and processing bodies, can balance the storage, degradation, and translation of mRNAs in diverse eukaryotic organisms. The sessile nature of plants demands highly versatile strategies to respond to environmental fluctuations. In this review, we discuss recent findings of the dynamics and functions of these RNA granules in plants undergoing developmental reprogramming or responding to environmental stresses. Special foci include the dynamic assembly, disassembly, and regulatory roles of these RNA granules in determining the fate of mRNAs.
Collapse
Affiliation(s)
- Geng-Jen Jang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan;
| | - Jyan-Chyun Jang
- Department of Horticulture and Crop Science, Department of Molecular Genetics, Center for Applied Plant Sciences, Center for RNA Biology, Ohio State University, Columbus, OH 43210, USA;
| | - Shu-Hsing Wu
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan;
- Correspondence: ; Tel.: +886-2-2787-1178
| |
Collapse
|
33
|
Begovich K, Wilhelm JE. An In Vitro Assembly System Identifies Roles for RNA Nucleation and ATP in Yeast Stress Granule Formation. Mol Cell 2020; 79:991-1007.e4. [PMID: 32780990 DOI: 10.1016/j.molcel.2020.07.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 05/22/2020] [Accepted: 07/17/2020] [Indexed: 01/08/2023]
Abstract
Stress granules (SGs) are condensates of mRNPs that form in response to stress. SGs arise by multivalent protein-protein, protein-RNA, and RNA-RNA interactions. However, the role of RNA-RNA interactions in SG assembly remains understudied. Here, we describe a yeast SG reconstitution system that faithfully recapitulates SG assembly in response to trigger RNAs. SGs assembled by stem-loop RNA triggers are ATP-sensitive, regulated by helicase/chaperone activity, and exhibit the hallmarks of maturation observed for SG proteins that phase-separate in vitro. Additionally, the fraction of total RNA that phase-separates in vitro is sufficient to trigger SG formation. However, condensation of NFT1 mRNA, an enriched transcript in this population, can only assemble an incomplete SG. These results suggest that networks of distinct transcripts are required to form a canonical SG and provide a platform for dissecting the interplay between the transcriptome and ATP-dependent remodeling in SG formation.
Collapse
Affiliation(s)
- Kyle Begovich
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA; Howard Hughes Medical Institute (HHMI) Summer Institute Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - James E Wilhelm
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA; Howard Hughes Medical Institute (HHMI) Summer Institute Marine Biological Laboratory, Woods Hole, MA 02543, USA.
| |
Collapse
|
34
|
Nüske E, Marini G, Richter D, Leng W, Bogdanova A, Franzmann TM, Pigino G, Alberti S. Filament formation by the translation factor eIF2B regulates protein synthesis in starved cells. Biol Open 2020; 9:bio046391. [PMID: 32554487 PMCID: PMC7358136 DOI: 10.1242/bio.046391] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 05/26/2020] [Indexed: 12/11/2022] Open
Abstract
Cells exposed to starvation have to adjust their metabolism to conserve energy and protect themselves. Protein synthesis is one of the major energy-consuming processes and as such has to be tightly controlled. Many mechanistic details about how starved cells regulate the process of protein synthesis are still unknown. Here, we report that the essential translation initiation factor eIF2B forms filaments in starved budding yeast cells. We demonstrate that filamentation is triggered by starvation-induced acidification of the cytosol, which is caused by an influx of protons from the extracellular environment. We show that filament assembly by eIF2B is necessary for rapid and efficient downregulation of translation. Importantly, this mechanism does not require the kinase Gcn2. Furthermore, analysis of site-specific variants suggests that eIF2B assembly results in enzymatically inactive filaments that promote stress survival and fast recovery of cells from starvation. We propose that translation regulation through filament assembly is an efficient mechanism that allows yeast cells to adapt to fluctuating environments.
Collapse
Affiliation(s)
- Elisabeth Nüske
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Guendalina Marini
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Doris Richter
- Department of Cellular Biochemistry Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Weihua Leng
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Aliona Bogdanova
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Titus M Franzmann
- Department of Cellular Biochemistry Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| | - Gaia Pigino
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Simon Alberti
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
- Department of Cellular Biochemistry Biotechnology Center (BIOTEC), Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
| |
Collapse
|
35
|
Fission Yeast Puf2, a Pumilio and FBF Family RNA-Binding Protein, Links Stress Granules to Processing Bodies. Mol Cell Biol 2020; 40:MCB.00589-19. [PMID: 32071154 DOI: 10.1128/mcb.00589-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 02/12/2020] [Indexed: 11/20/2022] Open
Abstract
Stress granules (SGs) are cytoplasmic aggregates formed upon stress when untranslated messenger ribonucleoproteins accumulate in the cells. In a green fluorescent protein library screening of the fission yeast SG proteins, Puf2 of the PUF family of RNA-binding proteins was identified that is required for SG formation after deprivation of glucose. Accordingly, the puf2 mutant is defective in recovery from glucose starvation with a much longer lag to reenter the cell cycle. In keeping with these results, Puf2 contains several low-complexity and intrinsically disordered protein regions with a tendency to form aggregates and, when overexpressed, it represses translation to induce aggregation of poly(A) binding protein Pabp, the signature constituent of SGs. Intriguingly, overexpression of Puf2 also enhances the structure of processing bodies (PBs), another type of cytoplasmic RNA granule, a complex of factors involved in mRNA degradation. In this study, we demonstrate a function of the fission yeast PB in SG formation and show Puf2 may provide a link between these two structures.
Collapse
|
36
|
eIF4E and Interactors from Unicellular Eukaryotes. Int J Mol Sci 2020; 21:ijms21062170. [PMID: 32245232 PMCID: PMC7139794 DOI: 10.3390/ijms21062170] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 03/12/2020] [Accepted: 03/18/2020] [Indexed: 12/22/2022] Open
Abstract
eIF4E, the mRNA cap-binding protein, is well known as a general initiation factor allowing for mRNA-ribosome interaction and cap-dependent translation in eukaryotic cells. In this review we focus on eIF4E and its interactors in unicellular organisms such as yeasts and protozoan eukaryotes. In a first part, we describe eIF4Es from yeast species such as Saccharomyces cerevisiae, Candida albicans, and Schizosaccharomyces pombe. In the second part, we will address eIF4E and interactors from parasite unicellular species—trypanosomatids and marine microorganisms—dinoflagellates. We propose that different strategies have evolved during evolution to accommodate cap-dependent translation to differing requirements. These evolutive “adjustments” involve various forms of eIF4E that are not encountered in all microorganismic species. In yeasts, eIF4E interactors, particularly p20 and Eap1 are found exclusively in Saccharomycotina species such as S. cerevisiae and C. albicans. For protozoan parasites of the Trypanosomatidae family beside a unique cap4-structure located at the 5′UTR of all mRNAs, different eIF4Es and eIF4Gs are active depending on the life cycle stage of the parasite. Additionally, an eIF4E-interacting protein has been identified in Leishmania major which is important for switching from promastigote to amastigote stages. For dinoflagellates, little is known about the structure and function of the multiple and diverse eIF4Es that have been identified thanks to widespread sequencing in recent years.
Collapse
|
37
|
Dubiel M, De Coninck T, Osterne VJS, Verbeke I, Van Damme D, Smagghe G, Van Damme EJM. The ArathEULS3 Lectin Ends up in Stress Granules and Can Follow an Unconventional Route for Secretion. Int J Mol Sci 2020; 21:E1659. [PMID: 32121292 PMCID: PMC7084908 DOI: 10.3390/ijms21051659] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 12/26/2022] Open
Abstract
Stress granules are cytoplasmic compartments, which serve as mRNA storage units during stress, therefore regulating translation. The Arabidopsis thaliana lectin ArathEULS3 has been widely described as a stress inducible gene. This study aimed to examine in detail the localization of ArathEULS3 lectin in normal and stressed cells. Colocalization experiments revealed that the nucleo-cytoplasmic lectin ArathEULS3 relocates to stress granules after stress. The ArathEULS3 sequence encodes a protein with a EUL lectin domain and an N-terminal domain with unknown structure and function. Bioinformatics analyses showed that the N-terminal domain sequence contains intrinsically disordered regions and likely does not exhibit a stable protein fold. Plasmolysis experiments indicated that ArathEULS3 also localizes to the apoplast, suggesting that this protein might follow an unconventional route for secretion. As part of our efforts we also investigated the interactome of ArathEULS3 and identified several putative interaction partners important for the protein translation process.
Collapse
Affiliation(s)
- Malgorzata Dubiel
- Laboratory of Biochemistry and Glycobiology, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
- Laboratory of Agrozoology, Department of Plants and Crops, Ghent University, 9000 Ghent, Belgium
| | - Tibo De Coninck
- Laboratory of Biochemistry and Glycobiology, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Vinicius Jose Silva Osterne
- Laboratory of Biochemistry and Glycobiology, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
- Laboratório de Moléculas Biologicamente Ativas, Universidade Federal do Ceará, José Aurelio Camara, S/N, 61440-970, Fortaleza 60440-970, Brazil
| | - Isabel Verbeke
- Laboratory of Biochemistry and Glycobiology, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Daniël Van Damme
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 71, 9052 Ghent, Belgium
- VIB Center for Plant Systems Biology, Technologiepark 71, 9052 Ghent, Belgium
| | - Guy Smagghe
- Laboratory of Agrozoology, Department of Plants and Crops, Ghent University, 9000 Ghent, Belgium
| | - Els J M Van Damme
- Laboratory of Biochemistry and Glycobiology, Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
- Center for Advanced Light Microscopy, Ghent University, 9000 Ghent, Belgium
| |
Collapse
|
38
|
Bridging biophysics and neurology: aberrant phase transitions in neurodegenerative disease. Nat Rev Neurol 2020; 15:272-286. [PMID: 30890779 DOI: 10.1038/s41582-019-0157-5] [Citation(s) in RCA: 123] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Biomolecular condensation arising through phase transitions has emerged as an essential organizational strategy that governs many aspects of cell biology. In particular, the role of phase transitions in the assembly of large, complex ribonucleoprotein (RNP) granules has become appreciated as an important regulator of RNA metabolism. In parallel, genetic, histopathological and cell and molecular studies have provided evidence that disturbance of phase transitions is an important driver of neurological diseases, notably amyotrophic lateral sclerosis (ALS), but most likely also other diseases. Indeed, our growing knowledge of the biophysics underlying biological phase transitions suggests that this process offers a unifying mechanism to explain the numerous and diverse disturbances in RNA metabolism that have been observed in ALS and some related diseases - specifically, that these diseases are driven by disturbances in the material properties of RNP granules. Here, we review the evidence for this hypothesis, emphasizing the reciprocal roles in which disease-related protein and disease-related RNA can lead to disturbances in the material properties of RNP granules and consequent pathogenesis. Additionally, we review evidence that implicates aberrant phase transitions as a contributing factor to a larger set of neurodegenerative diseases, including frontotemporal dementia, certain repeat expansion diseases and Alzheimer disease.
Collapse
|
39
|
Belli V, Matrone N, Sagliocchi S, Incarnato R, Conte A, Pizzo E, Turano M, Angrisani A, Furia M. A dynamic link between H/ACA snoRNP components and cytoplasmic stress granules. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2019; 1866:118529. [DOI: 10.1016/j.bbamcr.2019.118529] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 07/08/2019] [Accepted: 08/05/2019] [Indexed: 02/06/2023]
|
40
|
van Leeuwen W, Rabouille C. Cellular stress leads to the formation of membraneless stress assemblies in eukaryotic cells. Traffic 2019; 20:623-638. [PMID: 31152627 PMCID: PMC6771618 DOI: 10.1111/tra.12669] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/10/2019] [Accepted: 05/30/2019] [Indexed: 12/28/2022]
Abstract
In cells at steady state, two forms of cell compartmentalization coexist: membrane-bound organelles and phase-separated membraneless organelles that are present in both the nucleus and the cytoplasm. Strikingly, cellular stress is a strong inducer of the reversible membraneless compartments referred to as stress assemblies. Stress assemblies play key roles in survival during cell stress and in thriving of cells upon stress relief. The two best studied stress assemblies are the RNA-based processing-bodies (P-bodies) and stress granules that form in response to oxidative, endoplasmic reticulum (ER), osmotic and nutrient stress as well as many others. Interestingly, P-bodies and stress granules are heterogeneous with respect to both the pathways that lead to their formation and their protein and RNA content. Furthermore, in yeast and Drosophila, nutrient stress also leads to the formation of many other types of prosurvival cytoplasmic stress assemblies, such as metabolic enzymes foci, proteasome storage granules, EIF2B bodies, U-bodies and Sec bodies, some of which are not RNA-based. Nutrient stress leads to a drop in cytoplasmic pH, which combined with posttranslational modifications of granule contents, induces phase separation.
Collapse
Affiliation(s)
- Wessel van Leeuwen
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciencesand University Medical Center UtrechtUtrechtthe Netherlands
| | - Catherine Rabouille
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciencesand University Medical Center UtrechtUtrechtthe Netherlands
- Department of Biomedical Science of Cells and SystemsUniversity Medical Center GroningenGroningenthe Netherlands
| |
Collapse
|
41
|
Janapala Y, Preiss T, Shirokikh NE. Control of Translation at the Initiation Phase During Glucose Starvation in Yeast. Int J Mol Sci 2019; 20:E4043. [PMID: 31430885 PMCID: PMC6720308 DOI: 10.3390/ijms20164043] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/10/2019] [Accepted: 08/15/2019] [Indexed: 12/13/2022] Open
Abstract
Glucose is one of the most important sources of carbon across all life. Glucose starvation is a key stress relevant to all eukaryotic cells. Glucose starvation responses have important implications in diseases, such as diabetes and cancer. In yeast, glucose starvation causes rapid and dramatic effects on the synthesis of proteins (mRNA translation). Response to glucose deficiency targets the initiation phase of translation by different mechanisms and with diverse dynamics. Concomitantly, translationally repressed mRNAs and components of the protein synthesis machinery may enter a variety of cytoplasmic foci, which also form with variable kinetics and may store or degrade mRNA. Much progress has been made in understanding these processes in the last decade, including with the use of high-throughput/omics methods of RNA and RNA:protein detection. This review dissects the current knowledge of yeast reactions to glucose starvation systematized by the stage of translation initiation, with the focus on rapid responses. We provide parallels to mechanisms found in higher eukaryotes, such as metazoans, for the most critical responses, and point out major remaining gaps in knowledge and possible future directions of research on translational responses to glucose starvation.
Collapse
Affiliation(s)
- Yoshika Janapala
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia
| | - Thomas Preiss
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia.
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.
| | - Nikolay E Shirokikh
- EMBL-Australia Collaborating Group, Department of Genome Sciences, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 2601, Australia.
| |
Collapse
|
42
|
Guin D, Gruebele M. Weak Chemical Interactions That Drive Protein Evolution: Crowding, Sticking, and Quinary Structure in Folding and Function. Chem Rev 2019; 119:10691-10717. [PMID: 31356058 DOI: 10.1021/acs.chemrev.8b00753] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In recent years, better instrumentation and greater computing power have enabled the imaging of elusive biomolecule dynamics in cells, driving many advances in understanding the chemical organization of biological systems. The focus of this Review is on interactions in the cell that affect both biomolecular stability and function and modulate them. The same protein or nucleic acid can behave differently depending on the time in the cell cycle, the location in a specific compartment, or the stresses acting on the cell. We describe in detail the crowding, sticking, and quinary structure in the cell and the current methods to quantify them both in vitro and in vivo. Finally, we discuss protein evolution in the cell in light of current biophysical evidence. We describe the factors that drive protein evolution and shape protein interaction networks. These interactions can significantly affect the free energy, ΔG, of marginally stable and low-population proteins and, due to epistasis, direct the evolutionary pathways in an organism. We finally conclude by providing an outlook on experiments to come and the possibility of collaborative evolutionary biology and biophysical efforts.
Collapse
Affiliation(s)
- Drishti Guin
- Department of Chemistry , University of Illinois , Urbana , Illinois 61801 , United States
| | - Martin Gruebele
- Department of Chemistry , University of Illinois , Urbana , Illinois 61801 , United States.,Department of Physics , University of Illinois , Urbana , Illinois 61801 , United States.,Center for Biophysics and Quantitative Biology , University of Illinois , Urbana , Illinois 61801 , United States
| |
Collapse
|
43
|
Garcia-Jove Navarro M, Kashida S, Chouaib R, Souquere S, Pierron G, Weil D, Gueroui Z. RNA is a critical element for the sizing and the composition of phase-separated RNA-protein condensates. Nat Commun 2019; 10:3230. [PMID: 31324804 PMCID: PMC6642089 DOI: 10.1038/s41467-019-11241-6] [Citation(s) in RCA: 128] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 06/27/2019] [Indexed: 01/01/2023] Open
Abstract
Liquid-liquid phase separation is thought to be a key organizing principle in eukaryotic cells to generate highly concentrated dynamic assemblies, such as the RNP granules. Numerous in vitro approaches have validated this model, yet a missing aspect is to take into consideration the complex molecular mixture and promiscuous interactions found in vivo. Here we report the versatile scaffold ArtiG to generate concentration-dependent RNA-protein condensates within living cells, as a bottom-up approach to study the impact of co-segregated endogenous components on phase separation. We demonstrate that intracellular RNA seeds the nucleation of the condensates, as it provides molecular cues to locally coordinate the formation of endogenous high-order RNP assemblies. Interestingly, the co-segregation of intracellular components ultimately impacts the size of the phase-separated condensates. Thus, RNA arises as an architectural element that can influence the composition and the morphological outcome of the condensate phases in an intracellular context.
Collapse
Affiliation(s)
- Marina Garcia-Jove Navarro
- PASTEUR, Department of Chemistry, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France
| | - Shunnichi Kashida
- PASTEUR, Department of Chemistry, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France
| | - Racha Chouaib
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire de Biologie du Développement, F-75005, Paris, France.,School of Arts and Sciences, Lebanese International University (LIU), Beirut, Lebanon.,Faculty of Sciences, Lebanese University, Beirut, Lebanon
| | - Sylvie Souquere
- CNRS UMR-9196, Institut Gustave Roussy, F-94800, Villejuif, France
| | - Gérard Pierron
- CNRS UMR-9196, Institut Gustave Roussy, F-94800, Villejuif, France
| | - Dominique Weil
- Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Laboratoire de Biologie du Développement, F-75005, Paris, France
| | - Zoher Gueroui
- PASTEUR, Department of Chemistry, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005, Paris, France.
| |
Collapse
|
44
|
Pizzinga M, Bates C, Lui J, Forte G, Morales-Polanco F, Linney E, Knotkova B, Wilson B, Solari CA, Berchowitz LE, Portela P, Ashe MP. Translation factor mRNA granules direct protein synthetic capacity to regions of polarized growth. J Cell Biol 2019; 218:1564-1581. [PMID: 30877141 PMCID: PMC6504908 DOI: 10.1083/jcb.201704019] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 11/12/2018] [Accepted: 02/28/2019] [Indexed: 12/22/2022] Open
Abstract
mRNA localization serves key functions in localized protein production, making it critical that the translation machinery itself is present at these locations. Here we show that translation factor mRNAs are localized to distinct granules within yeast cells. In contrast to many messenger RNP granules, such as processing bodies and stress granules, which contain translationally repressed mRNAs, these granules harbor translated mRNAs under active growth conditions. The granules require Pab1p for their integrity and are inherited by developing daughter cells in a She2p/She3p-dependent manner. These results point to a model where roughly half the mRNA for certain translation factors is specifically directed in granules or translation factories toward the tip of the developing daughter cell, where protein synthesis is most heavily required, which has particular implications for filamentous forms of growth. Such a feedforward mechanism would ensure adequate provision of the translation machinery where it is to be needed most over the coming growth cycle.
Collapse
Affiliation(s)
- Mariavittoria Pizzinga
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Christian Bates
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Jennifer Lui
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Gabriella Forte
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Fabián Morales-Polanco
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Emma Linney
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Barbora Knotkova
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Beverley Wilson
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Clara A Solari
- Universidad de Buenos Aires, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Luke E Berchowitz
- Department of Genetics and Development, Hammer Health Sciences Center, Columbia University Medical Center, New York, NY
| | - Paula Portela
- Universidad de Buenos Aires, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales-Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Mark P Ashe
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| |
Collapse
|
45
|
Kosmacz M, Gorka M, Schmidt S, Luzarowski M, Moreno JC, Szlachetko J, Leniak E, Sokolowska EM, Sofroni K, Schnittger A, Skirycz A. Protein and metabolite composition of Arabidopsis stress granules. THE NEW PHYTOLOGIST 2019; 222:1420-1433. [PMID: 30664249 DOI: 10.1111/nph.15690] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 01/11/2019] [Indexed: 05/06/2023]
Abstract
Stress granules (SGs) are evolutionary conserved aggregates of proteins and untranslated mRNAs formed in response to stress. Despite their importance for stress adaptation, no complete proteome composition has been reported for plant SGs. In this study, we addressed the existing gap. Importantly, we also provide evidence for metabolite sequestration within the SGs. To isolate SGs we used Arabidopsis seedlings expressing green fluorescent protein (GFP) fusion of the SGs marker protein, Rbp47b, and an experimental protocol combining differential centrifugation with affinity purification (AP). SGs isolates were analysed using mass spectrometry-based proteomics and metabolomics. A quarter of the identified proteins constituted known or predicted SG components. Intriguingly, the remaining proteins were enriched in key enzymes and regulators, such as cyclin-dependent kinase A (CDKA), that mediate plant responses to stress. In addition to proteins, nucleotides, amino acids and phospholipids also accumulated in SGs. Taken together, our results indicated the presence of a preexisting SG protein interaction network; an evolutionary conservation of the proteins involved in SG assembly and dynamics; an important role for SGs in moderation of stress responses by selective storage of proteins and metabolites.
Collapse
Affiliation(s)
- Monika Kosmacz
- Max Planck Institute of Molecular Plant Physiology, 14476, Potsdam, Germany
| | - Michał Gorka
- Max Planck Institute of Molecular Plant Physiology, 14476, Potsdam, Germany
| | - Stephan Schmidt
- Max Planck Institute of Molecular Plant Physiology, 14476, Potsdam, Germany
| | - Marcin Luzarowski
- Max Planck Institute of Molecular Plant Physiology, 14476, Potsdam, Germany
| | - Juan C Moreno
- Max Planck Institute of Molecular Plant Physiology, 14476, Potsdam, Germany
| | - Jagoda Szlachetko
- Max Planck Institute of Molecular Plant Physiology, 14476, Potsdam, Germany
| | - Ewa Leniak
- Max Planck Institute of Molecular Plant Physiology, 14476, Potsdam, Germany
| | | | - Kostika Sofroni
- Department of Developmental Biology, University of Hamburg, 22069, Hamburg, Germany
| | - Arp Schnittger
- Department of Developmental Biology, University of Hamburg, 22069, Hamburg, Germany
| | - Aleksandra Skirycz
- Max Planck Institute of Molecular Plant Physiology, 14476, Potsdam, Germany
| |
Collapse
|
46
|
Yoo H, Triandafillou C, Drummond DA. Cellular sensing by phase separation: Using the process, not just the products. J Biol Chem 2019; 294:7151-7159. [PMID: 30877200 DOI: 10.1074/jbc.tm118.001191] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Phase separation creates two distinct liquid phases from a single mixed liquid phase, like oil droplets separating from water. Considerable attention has focused on how the products of phase separation-the resulting condensates-might act as biological compartments, bioreactors, filters, and membraneless organelles in cells. Here, we expand this perspective, reviewing recent results showing how cells instead use the process of phase separation to sense intracellular and extracellular changes. We review case studies in phase separation-based sensing and discuss key features, such as extraordinary sensitivity, which make the process of phase separation ideally suited to meet a range of sensory challenges cells encounter.
Collapse
Affiliation(s)
- Haneul Yoo
- From the Department of Biochemistry and Molecular Biology
| | | | - D Allan Drummond
- From the Department of Biochemistry and Molecular Biology, .,Department of Human Genetics, University of Chicago, Chicago, Illinois 60637
| |
Collapse
|
47
|
Signalling through the yeast MAPK Cell Wall Integrity pathway controls P-body assembly upon cell wall stress. Sci Rep 2019; 9:3186. [PMID: 30816278 PMCID: PMC6395727 DOI: 10.1038/s41598-019-40112-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 02/11/2019] [Indexed: 01/15/2023] Open
Abstract
Post-transcriptional control of mRNA is a key event in the regulation of gene expression. From yeast to human cells, P-bodies are cytoplasmic RNA-protein aggregates that play an essential role in this process, particularly under stress conditions. In this work, we show that in the model yeast Saccharomyces cerevisiae cell wall stress induces the formation of these structures. This effect is dependent on multiple elements in the Cell Wall Integrity (CWI) MAPK signalling pathway, a signal transduction cascade responsible for the maintenance of cell integrity under adverse environmental conditions. Remarkably, P-body assembly requires the catalytic activity of the MAPK of the pathway, Slt2/Mpk1. In accordance with the control exerted by this signalling pathway, the timing of P-body formation is similar to that of the activation of the CWI pathway. Noticeably, mRNAs whose expression is regulated by this pathway localize in P-bodies after the cell is exposed to stress following a temporal pattern coincident with CWI pathway activation. Moreover, when these mRNAs are overexpressed in a mutant background unable to form visible P-bodies, the cells show hypersensitivity to agents that interfere with cell wall integrity, supporting that they play a role in the mRNA lifecycle under stress conditions.
Collapse
|
48
|
Brambilla M, Martani F, Bertacchi S, Vitangeli I, Branduardi P. The Saccharomyces cerevisiae
poly (A) binding protein (Pab1): Master regulator of mRNA metabolism and cell physiology. Yeast 2018; 36:23-34. [DOI: 10.1002/yea.3347] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 06/26/2018] [Accepted: 07/06/2018] [Indexed: 12/15/2022] Open
Affiliation(s)
- Marco Brambilla
- Department of Biotechnology and Biosciences; University of Milano-Bicocca; Piazza della Scienza 2 20126 Milan Italy
| | - Francesca Martani
- Department of Biotechnology and Biosciences; University of Milano-Bicocca; Piazza della Scienza 2 20126 Milan Italy
| | - Stefano Bertacchi
- Department of Biotechnology and Biosciences; University of Milano-Bicocca; Piazza della Scienza 2 20126 Milan Italy
| | - Ilaria Vitangeli
- Department of Biotechnology and Biosciences; University of Milano-Bicocca; Piazza della Scienza 2 20126 Milan Italy
| | - Paola Branduardi
- Department of Biotechnology and Biosciences; University of Milano-Bicocca; Piazza della Scienza 2 20126 Milan Italy
| |
Collapse
|
49
|
Crawford RA, Pavitt GD. Translational regulation in response to stress in Saccharomyces cerevisiae. Yeast 2018; 36:5-21. [PMID: 30019452 PMCID: PMC6492140 DOI: 10.1002/yea.3349] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 06/08/2018] [Accepted: 06/25/2018] [Indexed: 12/19/2022] Open
Abstract
The budding yeast Saccharomyces cerevisiae must dynamically alter the composition of its proteome in order to respond to diverse stresses. The reprogramming of gene expression during stress typically involves initial global repression of protein synthesis, accompanied by the activation of stress‐responsive mRNAs through both translational and transcriptional responses. The ability of specific mRNAs to counter the global translational repression is therefore crucial to the overall response to stress. Here we summarize the major repressive mechanisms and discuss mechanisms of translational activation in response to different stresses in S. cerevisiae. Taken together, a wide range of studies indicate that multiple elements act in concert to bring about appropriate translational responses. These include regulatory elements within mRNAs, altered mRNA interactions with RNA‐binding proteins and the specialization of ribosomes that each contribute towards regulating protein expression to suit the changing environmental conditions.
Collapse
Affiliation(s)
- Robert A Crawford
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Michael Smith Building, Dover Street, Manchester, M13 9PT, UK
| | - Graham D Pavitt
- Division of Molecular and Cellular Function, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Michael Smith Building, Dover Street, Manchester, M13 9PT, UK
| |
Collapse
|
50
|
Moujaber O, Stochaj U. Cytoplasmic RNA Granules in Somatic Maintenance. Gerontology 2018; 64:485-494. [PMID: 29847814 DOI: 10.1159/000488759] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 03/26/2018] [Indexed: 12/19/2022] Open
Abstract
Cytoplasmic RNA granules represent subcellular compartments that are enriched in protein-bound RNA species. RNA granules are produced by evolutionary divergent eukaryotes, including yeast, mammals, and plants. The functions of cytoplasmic RNA granules differ widely. They are dictated by the cell type and physiological state, which in turn is determined by intrinsic cell properties and environmental factors. RNA granules provide diverse cellular functions. However, all of the granules contribute to aspects of RNA metabolism. This is exemplified by transcription, RNA storage, silencing, and degradation, as well as mRNP remodeling and regulated translation. Several forms of cytoplasmic mRNA granules are linked to normal physiological processes. For instance, they may coordinate protein synthesis and thereby serve as posttranscriptional "operons". RNA granules also participate in cytoplasmic mRNA trafficking, a process particularly well understood for neurons. Many forms of RNA granules support the preservation of somatic cell performance under normal and stress conditions. On the other hand, severe insults or disease can cause the formation and persistence of RNA granules that contribute to cellular dysfunction, especially in the nervous system. Neurodegeneration and many other diseases linked to RNA granules are associated with aging. Nevertheless, information related to the impact of aging on the various types of RNA granules is presently very limited. This review concentrates on cytoplasmic RNA granules and their role in somatic cell maintenance. We summarize the current knowledge on different types of RNA granules in the cytoplasm, their assembly and function under normal, stress, or disease conditions. Specifically, we discuss processing bodies, neuronal granules, stress granules, and other less characterized cytoplasmic RNA granules. Our focus is primarily on mammalian and yeast models, because they have been critical to unravel the physiological role of various RNA granules. RNA granules in plants and pathogens are briefly described. We conclude our viewpoint by summarizing the emerging concepts for RNA granule biology and the open questions that need to be addressed in future studies.
Collapse
|