1
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Tammaro A, Daniels EG, Hu IM, ‘t Hart KC, Reid K, Juni RP, Butter LM, Vasam G, Kamble R, Jongejan A, Aviv RI, Roelofs JJ, Aronica E, Boon RA, Menzies KJ, Houtkooper RH, Janssens GE. HDAC1/2 inhibitor therapy improves multiple organ systems in aged mice. iScience 2024; 27:108681. [PMID: 38269100 PMCID: PMC10805681 DOI: 10.1016/j.isci.2023.108681] [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: 08/19/2023] [Revised: 09/25/2023] [Accepted: 12/05/2023] [Indexed: 01/26/2024] Open
Abstract
Aging increases the risk of age-related diseases, imposing substantial healthcare and personal costs. Targeting fundamental aging mechanisms pharmacologically can promote healthy aging and reduce this disease susceptibility. In this work, we employed transcriptome-based drug screening to identify compounds emulating transcriptional signatures of long-lived genetic interventions. We discovered compound 60 (Cmpd60), a selective histone deacetylase 1 and 2 (HDAC1/2) inhibitor, mimicking diverse longevity interventions. In extensive molecular, phenotypic, and bioinformatic assessments using various cell and aged mouse models, we found Cmpd60 treatment to improve age-related phenotypes in multiple organs. Cmpd60 reduces renal epithelial-mesenchymal transition and fibrosis in kidney, diminishes dementia-related gene expression in brain, and enhances cardiac contractility and relaxation for the heart. In sum, our two-week HDAC1/2 inhibitor treatment in aged mice establishes a multi-tissue, healthy aging intervention in mammals, holding promise for therapeutic translation to promote healthy aging in humans.
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Affiliation(s)
- Alessandra Tammaro
- Amsterdam UMC location University of Amsterdam, Department of Pathology, Amsterdam Infection & Immunity, Amsterdam, the Netherlands
| | - Eileen G. Daniels
- Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
- Amsterdam Gastroenterology, Endocrinology and Metabolism Institute, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Iman M. Hu
- Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
- Amsterdam Gastroenterology, Endocrinology and Metabolism Institute, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Kelly C. ‘t Hart
- Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
- Amsterdam Gastroenterology, Endocrinology and Metabolism Institute, Amsterdam University Medical Centers, Amsterdam, the Netherlands
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Kim Reid
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
| | - Rio P. Juni
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Loes M. Butter
- Amsterdam UMC location University of Amsterdam, Department of Pathology, Amsterdam Infection & Immunity, Amsterdam, the Netherlands
| | - Goutham Vasam
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
| | - Rashmi Kamble
- Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
| | - Aldo Jongejan
- Deptartment of Epidemiology & Data Science (EDS), Bioinformatics Laboratory, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Richard I. Aviv
- Department of Medical Imaging, The Ottawa Hospital, 1053 Carling Ave, Ottawa, ON K1Y 4E9, Canada
- Department of Radiology, University of Ottawa, Ottawa, ON, Canada
| | - Joris J.T.H. Roelofs
- Amsterdam UMC location University of Amsterdam, Department of Pathology, Amsterdam Infection & Immunity, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Microcirculation, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, the Netherlands
| | - Reinier A. Boon
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Keir J. Menzies
- Department of Biology, University of Ottawa, Ottawa, ON, Canada
| | - Riekelt H. Houtkooper
- Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
- Amsterdam Gastroenterology, Endocrinology and Metabolism Institute, Amsterdam University Medical Centers, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Georges E. Janssens
- Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
- Amsterdam Gastroenterology, Endocrinology and Metabolism Institute, Amsterdam University Medical Centers, Amsterdam, the Netherlands
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2
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Castelli LM, Benson BC, Huang WP, Lin YH, Hautbergue GM. RNA Helicases in Microsatellite Repeat Expansion Disorders and Neurodegeneration. Front Genet 2022; 13:886563. [PMID: 35646086 PMCID: PMC9133428 DOI: 10.3389/fgene.2022.886563] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/25/2022] [Indexed: 11/17/2022] Open
Abstract
Short repeated sequences of 3-6 nucleotides are causing a growing number of over 50 microsatellite expansion disorders, which mainly present with neurodegenerative features. Although considered rare diseases in relation to the relatively low number of cases, these primarily adult-onset conditions, often debilitating and fatal in absence of a cure, collectively pose a large burden on healthcare systems in an ageing world population. The pathological mechanisms driving disease onset are complex implicating several non-exclusive mechanisms of neuronal injury linked to RNA and protein toxic gain- and loss- of functions. Adding to the complexity of pathogenesis, microsatellite repeat expansions are polymorphic and found in coding as well as in non-coding regions of genes. They form secondary and tertiary structures involving G-quadruplexes and atypical helices in repeated GC-rich sequences. Unwinding of these structures by RNA helicases plays multiple roles in the expression of genes including repeat-associated non-AUG (RAN) translation of polymeric-repeat proteins with aggregating and cytotoxic properties. Here, we will briefly review the pathogenic mechanisms mediated by microsatellite repeat expansions prior to focus on the RNA helicases eIF4A, DDX3X and DHX36 which act as modifiers of RAN translation in C9ORF72-linked amyotrophic lateral sclerosis/frontotemporal dementia (C9ORF72-ALS/FTD) and Fragile X-associated tremor/ataxia syndrome (FXTAS). We will further review the RNA helicases DDX5/17, DHX9, Dicer and UPF1 which play additional roles in the dysregulation of RNA metabolism in repeat expansion disorders. In addition, we will contrast these with the roles of other RNA helicases such as DDX19/20, senataxin and others which have been associated with neurodegeneration independently of microsatellite repeat expansions. Finally, we will discuss the challenges and potential opportunities that are associated with the targeting of RNA helicases for the development of future therapeutic approaches.
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Affiliation(s)
- Lydia M Castelli
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Bridget C Benson
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Wan-Ping Huang
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Ya-Hui Lin
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom
| | - Guillaume M Hautbergue
- Sheffield Institute for Translational Neuroscience (SITraN), Department of Neuroscience, University of Sheffield, Sheffield, United Kingdom.,Neuroscience Institute, University of Sheffield, Sheffield, United Kingdom.,Healthy Lifespan Institute (HELSI), University of Sheffield, Sheffield, United Kingdom
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3
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Simone R, Javad F, Emmett W, Wilkins OG, Almeida FL, Barahona-Torres N, Zareba-Paslawska J, Ehteramyan M, Zuccotti P, Modelska A, Siva K, Virdi GS, Mitchell JS, Harley J, Kay VA, Hondhamuni G, Trabzuni D, Ryten M, Wray S, Preza E, Kia DA, Pittman A, Ferrari R, Manzoni C, Lees A, Hardy JA, Denti MA, Quattrone A, Patani R, Svenningsson P, Warner TT, Plagnol V, Ule J, de Silva R. MIR-NATs repress MAPT translation and aid proteostasis in neurodegeneration. Nature 2021; 594:117-123. [PMID: 34012113 PMCID: PMC7610982 DOI: 10.1038/s41586-021-03556-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 04/15/2021] [Indexed: 12/22/2022]
Abstract
The human genome expresses thousands of natural antisense transcripts (NAT) that can regulate epigenetic state, transcription, RNA stability or translation of their overlapping genes1,2. Here we describe MAPT-AS1, a brain-enriched NAT that is conserved in primates and contains an embedded mammalian-wide interspersed repeat (MIR), which represses tau translation by competing for ribosomal RNA pairing with the MAPT mRNA internal ribosome entry site3. MAPT encodes tau, a neuronal intrinsically disordered protein (IDP) that stabilizes axonal microtubules. Hyperphosphorylated, aggregation-prone tau forms the hallmark inclusions of tauopathies4. Mutations in MAPT cause familial frontotemporal dementia, and common variations forming the MAPT H1 haplotype are a significant risk factor in many tauopathies5 and Parkinson's disease. Notably, expression of MAPT-AS1 or minimal essential sequences from MAPT-AS1 (including MIR) reduces-whereas silencing MAPT-AS1 expression increases-neuronal tau levels, and correlate with tau pathology in human brain. Moreover, we identified many additional NATs with embedded MIRs (MIR-NATs), which are overrepresented at coding genes linked to neurodegeneration and/or encoding IDPs, and confirmed MIR-NAT-mediated translational control of one such gene, PLCG1. These results demonstrate a key role for MAPT-AS1 in tauopathies and reveal a potentially broad contribution of MIR-NATs to the tightly controlled translation of IDPs6, with particular relevance for proteostasis in neurodegeneration.
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Affiliation(s)
- Roberto Simone
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK.
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK.
| | - Faiza Javad
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
| | - Warren Emmett
- UCL Genetics Institute, London, UK
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
- Inivata Ltd, Babraham, UK
| | - Oscar G Wilkins
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
- The Francis Crick Institute, London, UK
| | - Filipa Lourenço Almeida
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
| | - Natalia Barahona-Torres
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, UK
| | | | - Mazdak Ehteramyan
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
| | - Paola Zuccotti
- Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Angelika Modelska
- Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Kavitha Siva
- Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Gurvir S Virdi
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
- The Francis Crick Institute, London, UK
| | - Jamie S Mitchell
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
- The Francis Crick Institute, London, UK
| | - Jasmine Harley
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
- The Francis Crick Institute, London, UK
| | - Victoria A Kay
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
| | - Geshanthi Hondhamuni
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
| | - Daniah Trabzuni
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, UK
| | - Mina Ryten
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, UK
| | - Selina Wray
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, UK
| | - Elisavet Preza
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, UK
| | - Demis A Kia
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
| | - Alan Pittman
- Genetics Research Centre, Molecular and Clinical Sciences, St George's University of London, London, UK
| | - Raffaele Ferrari
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, UK
| | - Claudia Manzoni
- UCL School of Pharmacy, Department of Pharmacology, London, UK
| | - Andrew Lees
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
| | - John A Hardy
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, UK
- UK Dementia Research Institute, UCL, London, UK
- Institute for Advanced Study, The Hong Kong University of Science and Technology, Hong Kong, SAR, China
| | - Michela A Denti
- Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Alessandro Quattrone
- Department of Cellular, Computational and Integrative Biology (CIBIO), Trento, Italy
| | - Rickie Patani
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
- The Francis Crick Institute, London, UK
| | - Per Svenningsson
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Thomas T Warner
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK
| | | | - Jernej Ule
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, UK
- The Francis Crick Institute, London, UK
- National Institute of Chemistry, Ljubljana, Slovenia
| | - Rohan de Silva
- Reta Lila Weston Institute, UCL Queen Square Institute of Neurology, London, UK.
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London, UK.
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4
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GIM SA, PARK DJ, KANG JB, SHAH FA, KOH PO. Identification of regulated proteins by resveratrol in glutamate-induced cortical injury of newborn rats. J Vet Med Sci 2021; 83:724-733. [PMID: 33716268 PMCID: PMC8111349 DOI: 10.1292/jvms.21-0013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 02/15/2021] [Indexed: 11/22/2022] Open
Abstract
Glutamate induces neuronal damage by generating oxidative stress and neurotoxicities. The neurological damage caused by glutamate is more severe during brain development in newborns than in adults. Resveratrol is naturally present in a variety of fruits and medicinal plants and exerts a neuroprotective effect against brain damage. The goal of this study was to evaluate the neuroprotective effects of resveratrol and to identify changed proteins in response to resveratrol treatment during glutamate-induced neonatal cortical damage. Sprague-Dawley rat pups (7 days old) were randomly divided into vehicle, resveratrol, glutamate, and glutamate and resveratrol groups. The animals were intraperitoneally injected with glutamate (10 mg/kg) and/or resveratrol (20 mg/kg) and their brain tissue was collected 4 hr after drug administration. Glutamate exposure caused severe histopathological changes, while resveratrol attenuated this damage. We identified regulated proteins by resveratrol in glutamate-induced cortical damaged tissue using two-dimensional gel electrophoresis and mass spectrometry. Among identified proteins, we focused on eukaryotic initiation factor 4A2, γ-enolase, protein phosphatase 2A subunit B, and isocitrate dehydrogenase. These proteins decreased in the glutamate-treated group, whereas the combination treatment of glutamate and resveratrol attenuated these protein reductions. These proteins are anti-oxidant proteins and anti-apoptotic proteins. These results suggest that glutamate induces brain cortical damage in newborns; resveratrol exerts a neuroprotective effect by controlling expression of various proteins with anti-oxidant and anti-apoptotic functions.
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Affiliation(s)
- Sang-A GIM
- Department of Anatomy, College of Veterinary Medicine,
Research Institute of Life Science, Gyeongsang National University, 501 Jinjudaero, Jinju,
52828, South Korea
| | - Dong-Ju PARK
- Department of Anatomy, College of Veterinary Medicine,
Research Institute of Life Science, Gyeongsang National University, 501 Jinjudaero, Jinju,
52828, South Korea
| | - Ju-Bin KANG
- Department of Anatomy, College of Veterinary Medicine,
Research Institute of Life Science, Gyeongsang National University, 501 Jinjudaero, Jinju,
52828, South Korea
| | - Fawad-Ali SHAH
- Department of Anatomy, College of Veterinary Medicine,
Research Institute of Life Science, Gyeongsang National University, 501 Jinjudaero, Jinju,
52828, South Korea
- Current affiliation: Riphah Institute of Pharmaceutical
Sciences, Riphah International University, near Hajj Complex, I-14, Islamabad, Islamabad
Capital Territory 46000, Pakistan
| | - Phil-Ok KOH
- Department of Anatomy, College of Veterinary Medicine,
Research Institute of Life Science, Gyeongsang National University, 501 Jinjudaero, Jinju,
52828, South Korea
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5
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Low-molecular-weight chondroitin sulfate attenuated injury by inhibiting oxidative stress in amyloid β-treated SH-SY5Y cells. Neuroreport 2019; 29:1174-1179. [PMID: 29985831 DOI: 10.1097/wnr.0000000000001092] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The neurotoxicity of aggregated amyloid β (Aβ) has been implicated as a critical cause in the pathogenesis of Alzheimer's disease. In a previous work, we have shown that low-molecular-weight chondroitin sulfate (LMWCS), a derivative of chondroitin sulfate, protected the SH-SY5Y neuroblastoma cells from Aβ25-35-induced neurotoxicity, decreased intracellular reactive oxygen species level and inhibited the cell apoptosis. However, the underlying mechanism of the antioxidative effect of LMWCS in the SH-SY5Y cells has not been well explored. In the present study, the SH-SY5Y cells were cultured and exposed to 30 μM Aβ25-35 in the absence or presence of LMWCS (50, 100 and 200 μg/ml). Results indicate that incubation of cells with LMWCS before Aβ25-35 exposure increased superoxide dismutase, glutathione peroxidase and Na/K-ATPase activities and decreased the malondialdehyde content. In addition, LMWCS inhibited the imbalance of Bcl-2 and Bax and decreased caspase-3 and caspase-9 expressions. LMWCS antagonizes Aβ25-35-induced neurotoxicity by attenuating oxidative stress, and our results suggest that LMWCS might be used as a potential compound for Alzheimer's disease prevention.
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6
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Cramer Z, Sadek J, Vazquez GG, Di Marco S, Pause A, Pelletier J, Gallouzi IE. eIF4A inhibition prevents the onset of cytokine-induced muscle wasting by blocking the STAT3 and iNOS pathways. Sci Rep 2018; 8:8414. [PMID: 29849089 PMCID: PMC5976662 DOI: 10.1038/s41598-018-26625-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 05/15/2018] [Indexed: 02/07/2023] Open
Abstract
Cachexia is a deadly muscle wasting syndrome that arises under conditions linked to chronic inflammation, such as cancer. Cytokines, including interferon γ (IFNγ), tumor necrosis factor α (TNFα) and interleukin-6 (IL-6), and their downstream effectors such as Signal Transducer and Activator of Transcription 3 (STAT3), have been shown to play a prominent role in muscle wasting. Previously, we demonstrated that Pateamine A (PatA), a compound that targets eukaryotic initiation factor 4A (eIF4A), could prevent muscle wasting by modulating the translation of the inducible Nitric Oxide Synthase (iNOS) mRNA. Here we show that hippuristanol, a compound that impedes eIF4A in a manner distinct from PatA, similarly inhibits the iNOS/NO pathway and cytokine-induced muscle wasting. Furthermore, we show that hippuristanol perturbs the activation of the STAT3 pathway and expression of STAT3-gene targets such as IL-6. The decreased activation of STAT3, which resulted from a decrease in STAT3 protein expression, was due to the inhibition of STAT3 translation as there were no changes in STAT3 mRNA levels. These effects are likely dependent on the inhibition of eIF4A activity since we observed similar results using PatA. Our results identify the inhibition of eIF4A-responsive transcripts, such as STAT3, as a viable approach to alleviate cachexia.
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Affiliation(s)
- Zvi Cramer
- McGill University, Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, Montreal, Quebec, Canada
| | - Jason Sadek
- McGill University, Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, Montreal, Quebec, Canada
| | - Gabriela Galicia Vazquez
- McGill University, Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, Montreal, Quebec, Canada
| | - Sergio Di Marco
- McGill University, Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, Montreal, Quebec, Canada
| | - Arnim Pause
- McGill University, Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, Montreal, Quebec, Canada
| | - Jerry Pelletier
- McGill University, Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, Montreal, Quebec, Canada
| | - Imed-Eddine Gallouzi
- McGill University, Department of Biochemistry, Rosalind and Morris Goodman Cancer Centre, Montreal, Quebec, Canada. .,Hamad Bin Khalifa University (HBKU), College of Science and Engineering, Life Sciences Division, Education City, Doha, PB, 5825, Qatar.
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7
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Li Z, Zhang Y, Liu Y, Liu Y, Li Y. Identification of key genes in Gram‑positive and Gram‑negative sepsis using stochastic perturbation. Mol Med Rep 2017; 16:3133-3146. [PMID: 28714002 PMCID: PMC5548058 DOI: 10.3892/mmr.2017.7013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 05/17/2017] [Indexed: 01/01/2023] Open
Abstract
Sepsis is an inflammatory response to pathogens (such as Gram-positive and Gram-negative bacteria), which has high morbidity and mortality in critically ill patients. The present study aimed to identify the key genes in Gram-positive and Gram-negative sepsis. GSE6535 was downloaded from Gene Expression Omnibus, containing 17 control samples, 18 Gram-positive samples and 25 Gram-negative samples. Subsequently, the limma package in R was used to screen the differentially expressed genes (DEGs). Hierarchical clustering was conducted for the specific DEGs in Gram-negative and Gram-negative samples using cluster software and the TreeView software. To analyze the correlation of samples at the gene level, a similarity network was constructed using Cytoscape software. Functional and pathway enrichment analyses were conducted for the DEGs using DAVID. Finally, stochastic perturbation was used to determine the significantly differential functions between Gram-positive and Gram-negative samples. A total of 340 and 485 DEGs were obtained in Gram-positive and Gram-negative samples, respectively. Hierarchical clustering revealed that there were significant differences between control and sepsis samples. In Gram-positive and Gram-negative samples, myeloid cell leukemia sequence 1 was associated with apoptosis and programmed cell death. Additionally, NADH:ubiquinone oxidoreductase subunit S4 was associated with mitochondrial respiratory chain complex I assembly. Stochastic perturbation analysis revealed that NADH:ubiquinone oxidoreductase subunit B2 (NDUFB2), NDUFB8 and ubiquinol-cytochrome c reductase hinge protein (UQCRH) were associated with cellular respiration in Gram-negative samples, whereas large tumor suppressor kinase 2 (LATS2) was associated with G1/S transition of the mitotic cell cycle in Gram-positive samples. NDUFB2, NDUFB8 and UQCRH may be biomarkers for Gram-negative sepsis, whereas LATS2 may be a biomarker for Gram-positive sepsis. These findings may promote the therapies of sepsis caused by Gram-positive and Gram-negative bacteria.
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Affiliation(s)
- Zhenliang Li
- Intensive Care Unit, Pinggu Hospital Affiliated to Capital Medical University, Beijing 101200, P.R. China
| | - Ying Zhang
- Department of Infection Diseases, Beijing Pinggu Hospital of Traditional Chinese Medicine, Beijing 101200, P.R. China
| | - Yaling Liu
- Intensive Care Unit, Pinggu Hospital Affiliated to Capital Medical University, Beijing 101200, P.R. China
| | - Yanchun Liu
- Intensive Care Unit, Pinggu Hospital Affiliated to Capital Medical University, Beijing 101200, P.R. China
| | - Youyi Li
- Intensive Care Unit, Pinggu Hospital Affiliated to Capital Medical University, Beijing 101200, P.R. China
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8
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Tsai BP, Jimenez J, Lim S, Fitzgerald KD, Zhang M, Chuah CTH, Axelrod H, Wilson L, Ong ST, Semler BL, Waterman ML. A novel Bcr-Abl-mTOR-eIF4A axis regulates IRES-mediated translation of LEF-1. Open Biol 2015; 4:140180. [PMID: 25392452 PMCID: PMC4248067 DOI: 10.1098/rsob.140180] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Internal ribosome entry sites (IRESs) in cellular mRNAs direct expression of growth-promoting factors through an alternative translation mechanism that has yet to be fully defined. Lymphoid enhancer factor-1 (LEF-1), a Wnt-mediating transcription factor important for cell survival and metastasis in cancer, is produced via IRES-directed translation, and its mRNA is frequently upregulated in malignancies, including chronic myeloid leukaemia (CML). In this study, we determined that LEF1 expression is regulated by Bcr-Abl, the oncogenic protein that drives haematopoietic cell transformation to CML. We have previously shown that the LEF1 5′ untranslated region recruits a complex of proteins to its IRES, including the translation initiation factor eIF4A. In this report, we use two small molecule inhibitors, PP242 (dual mTOR (mammalian target of rapamycin) kinase inhibitor) and hippuristanol (eIF4A inhibitor), to define IRES regulation via a Bcr-Abl–mTOR–eIF4A axis in CML cell lines and primary patient leukaemias. We found that LEF1 and other IRESs are uniquely sensitive to the activities of Bcr-Abl/mTOR. Most notably, we discovered that eIF4A, an RNA helicase, elicits potent non-canonical effects on the LEF1 IRES. Hippuristanol inhibition of eIF4A stalls translation of IRES mRNA and triggers dissociation from polyribosomes. We propose that a combination drug strategy which targets mTOR and IRES-driven translation disrupts key factors that contribute to growth and proliferation in CML.
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Affiliation(s)
- Becky Pinjou Tsai
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA, USA
| | - Judith Jimenez
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA, USA
| | - Sharon Lim
- Cancer and Stem Cell Biology Signature Research Program, Duke-NUS Graduate Medical School, Singapore Department of Haematology, Singapore General Hospital, Singapore
| | - Kerry D Fitzgerald
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA, USA
| | - Min Zhang
- Division of Hematology/Oncology, Department of Medicine, School of Medicine, University of California, Irvine, CA, USA
| | - Charles T H Chuah
- Cancer and Stem Cell Biology Signature Research Program, Duke-NUS Graduate Medical School, Singapore Department of Haematology, Singapore General Hospital, Singapore
| | - Haley Axelrod
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA, USA
| | - Luke Wilson
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA, USA
| | - S Tiong Ong
- Cancer and Stem Cell Biology Signature Research Program, Duke-NUS Graduate Medical School, Singapore Department of Haematology, Singapore General Hospital, Singapore Department of Medical Oncology, National Cancer Centre, Singapore Department of Medicine, Duke University Medical Center, Durham, NC, USA
| | - Bert L Semler
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA, USA
| | - Marian L Waterman
- Department of Microbiology and Molecular Genetics, School of Medicine, University of California, Irvine, CA, USA
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Webb TE, Hughes A, Smalley DS, Spriggs KA. An internal ribosome entry site in the 5' untranslated region of epidermal growth factor receptor allows hypoxic expression. Oncogenesis 2015; 4:e134. [PMID: 25622307 PMCID: PMC4275558 DOI: 10.1038/oncsis.2014.43] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 09/29/2014] [Accepted: 10/15/2014] [Indexed: 12/25/2022] Open
Abstract
The expression of epidermal growth factor receptor (EGFR/ERBB1/HER1) is implicated in the progress of numerous cancers, a feature that has been exploited in the development of EGFR antibodies and EGFR tyrosine kinase inhibitors as anti-cancer drugs. However, EGFR also has important normal cellular functions, leading to serious side effects when EGFR is inhibited. One damaging characteristic of many oncogenes is the ability to be expressed in the hypoxic conditions associated with the tumour interior. It has previously been demonstrated that expression of EGFR is maintained in hypoxic conditions via an unknown mechanism of translational control, despite global translation rates generally being attenuated under hypoxic conditions. In this report, we demonstrate that the human EGFR 5′ untranslated region (UTR) sequence can initiate the expression of a downstream open reading frame via an internal ribosome entry site (IRES). We show that this effect is not due to either cryptic promoter activity or splicing events. We have investigated the requirement of the EGFR IRES for eukaryotic initiation factor 4A (eIF4A), which is an RNA helicase responsible for processing RNA secondary structure as part of translation initiation. Treatment with hippuristanol (a potent inhibitor of eIF4A) caused a decrease in EGFR 5′ UTR-driven reporter activity and also a reduction in EGFR protein level. Importantly, we show that expression of a reporter gene under the control of the EGFR IRES is maintained under hypoxic conditions despite a fall in global translation rates.
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Affiliation(s)
- T E Webb
- School of Pharmacy, University of Nottingham, Nottingham, UK
| | - A Hughes
- School of Pharmacy, University of Nottingham, Nottingham, UK
| | - D S Smalley
- School of Pharmacy, University of Nottingham, Nottingham, UK
| | - K A Spriggs
- School of Pharmacy, University of Nottingham, Nottingham, UK
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10
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Abstract
Recent work has demonstrated the importance of post-transcriptional gene regulation in toxic responses. In the present study, we used two rat models to investigate mRNA translation in the liver following xenobiotic-induced toxicity. By combining polysome profiling with genomic methodologies, we were able to assess global changes in hepatic mRNA translation. Dio3 (iodothyronine deiodinase type III) was identified as a gene that exhibited specific translational repression and had a functional role in a number of relevant canonical pathways. Western blot analysis indicated that this repression led to reduced D3 (the protein expressed by Dio3) levels, enhanced over time and with increased dose. Using Northern blotting techniques and qRT-PCR (quantitative reverse transcription–PCR), we confirmed further that there was no reduction in Dio3 mRNA, suggesting that translational repression of Dio3 is an important determinant of the reduced D3 protein expression following liver damage. Finally, we show that drug-induced hepatotoxicity appears to cause localized disruptions in thyroid hormone levels in the liver and plasma. We suggest that this leads to reduced translation of Dio3 mRNA, which results in decreased D3 production. It may therefore be possible that this is an important mechanism by which the liver can, upon early signs of damage, act rapidly to maintain its own energy equilibrium, thereby avoiding global disruption of the hypothalamic–pituitary–thyroid axis.
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11
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Chen J, Huang SY, Li ZY, Yuan ZG, Zhou DH, Petersen E, Zhang NZ, Zhu XQ. Protective immunity induced by a DNA vaccine expressing eIF4A of Toxoplasma gondii against acute toxoplasmosis in mice. Vaccine 2013; 31:1734-9. [PMID: 23370151 DOI: 10.1016/j.vaccine.2013.01.027] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 01/02/2013] [Accepted: 01/15/2013] [Indexed: 11/19/2022]
Abstract
Toxoplasma gondii is an obligate intracellular protozoan parasite infecting humans, mammals and birds. Eukaryotic translation initiation factor (eIF4A) is a newly identified protein associated with tachyzoite virulence. To evaluate the protective efficacy of T. gondii eIF4A, a DNA vaccine (pVAX-eIF4A) encoding T. gondii eIF4A (Tg-eIF4A) gene was constructed. The expression ability of this recombinant DNA plasmid was examined in Marc145 cells by IFA. Then, Kunming mice were intramuscularly immunized with pVAX-eIF4A and followed by challenge infection with the highly virulent T. gondii RH strain. The results showed that vaccination with pVAX-eIF4A elicited specific humoral responses, with high IgG antibody titers and specific lymphocyte proliferative responses. The cellular immune response was associated with significant production of IFN-γ, IL-2 in Kunming mice, and a mixed IgG1/IgG2a response with predominance of IgG2a production, indicating that a Th1 type response was elicited after immunization with pVAX-eIF4A. In addition, the increase of the percentage of CD8+ T cells in lymphoid in mice suggested the activation of MHC class I restricted antigen presentation pathways. After lethal challenge, the mice vaccinated with the pVAX-eIF4A showed a significantly prolonged survival time (23.0±5.5 days) compared with control mice which died within 7 days of challenge (P<0.05). These results demonstrate that pVAX-eIF4A could elicit strong humoral, Th1-type cellular immune responses and increase survival time of immunized mice, suggesting that eIF4A is a promising vaccine candidate against acute T. gondii infection in mice.
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Affiliation(s)
- Jia Chen
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, PR China
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12
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Maccecchini ML, Chang MY, Pan C, John V, Zetterberg H, Greig NH. Posiphen as a candidate drug to lower CSF amyloid precursor protein, amyloid-β peptide and τ levels: target engagement, tolerability and pharmacokinetics in humans. J Neurol Neurosurg Psychiatry 2012; 83:894-902. [PMID: 22791904 PMCID: PMC3415310 DOI: 10.1136/jnnp-2012-302589] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
AIM A first in human study to evaluate tolerability and pharmacokinetics followed by an early proof of mechanism (POM) study to determine whether the small orally, available molecule, Posiphen tartrate (Posiphen), lowers secreted (s) amyloid-β precursor protein (APP) α and -β, amyloid-β peptide (Aβ), tau (τ) and inflammatory markers in CSF of patients with mild cognitive impairment (MCI). STUDY DESIGN Posiphen single and multiple ascending dose phase 1 randomised, double blind, placebo-controlled safety, tolerance, pharmacokinetic studies were undertaken in a total of 120 healthy volunteers to define a dose that was then used in a small non-randomised study of five MCI subjects, used as their own controls, to define target engagement. MAIN OUTCOME MEASURES Pharmacodynamic: sAPPα, sAPPβ, Aβ(42), τ (total (t) and phosphorylated (p)) and inflammatory marker levels were time-dependently measured over 12 h and compared prior to and following 10 days of oral Posiphen treatment in four MCI subjects who completed the study. Pharmacokinetic: plasma and CSF drug and primary metabolite concentrations with estimated brain levels extrapolated from steady-state drug administration in rats. RESULTS Posiphen proved well tolerated and significantly lowered CSF levels of sAPPα, sAPPβ, t-τ, p-τ and specific inflammatory markers, and demonstrated a trend to lower CSF Aβ(42). CONCLUSIONS These results confirm preclinical POM studies, demonstrate that pharmacologically relevant drug/metabolite levels reach brain and support the continued clinical optimisation and evaluation of Posiphen for MCI and Alzheimer's disease.
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13
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Di Marco S, Cammas A, Lian XJ, Kovacs EN, Ma JF, Hall DT, Mazroui R, Richardson J, Pelletier J, Gallouzi IE. The translation inhibitor pateamine A prevents cachexia-induced muscle wasting in mice. Nat Commun 2012; 3:896. [PMID: 22692539 PMCID: PMC3621420 DOI: 10.1038/ncomms1899] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Accepted: 05/09/2012] [Indexed: 12/16/2022] Open
Abstract
Cachexia, or muscle-wasting syndrome, is one of the major causes of death in patients affected by diseases such as cancer, AIDS and sepsis. However, no effective anti-cachectic treatment is currently available. Here we show that a low dose of pateamine A, an inhibitor of translation initiation, prevents muscle wasting caused by the cytokines interferon γ and tumour necrosis factor α or by C26-adenocarcinoma tumours. Surprisingly, although high doses of pateamine A abrogate general translation, low doses selectively inhibit the expression of pro-cachectic factors such as inducible nitric oxide synthase. This selectivity depends on the 5'UTR of inducible nitric oxide synthase messenger RNA (mRNA) that, unlike the 5'UTR of MyoD mRNA, promotes the recruitment of inducible nitric oxide synthase mRNA to stress granules, where its translation is repressed. Collectively, our data provide a proof of principle that nontoxic doses of compounds such as pateamine A could be used as novel drugs to combat cachexia-induced muscle wasting.
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Affiliation(s)
- Sergio Di Marco
- Department of Biochemistry, Rosalind and Morris Goodman Cancer Center, McGill University, 3655 Promenade Sir William Osler, Montreal, Quebec, Canada
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14
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Ziegler ME, Souda P, Jin YP, Whitelegge JP, Reed EF. Characterization of the endothelial cell cytoskeleton following HLA class I ligation. PLoS One 2012; 7:e29472. [PMID: 22247778 PMCID: PMC3256144 DOI: 10.1371/journal.pone.0029472] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 11/29/2011] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Vascular endothelial cells (ECs) are a target of antibody-mediated allograft rejection. In vitro, when the HLA class I molecules on the surface of ECs are ligated by anti-HLA class I antibodies, cell proliferation and survival pathways are activated and this is thought to contribute to the development of antibody-mediated rejection. Crosslinking of HLA class I molecules by anti-HLA antibodies also triggers reorganization of the cytoskeleton, which induces the formation of F-actin stress fibers. HLA class I induced stress fiber formation is not well understood. METHODOLOGY AND PRINCIPAL FINDINGS The present study examines the protein composition of the cytoskeleton fraction of ECs treated with HLA class I antibodies and compares it to other agonists known to induce alterations of the cytoskeleton in endothelial cells. Analysis by tandem mass spectrometry revealed unique cytoskeleton proteomes for each treatment group. Using annotation tools a candidate list was created that revealed 12 proteins, which were unique to the HLA class I stimulated group. Eleven of the candidate proteins were phosphoproteins and exploration of their predicted kinases provided clues as to how these proteins may contribute to the understanding of HLA class I induced antibody-mediated rejection. Three of the candidates, eukaryotic initiation factor 4A1 (eIF4A1), Tropomyosin alpha 4-chain (TPM4) and DDX3X, were further characterized by Western blot and found to be associated with the cytoskeleton. Confocal microscopy analysis showed that class I ligation stimulated increased eIF4A1 co-localization with F-actin and paxillin. CONCLUSIONS/SIGNIFICANCE Colocalization of eIF4A1 with F-actin and paxillin following HLA class I ligation suggests that this candidate protein could be a target for understanding the mechanism(s) of class I mediated antibody-mediated rejection. This proteomic approach for analyzing the cytoskeleton of ECs can be applied to other agonists and various cells types as a method for uncovering novel regulators of cytoskeleton changes.
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Affiliation(s)
- Mary E. Ziegler
- The Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Puneet Souda
- The Pasarow Mass Spectrometry Laboratory, The Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Yi-Ping Jin
- The Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Julian P. Whitelegge
- The Pasarow Mass Spectrometry Laboratory, The Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
| | - Elaine F. Reed
- The Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America
- * E-mail:
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15
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Thole V, Peraldi A, Worland B, Nicholson P, Doonan JH, Vain P. T-DNA mutagenesis in Brachypodium distachyon. JOURNAL OF EXPERIMENTAL BOTANY 2012; 63:567-76. [PMID: 22090444 DOI: 10.1093/jxb/err333] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
During the past decade, Brachypodium distachyon has emerged as an attractive experimental system and genomics model for grass research. Numerous molecular tools and genomics resources have already been developed. Functional genomics resources, including mutant collections, expression/tiling microarray, mapping populations, and genome re-sequencing for natural accessions, are rapidly being developed and made available to the community. In this article, the focus is on the current status of systematic T-DNA mutagenesis in Brachypodium. Large collections of T-DNA-tagged lines are being generated by a community of laboratories in the context of the International Brachypodium Tagging Consortium. To date, >13 000 lines produced by the BrachyTAG programme and USDA-ARS Western Regional Research Center are available by online request. The utility of these mutant collections is illustrated with some examples from the BrachyTAG collection at the John Innes Centre-such as those in the eukaryotic initiation factor 4A (eIF4A) and brassinosteroid insensitive-1 (BRI1) genes. A series of other mutants exhibiting growth phenotypes is also presented. These examples highlight the value of Brachypodium as a model for grass functional genomics.
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Affiliation(s)
- Vera Thole
- John Innes Centre, Department of Crop Genetics, Norwich Research Park, Norwich NR4 7UH, UK
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Vain P, Thole V, Worland B, Opanowicz M, Bush MS, Doonan JH. A T-DNA mutation in the RNA helicase eIF4A confers a dose-dependent dwarfing phenotype in Brachypodium distachyon. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2011; 66:929-940. [PMID: 21457366 DOI: 10.1111/j.1365-313x.2011.04555.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In a survey of the BrachyTAG mutant population of Brachypodium distachyon, we identified a line carrying a T-DNA insertion in one of the two eukaryotic initiation factor 4A (eIF4A) genes present in the nuclear genome. The eif4a homozygous mutant plants were slow-growing, and exhibited reduced final plant stature due to a decrease in both cell number and cell size, consistent with roles for eIF4A in both cell division and cell growth. Hemizygous plants displayed a semi-dwarfing phenotype, in which stem length was reduced but leaf length was normal. Linkage between the insertion site and phenotype was confirmed, and we show that the level of eIF4A protein is strongly reduced in the mutant. Transformation of the Brachypodium homozygous mutant with a genomic copy of the Arabidopsis eIF4A-1 gene partially complemented the growth phenotype, indicating that gene function is conserved between mono- and dicotyledonous species. This study identifies eIF4A as a novel dose-dependent regulator of stem elongation, and demonstrates the utility of Brachypodium as a model for grass and cereals research.
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Affiliation(s)
- Philippe Vain
- Crop Genetics Department, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
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