1
|
Hall RA, Wallace EW. Post-transcriptional control of fungal cell wall synthesis. Cell Surf 2022; 8:100074. [PMID: 35097244 PMCID: PMC8783092 DOI: 10.1016/j.tcsw.2022.100074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/10/2022] [Accepted: 01/10/2022] [Indexed: 12/21/2022] Open
Abstract
Pathogenic fungi hide from their hosts by camouflage, obscuring immunogenic cell wall components such as beta-glucan with innocuous coverings such as mannoproteins and alpha-glucan that are less readily recognised by the host. Attempts to understand how such processes are regulated have met with varying success. Typically studies focus on understanding the transcriptional response of fungi to either their reservoir environment or the host. However, such approaches do not fully address this research question, due to the layers of post-transcriptional and post-translational regulation that occur within a cell. Although in animals the impact of post-transcriptional and post-translational regulation has been well characterised, our knowledge of these processes in the fungal kingdom is more limited. Mutations in RNA-binding proteins, like Ssd1 and Candida albicans Slr1, affect cell wall composition and fungal virulence indicating that post-transcriptional regulation plays a key role in these processes. Here, we review the current state of knowledge of fungal post-transcriptional regulation, and link this to potential mechanisms of immune evasion by drawing on studies from model yeast and plant pathogenic fungi. We highlight several RNA-binding proteins that regulate cell wall synthesis and could be involved in local translation of cell wall components. Expanding our knowledge on post-transcriptional regulation in human fungal pathogens is essential to fully comprehend fungal virulence strategies and for the design of novel antifungal therapies.
Collapse
Affiliation(s)
- Rebecca A. Hall
- Kent Fungal Group, Division of Natural Sciences, School of Biosciences, University of Kent, Canterbury CT2 7NJ, United Kingdom
| | - Edward W.J. Wallace
- Institute for Cell Biology and SynthSys, School of Biological Sciences, University of Edinburgh, EH9 3FF, United Kingdom
| |
Collapse
|
2
|
Hydrogen peroxide initiates oxidative stress and proteomic alterations in meningothelial cells. Sci Rep 2022; 12:14519. [PMID: 36008468 PMCID: PMC9411503 DOI: 10.1038/s41598-022-18548-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 08/16/2022] [Indexed: 11/26/2022] Open
Abstract
Meningothelial cells (MECs) are fundamental cells of the sheaths covering the brain and optic nerve, where they build a brain/optic nerve-cerebral spinal fluid (CSF) barrier that prevents the free flow of CSF from the subarachnoid space, but their exact roles and underlying mechanisms remain unclear. Our attempt here was to investigate the influence elicited by hydrogen peroxide (H2O2) on functional changes of MECs. Our study showed that cell viability of MECs was inhibited after cells were exposed to oxidative agents. Cells subjected to H2O2 at the concentration of 150 µM for 24 h and 48 h exhibited an elevation of reactive oxygen species (ROS) activity, decrease of total antioxidant capacity (T-AOC) level and reduced mitochondrial membrane potential (ΔΨm) compared with control cells. 95 protein spots with more than twofold difference were detected in two dimensional electrophoresis (2DE) gels through proteomics assay following H2O2 exposure for 48 h, 10 proteins were identified through TOF/MS analysis. Among the proteomic changes explored, 8 proteins related to energy metabolism, mitochondrial function, structural regulation, and cell cycle control were downregulated. Our study provides key insights that enhance our understanding of the role of MECs in the pathology of brain and optic nerve disorders.
Collapse
|
3
|
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
|
4
|
Rehbein U, Prentzell MT, Cadena Sandoval M, Heberle AM, Henske EP, Opitz CA, Thedieck K. The TSC Complex-mTORC1 Axis: From Lysosomes to Stress Granules and Back. Front Cell Dev Biol 2021; 9:751892. [PMID: 34778262 PMCID: PMC8586448 DOI: 10.3389/fcell.2021.751892] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 10/05/2021] [Indexed: 12/14/2022] Open
Abstract
The tuberous sclerosis protein complex (TSC complex) is a key integrator of metabolic signals and cellular stress. In response to nutrient shortage and stresses, the TSC complex inhibits the mechanistic target of rapamycin complex 1 (mTORC1) at the lysosomes. mTORC1 is also inhibited by stress granules (SGs), RNA-protein assemblies that dissociate mTORC1. The mechanisms of lysosome and SG recruitment of mTORC1 are well studied. In contrast, molecular details on lysosomal recruitment of the TSC complex have emerged only recently. The TSC complex subunit 1 (TSC1) binds lysosomes via phosphatidylinositol-3,5-bisphosphate [PI(3,5)P2]. The SG assembly factors 1 and 2 (G3BP1/2) have an unexpected lysosomal function in recruiting TSC2 when SGs are absent. In addition, high density lipoprotein binding protein (HDLBP, also named Vigilin) recruits TSC2 to SGs under stress. In this mini-review, we integrate the molecular mechanisms of lysosome and SG recruitment of the TSC complex. We discuss their interplay in the context of cell proliferation and migration in cancer and in the clinical manifestations of tuberous sclerosis complex disease (TSC) and lymphangioleiomyomatosis (LAM).
Collapse
Affiliation(s)
- Ulrike Rehbein
- Laboratory for Metabolic Signaling, Institute of Biochemistry, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
| | - Mirja Tamara Prentzell
- Brain Cancer Metabolism Group, German Consortium of Translational Cancer Research (DKTK) & German Cancer Research Center (DKFZ), Heidelberg, Germany
- Faculty of Bioscience, Heidelberg University, Heidelberg, Germany
| | - Marti Cadena Sandoval
- Laboratory for Metabolic Signaling, Institute of Biochemistry, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
- Section Systems Medicine of Metabolism and Signaling, Department of Pediatrics, University of Groningen and University Medical Center Groningen, Groningen, Netherlands
| | - Alexander Martin Heberle
- Laboratory for Metabolic Signaling, Institute of Biochemistry, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
- Section Systems Medicine of Metabolism and Signaling, Department of Pediatrics, University of Groningen and University Medical Center Groningen, Groningen, Netherlands
| | - Elizabeth P. Henske
- Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Christiane A. Opitz
- Brain Cancer Metabolism Group, German Consortium of Translational Cancer Research (DKTK) & German Cancer Research Center (DKFZ), Heidelberg, Germany
- Department of Neurology, National Center for Tumor Diseases, University Hospital Heidelberg, Heidelberg, Germany
| | - Kathrin Thedieck
- Laboratory for Metabolic Signaling, Institute of Biochemistry, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
- Section Systems Medicine of Metabolism and Signaling, Department of Pediatrics, University of Groningen and University Medical Center Groningen, Groningen, Netherlands
- Department for Neuroscience, School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| |
Collapse
|
5
|
The Putative RNA-Binding Protein Dri1 Promotes the Loading of Kinesin-14/Klp2 to the Mitotic Spindle and Is Sequestered into Heat-Induced Protein Aggregates in Fission Yeast. Int J Mol Sci 2021; 22:ijms22094795. [PMID: 33946513 PMCID: PMC8125374 DOI: 10.3390/ijms22094795] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/21/2021] [Accepted: 04/29/2021] [Indexed: 12/23/2022] Open
Abstract
Cells form a bipolar spindle during mitosis to ensure accurate chromosome segregation. Proper spindle architecture is established by a set of kinesin motors and microtubule-associated proteins. In most eukaryotes, kinesin-5 motors are essential for this process, and genetic or chemical inhibition of their activity leads to the emergence of monopolar spindles and cell death. However, these deficiencies can be rescued by simultaneous inactivation of kinesin-14 motors, as they counteract kinesin-5. We conducted detailed genetic analyses in fission yeast to understand the mechanisms driving spindle assembly in the absence of kinesin-5. Here, we show that deletion of the dri1 gene, which encodes a putative RNA-binding protein, can rescue temperature sensitivity caused by cut7-22, a fission yeast kinesin-5 mutant. Interestingly, kinesin-14/Klp2 levels on the spindles in the cut7 mutants were significantly reduced by the dri1 deletion, although the total levels of Klp2 and the stability of spindle microtubules remained unaffected. Moreover, RNA-binding motifs of Dri1 are essential for its cytoplasmic localization and function. We have also found that a portion of Dri1 is spatially and functionally sequestered by chaperone-based protein aggregates upon mild heat stress and limits cell division at high temperatures. We propose that Dri1 might be involved in post-transcriptional regulation through its RNA-binding ability to promote the loading of Klp2 on the spindle microtubules.
Collapse
|
6
|
Kosmas K, Filippakis H, Khabibullin D, Turkiewicz M, Lam HC, Yu J, Kedersha NL, Anderson PJ, Henske EP. TSC2 Interacts with HDLBP/Vigilin and Regulates Stress Granule Formation. Mol Cancer Res 2021; 19:1389-1397. [PMID: 33888601 DOI: 10.1158/1541-7786.mcr-20-1046] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 01/29/2021] [Accepted: 04/20/2021] [Indexed: 11/16/2022]
Abstract
Tuberous sclerosis complex (TSC) is caused by mutations of either the TSC1 or TSC2 tumor suppressor gene. TSC causes tumors of the brain, heart, kidney, skin and lymphangioleiomyomatosis (LAM). Here we report that the TSC2 protein physically binds to high-density lipoprotein binding protein (HDLBP), also called vigilin, a core stress granule (SG) protein, and that TSC2 localizes to SGs. SGs contain mRNAs and translation initiation complexes, and regulate gene expression by sequestering specific transcripts, thereby serving a cytoprotective role. TSC2 has never before been shown to localize to SGs and knocking down vigilin impacts SG translocation of TSC2. TSC2-deficient cells showed a striking increase in the number of SGs after thermal shock and arsenite treatment relative to Tsc2-expressing cells. Our findings also show that murine kidney lysates from a model of TSC have increased levels of SG components including G3BP1 and Caprin1. G3BP1 and Caprin are elevated in renal angiomyolipomas (a renal tumor common in patients with TSC) compared with control normal kidney. G3BP1 is also elevated in TSC-associated subependymal giant cell astrocytomas. We found that genetic inhibition of G3BP1 inhibits the proliferation of TSC2-deficient cells in vitro. Finally, in a mouse model of TSC, genetic inhibition of SGs suppresses cell growth, suggesting that targeting SGs may have efficacy in the therapy of TSC. IMPLICATIONS: This study demonstrates that TSC2 physically interacts with HDLBP/vigilin, a component of SGs, that TSC2 localizes to SG and that TSC2-deficient cells have more SGs, suggesting that SGs represent a novel therapeutic target in TSC.
Collapse
Affiliation(s)
- Kosmas Kosmas
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Harilaos Filippakis
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Damir Khabibullin
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Michal Turkiewicz
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Hilaire C Lam
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Jane Yu
- Division of Pulmonary, Critical Care and Sleep Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Nancy L Kedersha
- Division of Rheumatology, Immunology and Allergy, Department of Medicine, Brigham and Women' Hospital and Harvard Medical School, Boston, Massachusetts
| | - Paul J Anderson
- Division of Rheumatology, Immunology and Allergy, Department of Medicine, Brigham and Women' Hospital and Harvard Medical School, Boston, Massachusetts
| | - Elizabeth P Henske
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
| |
Collapse
|
7
|
Cabrera M, Boronat S, Marte L, Vega M, Pérez P, Ayté J, Hidalgo E. Chaperone-Facilitated Aggregation of Thermo-Sensitive Proteins Shields Them from Degradation during Heat Stress. Cell Rep 2021; 30:2430-2443.e4. [PMID: 32075773 DOI: 10.1016/j.celrep.2020.01.077] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 10/18/2019] [Accepted: 01/22/2020] [Indexed: 12/18/2022] Open
Abstract
Cells have developed protein quality-control strategies to manage the accumulation of misfolded substrates during heat stress. Using a soluble reporter of misfolding in fission yeast, Rho1.C17R-GFP, we demonstrate that upon mild heat shock, the reporter collapses in protein aggregate centers (PACs). They contain and/or require several chaperones, such as Hsp104, Hsp16, and the Hsp40/70 couple Mas5/Ssa2. Stress granules do not assemble at mild temperatures and, therefore, are not required for PAC formation; on the contrary, PACs may serve as nucleation centers for the assembly of stress granules. In contrast to the general belief, the dominant fate of these PACs is not degradation, and the aggregated reporter can be disassembled by chaperones and recovers native structure and activity. Using mass spectrometry, we show that thermo-unstable endogenous proteins form PACs as well. In conclusion, formation of PACs during heat shock is a chaperone-mediated adaptation strategy.
Collapse
Affiliation(s)
- Margarita Cabrera
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, 08003 Barcelona, Spain.
| | - Susanna Boronat
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, 08003 Barcelona, Spain
| | - Luis Marte
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, 08003 Barcelona, Spain
| | - Montserrat Vega
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, 08003 Barcelona, Spain
| | - Pilar Pérez
- Instituto de Biología Funcional y Genómica (IBFG), Consejo Superior de Investigaciones Científicas, University of Salamanca, 37007 Salamanca, Spain
| | - José Ayté
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, 08003 Barcelona, Spain
| | - Elena Hidalgo
- Oxidative Stress and Cell Cycle Group, Universitat Pompeu Fabra, C/ Dr. Aiguader 88, 08003 Barcelona, Spain.
| |
Collapse
|
8
|
Huang W, Liao CC, Han Y, Lv J, Lei M, Li Y, Lv Q, Dong D, Zhang S, Pan YH, Luo J. Co-activation of Akt, Nrf2, and NF-κB signals under UPR ER in torpid Myotis ricketti bats for survival. Commun Biol 2020; 3:658. [PMID: 33177645 PMCID: PMC7658203 DOI: 10.1038/s42003-020-01378-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 10/14/2020] [Indexed: 12/22/2022] Open
Abstract
Bats hibernate to survive stressful conditions. Examination of whole cell and mitochondrial proteomes of the liver of Myotis ricketti revealed that torpid bats had endoplasmic reticulum unfolded protein response (UPRER), global reduction in glycolysis, enhancement of lipolysis, and selective amino acid metabolism. Compared to active bats, torpid bats had higher amounts of phosphorylated serine/threonine kinase (p-Akt) and UPRER markers such as PKR-like endoplasmic reticulum kinase (PERK) and activating transcription factor 4 (ATF4). Torpid bats also had lower amounts of the complex of Kelch-like ECH-associated protein 1 (Keap1), nuclear factor erythroid 2-related factor 2 (Nrf2), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) (p65)/I-κBα. Cellular redistribution of 78 kDa glucose-regulated protein (GRP78) and reduced binding between PERK and GRP78 were also seen in torpid bats. Evidence of such was not observed in fasted, cold-treated, or normal mice. These data indicated that bats activate Akt, Nrf2, and NF-κB via the PERK-ATF4 regulatory axis against endoplasmic reticulum stresses during hibernation.
Collapse
Affiliation(s)
- Wenjie Huang
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Chen-Chung Liao
- Proteomics Research Center, National Yang-Ming University, Taipei, 11221, Taiwan
| | - Yijie Han
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Junyan Lv
- Key Laboratory of Brain Functional Genomics (Ministry of Education and Shanghai), Institute of Brain Functional Genomics, School of Life Sciences and the Collaborative Innovation Center for Brain Science, East China Normal University, Shanghai, 200062, China
| | - Ming Lei
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Yangyang Li
- Key Laboratory of Brain Functional Genomics (Ministry of Education and Shanghai), Institute of Brain Functional Genomics, School of Life Sciences and the Collaborative Innovation Center for Brain Science, East China Normal University, Shanghai, 200062, China
| | - Qingyun Lv
- Key Laboratory of Brain Functional Genomics (Ministry of Education and Shanghai), Institute of Brain Functional Genomics, School of Life Sciences and the Collaborative Innovation Center for Brain Science, East China Normal University, Shanghai, 200062, China
| | - Dong Dong
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Shuyi Zhang
- College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, 110866, China
| | - Yi-Husan Pan
- Key Laboratory of Brain Functional Genomics (Ministry of Education and Shanghai), Institute of Brain Functional Genomics, School of Life Sciences and the Collaborative Innovation Center for Brain Science, East China Normal University, Shanghai, 200062, China.
| | - Jian Luo
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China.
| |
Collapse
|
9
|
Gallardo P, Real-Calderón P, Flor-Parra I, Salas-Pino S, Daga RR. Acute Heat Stress Leads to Reversible Aggregation of Nuclear Proteins into Nucleolar Rings in Fission Yeast. Cell Rep 2020; 33:108377. [DOI: 10.1016/j.celrep.2020.108377] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 08/24/2020] [Accepted: 10/21/2020] [Indexed: 12/15/2022] Open
|
10
|
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
|
11
|
Fission Yeast Asc1 Stabilizes the Interaction between Eukaryotic Initiation Factor 3a and Rps0A/uS2 for Protein Synthesis. Mol Cell Biol 2019; 39:MCB.00161-19. [PMID: 31285271 DOI: 10.1128/mcb.00161-19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 06/29/2019] [Indexed: 12/17/2022] Open
Abstract
Aminoacyl-tRNA synthetase cofactors play important roles in coordinating aminoacylation and translation. In this study, we describe an additional function of the fission yeast aminoacyl-tRNA synthetase cofactor 1 (Asc1) in translation. We found that Asc1 directly binds and stabilizes the interaction between small ribosomal protein Rps0A/uS2 and eukaryotic initiation factor 3a (eIF3a). In the absence of Asc1, the interaction between eIF3a and Rps0A/uS2 was compromised. The interaction between Rps0A/uS2 and eIF3a mediated the 40S ribosomal subunit binding of eIF3 in 43S preinitiation complex formation to stimulate translation initiation. Keeping with this idea, in an asc1 mutant, the association of mRNA with the 40S ribosomal subunit was defective and protein synthesis was compromised. To show that Asc1 is directly involved in translation, we demonstrate that the addition of recombinant Asc1 is able to rescue the translation defect of the asc1 mutant in a cell-free system. Furthermore, this function of Asc1 is likely to be evolutionarily conserved, as a similar interaction with eIF3a and Rps0A/uS2 could be identified in the budding yeast Saccharomyces cerevisiae and human aminoacyl-tRNA synthetase cofactors. Together, these results identify a function of aminoacyl-tRNA synthetase cofactors in translation preinitiation complex formation, which adds significantly to the expanded functions associated with aminoacyl-tRNA synthetases and their cofactors.
Collapse
|
12
|
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
|
13
|
Govaere L, Morin MD, Frigault JJ, Boquel S, Cohen A, Lamarre SG, Morin PJ. Transcriptome and proteome analyses to investigate the molecular underpinnings of cold response in the Colorado potato beetle, Leptinotarsa decemlineata. Cryobiology 2019; 88:54-63. [DOI: 10.1016/j.cryobiol.2019.03.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 03/28/2019] [Accepted: 03/29/2019] [Indexed: 12/11/2022]
|
14
|
Sanchez-Marinas M, Gimenez-Zaragoza D, Martin-Ramos E, Llanes J, Cansado J, Pujol MJ, Bachs O, Aligue R. Cmk2 kinase is essential for survival in arsenite by modulating translation together with RACK1 orthologue Cpc2 in Schizosaccharomyces pombe. Free Radic Biol Med 2018; 129:116-126. [PMID: 30236788 DOI: 10.1016/j.freeradbiomed.2018.09.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 08/24/2018] [Accepted: 09/16/2018] [Indexed: 10/28/2022]
Abstract
Different studies have demonstrated multiple effects of arsenite on human physiology. However, there are many open questions concerning the mechanism of response to arsenite. Schizosaccharomyces pombe activates the Sty1 MAPK pathway as a common response to several stress conditions. The specificity of the response is due to the activation of different transcription factors and specific targets such the Cmk2 MAPKAP kinase. We have previously shown that Cmk2 is phosphorylated and activated by the MAPK Sty1 in response to oxidative stress. Here, we report that Cmk2 kinase is specifically necessary to overcome the stress caused by metalloid agents, in particular arsenite. Deletion of cmk2 increases the protein level of various components of the MAPK pathway. Moreover, Cmk2 negatively regulates translation through the Cpc2 kinase: the RACK1 orthologue in fission yeast. RACK1 is a receptor for activated C-kinase. Interestingly, RACK1 is a constituent of the eukaryotic ribosome specifically localized in the head region of the 40 S subunit. Cmk2 controls arsenite response through Cpc2 and it does so through Cpc2 ribosomal function, as observed in genetic analysis using a Cpc2 mutant unable to bind to ribosome. These findings suggest a role for Cmk2 in regulating translation and facilitating adaptation to arsenite stress in the ribosome.
Collapse
Affiliation(s)
- Marta Sanchez-Marinas
- Department of Biomedical Sciences, Facultat de Medicina, University of Barcelona, Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), CIBERONC, Barcelona 08036, Catalunya, Spain
| | - David Gimenez-Zaragoza
- Department of Biomedical Sciences, Facultat de Medicina, University of Barcelona, Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), CIBERONC, Barcelona 08036, Catalunya, Spain
| | - Edgar Martin-Ramos
- Department of Biomedical Sciences, Facultat de Medicina, University of Barcelona, Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), CIBERONC, Barcelona 08036, Catalunya, Spain
| | - Julia Llanes
- Department of Biomedical Sciences, Facultat de Medicina, University of Barcelona, Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), CIBERONC, Barcelona 08036, Catalunya, Spain
| | - José Cansado
- Yeast Physiology Group, Department of Genetics and Microbiology, Facultad de Biología, Universidad de Murcia, Murcia 30071, Spain
| | - Maria Jesús Pujol
- Department of Biomedical Sciences, Facultat de Medicina, University of Barcelona, Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), CIBERONC, Barcelona 08036, Catalunya, Spain
| | - Oriol Bachs
- Department of Biomedical Sciences, Facultat de Medicina, University of Barcelona, Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), CIBERONC, Barcelona 08036, Catalunya, Spain
| | - Rosa Aligue
- Department of Biomedical Sciences, Facultat de Medicina, University of Barcelona, Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), CIBERONC, Barcelona 08036, Catalunya, Spain.
| |
Collapse
|
15
|
Fay MM, Anderson PJ, Ivanov P. ALS/FTD-Associated C9ORF72 Repeat RNA Promotes Phase Transitions In Vitro and in Cells. Cell Rep 2018; 21:3573-3584. [PMID: 29262335 DOI: 10.1016/j.celrep.2017.11.093] [Citation(s) in RCA: 137] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 10/27/2017] [Accepted: 11/28/2017] [Indexed: 12/22/2022] Open
Abstract
Membraneless RNA granules originate via phase separation events driven by multivalent interactions. As RNA is the defining component of such granules, we examined how RNA contributes to granule assembly. Expansion of hexanucleotide GGGGCC (G4C2) repeats in the first intron of C9ORF72 is the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia (C9-ALS/FTD). We describe a biophysical phenomenon whereby G4C2 RNA (rG4C2) promotes the phase separation of RNA granule proteins in vitro and in cells. The ability of rG4C2 to promote phase separation is dependent on repeat length and RNA structure because rG4C2 must assume a G-quadruplex conformation to promote granule assembly. We demonstrate a central role for RNA in promoting phase separations and implicate rG4C2 G-quadruplex structures in the pathogenesis of C9-ALS/FTD.
Collapse
Affiliation(s)
- Marta M Fay
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Paul J Anderson
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA 02115, USA.
| | - Pavel Ivanov
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA; Department of Medicine, Harvard Medical School, Boston, MA 02115, USA; The Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA.
| |
Collapse
|
16
|
Vigilin interacts with CTCF and is involved in the maintenance of imprinting of IGF2 through a novel RNA-mediated mechanism. Int J Biol Macromol 2017; 108:515-522. [PMID: 29157910 DOI: 10.1016/j.ijbiomac.2017.11.109] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 11/15/2017] [Accepted: 11/16/2017] [Indexed: 12/16/2022]
Abstract
Accumulating evidence has revealed the imprinting of insulin-like growth factor-2 gene (IGF2) is maintained by binding of CCCTC binding factor (CTCF) to the unmethylated imprinting control region (ICR) between IGF2 and H19 genes. We have previously reported that high-density lipoprotein binding protein (HDLBP/vigilin), a multiKH-domain protein, interacts with CTCF and coexists with it at several CTCF-binding sites on the ICR to regulate general gene expression of IGF2. However, the impact of the interaction on imprinting of IGF2 remains unclear. Here, we demonstrate that cooperation of vigilin and CTCF protects IGF2 from losing of imprinting. Pull-down experiments show that KH1-7 domains of vigilin interact with zinc-finger domains of CTCF. We also display that some RNAs participate in the vigilin-CTCF interaction, one of which is H19 long noncoding RNA (lncRNA). Furthermore, we confirm that H19 lncRNA-knockdown alters the imprinting of IGF2. These data suggest that vigilin interacts with CTCF, mediated by H19 lncRNA, to keep the imprinting of IGF2.
Collapse
|
17
|
Cheng MH, Jansen RP. A jack of all trades: the RNA-binding protein vigilin. WILEY INTERDISCIPLINARY REVIEWS-RNA 2017; 8. [PMID: 28975734 DOI: 10.1002/wrna.1448] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/21/2017] [Accepted: 08/17/2017] [Indexed: 12/25/2022]
Abstract
The vigilin family of proteins is evolutionarily conserved from yeast to humans and characterized by the proteins' 14 or 15 hnRNP K homology (KH) domains, typically associated with RNA-binding. Vigilin is the largest RNA-binding protein (RBP) in the KH domain-containing family and one of the largest RBP known to date. Since its identification 30 years ago, vigilin has been shown to bind over 700 mRNAs and has been associated with cancer progression and cardiovascular disease. We provide a brief historic overview of vigilin research and outline the proteins' different functions, focusing on maintenance of genome ploidy, heterochromatin formation, RNA export, as well as regulation of translation, mRNA transport, and mRNA stability. The multitude of associated functions is reflected by the large number of identified interaction partners, ranging from tRNAs, mRNAs, ribosomes and ribosome-associated proteins, to histone methyltransferases and DNA-dependent protein kinases. Most of these partners bind to vigilin's carboxyterminus, and the two most C-terminal KH domains of the protein, KH13 and KH14, represent the main mRNA-binding interface. Since the nuclear functions of vigilins in particular are not conserved, we outline a model for the basal functions of vigilins, as well as those which were acquired during the transition from unicellular organisms to metazoa. WIREs RNA 2017, 8:e1448. doi: 10.1002/wrna.1448 For further resources related to this article, please visit the WIREs website.
Collapse
Affiliation(s)
- Matthew Hk Cheng
- International Max Planck Research School, Tuebingen, Germany.,Interfaculty Institute of Biochemistry, Tuebingen, Germany
| | | |
Collapse
|
18
|
Wang CY, Wang YT, Hsiao WY, Wang SW. Involvement of fission yeast Pdc2 in RNA degradation and P-body function. RNA (NEW YORK, N.Y.) 2017; 23:493-503. [PMID: 28031482 PMCID: PMC5340913 DOI: 10.1261/rna.059766.116] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 12/21/2016] [Indexed: 05/03/2023]
Abstract
In this study we identified Pdc2, the fission yeast ortholog of human Pat1b protein, which forms a complex with Lsm1-7 and plays a role in coupling deadenylation and decapping. The involvement of Pdc2 in RNA degradation and P-body function was also determined. We found that Pdc2 interacts with Dcp2 and is required for decapping in vivo. Although not absolutely essential for P-body assembly, overexpression of Pdc2 enhanced P-body formation even in the absence of Pdc1, the fission yeast functional homolog of human Edc4 protein, indicating that Pdc2 also plays a role in P-body formation. Intriguingly, in the absence of Pdc2, Lsm1 was found to accumulate in the nucleus, suggesting that Pdc2 shuttling between nucleus and cytoplasm plays a role in decreasing the nuclear concentration of Lsm1 to increase Lsm1 in the cytoplasm. Furthermore, unlike other components of P-bodies, the deadenylase Ccr4 did not accumulate in P-bodies in cells growing under favorable conditions and was only recruited to P-bodies after deprivation of glucose in a Pdc2-Lsm1-dependent manner, indicating a function of Pdc2 in cellular response to environmental stress. In supporting this idea, pdc2 mutants are defective in recovery from glucose starvation with a much longer time to re-enter the cell cycle. In keeping with the notion that Pat1 is a nucleocytoplasmic protein, functioning also in the nucleus, we found that Pdc2 physically and genetically interacts with the nuclear 5'-3' exonuclease Dhp1. A function of Pdc2-Lsm1, in concert with Dhp1, regulating RNA by promoting its decapping/destruction in the nucleus was suggested.
Collapse
Affiliation(s)
- Chun-Yu Wang
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli County 350, Taiwan, Republic of China
| | - Yi-Ting Wang
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli County 350, Taiwan, Republic of China
| | - Wan-Yi Hsiao
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli County 350, Taiwan, Republic of China
| | - Shao-Win Wang
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli County 350, Taiwan, Republic of China
| |
Collapse
|
19
|
Shah KH, Varia SN, Cook LA, Herman PK. A Hybrid-Body Containing Constituents of Both P-Bodies and Stress Granules Forms in Response to Hypoosmotic Stress in Saccharomyces cerevisiae. PLoS One 2016; 11:e0158776. [PMID: 27359124 PMCID: PMC4928847 DOI: 10.1371/journal.pone.0158776] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 06/21/2016] [Indexed: 01/09/2023] Open
Abstract
The cytoplasm of the eukaryotic cell is a highly compartmentalized space that contains a variety of ribonucleoprotein (RNP) granules in addition to its complement of membrane-bound organelles. These RNP granules contain specific sets of proteins and mRNAs and form in response to particular environmental and developmental stimuli. Two of the better-characterized of these RNP structures are the stress granule and Processing-body (P-body) that have been conserved from yeast to humans. In this report, we examined the cues regulating stress granule assembly and the relationship between stress granule and P-body foci. These two RNP structures are generally thought to be independent entities in eukaryotic cells. However, we found here that stress granule and P-body proteins were localized to a common or merged granule specifically in response to a hypoosmotic stress. Interestingly, these hybrid-bodies were found to be transient structures that were resolved with time into separate P-body and stress granule foci. In all, these data suggest that the identity of an RNP granule is not absolute and that it can vary depending upon the nature of the induction conditions. Since the activities of a granule are likely influenced by its protein constituency, these observations are consistent with the possibility of RNP granules having distinct functions in different cellular contexts.
Collapse
Affiliation(s)
- Khyati H. Shah
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, United States of America
| | - Sapna N. Varia
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, United States of America
| | - Laura A. Cook
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, United States of America
| | - Paul K. Herman
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio 43210, United States of America
- * E-mail:
| |
Collapse
|
20
|
The Catalytic Activity of the Ubp3 Deubiquitinating Protease Is Required for Efficient Stress Granule Assembly in Saccharomyces cerevisiae. Mol Cell Biol 2015; 36:173-83. [PMID: 26503781 DOI: 10.1128/mcb.00609-15] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 10/11/2015] [Indexed: 12/20/2022] Open
Abstract
The interior of the eukaryotic cell is a highly compartmentalized space containing both membrane-bound organelles and the recently identified nonmembranous ribonucleoprotein (RNP) granules. This study examines in Saccharomyces cerevisiae the assembly of one conserved type of the latter compartment, known as the stress granule. Stress granules form in response to particular environmental cues and have been linked to a variety of human diseases, including amyotrophic lateral sclerosis. To further our understanding of these structures, a candidate genetic screen was employed to identify regulators of stress granule assembly in quiescent cells. These studies identified a ubiquitin-specific protease, Ubp3, as having an essential role in the assembly of these RNP granules. This function was not shared by other members of the Ubp protease family and required Ubp3 catalytic activity as well as its interaction with the cofactor Bre5. Interestingly, the loss of stress granules was correlated with a decrease in the long-term survival of stationary-phase cells. This phenotype is similar to that observed in mutants defective for the formation of a related RNP complex, the Processing body. Altogether, these observations raise the interesting possibility of a general role for these types of cytoplasmic RNP granules in the survival of G0-like resting cells.
Collapse
|
21
|
Jevtov I, Zacharogianni M, van Oorschot MM, van Zadelhoff G, Aguilera-Gomez A, Vuillez I, Braakman I, Hafen E, Stocker H, Rabouille C. TORC2 mediates the heat stress response in Drosophila by promoting the formation of stress granules. J Cell Sci 2015; 128:2497-508. [PMID: 26054799 PMCID: PMC4510851 DOI: 10.1242/jcs.168724] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 06/03/2015] [Indexed: 12/29/2022] Open
Abstract
The kinase TOR is found in two complexes, TORC1, which is involved in growth control, and TORC2, whose roles are less well defined. Here, we asked whether TORC2 has a role in sustaining cellular stress. We show that TORC2 inhibition in Drosophila melanogaster leads to a reduced tolerance to heat stress, whereas sensitivity to other stresses is not affected. Accordingly, we show that upon heat stress, both in the animal and Drosophila cultured S2 cells, TORC2 is activated and is required for maintaining the level of its known target, Akt1 (also known as PKB). We show that the phosphorylation of the stress-activated protein kinases is not modulated by TORC2 nor is the heat-induced upregulation of heat-shock proteins. Instead, we show, both in vivo and in cultured cells, that TORC2 is required for the assembly of heat-induced cytoprotective ribonucleoprotein particles, the pro-survival stress granules. These granules are formed in response to protein translation inhibition imposed by heat stress that appears to be less efficient in the absence of TORC2 function. We propose that TORC2 mediates heat resistance in Drosophila by promoting the cell autonomous formation of stress granules.
Collapse
Affiliation(s)
- Irena Jevtov
- Institute of Molecular Systems Biology, ETH Zurich, Zurich 8093, Switzerland
| | | | - Marinke M van Oorschot
- Hubrecht Institute of the KNAW and UMC Utrecht, Uppsalalaan 8, Utrecht 3584 CT, Netherlands
| | - Guus van Zadelhoff
- Cellular Protein Chemistry, Utrecht University, Padualaan 8, Utrecht 3584 CH, The Netherlands
| | | | - Igor Vuillez
- Institute of Molecular Systems Biology, ETH Zurich, Zurich 8093, Switzerland
| | - Ineke Braakman
- Cellular Protein Chemistry, Utrecht University, Padualaan 8, Utrecht 3584 CH, The Netherlands
| | - Ernst Hafen
- Institute of Molecular Systems Biology, ETH Zurich, Zurich 8093, Switzerland
| | - Hugo Stocker
- Institute of Molecular Systems Biology, ETH Zurich, Zurich 8093, Switzerland
| | - Catherine Rabouille
- Hubrecht Institute of the KNAW and UMC Utrecht, Uppsalalaan 8, Utrecht 3584 CT, Netherlands Department of Cell Biology, UMC Utrecht, Heidelberglaan 100, Utrecht 3584 CX, The Netherlands
| |
Collapse
|
22
|
Yang X, Shen Y, Garre E, Hao X, Krumlinde D, Cvijović M, Arens C, Nyström T, Liu B, Sunnerhagen P. Stress granule-defective mutants deregulate stress responsive transcripts. PLoS Genet 2014; 10:e1004763. [PMID: 25375155 PMCID: PMC4222700 DOI: 10.1371/journal.pgen.1004763] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 09/18/2014] [Indexed: 01/28/2023] Open
Abstract
To reduce expression of gene products not required under stress conditions, eukaryotic cells form large and complex cytoplasmic aggregates of RNA and proteins (stress granules; SGs), where transcripts are kept translationally inert. The overall composition of SGs, as well as their assembly requirements and regulation through stress-activated signaling pathways remain largely unknown. We have performed a genome-wide screen of S. cerevisiae gene deletion mutants for defects in SG formation upon glucose starvation stress. The screen revealed numerous genes not previously implicated in SG formation. Most mutants with strong phenotypes are equally SG defective when challenged with other stresses, but a considerable fraction is stress-specific. Proteins associated with SG defects are enriched in low-complexity regions, indicating that multiple weak macromolecule interactions are responsible for the structural integrity of SGs. Certain SG-defective mutants, but not all, display an enhanced heat-induced mutation rate. We found several mutations affecting the Ran GTPase, regulating nucleocytoplasmic transport of RNA and proteins, to confer SG defects. Unexpectedly, we found stress-regulated transcripts to reach more extreme levels in mutants unable to form SGs: stress-induced mRNAs accumulate to higher levels than in the wild-type, whereas stress-repressed mRNAs are reduced further in such mutants. Our findings are consistent with the view that, not only are SGs being regulated by stress signaling pathways, but SGs also modulate the extent of stress responses. We speculate that nucleocytoplasmic shuttling of RNA-binding proteins is required for gene expression regulation during stress, and that SGs modulate this traffic. The absence of SGs thus leads the cell to excessive, and potentially deleterious, reactions to stress. When cells encounter harsh conditions, they face an energy crisis since the stress will reduce their energy production, and at the same time cause extra demands on energy expenditure. To tackle this dilemma, cells under stress form giant agglomerates of RNA and protein, called stress granules. In these, mRNA molecules are kept silent, preventing waste of energy on producing proteins not needed under these conditions. A few mRNAs, encoding proteins required for the cell to survive, stay outside of stress granules and escape this silencing. This mechanism can protect plants and microbes against cold spells or heat shocks, and human cells exposed to oxidative damage or toxic drugs. We have investigated which genes are necessary to form stress granules, and their impact on the stress response. We discovered that mutant cells unable to form stress granules overreacted to stress, in that they produced much higher levels of the induced mRNAs. We think this means that gene regulatory proteins are sequestered inside stress granules, inhibiting their action. Stress granules may thus function as moderators that dampen the stress response, safeguarding the cell against excessive reactions.
Collapse
Affiliation(s)
- Xiaoxue Yang
- School of Life Science and Engineering, Harbin Institute of Technology, Harbin, China
| | - Yi Shen
- School of Life Science and Engineering, Harbin Institute of Technology, Harbin, China
| | - Elena Garre
- Department of Chemistry and Molecular Biology, Lundberg Laboratory, University of Gothenburg, Göteborg, Sweden
| | - Xinxin Hao
- Department of Chemistry and Molecular Biology, Lundberg Laboratory, University of Gothenburg, Göteborg, Sweden
| | - Daniel Krumlinde
- Department of Chemistry and Molecular Biology, Lundberg Laboratory, University of Gothenburg, Göteborg, Sweden
| | - Marija Cvijović
- Department of Mathematical Sciences, Chalmers University of Technology, Göteborg, Sweden
- Department of Mathematical Sciences, University of Gothenburg, Göteborg, Sweden
| | - Christina Arens
- Department of Chemistry and Molecular Biology, Lundberg Laboratory, University of Gothenburg, Göteborg, Sweden
| | - Thomas Nyström
- Department of Chemistry and Molecular Biology, Lundberg Laboratory, University of Gothenburg, Göteborg, Sweden
| | - Beidong Liu
- School of Life Science and Engineering, Harbin Institute of Technology, Harbin, China
- Department of Chemistry and Molecular Biology, Lundberg Laboratory, University of Gothenburg, Göteborg, Sweden
- * E-mail: (BL); (PS)
| | - Per Sunnerhagen
- Department of Chemistry and Molecular Biology, Lundberg Laboratory, University of Gothenburg, Göteborg, Sweden
- * E-mail: (BL); (PS)
| |
Collapse
|
23
|
Zhong L, Yuan L, Rao Y, Li Z, Gu Q, Long Y, Zhang X, Cui Z, Xu Y, Dai H. Investigation of effect of 17α-ethinylestradiol on vigilin expression using an isolated recombinant antibody. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2014; 156:1-9. [PMID: 25112681 DOI: 10.1016/j.aquatox.2014.07.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 07/18/2014] [Accepted: 07/19/2014] [Indexed: 06/03/2023]
Abstract
Vigilin, a highly conserved protein from yeast to mammals, is a multifunctional protein in eukaryotic organisms. One biological function of vigilin is to stabilize the expression level of vitellogenin (VTG). This study aimed to develop vigilin as a new estrogen-inducible biomarker that correlates with the widely applied estrogen-inducible biomarker VTG and expand the ability to detect it in various species. Here, a recombinant monoclonal antibody with high specificity against the conserved C-terminal region of vigilin from zebrafish (Danio rerio) was successfully isolated from a phage display antibody library and found to recognize vigilin proteins from multiple vertebrate species. The effect of 17α-ethinylestradiol (EE2) on vigilin expression in the liver of zebrafish and juvenile crucian carp (Carassius auratus) was investigated. Although vigilin mRNA was expressed in all tissues analyzed from male zebrafish, vigilin protein was detected exclusively in the testis of male zebrafish, as well as the liver of female zebrafish and juvenile crucian carp at a lower level without exposure to EE2. Significant induction of vigilin mRNA by exposure to EE2 was observed in the liver and testis of male zebrafish, even at a low dose of 6.25 ng/L (21.09 pmol/L). In Hela cells, the expression of vigilin coincided with high protein synthesis activity but not dose-dependently by EE2 exposure. Therefore, the recombinant antibody may be used as a detection tool to screen for mammalian cell lines or organs with estrogen-inducible expression of vigilin.
Collapse
Affiliation(s)
- Liqiao Zhong
- State Key Laboratory of Fresh water Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 7 Southern East Lake Road, Wuhan 430072, PR China
| | - Li Yuan
- State Key Laboratory of Fresh water Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 7 Southern East Lake Road, Wuhan 430072, PR China
| | - Yu Rao
- State Key Laboratory of Fresh water Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 7 Southern East Lake Road, Wuhan 430072, PR China
| | - Zhouquan Li
- State Key Laboratory of Fresh water Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 7 Southern East Lake Road, Wuhan 430072, PR China; University of Chinese Academy of Sciences, Yuquan Road 19A, Beijing 100039, PR China
| | - Qilin Gu
- State Key Laboratory of Fresh water Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 7 Southern East Lake Road, Wuhan 430072, PR China; University of Chinese Academy of Sciences, Yuquan Road 19A, Beijing 100039, PR China
| | - Yong Long
- State Key Laboratory of Fresh water Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 7 Southern East Lake Road, Wuhan 430072, PR China
| | - Xiaohua Zhang
- State Key Laboratory of Fresh water Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 7 Southern East Lake Road, Wuhan 430072, PR China.
| | - Zongbin Cui
- State Key Laboratory of Fresh water Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 7 Southern East Lake Road, Wuhan 430072, PR China
| | - Ying Xu
- State Key Laboratory of Fresh water Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 7 Southern East Lake Road, Wuhan 430072, PR China
| | - Heping Dai
- State Key Laboratory of Fresh water Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, 7 Southern East Lake Road, Wuhan 430072, PR China.
| |
Collapse
|
24
|
Laval J, Touhami J, Herzenberg LA, Conrad C, Taylor N, Battini JL, Sitbon M, Tirouvanziam R. Metabolic adaptation of neutrophils in cystic fibrosis airways involves distinct shifts in nutrient transporter expression. THE JOURNAL OF IMMUNOLOGY 2013; 190:6043-50. [PMID: 23690474 DOI: 10.4049/jimmunol.1201755] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Inflammatory conditions can profoundly alter human neutrophils, a leukocyte subset generally viewed as terminally differentiated and catabolic. In cystic fibrosis (CF) patients, neutrophils recruited to CF airways show active exocytosis and sustained phosphorylation of prosurvival, metabolic pathways. Because the CF airway lumen is also characterized by high levels of free glucose and amino acids, we compared surface expression of Glut1 (glucose) and ASCT2 (neutral amino acids) transporters, as well as that of PiT1 and PiT2 (inorganic phosphate transporters), in blood and airway neutrophils, using specific retroviral envelope-derived ligands. Neither nutrient transporter expression nor glucose uptake was altered on blood neutrophils from CF patients compared with healthy controls. Notably, however, airway neutrophils of CF patients had higher levels of PiT1 and Glut1 and increased glucose uptake compared with their blood counterparts. Based on primary granule exocytosis and scatter profiles, CF airway neutrophils could be divided into two subsets, with one of the subsets characterized by more salient increases in Glut1, ASCT2, PiT1, and PiT2 expression. Moreover, in vitro exocytosis assays of blood neutrophils suggest that surface nutrient transporter expression is not directly associated with primary (or secondary) granule exocytosis. Although expression of nutrient transporters on CF blood or airway neutrophils was not altered by genotype, age, gender, or Pseudomonas aeruginosa infection, oral steroid treatment decreased Glut1 and PiT2 levels in blood neutrophils. Thus, neutrophils recruited from blood into the CF airway lumen display augmented cell surface nutrient transporter expression and glucose uptake, consistent with metabolic adaptation.
Collapse
Affiliation(s)
- Julie Laval
- Department of Pediatrics, Emory University, Atlanta, GA 30322, USA
| | | | | | | | | | | | | | | |
Collapse
|
25
|
Abstract
P bodies are cytoplasmic RNA granules containing the Dcp1-Dcp2 decapping enzymes where mRNA decay can occur. Here, we describe the characterization of P bodies in the fission yeast Schizosaccharomyces pombe. Most information on the property and function of P bodies stems from studies in the distantly related budding yeast Saccharomyces cerevisiae, and Edc3 was identified as a scaffold protein required for P-body assembly. However, we found that, unlike in S. cerevisiae, fission yeast Edc3 was dispensable for P-body formation. Pdc1, a novel partner of the fission yeast decapping enzyme, with a limited similarity to plant Edc4/Varicose that is required for the assembly of P bodies, was identified (tandem affinity purification-matrix-assisted laser desorption ionization tandem mass spectrometry [TAP-MALDI MS/MS]). Pdc1 interacts with Dcp2 through its C terminus and contains a coiled-coil region for self-interaction to mediate P-body formation. In line with the model that Pdc1 cross-bridges different proteins, additional interactions can be demonstrated with components such as Edc3 and Ste13. Although Pdc1 is not required for the interaction between Dcp1 and Dcp2, our data suggest that Pdc1 acts as a functional homologue of Edc4, a third component of the decapping enzymes that is thought to be absent from fungi. Together, these results highlight the diverse P-body protein compositions between different species and might help to provide insight into their evolutionary paths.
Collapse
|
26
|
Wang CY, Wen WL, Nilsson D, Sunnerhagen P, Chang TH, Wang SW. Analysis of stress granule assembly in Schizosaccharomyces pombe. RNA (NEW YORK, N.Y.) 2012; 18:694-703. [PMID: 22328580 PMCID: PMC3312557 DOI: 10.1261/rna.030270.111] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 12/11/2011] [Indexed: 05/20/2023]
Abstract
Stress granules (SGs) are cytoplasmic aggregates of RNA and proteins in eukaryotic cells that are rapidly induced in response to environmental stress, but are not seen in cells growing under favorable conditions. SGs have been primarily studied in mammalian cells. The existence of SGs in the fission yeast and the distantly related budding yeast was demonstrated only recently. In both species, they contain many orthologs of the proteins seen in mammalian SGs. In this study, we have characterized these proteins and determined their involvement in the assembly of fission yeast SGs, in particular, the homolog of human G3BP proteins. G3BP interacts with the deubiquitinating protease USP10 and plays an important role in the assembly of SGs. We have also identified Ubp3, an ortholog of USP10, as an interaction partner of the fission yeast G3BP-like protein Nxt3 and required for its stability. Under thermal stress, like their human orthologs, both Nxt3 and Ubp3 rapidly relocalize to cytoplasmic foci that contain the SG marker poly(A)-binding protein Pabp. However, in contrast to G3BP1 and USP10, neither deletion nor overexpression of nxt3(+) or ubp3(+) affected the assembly of fission yeast SGs as judged by the relocalization of Pabp. Similar results were observed in mutants defective in orthologs of SG components that are known to affect SG assembly in human and in budding yeast, such as ataxia-2 and TIA-like proteins. Together, our data indicate that despite similar protein compositions, the underlying molecular mechanisms for the assembly of SGs could be distinct between species.
Collapse
Affiliation(s)
- Chun-Yu Wang
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Zhunan Town, Miaoli County 350, Taiwan
| | - Wei-Ling Wen
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Zhunan Town, Miaoli County 350, Taiwan
| | - Daniel Nilsson
- Department of Cell and Molecular Biology, Lundberg Laboratory, University of Gothenburg, S-405 30 Göteborg, Sweden
| | - Per Sunnerhagen
- Department of Cell and Molecular Biology, Lundberg Laboratory, University of Gothenburg, S-405 30 Göteborg, Sweden
| | - Tien-Hsien Chang
- Genomics Research Center, Academia Sinica, Nankang, Taipei 11529, Taiwan
| | - Shao-Win Wang
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Zhunan Town, Miaoli County 350, Taiwan
- Corresponding author.E-mail .
| |
Collapse
|
27
|
Satoh R, Tanaka A, Kita A, Morita T, Matsumura Y, Umeda N, Takada M, Hayashi S, Tani T, Shinmyozu K, Sugiura R. Role of the RNA-binding protein Nrd1 in stress granule formation and its implication in the stress response in fission yeast. PLoS One 2012; 7:e29683. [PMID: 22276125 PMCID: PMC3261880 DOI: 10.1371/journal.pone.0029683] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Accepted: 12/02/2011] [Indexed: 01/20/2023] Open
Abstract
We have previously identified the RNA recognition motif (RRM)-type RNA-binding protein Nrd1 as an important regulator of the posttranscriptional expression of myosin in fission yeast. Pmk1 MAPK-dependent phosphorylation negatively regulates the RNA-binding activity of Nrd1. Here, we report the role of Nrd1 in stress-induced RNA granules. Nrd1 can localize to poly(A)-binding protein (Pabp)-positive RNA granules in response to various stress stimuli, including heat shock, arsenite treatment, and oxidative stress. Interestingly, compared with the unphosphorylatable Nrd1, Nrd1DD (phosphorylation-mimic version of Nrd1) translocates more quickly from the cytoplasm to the stress granules in response to various stimuli; this suggests that the phosphorylation of Nrd1 by MAPK enhances its localization to stress-induced cytoplasmic granules. Nrd1 binds to Cpc2 (fission yeast RACK) in a phosphorylation-dependent manner and deletion of Cpc2 affects the formation of Nrd1-positive granules upon arsenite treatment. Moreover, the depletion of Nrd1 leads to a delay in Pabp-positive RNA granule formation, and overexpression of Nrd1 results in an increased size and number of Pabp-positive granules. Interestingly, Nrd1 deletion induced resistance to sustained stresses and enhanced sensitivity to transient stresses. In conclusion, our results indicate that Nrd1 plays a role in stress-induced granule formation, which affects stress resistance in fission yeast.
Collapse
Affiliation(s)
- Ryosuke Satoh
- Laboratory of Molecular Pharmacogenomics, School of Pharmaceutical Sciences, Kinki University, Osaka, Japan
- Japan Society for the Promotion of Science, Tokyo, Japan
| | - Akitomo Tanaka
- Laboratory of Molecular Pharmacogenomics, School of Pharmaceutical Sciences, Kinki University, Osaka, Japan
| | - Ayako Kita
- Laboratory of Molecular Pharmacogenomics, School of Pharmaceutical Sciences, Kinki University, Osaka, Japan
| | - Takahiro Morita
- Laboratory of Molecular Pharmacogenomics, School of Pharmaceutical Sciences, Kinki University, Osaka, Japan
| | - Yasuhiro Matsumura
- Laboratory of Molecular Pharmacogenomics, School of Pharmaceutical Sciences, Kinki University, Osaka, Japan
| | - Nanae Umeda
- Laboratory of Molecular Pharmacogenomics, School of Pharmaceutical Sciences, Kinki University, Osaka, Japan
| | - Makoto Takada
- Laboratory of Molecular Pharmacogenomics, School of Pharmaceutical Sciences, Kinki University, Osaka, Japan
| | - Sachiko Hayashi
- Department of Biological Sciences, Graduate School of Science and Technology, Kumamoto University, Kumamoto, Japan
| | - Tokio Tani
- Department of Biological Sciences, Graduate School of Science and Technology, Kumamoto University, Kumamoto, Japan
| | - Kaori Shinmyozu
- Proteomics Support Unit, RIKEN Center for Developmental Biology, Hyogo, Japan
| | - Reiko Sugiura
- Laboratory of Molecular Pharmacogenomics, School of Pharmaceutical Sciences, Kinki University, Osaka, Japan
- * E-mail:
| |
Collapse
|
28
|
Morita T, Satoh R, Umeda N, Kita A, Sugiura R. The stress granule protein Vgl1 and poly(A)-binding protein Pab1 are required for doxorubicin resistance in the fission yeast Schizosaccharomyces pombe. Biochem Biophys Res Commun 2011; 417:399-403. [PMID: 22172946 DOI: 10.1016/j.bbrc.2011.11.127] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2011] [Accepted: 11/29/2011] [Indexed: 10/14/2022]
Abstract
Doxorubicin is an anthracycline antibiotic widely used for chemotherapy. Although doxorubicin is effective in the treatment of several cancers, including solid tumors and leukemias, the basis of its mechanism of action is not completely understood. Here, we describe the effects of doxorubicin and its relationship with stress granules formation in the fission yeast, Schizosaccharomyces pombe. We show that disruption of genes encoding the components of stress granules, including vgl1(+), which encodes a multi-KH type RNA-binding protein, and pab1(+), which encodes a poly(A)-binding protein, resulted in greater sensitivity to doxorubicin than seen in wild-type cells. Disruption of the vgl1(+) and pab1(+) genes did not confer sensitivity to other anti-cancer drugs such as cisplatin, 5-fluorouracil, and paclitaxel. We also showed that doxorubicin treatment promoted stress granule formation when combined with heat shock. Notably, doxorubicin treatment did not induce hyperphosphorylation of eIF2α, suggesting that doxorubicin is involved in stress granule assembly independent of eIF2α phosphorylation. Our results demonstrate the usefulness of fission yeast for elucidating the molecular targets of doxorubicin toxicity and suggest a novel drug-resistance mechanism involving stress granule assembly.
Collapse
Affiliation(s)
- Takahiro Morita
- Laboratory of Molecular Pharmacogenomics, School of Pharmaceutical Sciences, Kinki University, Higashi-Osaka, Japan
| | | | | | | | | |
Collapse
|
29
|
Batlle M, Marsellach FX, Huertas D, Azorín F. Drosophila vigilin, DDP1, localises to the cytoplasm and associates to the rough endoplasmic reticulum. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2011; 1809:46-55. [DOI: 10.1016/j.bbagrm.2010.10.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 10/06/2010] [Accepted: 10/19/2010] [Indexed: 01/22/2023]
|