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Marshall GF, Fasol M, Davies FCJ, Le Seelleur M, Fernandez Alvarez A, Bennett-Ness C, Gonzalez-Sulser A, Abbott CM. Face-valid phenotypes in a mouse model of the most common mutation in EEF1A2-related neurodevelopmental disorder. Dis Model Mech 2024; 17:dmm050501. [PMID: 38179821 PMCID: PMC10855229 DOI: 10.1242/dmm.050501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 12/21/2023] [Indexed: 01/06/2024] Open
Abstract
De novo heterozygous missense mutations in EEF1A2, encoding neuromuscular translation-elongation factor eEF1A2, are associated with developmental and epileptic encephalopathies. We used CRISPR/Cas9 to recapitulate the most common mutation, E122K, in mice. Although E122K heterozygotes were not observed to have convulsive seizures, they exhibited frequent electrographic seizures and EEG abnormalities, transient early motor deficits and growth defects. Both E122K homozygotes and Eef1a2-null mice developed progressive motor abnormalities, with E122K homozygotes reaching humane endpoints by P31. The null phenotype is driven by progressive spinal neurodegeneration; however, no signs of neurodegeneration were observed in E122K homozygotes. The E122K protein was relatively stable in neurons yet highly unstable in skeletal myocytes, suggesting that the E122K/E122K phenotype is instead driven by loss of function in muscle. Nevertheless, motor abnormalities emerged far earlier in E122K homozygotes than in nulls, suggesting a toxic gain of function and/or a possible dominant-negative effect. This mouse model represents the first animal model of an EEF1A2 missense mutation with face-valid phenotypes and has provided mechanistic insights needed to inform rational treatment design.
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Affiliation(s)
- Grant F. Marshall
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Melissa Fasol
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, UK
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Faith C. J. Davies
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Matthew Le Seelleur
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
| | - Alejandra Fernandez Alvarez
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
| | - Cavan Bennett-Ness
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
| | - Alfredo Gonzalez-Sulser
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, UK
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Catherine M. Abbott
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, UK
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2
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Paulet A, Bennett-Ness C, Ageorges F, Trost D, Green A, Goudie D, Jewell R, Kraatari-Tiri M, Piard J, Coubes C, Lam W, Lynch SA, Groeschel S, Ramond F, Fluss J, Fagerberg C, Brasch Andersen C, Varvagiannis K, Kleefstra T, Gérard B, Fradin M, Vitobello A, Tenconi R, Denommé-Pichon AS, Vincent-Devulder A, Haack T, Marsh JA, Laulund LW, Grimmel M, Riess A, de Boer E, Padilla-Lopez S, Bakhtiari S, Ostendorf A, Zweier C, Smol T, Willems M, Faivre L, Scala M, Striano P, Bagnasco I, Koboldt D, Iascone M, Suerink M, Kruer MC, Levy J, Verloes A, Abbott CM, Ruaud L. Correction: Expansion of the neurodevelopmental phenotype of individuals with EEF1A2 variants and genotype-phenotype study. Eur J Hum Genet 2024:10.1038/s41431-024-01606-x. [PMID: 38565641 DOI: 10.1038/s41431-024-01606-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024] Open
Affiliation(s)
- Alix Paulet
- Département de Génétique, Hôpital Robert-Debré, Paris, France.
| | - Cavan Bennett-Ness
- Centre for Genomic and Experimental Medicine and Simons Initiative for the Developing Brain, Institute of Genetics and Cancer, Edinburgh, Scotland, UK
| | | | | | - Andrew Green
- UCD School of Medicine and Medical Science Consultant in Clinical Genetics, Dublin, Ireland
| | - David Goudie
- Regional Genetics Service, NHS Tayside, Dundee, Scotland, UK
| | - Rosalyn Jewell
- Yorkshire Regional Genetics Service, Leeds Teaching Hospitals NHS Trust, Leeds, England, UK
| | - Minna Kraatari-Tiri
- Department of Clinical Genetics, Research unit of Clinical Medicine, Medical Research Center Oulu, Oulu, Finland
- Oulu University Hospital and University of Oulu, Oulu, Finland
| | - Juliette Piard
- Centre de Génétique Humaine, CHU Besançon, Besançon, France
| | - Christine Coubes
- Service de Génétique Médicale, CHU de Montpellier, Montpellier, France
| | - Wayne Lam
- South-East of Scotland Clinical Genetics Service, General Hospital, Edinburgh, Scotland, UK
| | - Sally Ann Lynch
- Clinical Genetics, Children's Health Ireland, Dublin, Ireland
| | - Samuel Groeschel
- Department of Neuropediatrics, University Children's Hospital, Tuebingen, Germany
| | - Francis Ramond
- Service de Génétique, CHU Saint-Etienne - Hôpital Nord, Saint-Etienne, France
| | - Joël Fluss
- University Hospitals of Geneva, Geneva, Switzerland
| | - Christina Fagerberg
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
| | | | | | - Tjitske Kleefstra
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, The Netherlands
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
- Center of Excellence for Neuropsychiatry, Vincent van Gogh Institute for Psychiatry, Venray, The Netherlands
| | | | - Mélanie Fradin
- Service de Génétique Médicale, Hôpital Sud, CHU de Rennes, Rennes, France
| | - Antonio Vitobello
- UMR-Inserm, Génétique des Anomalies du développement, Université de Bourgogne Franche-Comté, Dijon, France
| | - Romano Tenconi
- Servizio di Genetica Medica, Dipartimento di Pediatra, Padova, Italia
| | - Anne-Sophie Denommé-Pichon
- Unité Fonctionnelle Innovation en Diagnostic génomique des maladies rares, FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France
- UMR1231 GAD, Inserm - Université Bourgogne-Franche Comté, Dijon, France
| | | | - Tobias Haack
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Joseph A Marsh
- MRC Human Genetics Unit, Western General Hospital, University of Edinburgh, Edinburgh, Scotland, UK
| | | | - Mona Grimmel
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Angelika Riess
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Elke de Boer
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, The Netherlands
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - Sergio Padilla-Lopez
- Pediatric Movement Disorders Program, Division of Pediatric Neurology, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Somayeh Bakhtiari
- Pediatric Movement Disorders Program, Division of Pediatric Neurology, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Adam Ostendorf
- Steve and Cindy Rasmussen Institute for Genomic Medicine Nationwide Children's Hospital, Colombus, OH, USA
- Department of Pediatrics, The Ohio State University College of Medicine, Colombus, OH, USA
| | - Christiane Zweier
- Department of Human Genetics, Inselspital Bern, University of Bern, 3010, Bern, Switzerland
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - Thomas Smol
- University of Lille, EA7364-RADEME, Medical Genetics Institute, Chu Lille, Lille, France
| | - Marjolaine Willems
- Medical Genetic Department for Rare Diseases and Personalized Medicine, Reference Center AD SOOR, AnDDI-RARE, Groupe DI, Inserm U1298, INM, Montpellier University, Montpellier, France
- Centre Hospitalier Universitaire de Montpellier, Montpellier, France
| | - Laurence Faivre
- UMR1231 GAD, Inserm, Université de Bourgogne-Franche Comté, Dijon, France
- Centre de Référence Maladies Rares « Anomalies du développement et syndromes malformatifs », Centre de Génétique, FHU-TRANSLAD et Institut GIMI, CHU dijon, Bourgogne, Dijon, France
| | - Marcello Scala
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Irene Bagnasco
- Division of Child Neuropsychiatry, Martini Hospital, Torino, Italy
| | - Daniel Koboldt
- Steve and Cindy Rasmussen Institute for Genomic Medicine Nationwide Children's Hospital, Colombus, OH, USA
| | | | - Manon Suerink
- Department of Clinical Genetics, Leiden University Medical Centre, Leiden, The Netherlands
| | - Michael C Kruer
- Pediatric Movement Disorders Program, Division of Pediatric Neurology, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Jonathan Levy
- Département de Génétique, Hôpital Robert-Debré, Paris, France
| | - Alain Verloes
- Département de Génétique, Hôpital Robert-Debré, Paris, France
| | - Catherine M Abbott
- Centre for Genomic and Experimental Medicine and Simons Initiative for the Developing Brain, Institute of Genetics and Cancer, Edinburgh, Scotland, UK
| | - Lyse Ruaud
- Département de Génétique, Hôpital Robert-Debré, Paris, France
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3
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Treekitkarnmongkol W, Solis LM, Sankaran D, Gagea M, Singh PK, Mistry R, Nguyen T, Kai K, Liu J, Sasai K, Jitsumori Y, Liu J, Nagao N, Stossi F, Mancini MA, Wistuba II, Thompson AM, Lee JM, Cadiñanos J, Wong KK, Abbott CM, Sahin AA, Liu S, Katayama H, Sen S. eEF1A2 promotes PTEN-GSK3β-SCF complex-dependent degradation of Aurora kinase A and is inactivated in breast cancer. Sci Signal 2024; 17:eadh4475. [PMID: 38442201 DOI: 10.1126/scisignal.adh4475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 02/15/2024] [Indexed: 03/07/2024]
Abstract
The translation elongation factor eEF1A promotes protein synthesis. Its methylation by METTL13 increases its activity, supporting tumor growth. However, in some cancers, a high abundance of eEF1A isoforms is associated with a good prognosis. Here, we found that eEF1A2 exhibited oncogenic or tumor-suppressor functions depending on its interaction with METTL13 or the phosphatase PTEN, respectively. METTL13 and PTEN competed for interaction with eEF1A2 in the same structural domain. PTEN-bound eEF1A2 promoted the ubiquitination and degradation of the mitosis-promoting Aurora kinase A in the S and G2 phases of the cell cycle. eEF1A2 bridged the interactions between the SKP1-CUL1-FBXW7 (SCF) ubiquitin ligase complex, the kinase GSK3β, and Aurora-A, thereby facilitating the phosphorylation of Aurora-A in a degron site that was recognized by FBXW7. Genetic ablation of Eef1a2 or Pten in mice resulted in a greater abundance of Aurora-A and increased cell cycling in mammary tumors, which was corroborated in breast cancer tissues from patients. Reactivating this pathway using fimepinostat, which relieves inhibitory signaling directed at PTEN and increases FBXW7 expression, combined with inhibiting Aurora-A with alisertib, suppressed breast cancer cell proliferation in culture and tumor growth in vivo. The findings demonstrate a therapeutically exploitable, tumor-suppressive role for eEF1A2 in breast cancer.
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Affiliation(s)
- Warapen Treekitkarnmongkol
- Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Luisa M Solis
- Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Deivendran Sankaran
- Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Mihai Gagea
- Department of Veterinary Medicine and Surgery, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Pankaj K Singh
- Center for Translational Cancer Research, Texas A&M Health Science Center, Institute of Biosciences and Technology, Houston, TX 77030, USA
| | - Ragini Mistry
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Tristian Nguyen
- Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Kazuharu Kai
- Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Jiajun Liu
- State Key Laboratory of Bioreactor Engineering, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China
| | - Kaori Sasai
- Department of Molecular Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan
| | - Yoshimi Jitsumori
- Department of Molecular Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan
| | - Jianwen Liu
- State Key Laboratory of Bioreactor Engineering, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China
| | - Norio Nagao
- Department of Life and Environmental Sciences, Prefectural University of Hiroshima, Shobara, 727-0023, Japan
| | - Fabio Stossi
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Michael A Mancini
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ignacio I Wistuba
- Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | - Jonathan M Lee
- Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Juan Cadiñanos
- Fundación Centro Médico de Asturias, 33193 Oviedo, Spain
- Instituto de Medicina Oncológica y Molecular de Asturias (IMOMA), 33193 Oviedo, Spain
| | - Kwong-Kwok Wong
- Department of Gynecologic Oncology and Reproductive Medicine, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Catherine M Abbott
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Aysegul A Sahin
- Department of Pathology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Suyu Liu
- Department of Biostatistics, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Hiroshi Katayama
- Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Department of Molecular Oncology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan
| | - Subrata Sen
- Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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4
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Paulet A, Bennett-Ness C, Ageorges F, Trost D, Green A, Goudie D, Jewell R, Kraatari-Tiri M, Piard J, Coubes C, Lam W, Lynch SA, Groeschel S, Ramond F, Fluss J, Fagerberg C, Brasch Andersen C, Varvagiannis K, Kleefstra T, Gérard B, Fradin M, Vitobello A, Tenconi R, Denommé-Pichon AS, Vincent-Devulder A, Haack T, Marsh JA, Laulund LW, Grimmel M, Riess A, de Boer E, Padilla-Lopez S, Bakhtiari S, Ostendorf A, Zweier C, Smol T, Willems M, Faivre L, Scala M, Striano P, Bagnasco I, Koboldt D, Iascone M, Suerink M, Kruer MC, Levy J, Verloes A, Abbott CM, Ruaud L. Expansion of the neurodevelopmental phenotype of individuals with EEF1A2 variants and genotype-phenotype study. Eur J Hum Genet 2024:10.1038/s41431-024-01560-8. [PMID: 38355961 DOI: 10.1038/s41431-024-01560-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 01/10/2024] [Accepted: 02/01/2024] [Indexed: 02/16/2024] Open
Abstract
Translation elongation factor eEF1A2 constitutes the alpha subunit of the elongation factor-1 complex, responsible for the enzymatic binding of aminoacyl-tRNA to the ribosome. Since 2012, 21 pathogenic missense variants affecting EEF1A2 have been described in 42 individuals with a severe neurodevelopmental phenotype including epileptic encephalopathy and moderate to profound intellectual disability (ID), with neurological regression in some patients. Through international collaborative call, we collected 26 patients with EEF1A2 variants and compared them to the literature. Our cohort shows a significantly milder phenotype. 83% of the patients are walking (vs. 29% in the literature), and 84% of the patients have language skills (vs. 15%). Three of our patients do not have ID. Epilepsy is present in 63% (vs. 93%). Neurological examination shows a less severe phenotype with significantly less hypotonia (58% vs. 96%), and pyramidal signs (24% vs. 68%). Cognitive regression was noted in 4% (vs. 56% in the literature). Among individuals over 10 years, 56% disclosed neurocognitive regression, with a mean age of onset at 2 years. We describe 8 novel missense variants of EEF1A2. Modeling of the different amino-acid sites shows that the variants associated with a severe phenotype, and the majority of those associated with a moderate phenotype, cluster within the switch II region of the protein and thus may affect GTP exchange. In contrast, variants associated with milder phenotypes may impact secondary functions such as actin binding. We report the largest cohort of individuals with EEF1A2 variants thus far, allowing us to expand the phenotype spectrum and reveal genotype-phenotype correlations.
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Affiliation(s)
- Alix Paulet
- Département de Génétique, Hôpital Robert-Debré, Paris, France.
| | - Cavan Bennett-Ness
- Centre for Genomic and Experimental Medicine and Simons Initiative for the Developing Brain, Institute of Genetics and Cancer, Edinburgh, Scotland, UK
| | | | | | - Andrew Green
- UCD School of Medicine and Medical Science Consultant in Clinical Genetics, Dublin, Ireland
| | - David Goudie
- Regional Genetics Service, NHS Tayside, Dundee, Scotland, UK
| | - Rosalyn Jewell
- Yorkshire Regional Genetics Service, Leeds Teaching Hospitals NHS Trust, Leeds, England, UK
| | - Minna Kraatari-Tiri
- Department of Clinical Genetics, Research unit of Clinical Medicine, Medical Research Center Oulu, Oulu, Finland
- Oulu University Hospital and University of Oulu, Oulu, Finland
| | - Juliette Piard
- Centre de Génétique Humaine, CHU Besançon, Besançon, France
| | - Christine Coubes
- Service de Génétique Médicale, CHU de Montpellier, Montpellier, France
| | - Wayne Lam
- South-East of Scotland Clinical Genetics Service, General Hospital, Edinburgh, Scotland, UK
| | - Sally Ann Lynch
- Clinical Genetics, Children's Health Ireland, Dublin, Ireland
| | - Samuel Groeschel
- Department of Neuropediatrics, University Children's Hospital, Tuebingen, Germany
| | - Francis Ramond
- Service de Génétique, CHU Saint-Etienne - Hôpital Nord, Saint-Etienne, France
| | - Joël Fluss
- University Hospitals of Geneva, Geneva, Switzerland
| | - Christina Fagerberg
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
| | | | | | - Tjitske Kleefstra
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, The Netherlands
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
- Center of Excellence for Neuropsychiatry, Vincent van Gogh Institute for Psychiatry, Venray, The Netherlands
| | | | - Mélanie Fradin
- Service de Génétique Médicale, Hôpital Sud, CHU de Rennes, Rennes, France
| | - Antonio Vitobello
- UMR-Inserm, Génétique des Anomalies du développement, Université de Bourgogne Franche-Comté, Dijon, France
| | - Romano Tenconi
- Servizio di Genetica Medica, Dipartimento di Pediatra, Padova, Italia
| | - Anne-Sophie Denommé-Pichon
- Unité Fonctionnelle Innovation en Diagnostic génomique des maladies rares, FHU-TRANSLAD, CHU Dijon Bourgogne, Dijon, France
- UMR1231 GAD, Inserm - Université Bourgogne-Franche Comté, Dijon, France
| | | | - Tobias Haack
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Joseph A Marsh
- MRC Human Genetics Unit, Western General Hospital, University of Edinburgh, Edinburgh, Scotland, UK
| | | | - Mona Grimmel
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Angelika Riess
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Elke de Boer
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, The Netherlands
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - Sergio Padilla-Lopez
- Pediatric Movement Disorders Program, Division of Pediatric Neurology, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Somayeh Bakhtiari
- Pediatric Movement Disorders Program, Division of Pediatric Neurology, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Adam Ostendorf
- Steve and Cindy Rasmussen Institute for Genomic Medicine Nationwide Children's Hospital, Colombus, Ohio, USA
- Department of Pediatrics, The Ohio State University College of Medicine, Colombus, USA
| | - Christiane Zweier
- Department of Human Genetics, Inselspital Bern, University of Bern, 3010, Bern, Switzerland
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - Thomas Smol
- University of Lille, EA7364-RADEME, Medical Genetics Institute, Chu Lille, Lille, France
| | - Marjolaine Willems
- Medical Genetic Department for Rare Diseases and Personalized Medicine, Reference Center AD SOOR, AnDDI-RARE, Groupe DI, Inserm U1298, INM, Montpellier University, Montpellier, France
- Centre Hospitalier Universitaire de Montpellier, Montpellier, France
| | - Laurence Faivre
- UMR1231 GAD, Inserm, Université de Bourgogne-Franche Comté, Dijon, France
- Centre de Référence Maladies Rares « Anomalies du développement et syndromes malformatifs », Centre de Génétique, FHU-TRANSLAD et Institut GIMI, CHU dijon, Bourgogne, Dijon, France
| | - Marcello Scala
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Irene Bagnasco
- Division of Child Neuropsychiatry, Martini Hospital, Torino, Italy
| | - Daniel Koboldt
- Steve and Cindy Rasmussen Institute for Genomic Medicine Nationwide Children's Hospital, Colombus, Ohio, USA
| | | | - Manon Suerink
- Department of Clinical Genetics, Leiden University Medical Centre, Leiden, the Netherlands
| | - Michael C Kruer
- Pediatric Movement Disorders Program, Division of Pediatric Neurology, Barrow Neurological Institute, Phoenix Children's Hospital, Phoenix, AZ, USA
| | - Jonathan Levy
- Département de Génétique, Hôpital Robert-Debré, Paris, France
| | - Alain Verloes
- Département de Génétique, Hôpital Robert-Debré, Paris, France
| | - Catherine M Abbott
- Centre for Genomic and Experimental Medicine and Simons Initiative for the Developing Brain, Institute of Genetics and Cancer, Edinburgh, Scotland, UK
| | - Lyse Ruaud
- Département de Génétique, Hôpital Robert-Debré, Paris, France
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5
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Davies FCJ, Marshall GF, Pegram E, Gadd D, Abbott CM. Endogenous epitope tagging of eEF1A2 in mice reveals early embryonic expression of eEF1A2 and subcellular compartmentalisation of neuronal eEF1A1 and eEF1A2. Mol Cell Neurosci 2023; 126:103879. [PMID: 37429391 DOI: 10.1016/j.mcn.2023.103879] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 06/29/2023] [Accepted: 07/06/2023] [Indexed: 07/12/2023] Open
Abstract
All vertebrate species express two independently-encoded forms of translation elongation factor eEF1A. In humans and mice eEF1A1 and eEF1A2 are 92 % identical at the amino acid level, but the well conserved developmental switch between the two variants in specific tissues suggests the existence of important functional differences. Heterozygous mutations in eEF1A2 result in neurodevelopmental disorders in humans; the mechanism of pathogenicity is unclear, but one hypothesis is that there is a dominant negative effect on eEF1A1 during development. The high degree of similarity between the eEF1A proteins has complicated expression analysis in the past; here we describe a gene edited mouse line in which we have introduced a V5 tag in the gene encoding eEF1A2. Expression analysis using anti-V5 and anti-eEF1A1 antibodies demonstrates that, in contrast to the prevailing view that eEF1A2 is only expressed postnatally, it is expressed from as early as E11.5 in the developing neural tube. Two colour immunofluorescence also reveals coordinated switching between eEF1A1 and eEF1A2 in different regions of postnatal brain. Completely reciprocal expression of the two variants is seen in post-weaning mouse brain with eEF1A1 expressed in oligodendrocytes and astrocytes and eEF1A2 in neuronal soma. Although eEF1A1 is absent from neuronal cell bodies after development, it is widely expressed in axons. This expression does not appear to coincide with myelin sheaths originating from oligodendrocytes but rather results from localised translation within the axon, suggesting that both variants are transcribed in neurons but show completely distinct subcellular localisation at the protein level. These findings will form an underlying framework for understanding how missense mutations in eEF1A2 result in neurodevelopmental disorders.
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Affiliation(s)
- Faith C J Davies
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, United Kingdom; Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
| | - Grant F Marshall
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, United Kingdom; Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
| | - Eleanor Pegram
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, United Kingdom
| | - Danni Gadd
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, United Kingdom
| | - Catherine M Abbott
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, United Kingdom; Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom.
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6
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Gospodinova KO, Olsen D, Kaas M, Anderson SM, Phillips J, Walker RM, Bermingham ML, Payne AL, Giannopoulos P, Pandya D, Spires-Jones TL, Abbott CM, Porteous DJ, Glerup S, Evans KL. Loss of SORCS2 is Associated with Neuronal DNA Double-Strand Breaks. Cell Mol Neurobiol 2023; 43:237-249. [PMID: 34741697 PMCID: PMC9813074 DOI: 10.1007/s10571-021-01163-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 10/29/2021] [Indexed: 01/09/2023]
Abstract
SORCS2 is one of five proteins that constitute the Vps10p-domain receptor family. Members of this family play important roles in cellular processes linked to neuronal survival, differentiation and function. Genetic and functional studies implicate SORCS2 in cognitive function, as well as in neurodegenerative and psychiatric disorders. DNA damage and DNA repair deficits are linked to ageing and neurodegeneration, and transient neuronal DNA double-strand breaks (DSBs) also occur as a result of neuronal activity. Here, we report a novel role for SORCS2 in DSB formation. We show that SorCS2 loss is associated with elevated DSB levels in the mouse dentate gyrus and that knocking out SORCS2 in a human neuronal cell line increased Topoisomerase IIβ-dependent DSB formation and reduced neuronal viability. Neuronal stimulation had no impact on levels of DNA breaks in vitro, suggesting that the observed differences may not be the result of aberrant neuronal activity in these cells. Our findings are consistent with studies linking the VPS10 receptors and DNA damage to neurodegenerative conditions.
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Affiliation(s)
- Katerina O. Gospodinova
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Ditte Olsen
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Mathias Kaas
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Susan M. Anderson
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Jonathan Phillips
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Rosie M. Walker
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK ,Present Address: University of Edinburgh, Chancellor’s Building, 49, Edinburgh, EH16 4SB UK
| | - Mairead L. Bermingham
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Abigail L. Payne
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Panagiotis Giannopoulos
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Divya Pandya
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Tara L. Spires-Jones
- Centre for Discovery Brain Sciences, UK Dementia Research Institute, University of Edinburgh, Edinburgh, EH8 9XD UK
| | - Catherine M. Abbott
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - David J. Porteous
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
| | - Simon Glerup
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
| | - Kathryn L. Evans
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU UK
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7
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Bengani H, Grozeva D, Moyon L, Bhatia S, Louros SR, Hope J, Jackson A, Prendergast JG, Owen LJ, Naville M, Rainger J, Grimes G, Halachev M, Murphy LC, Spasic-Boskovic O, van Heyningen V, Kind P, Abbott CM, Osterweil E, Raymond FL, Roest Crollius H, FitzPatrick DR. Identification and functional modelling of plausibly causative cis-regulatory variants in a highly-selected cohort with X-linked intellectual disability. PLoS One 2021; 16:e0256181. [PMID: 34388204 PMCID: PMC8362966 DOI: 10.1371/journal.pone.0256181] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 08/01/2021] [Indexed: 11/18/2022] Open
Abstract
Identifying causative variants in cis-regulatory elements (CRE) in neurodevelopmental disorders has proven challenging. We have used in vivo functional analyses to categorize rigorously filtered CRE variants in a clinical cohort that is plausibly enriched for causative CRE mutations: 48 unrelated males with a family history consistent with X-linked intellectual disability (XLID) in whom no detectable cause could be identified in the coding regions of the X chromosome (chrX). Targeted sequencing of all chrX CRE identified six rare variants in five affected individuals that altered conserved bases in CRE targeting known XLID genes and segregated appropriately in families. Two of these variants, FMR1CRE and TENM1CRE, showed consistent site- and stage-specific differences of enhancer function in the developing zebrafish brain using dual-color fluorescent reporter assay. Mouse models were created for both variants. In male mice Fmr1CRE induced alterations in neurodevelopmental Fmr1 expression, olfactory behavior and neurophysiological indicators of FMRP function. The absence of another likely causative variant on whole genome sequencing further supported FMR1CRE as the likely basis of the XLID in this family. Tenm1CRE mice showed no phenotypic anomalies. Following the release of gnomAD 2.1, reanalysis showed that TENM1CRE exceeded the maximum plausible population frequency of a XLID causative allele. Assigning causative status to any ultra-rare CRE variant remains problematic and requires disease-relevant in vivo functional data from multiple sources. The sequential and bespoke nature of such analyses renders them time-consuming and challenging to scale for routine clinical use.
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Affiliation(s)
- Hemant Bengani
- MRC Human Genetics Unit, IGMM, University of Edinburgh (UoE), Edinburgh, United Kingdom
| | - Detelina Grozeva
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
- Institute of Psychological Medicine & Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom
| | - Lambert Moyon
- Ecole Normale Supérieure, Institut de Biologie de l’ENS, IBENS, Paris, France
| | - Shipra Bhatia
- MRC Human Genetics Unit, IGMM, University of Edinburgh (UoE), Edinburgh, United Kingdom
| | - Susana R. Louros
- Centre for Discovery Brain Sciences, Patrick Wild Centre, University of Edinburgh, Edinburgh, United Kingdom
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, United Kingdom
| | - Jilly Hope
- Institute of Genomic and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Adam Jackson
- Centre for Discovery Brain Sciences, Patrick Wild Centre, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Liusaidh J. Owen
- MRC Human Genetics Unit, IGMM, University of Edinburgh (UoE), Edinburgh, United Kingdom
| | - Magali Naville
- Ecole Normale Supérieure, Institut de Biologie de l’ENS, IBENS, Paris, France
| | - Jacqueline Rainger
- MRC Human Genetics Unit, IGMM, University of Edinburgh (UoE), Edinburgh, United Kingdom
| | - Graeme Grimes
- Institute of Genomic and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Mihail Halachev
- Institute of Genomic and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Laura C. Murphy
- Institute of Genomic and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Olivera Spasic-Boskovic
- East Midlands and East of England NHS Genomic Laboratory Hub, Molecular Genetics, Adden brooke’s Hospital, Cambridge University Hospitals NHS Foundation Trust Cambridge, Cambridge, United Kingdom
| | | | - Peter Kind
- Centre for Discovery Brain Sciences, Patrick Wild Centre, University of Edinburgh, Edinburgh, United Kingdom
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, United Kingdom
| | - Catherine M. Abbott
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, United Kingdom
- Institute of Genomic and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Emily Osterweil
- Centre for Discovery Brain Sciences, Patrick Wild Centre, University of Edinburgh, Edinburgh, United Kingdom
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, United Kingdom
| | - F. Lucy Raymond
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, United Kingdom
| | | | - David R. FitzPatrick
- MRC Human Genetics Unit, IGMM, University of Edinburgh (UoE), Edinburgh, United Kingdom
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, United Kingdom
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8
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Davies FCJ, Hope JE, McLachlan F, Marshall GF, Kaminioti-Dumont L, Qarkaxhija V, Nunez F, Dando O, Smith C, Wood E, MacDonald J, Hardt O, Abbott CM. Recapitulation of the EEF1A2 D252H neurodevelopmental disorder-causing missense mutation in mice reveals a toxic gain of function. Hum Mol Genet 2021; 29:1592-1606. [PMID: 32160274 DOI: 10.1093/hmg/ddaa042] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 03/04/2020] [Accepted: 03/05/2020] [Indexed: 12/24/2022] Open
Abstract
Heterozygous de novo mutations in EEF1A2, encoding the tissue-specific translation elongation factor eEF1A2, have been shown to cause neurodevelopmental disorders including often severe epilepsy and intellectual disability. The mutational profile is unusual; ~50 different missense mutations have been identified but no obvious loss of function mutations, though large heterozygous deletions are known to be compatible with life. A key question is whether the heterozygous missense mutations operate through haploinsufficiency or a gain of function mechanism, an important prerequisite for design of therapeutic strategies. In order both to address this question and to provide a novel model for neurodevelopmental disorders resulting from mutations in EEF1A2, we created a new mouse model of the D252H mutation. This mutation causes the eEF1A2 protein to be expressed at lower levels in brain but higher in muscle in the mice. We compared both heterozygous and homozygous D252H and null mutant mice using behavioural and motor phenotyping alongside molecular modelling and analysis of binding partners. Although the proteomic analysis pointed to a loss of function for the D252H mutant protein, the D252H homozygous mice were more severely affected than null homozygotes on the same genetic background. Mice that are heterozygous for the missense mutation show no behavioural abnormalities but do have sex-specific deficits in body mass and motor function. The phenotyping of our novel mouse lines, together with analysis of molecular modelling and interacting proteins, suggest that the D252H mutation results in a gain of function.
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Affiliation(s)
- Faith C J Davies
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
| | - Jilly E Hope
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Fiona McLachlan
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Grant F Marshall
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Laura Kaminioti-Dumont
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Vesa Qarkaxhija
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Francis Nunez
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Owen Dando
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom.,Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
| | - Colin Smith
- Academic Department of Neuropathology, Centre for Clinical Brain Sciences, Edinburgh, EH16 4SB, United Kingdom
| | - Emma Wood
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom.,Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
| | - Josephine MacDonald
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom
| | - Oliver Hardt
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom.,Department of Psychology, McGill University, Montreal, QC H3A 1B1, Canada
| | - Catherine M Abbott
- Centre for Genomic & Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh EH4 2XU, United Kingdom.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, United Kingdom
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9
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Abstract
In most mouse models of disease, the outward manifestation of a disorder can be measured easily, can be assessed with a trivial test such as hind limb clasping, or can even be observed simply by comparing the gross morphological characteristics of mutant and wild-type littermates. But what if we are trying to model a disorder with a phenotype that appears only sporadically and briefly, like epileptic seizures? The purpose of this Review is to highlight the challenges of modelling epilepsy, in which the most obvious manifestation of the disorder, seizures, occurs only intermittently, possibly very rarely and often at times when the mice are not under direct observation. Over time, researchers have developed a number of ways in which to overcome these challenges, each with their own advantages and disadvantages. In this Review, we describe the genetics of epilepsy and the ways in which genetically altered mouse models have been used. We also discuss the use of induced models in which seizures are brought about by artificial stimulation to the brain of wild-type animals, and conclude with the ways these different approaches could be used to develop a wider range of anti-seizure medications that could benefit larger patient populations. Summary: This Review discusses the challenges of modelling epilepsy in mice, a condition in which the outward manifestation of the disorder appears only sporadically, and reviews possible solutions encompassing both genetic and induced models.
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Affiliation(s)
- Grant F Marshall
- Centre for Genomic and Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Alfredo Gonzalez-Sulser
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, UK.,Centre for Discovery Brain Sciences, 1 George Square, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Catherine M Abbott
- Centre for Genomic and Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK .,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, UK
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10
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11
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Abbott CM. Precision Medicine in Epilepsy-The Way Forward? ACS Chem Neurosci 2019; 10:2080-2081. [PMID: 30991807 DOI: 10.1021/acschemneuro.9b00162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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12
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Treekitkarnmongkol W, Solis LM, Kai K, Thompson AM, Tian W, Wistuba II, Sasai K, Jltsumori Y, Sahin AA, Hawke DH, Lee JM, Qin L, Bawa-Khalfe T, Rad R, Wong KK, Abbott CM, Katayama H, Sen S. Abstract P1-05-05: eEF1A2 facilitates PTEN-GSK3β mediated Aurora-A protein degradation during S-G2 phase inactivated in PTEN-deficient breast cancer. Cancer Res 2019. [DOI: 10.1158/1538-7445.sabcs18-p1-05-05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
The AURKA gene, encoding Aurora kinase-A (Aurora-A), is frequently amplified and overexpressed across multiple cancer types correlating with poor prognosis. Although the AURKA gene is frequently amplified in human cancers, underlying mechanism(s) for Aurora-A protein stability through different phases of cell cycle are not well elucidated. Inhibiting the kinase activity and promoting protein degradation are two well-validated conceptual strategies for targeting protein kinases in cancers. Here, we demonstrate that Eukaryotic Elongation Factor 1 Alpha 2 (eEF1A2) facilitates PTEN-GSK3β mediated Aurora-A protein degradation through the SCF complex (SKP1-Cul1-FBXW7) during the S/G2 phase of proliferating cells. In contrast, this mechanism is inactivated in cancer cells accompanying PTEN-GSK3β pathway deficiency. Mechanistically, eEF1A2 interacts with Aurora-A, GSK3β, FBXW7 and Cul1-E3 ligase, as the SCF complex, to facilitate Aurora-A polyubiquitination for 26S proteasomal degradation. eEF1A2 promotes PTEN phosphorylation at T366 and stability, inactivates AKT and activates GSK3β which in turn phosphorylates Aurora-A at S283, S284 and S342. The phosphorylation of Aurora-A at S342 is detected during S/G2 phase of cell mitosis in parallel with eEF1A2-SCF complex formation with active form of GSK3β and neddylated Cul1. Conversely, genetic ablation of EEF1A2 and PTEN, activation of AKT, inhibition of GSK3β, expression of Aurora-A phosphodeficient-mutant attenuates the Aurora-A protein degradation which is corroborated in Aurora-A overexpressing mouse mammary carcinomas and human breast carcinomas. This study identifies a novel mechanism of Aurora-A protein degradation mediated eEF1A2-PTEN-GSK3β pathway and provides a framework for the discovery of Aurora-A therapeutic targets in breast cancer that harbors deficiency of PTEN tumor suppressor pathway.
Citation Format: Treekitkarnmongkol W, Solis LM, Kai K, Thompson AM, Tian W, Wistuba II, Sasai K, Jltsumori Y, Sahin AA, Hawke DH, Lee JM, Qin L, Bawa-Khalfe T, Rad R, Wong KK, Abbott CM, Katayama H, Sen S. eEF1A2 facilitates PTEN-GSK3β mediated Aurora-A protein degradation during S-G2 phase inactivated in PTEN-deficient breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-05-05.
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Affiliation(s)
- W Treekitkarnmongkol
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - LM Solis
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - K Kai
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - AM Thompson
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - W Tian
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - II Wistuba
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - K Sasai
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - Y Jltsumori
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - AA Sahin
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - DH Hawke
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - JM Lee
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - L Qin
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - T Bawa-Khalfe
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - R Rad
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - KK Wong
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - CM Abbott
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - H Katayama
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
| | - S Sen
- The University of Texas M.D. Anderson Cancer Center, Houston, TX; Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; University of Ottawa, Ottawa, ON, Canada; Houston Methodist Research Institute, Houston, TX; University of Houston, Houston, TX; Technische Universität München, München, BY, Germany; University of Edinburgh, Edinburgh, United Kingdom
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13
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McLachlan F, Sires AM, Abbott CM. The role of translation elongation factor eEF1 subunits in neurodevelopmental disorders. Hum Mutat 2018; 40:131-141. [PMID: 30370994 DOI: 10.1002/humu.23677] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 10/16/2018] [Accepted: 10/23/2018] [Indexed: 11/06/2022]
Abstract
The multi-subunit eEF1 complex plays a crucial role in de novo protein synthesis. The central functional component of the complex is eEF1A, which occurs as two independently encoded variants with reciprocal expression patterns: whilst eEF1A1 is widely expressed, eEF1A2 is found only in neurons and muscle. Heterozygous mutations in the gene encoding eEF1A2, EEF1A2, have recently been shown to cause epilepsy, autism, and intellectual disability. The remaining subunits of the eEF1 complex, eEF1Bα, eEF1Bδ, eEF1Bγ, and valyl-tRNA synthetase (VARS), together form the GTP exchange factor for eEF1A and are ubiquitously expressed, in keeping with their housekeeping role. However, mutations in the genes encoding these subunits EEF1B2 (eEF1Bα), EEF1D (eEF1Bδ), and VARS (valyl-tRNA synthetase) have also now been identified as causes of neurodevelopmental disorders. In this review, we describe the mutations identified so far in comparison with the degree of normal variation in each gene, and the predicted consequences of the mutations on the functions of the proteins and their isoforms. We discuss the likely effects of the mutations in the context of the role of protein synthesis in neuronal development.
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Affiliation(s)
- Fiona McLachlan
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, UK
| | - Anna Martinez Sires
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, UK
| | - Catherine M Abbott
- Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, UK
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Shah RR, Cholewa-Waclaw J, Davies FCJ, Paton KM, Chaligne R, Heard E, Abbott CM, Bird AP. Efficient and versatile CRISPR engineering of human neurons in culture to model neurological disorders. Wellcome Open Res 2016; 1:13. [PMID: 27976757 DOI: 10.12688/wellcomeopenres.10011.1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The recent identification of multiple new genetic causes of neurological disorders highlights the need for model systems that give experimental access to the underlying biology. In particular, the ability to couple disease-causing mutations with human neuronal differentiation systems would be beneficial. Gene targeting is a well-known approach for dissecting gene function, but low rates of homologous recombination in somatic cells (including neuronal cells) have traditionally impeded the development of robust cellular models of neurological disorders. Recently, however, CRISPR/Cas9 gene editing technologies have expanded the number of systems within which gene targeting is possible. Here we adopt as a model system LUHMES cells, a commercially available diploid human female mesencephalic cell line that differentiates into homogeneous mature neurons in 1-2 weeks. We describe optimised methods for transfection and selection of neuronal progenitor cells carrying targeted genomic alterations using CRISPR/Cas9 technology. By targeting the endogenous X-linked MECP2 locus, we introduced four independent missense mutations that cause the autism spectrum disorder Rett syndrome and observed the desired genetic structure in 3-26% of selected clones, including gene targeting of the inactive X chromosome. Similar efficiencies were achieved by introducing neurodevelopmental disorder-causing mutations at the autosomal EEF1A2 locus on chromosome 20. Our results indicate that efficiency of genetic "knock-in" is determined by the location of the mutation within the donor DNA molecule. Furthermore, we successfully introduced an mCherry tag at the MECP2 locus to yield a fusion protein, demonstrating that larger insertions are also straightforward in this system. We suggest that our optimised methods for altering the genome of LUHMES cells make them an attractive model for the study of neurogenetic disorders.
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Affiliation(s)
- Ruth R Shah
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
| | | | - Faith C J Davies
- Centre for Genomic and Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, UK
| | - Katie M Paton
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Ronan Chaligne
- Centre de Recherche, Institut Curie, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 3215, Institut National de la Santé et de la Recherche Médicale U934, Paris, France
| | - Edith Heard
- Centre de Recherche, Institut Curie, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 3215, Institut National de la Santé et de la Recherche Médicale U934, Paris, France
| | - Catherine M Abbott
- Centre for Genomic and Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, UK
| | - Adrian P Bird
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
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Lam WWK, Millichap JJ, Soares DC, Chin R, McLellan A, FitzPatrick DR, Elmslie F, Lees MM, Schaefer GB, Abbott CM. Novel de novo EEF1A2 missense mutations causing epilepsy and intellectual disability. Mol Genet Genomic Med 2016; 4:465-74. [PMID: 27441201 PMCID: PMC4947865 DOI: 10.1002/mgg3.219] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 02/12/2016] [Accepted: 02/16/2016] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Exome sequencing has led to the discovery of mutations in novel causative genes for epilepsy. One such gene is EEF1A2, encoding a neuromuscular specific translation elongation factor, which has been found to be mutated de novo in five cases of severe epilepsy. We now report on a further seven cases, each with a different mutation, of which five are newly described. METHODS New cases were identified and sequenced through the Deciphering Developmental Disabilities project, via direct contact with neurologists or geneticists, or recruited via our website. RESULTS All the mutations cause epilepsy and intellectual disability, but with a much wider range of severity than previously identified. All new cases share specific subtle facial dysmorphic features. Each mutation occurs at an evolutionarily highly conserved amino acid position indicating strong structural or functional selective pressure. CONCLUSIONS EEF1A2 should be considered as a causative gene not only in cases of epileptic encephalopathy but also in children with less severe epilepsy and intellectual disability. The emergence of a possible discernible phenotype, a broad nasal bridge, tented upper lip, everted lower lip and downturned corners of the mouth may help in identifying patients with mutations in EEF1A2.
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Affiliation(s)
- Wayne W K Lam
- South East of Scotland Clinical Genetics ServiceCrewe RoadEdinburghUK; Centre for Genomic & Experimental MedicineMRC Institute of Genetics and Molecular MedicineUniversity of EdinburghWestern General HospitalCrewe RoadEdinburghEH4 2XUUK; Muir Maxwell Epilepsy CentreUniversity of Edinburgh20 Sylvan PlaceEdinburghEH9 1UWUK; Paediatric NeurosciencesRoyal Hospital for Sick ChildrenSciennes RoadEdinburghEH9 1LFUK
| | - John J Millichap
- Epilepsy Center Departments of Pediatrics and Neurology Ann & Robert H. Lurie Children's Hospital of Chicago Northwestern University Feinberg School of Medicine 225 E Chicago Ave Box #29 Chicago Illinois 60611
| | - Dinesh C Soares
- Centre for Genomic & Experimental MedicineMRC Institute of Genetics and Molecular MedicineUniversity of EdinburghWestern General HospitalCrewe RoadEdinburghEH4 2XUUK; MRC Human Genetics UnitMRC Institute of Genetics and Molecular MedicineUniversity of EdinburghWestern General HospitalCrewe RoadEdinburghEH4 2XUUK
| | - Richard Chin
- Muir Maxwell Epilepsy CentreUniversity of Edinburgh20 Sylvan PlaceEdinburghEH9 1UWUK; Paediatric NeurosciencesRoyal Hospital for Sick ChildrenSciennes RoadEdinburghEH9 1LFUK; Child Life and HealthUniversity of Edinburgh20 Sylvan PlaceEdinburghEH9 1UWUK
| | - Ailsa McLellan
- Paediatric Neurosciences Royal Hospital for Sick Children Sciennes Road Edinburgh EH9 1LF UK
| | - David R FitzPatrick
- Paediatric NeurosciencesRoyal Hospital for Sick ChildrenSciennes RoadEdinburghEH9 1LFUK; MRC Human Genetics UnitMRC Institute of Genetics and Molecular MedicineUniversity of EdinburghWestern General HospitalCrewe RoadEdinburghEH4 2XUUK
| | - Frances Elmslie
- South West Thames Regional Genetics Service St George's Hospital Tooting London UK
| | - Melissa M Lees
- Department of Clinical Genetics Great Ormond Street Hospital Great Ormond Street London UK
| | - G Bradley Schaefer
- Division of Medical Genetics Arkansas Children's Hospital Little Rock Arkansas
| | | | - Catherine M Abbott
- Centre for Genomic & Experimental MedicineMRC Institute of Genetics and Molecular MedicineUniversity of EdinburghWestern General HospitalCrewe RoadEdinburghEH4 2XUUK; Muir Maxwell Epilepsy CentreUniversity of Edinburgh20 Sylvan PlaceEdinburghEH9 1UWUK
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Li D, Wei T, Rawle DJ, Qin F, Wang R, Soares DC, Jin H, Sivakumaran H, Lin MH, Spann K, Abbott CM, Harrich D. Specific Interaction between eEF1A and HIV RT Is Critical for HIV-1 Reverse Transcription and a Potential Anti-HIV Target. PLoS Pathog 2015; 11:e1005289. [PMID: 26624286 PMCID: PMC4666417 DOI: 10.1371/journal.ppat.1005289] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 10/30/2015] [Indexed: 11/19/2022] Open
Abstract
Reverse transcription is the central defining feature of HIV-1 replication. We previously reported that the cellular eukaryotic elongation factor 1 (eEF1) complex associates with the HIV-1 reverse transcription complex (RTC) and the association is important for late steps of reverse transcription. Here we show that association between the eEF1 and RTC complexes occurs by a strong and direct interaction between the subunit eEF1A and reverse transcriptase (RT). Using biolayer interferometry and co-immunoprecipitation (co-IP) assays, we show that association between the eEF1 and RTC complexes occurs by a strong (KD ~3–4 nM) and direct interaction between eEF1A and reverse transcriptase (RT). Biolayer interferometry analysis of cell lysates with titrated levels of eEF1A indicates it is a predominant cellular RT binding protein. Both the RT thumb and connection domains are required for interaction with eEF1A. A single amino acid mutation, W252A, within the thumb domain impaired co-IP between eEF1A and RT, and also significantly reduced the efficiency of late reverse transcription and virus replication when incorporated into infectious HIV-1. Molecular modeling analysis indicated that interaction between W252 and L303 are important for RT structure, and their mutation to alanine did not impair heterodimerisation, but negatively impacted interaction with eEF1A. Didemnin B, which specifically binds eEF1A, potently inhibited HIV-1 reverse transcription by greater than 2 logs at subnanomolar concentrations, especially affecting reverse transcription late DNA synthesis. Analysis showed reduced levels of RTCs from HIV-1-infected HEK293T treated with didemnin B compared to untreated cells. Interestingly, HIV-1 with a W252A RT mutation was resistant to didemnin B negative effects showing that didemnin B affects HIV-1 by targeting the RT-eEF1A interaction. The combined evidence indicates a direct interaction between eEF1A and RT is crucial for HIV reverse transcription and replication, and the RT-eEF1A interaction is a potential drug target. After infecting a target cell, HIV-1 like all retroviruses converts the viral single strand RNA genome into double strand DNA by the process called reverse transcription. Host proteins are known to be important for reverse transcription yet a direct role for any host protein has not been demonstrated. In this paper, we show that a eukaryotic translation elongation factor (eEF1A), an abundant cellular protein, directly and strongly binds to the viral enzyme reverse transcriptase (RT). The biological relevance of the association is supported by mutational analysis of RT and by treating cells with the small molecule didemnin B that specifically binds eEF1A. Mutation of RT or treatment of cells with didemnin B resulted in significantly decreased efficiency of reverse transcription. Didemnin B treatment of cells disrupted HIV-1’s ability to maintain the viral machinery necessary for reverse transcription. However, an HIV-1 mutant, which does not interact with eEF1A, was resistant to didemnin B negative effects on early viral replication, showing that didemnin B affects HIV-1 by targeting the RT-eEF1A interaction. Altogether, this study demonstrates that eEF1A is an integral component of the viral reverse transcription complex and that the RT-eEF1A interaction is a possible new drug target to inhibit HIV-1 replication.
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Affiliation(s)
- Dongsheng Li
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Ting Wei
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Daniel J. Rawle
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
- School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Queensland, Australia
| | - Fangyun Qin
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Rui Wang
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Dinesh C. Soares
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh, United Kingdom
| | - Hongping Jin
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Haran Sivakumaran
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Min-Hsuan Lin
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Kirsten Spann
- School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Queensland, Australia
- School of Biomedical Science, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Catherine M. Abbott
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, MRC Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh, United Kingdom
| | - David Harrich
- Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
- * E-mail:
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Vera M, Pani B, Griffiths LA, Muchardt C, Abbott CM, Singer RH, Nudler E. The translation elongation factor eEF1A1 couples transcription to translation during heat shock response. eLife 2014; 3:e03164. [PMID: 25233275 PMCID: PMC4164936 DOI: 10.7554/elife.03164] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 08/14/2014] [Indexed: 01/26/2023] Open
Abstract
Translation elongation factor eEF1A has a well-defined role in protein synthesis. In this study, we demonstrate a new role for eEF1A: it participates in the entire process of the heat shock response (HSR) in mammalian cells from transcription through translation. Upon stress, isoform 1 of eEF1A rapidly activates transcription of HSP70 by recruiting the master regulator HSF1 to its promoter. eEF1A1 then associates with elongating RNA polymerase II and the 3′UTR of HSP70 mRNA, stabilizing it and facilitating its transport from the nucleus to active ribosomes. eEF1A1-depleted cells exhibit severely impaired HSR and compromised thermotolerance. In contrast, tissue-specific isoform 2 of eEF1A does not support HSR. By adjusting transcriptional yield to translational needs, eEF1A1 renders HSR rapid, robust, and highly selective; thus, representing an attractive therapeutic target for numerous conditions associated with disrupted protein homeostasis, ranging from neurodegeneration to cancer. DOI:http://dx.doi.org/10.7554/eLife.03164.001 Living cells must be able to withstand changes in the environment. For example, if there is a sudden increase in temperature—which could damage proteins or other molecules—most cells can respond with the ‘heat shock response’. In humans and other mammals, a single protein called heat shock factor 1 triggers the production of numerous heat shock proteins that protect the cell from the detrimental effects of high temperatures. Most heat shock proteins protect cells by binding to, and stabilizing, other molecules in the cell; this prevents these molecules from being damaged or from aggregating and allows them to continue to function as normal. A protein called eEF1A1 is involved in the final stages of protein production and also enhances the function of heat shock factor 1 during the heat shock response. To make a protein, an enzyme called RNA polymerase transcribes DNA in the nucleus of the cell into a messenger RNA molecule that then exits the nucleus and binds to a ribosome. This molecular machine then translates the messenger RNA sequence into a protein by joining together individual building blocks called amino acids in the correct order. Like other elongation factors, eEF1A1 helps to select the amino acids that match the sequence of the messenger RNA template. However, it was unclear how eEF1A1 helped to protect cells during the heat shock response. Nudler et al. have now engineered cells—from humans and mice—that make less of the eEF1A1 protein than normal. These cells had enough of this protein to support their growth and development under normal conditions, but not enough to help during the heat shock response. When these cells are subjected to a sudden increase in temperature, they fail to produce a sufficient amount of major heat shock proteins. Heat shock factor 1 is needed to transcribe the genes that encode these heat shock proteins, and Nudler et al. found that eEF1A1 must bind to heat shock factor 1 and then to a moving RNA polymerase for these genes to be transcribed efficiently. Moreover, the eEF1A1 protein was shown to bind to and stabilize the heat shock proteins' messenger RNAs, and aid their export from the nucleus and their binding to the ribosome. These newly discovered roles for eEF1A1 during the heat shock response highlight this elongation factor as a promising drug target for treating diseases where protein folding goes awry, for example in Alzheimer's or Parkinson's disease. In adults, neurons do not make enough eEF1A1, and Nudler et al. suggest that enabling these cells to make more of this protein could help to treat a range of neurodegenerative conditions. DOI:http://dx.doi.org/10.7554/eLife.03164.002
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Affiliation(s)
- Maria Vera
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, United States
| | - Bibhusita Pani
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, United States
| | - Lowri A Griffiths
- Medical Genetics Section, Molecular Medicine Centre, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh, United Kingdom
| | - Christian Muchardt
- Département de Biologie du Développement et Cellules Souches, Institut Pasteur, CNRS URA2578, Paris, France
| | - Catherine M Abbott
- Medical Genetics Section, Molecular Medicine Centre, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Edinburgh, United Kingdom
| | - Robert H Singer
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, United States
| | - Evgeny Nudler
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, United States
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Doig J, Griffiths LA, Peberdy D, Dharmasaroja P, Vera M, Davies FJC, Newbery HJ, Brownstein D, Abbott CM. In vivo characterization of the role of tissue-specific translation elongation factor 1A2 in protein synthesis reveals insights into muscle atrophy. FEBS J 2014; 280:6528-40. [PMID: 24460877 PMCID: PMC4163635 DOI: 10.1111/febs.12554] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Translation elongation factor 1A2 (eEF1A2), uniquely among translation factors, is expressed specifically in neurons and muscle. eEF1A2‐null mutant wasted mice develop an aggressive, early‐onset form of neurodegeneration, but it is unknown whether the wasting results from denervation of the muscles, or whether the mice have a primary myopathy resulting from loss of translation activity in muscle. We set out to establish the relative contributions of loss of eEF1A2 in the different tissues to this postnatal lethal phenotype. We used tissue‐specific transgenesis to show that correction of eEF1A2 levels in muscle fails to ameliorate the overt phenotypic abnormalities or time of death of wasted mice. Molecular markers of muscle atrophy such as Fbxo32 were dramatically upregulated at the RNA level in wasted mice, both in the presence and in the absence of muscle‐specific expression of eEF1A2, but the degree of upregulation at the protein level was significantly lower in those wasted mice without transgene‐derived expression of eEF1A2 in muscle. This provides the first in vivo confirmation that eEF1A2 plays an important role in translation. In spite of the inability of the nontransgenic wasted mice to upregulate key atrogenes at the protein level in response to denervation to the same degree as their transgenic counterparts, there were no measurable differences between transgenic and nontransgenic wasted mice in terms of weight loss, grip strength, or muscle pathology. This suggests that a compromised ability fully to execute the atrogene pathway in denervated muscle does not affect the process of muscle atrophy in the short term.
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Affiliation(s)
- Jennifer Doig
- Medical Genetics Section, Molecular Medicine Centre, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, UK
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Soares DC, Abbott CM. Highly homologous eEF1A1 and eEF1A2 exhibit differential post-translational modification with significant enrichment around localised sites of sequence variation. Biol Direct 2013; 8:29. [PMID: 24220286 PMCID: PMC3868327 DOI: 10.1186/1745-6150-8-29] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 11/11/2013] [Indexed: 12/21/2022] Open
Abstract
REVIEWERS This article was reviewed by Frank Eisenhaber and Ramanathan Sowdhamini.Translation elongation factors eEF1A1 and eEF1A2 are 92% identical but exhibit non-overlapping expression patterns. While the two proteins are predicted to have similar tertiary structures, it is notable that the minor variations between their sequences are highly localised within their modelled structures. We used recently available high-throughput "omics" data to assess the spatial location of post-translational modifications and discovered that they are highly enriched on those surface regions of the protein that correspond to the clusters of sequence variation. This observation suggests how these two isoforms could be differentially regulated allowing them to perform distinct functions.
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Griffiths LA, Doig J, Churchhouse AMD, Davies FCJ, Squires CE, Newbery HJ, Abbott CM. Haploinsufficiency for translation elongation factor eEF1A2 in aged mouse muscle and neurons is compatible with normal function. PLoS One 2012; 7:e41917. [PMID: 22848658 PMCID: PMC3405021 DOI: 10.1371/journal.pone.0041917] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Accepted: 06/28/2012] [Indexed: 11/19/2022] Open
Abstract
Translation elongation factor isoform eEF1A2 is expressed in muscle and neurons. Deletion of eEF1A2 in mice gives rise to the neurodegenerative phenotype "wasted" (wst). Mice homozygous for the wasted mutation die of muscle wasting and neurodegeneration at four weeks post-natal. Although the mutation is said to be recessive, aged heterozygous mice have never been examined in detail; a number of other mouse models of motor neuron degeneration have recently been shown to have similar, albeit less severe, phenotypic abnormalities in the heterozygous state. We therefore examined the effects of ageing on a cohort of heterozygous +/wst mice and control mice, in order to establish whether a presumed 50% reduction in eEF1A2 expression was compatible with normal function. We evaluated the grip strength assay as a way of distinguishing between wasted and wild-type mice at 3-4 weeks, and then performed the same assay in older +/wst and wild-type mice. We also used rotarod performance and immunohistochemistry of spinal cord sections to evaluate the phenotype of aged heterozygous mice. Heterozygous mutant mice showed no deficit in neuromuscular function or signs of spinal cord pathology, in spite of the low levels of eEF1A2.
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Affiliation(s)
- Lowri A. Griffiths
- Centre for Molecular Medicine, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Jennifer Doig
- Centre for Molecular Medicine, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Antonia M. D. Churchhouse
- Centre for Molecular Medicine, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Faith C. J. Davies
- Centre for Molecular Medicine, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Charlotte E. Squires
- Centre for Molecular Medicine, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Helen J. Newbery
- Centre for Molecular Medicine, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Catherine M. Abbott
- Centre for Molecular Medicine, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
- * E-mail:
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Newbery HJ, Stancheva I, Zimmerman LB, Abbott CM. Evolutionary importance of translation elongation factor eEF1A variant switching: eEF1A1 down-regulation in muscle is conserved in Xenopus but is controlled at a post-transcriptional level. Biochem Biophys Res Commun 2011; 411:19-24. [DOI: 10.1016/j.bbrc.2011.06.062] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Accepted: 06/08/2011] [Indexed: 11/15/2022]
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Kanibolotsky DS, Novosyl'na OV, Abbott CM, Negrutskii BS, El'skaya AV. Multiple molecular dynamics simulation of the isoforms of human translation elongation factor 1A reveals reversible fluctuations between "open" and "closed" conformations and suggests specific for eEF1A1 affinity for Ca2+-calmodulin. BMC Struct Biol 2008; 8:4. [PMID: 18221514 PMCID: PMC2275276 DOI: 10.1186/1472-6807-8-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Accepted: 01/25/2008] [Indexed: 11/26/2022]
Abstract
BACKGROUND Eukaryotic translation elongation factor eEF1A directs the correct aminoacyl-tRNA to ribosomal A-site. In addition, eEF1A is involved in carcinogenesis and apoptosis and can interact with large number of non-translational ligands. There are two isoforms of eEF1A, which are 98% similar. Despite the strong similarity, the isoforms differ in some properties. Importantly, the appearance of eEF1A2 in tissues in which the variant is not normally expressed can be coupled to cancer development.We reasoned that the background for the functional difference of eEF1A1 and eEF1A2 might lie in changes of dynamics of the isoforms. RESULTS It has been determined by multiple MD simulation that eEF1A1 shows increased reciprocal flexibility of structural domains I and II and less average distance between the domains, while increased non-correlated diffusive atom motions within protein domains characterize eEF1A2. The divergence in the dynamic properties of eEF1A1 and eEF1A2 is caused by interactions of amino acid residues that differ between the two variants with neighboring residues and water environment. The main correlated motion of both protein isoforms is the change in proximity of domains I and II which can lead to disappearance of the gap between the domains and transition of the protein into a "closed" conformation. Such a transition is reversible and the protein can adopt an "open" conformation again. This finding is in line with our earlier experimental observation that the transition between "open" and "closed" conformations of eEF1A could be essential for binding of tRNA and/or other biological ligands. The putative calmodulin-binding region Asn311-Gly327 is less flexible in eEF1A1 implying its increased affinity for calmodulin. The ability of eEF1A1 rather than eEF1A2 to interact with Ca2+/calmodulin is shown experimentally in an ELISA-based test. CONCLUSION We have found that reversible transitions between "open" and "close" conformations of eEF1A provide a molecular background for the earlier observation that the eEF1A molecule is able to change the shape upon interaction with tRNA. The ability of eEF1A1 rather than eEF1A2 to interact with calmodulin is predicted by MD analysis and showed experimentally. The differential ability of the eEF1A isoforms to interact with signaling molecules discovered in this study could be associated with cancer-related properties of eEF1A2.
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Affiliation(s)
- Dmitry S Kanibolotsky
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, 150 Academician Zabolotny Street, 03680 Kiev, Ukraine
- National Taras Shevchenko University of Kiev, 64 Volodymyrska Street, 01033 Kiev, Ukraine
| | - Oleksandra V Novosyl'na
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, 150 Academician Zabolotny Street, 03680 Kiev, Ukraine
| | - Catherine M Abbott
- Medical Genetics, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Boris S Negrutskii
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, 150 Academician Zabolotny Street, 03680 Kiev, Ukraine
| | - Anna V El'skaya
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, 150 Academician Zabolotny Street, 03680 Kiev, Ukraine
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Newbery HJ, Loh DH, O'Donoghue JE, Tomlinson VAL, Chau YY, Boyd JA, Bergmann JH, Brownstein D, Abbott CM. Translation elongation factor eEF1A2 is essential for post-weaning survival in mice. J Biol Chem 2007; 282:28951-28959. [PMID: 17640869 DOI: 10.1074/jbc.m703962200] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Translation elongation factor eEF1A, formerly known as EF-1 alpha, exists as two variant forms; eEF1A1, which is almost ubiquitously expressed, and eEF1A2, whose expression is restricted to muscle and brain at the level of whole tissues. Expression analysis of these genes has been complicated by a general lack of availability of antibodies that specifically recognize each variant form. Wasted mice (wst/wst) have a 15.8-kilobase deletion that abolishes activity of eEF1A2, but before this study it was unknown whether the deletion also affected neighboring genes. We have generated a panel of anti-peptide antibodies and used them to show that eEF1A2 is expressed at high levels in specific cell types in tissues previously thought not to express this variant, such as pancreatic islet cells and enteroendocrine cells in colon crypts. Expression of eEF1A1 and eEF1A2 is shown to be generally mutually exclusive, and we relate the expression pattern of eEF1A2 to the phenotype seen in wasted mice. We then carried out a series of transgenic experiments to establish whether the expression of other genes is affected by the deletion in wasted mice. We show that aspects of the phenotype such as motor neuron degeneration relate precisely to the relative expression of eEF1A1 and eEF1A2, whereas the immune system abnormalities are likely to result from a stress response. We conclude that loss of eEF1A2 function is solely responsible for the abnormalities seen in these mice.
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Affiliation(s)
- H J Newbery
- Medical Genetics, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom and
| | - D H Loh
- Medical Genetics, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom and
| | - J E O'Donoghue
- Medical Genetics, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom and
| | - V A L Tomlinson
- Medical Genetics, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom and
| | - Y-Y Chau
- Medical Genetics, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom and
| | - J A Boyd
- Medical Genetics, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom and
| | - J H Bergmann
- Medical Genetics, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom and
| | - D Brownstein
- Research Animal Pathology Core Facility, Room W3.03, Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, United Kingdom
| | - C M Abbott
- Medical Genetics, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, United Kingdom and.
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Tomlinson VAL, Newbery HJ, Bergmann JH, Boyd J, Scott D, Wray NR, Sellar GC, Gabra H, Graham A, Williams ARW, Abbott CM. Expression of eEF1A2 is associated with clear cell histology in ovarian carcinomas: overexpression of the gene is not dependent on modifications at the EEF1A2 locus. Br J Cancer 2007; 96:1613-20. [PMID: 17437010 PMCID: PMC2359942 DOI: 10.1038/sj.bjc.6603748] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The tissue-specific translation elongation factor eEF1A2 is a potential oncogene that is overexpressed in human ovarian cancer. eEF1A2 is highly similar (98%) to the near-ubiquitously expressed eEF1A1 (formerly known as EF1-α) making analysis with commercial antibodies difficult. We wanted to establish the expression pattern of eEF1A2 in ovarian cancer of defined histological subtypes at both the RNA and protein level, and to establish the mechanism for the overexpression of eEF1A2 in tumours. We show that while overexpression of eEF1A2 is seen at both the RNA and protein level in up to 75% of clear cell carcinomas, it occurs at a lower frequency in other histological subtypes. The copy number at the EEF1A2 locus does not correlate with expression level of the gene, no functional mutations were found, and the gene is unmethylated in both normal and tumour DNA, showing that overexpression is not dependent on genetic or epigenetic modifications at the EEF1A2 locus. We suggest that the cause of overexpression of eEF1A2 may be the inappropriate expression of a trans-acting factor. The oncogenicity of eEF1A2 may be related either to its role in protein synthesis or to potential non-canonical functions.
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Affiliation(s)
- V A L Tomlinson
- Medical Genetics, School of Molecular and Clinical Medicine, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh EH4 2XU, UK
| | - H J Newbery
- Medical Genetics, School of Molecular and Clinical Medicine, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh EH4 2XU, UK
| | - J H Bergmann
- Medical Genetics, School of Molecular and Clinical Medicine, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh EH4 2XU, UK
| | - J Boyd
- Medical Genetics, School of Molecular and Clinical Medicine, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh EH4 2XU, UK
| | - D Scott
- Cancer Research UK, Edinburgh Oncology Unit, University of Edinburgh Cancer Research Centre, Edinburgh EH4 2XR, UK
| | - N R Wray
- Medical Genetics, School of Molecular and Clinical Medicine, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh EH4 2XU, UK
| | - G C Sellar
- Cancer Research UK, Edinburgh Oncology Unit, University of Edinburgh Cancer Research Centre, Edinburgh EH4 2XR, UK
| | - H Gabra
- Cancer Research UK, Edinburgh Oncology Unit, University of Edinburgh Cancer Research Centre, Edinburgh EH4 2XR, UK
| | - A Graham
- Division of Pathology, University of Edinburgh, Royal Infirmary, Little France, Edinburgh EH4 2XR, UK
| | - A R W Williams
- Division of Pathology, University of Edinburgh, Royal Infirmary, Little France, Edinburgh EH4 2XR, UK
| | - C M Abbott
- Medical Genetics, School of Molecular and Clinical Medicine, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh EH4 2XU, UK
- E-mail:
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25
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Tomlinson VAL, Newbery HJ, Wray NR, Jackson J, Larionov A, Miller WR, Dixon JM, Abbott CM. Translation elongation factor eEF1A2 is a potential oncoprotein that is overexpressed in two-thirds of breast tumours. BMC Cancer 2005; 5:113. [PMID: 16156888 PMCID: PMC1236916 DOI: 10.1186/1471-2407-5-113] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2005] [Accepted: 09/12/2005] [Indexed: 11/11/2022] Open
Abstract
Background The tissue-specific translation elongation factor eEF1A2 was recently shown to be a potential oncogene that is overexpressed in ovarian cancer. Although there is no direct evidence for an involvement of eEF1A2 in breast cancer, the genomic region to which EEF1A2 maps, 20q13, is frequently amplified in breast tumours. We therefore sought to establish whether eEF1A2 expression might be upregulated in breast cancer. Methods eEF1A2 is highly similar (98%) to the near-ubiquitously expressed eEF1A1 (formerly known as EF1-α) making analysis with commercial antibodies difficult. We have developed specific anti-eEF1A2 antibodies and used them in immunohistochemical analyses of tumour samples. We report the novel finding that although eEF1A2 is barely detectable in normal breast it is moderately to strongly expressed in two-thirds of breast tumours. This overexpression is strongly associated with estrogen receptor positivity. Conclusion eEF1A2 should be considered as a putative oncogene in breast cancer that may be a useful diagnostic marker and therapeutic target for a high proportion of breast tumours. The oncogenicity of eEF1A2 may be related to its role in protein synthesis or to its potential non-canonical functions in cytoskeletal remodelling or apoptosis.
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Affiliation(s)
- Victoria AL Tomlinson
- Medical Genetics, School of Molecular and Clinical Medicine, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Helen J Newbery
- Medical Genetics, School of Molecular and Clinical Medicine, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Naomi R Wray
- Medical Genetics, School of Molecular and Clinical Medicine, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Juliette Jackson
- Breast Unit Research Group, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Alexey Larionov
- Breast Unit Research Group, Western General Hospital, Edinburgh EH4 2XU, UK
| | - William R Miller
- Breast Unit Research Group, Western General Hospital, Edinburgh EH4 2XU, UK
| | - J Michael Dixon
- Breast Unit Research Group, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Catherine M Abbott
- Medical Genetics, School of Molecular and Clinical Medicine, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh EH4 2XU, UK
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26
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Newbery HJ, Gillingwater TH, Dharmasaroja P, Peters J, Wharton SB, Thomson D, Ribchester RR, Abbott CM. Progressive Loss of Motor Neuron Function in Wasted Mice: Effects of a Spontaneous Null Mutation in the Gene for the eEF1A2 Translation Factor. J Neuropathol Exp Neurol 2005; 64:295-303. [PMID: 15835265 DOI: 10.1093/jnen/64.4.295] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Wasted (wst) is a spontaneous autosomal recessive mutation in which the gene encoding translation factor eEF1A2 is deleted. Homozygous mice show tremors and disturbances of gait shortly after weaning, followed by motor neuron degeneration, paralysis, and death by about 28 days. We have now conducted a more detailed analysis of neuromuscular pathology in these animals. Reactive gliosis was observed at 19 days postnatal in wst/wst cervical spinal cord, showing a rostrocaudal gradient. This was followed a few days later by motor neuron vacuolation and neurofilament accumulation, again with a rostrocaudal progression. Thoracic/abdominal muscles from wst/wst mice aged 17 days showed evidence of progressive denervation of motor endplates, including weak synaptic transmission and retraction of motor nerve terminals. Similar abnormalities appeared in distal, lumbrical muscles from about 25 days of age. We conclude that spontaneous failure of eEF1A2 expression in the wasted mutant first triggers gliosis in spinal cord and retraction of motor nerve terminals in muscle, and then motor neuron pathology and death. The early initiation and rapid progression of motor unit degeneration in wst/wst mice suggest that they should be considered an important and accessible model of early-onset motor neuron degeneration in humans.
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Affiliation(s)
- Helen J Newbery
- Medical Genetics, Molecular Medicine Center, University of Edinburgh, Western General Hospital, Edinburgh, UK
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Abstract
A high proportion of LT/Sv strain oocytes arrest in meiotic metaphase I (MI) and are ovulated as diploid primary oocytes rather than haploid secondary oocytes. (Mus musculus castaneus x LT/SvKau)F1 x LT/SvKau backcross females were analysed for the proportion of oocytes that arrested in MI and typed by PCR for a panel of microsatellite DNA sequences (simple sequence repeat polymorphisms) that differed between strain LT/SvKau and M. m. castaneus. This provided a whole genome scan of 86 genetic markers distributed over all 19 autosomes and the X chromosome, and revealed genetic linkage of the MI arrest phenotype to markers on chromosomes 1 and 9. Identification of these two chromosomal regions should facilitate the identification of genes involved in mammalian oocyte maturation and the control of meiosis.
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Affiliation(s)
- Clare A Everett
- Medical Genetics, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
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28
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Abstract
It has been known for many years that aberrant levels of the factors involved in translation of mRNA can contribute to disease, most notably cancer. However, despite the wealth of information gathered about initiation and elongation factors from biochemical studies in mammalian cells, and from mutation analysis in lower organisms, little was known until recently about the effects that mutations in these factors could have on cellular function in higher organisms. In the past few years, this balance has started to be redressed, and we are at a fascinating stage in the molecular pathology of translation factors. It has been discovered recently that mutations in subunits of eukaryotic initiation factor 2B (eIF2B) underlie the neurodegenerative disease termed 'vanishing white matter'.
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Affiliation(s)
- Catherine M Abbott
- Medical Genetics, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh, EH4 2XU, UK.
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29
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Nürnberger B, Hofman S, Förg-Brey B, Praetzel G, Maclean A, Szymura JM, Abbott CM, Barton NH. A linkage map for the hybridising toads Bombina bombina and B. variegata (Anura: Discoglossidae). Heredity (Edinb) 2003; 91:136-42. [PMID: 12886280 DOI: 10.1038/sj.hdy.6800291] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Stable hybrid zones in which ecologically divergent taxa give rise to a range of recombinants are natural laboratories in which the genetic basis of adaptation and reproductive isolation can be unraveled. One such hybrid zone is formed by the fire-bellied toads Bombina bombina and B. variegata (Anura: Discoglossidae). Adaptations to permanent and ephemeral breeding habitats, respectively, have shaped numerous phenotypic differences between the taxa. All of these are, in principle, candidates for a genetic dissection via QTL mapping. We present here a linkage map of 28 codominant and 10 dominant markers in the Bombina genome. In an F2 cross, markers that were mainly microsatellites, SSCPs or allozymes were mapped to 20 linkage groups. Among the 40 isolated CA microsatellites, we noted a preponderance of compound and frequently interleaved CA-TA repeats as well as a striking polarity at the 5' end of the repeats.
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Affiliation(s)
- B Nürnberger
- Department Biologie II, Ludwig-Maximilians-Universität, Karlstr. 23-25, 80333 München, Germany.
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30
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Abstract
The use of mouse models has been of particular importance in studying the pathogenesis of amyotrophic lateral sclerosis. Here, we describe both transgenic and classical mutants for which the genetic lesion is known. We draw attention, wherever possible, to pathological factors common to multiple models.
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Affiliation(s)
- Helen J Newbery
- Medical Genetics Section, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh, UK EH4 2XU
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31
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Chambers DM, Rouleau GA, Abbott CM. Comparative genomic analysis of genes encoding translation elongation factor 1B(alpha) in human and mouse shows EEF1B1 to be a recent retrotransposition event. Genomics 2001; 77:145-8. [PMID: 11597139 DOI: 10.1006/geno.2001.6626] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have characterized genomic loci encoding translation elongation factor 1B(alpha) (eEF1B(alpha)) in mice and humans. Mice have a single structural locus (named Eef1b2) spanning six exons, which is ubiquitously expressed and maps close to Casp8 on mouse chromosome 1, and a processed pseudogene. Humans have a single intron-containing locus, EEF1B2, which maps to 2q33, and an intronless paralogue expressed only in brain and muscle (EEF1B3). Another locus described previously, EEF1B1, is actually a processed pseudogene on chromosome 15 corresponding to an alternative splice form of EEF1B2. Our study illustrates the value of comparative mapping in distinguishing between processed pseudogenes and intronless paralogues.
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Affiliation(s)
- D M Chambers
- Medical Genetics Section, Department of Medical Sciences, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
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32
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Abstract
The use of mouse models has been of particular importance in studying the pathogenesis of amyotrophic lateral sclerosis. Here, we describe both transgenic and classical mutants for which the genetic lesion is known. We draw attention, wherever possible, to pathological factors common to multiple models.
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Affiliation(s)
- H J Newbery
- Medical Genetics Section, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, EH4 2XU., Edinburgh, UK
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33
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Abstract
The expansion of normally polymorphic CTG microsatellites in certain human genes has been identified as the causative mutation of a number of hereditary neurological disorders, including Huntington's disease and myotonic dystrophy. Here, we have investigated the effect of methyl-directed mismatch repair (MMR) on the stability of a (CTG)43 repeat in Escherichia coli over 140 generations and find two opposing effects. In contrast to orientation-dependent repeat instability in wild-type E. coli and yeast, we observed no orientation dependence in MMR- E. coli cells and suggest that, for the repeat that we have studied, orientation dependence in wild-type cells is mainly caused by functional mismatch repair genes. Our results imply that slipped structures are generated during replication, causing single triplet expansions and contractions in MMR- cells, because they are left unrepaired. On the other hand, we find that the repair of such slipped structures by the MMR system can go awry, resulting in large contractions. We show that these mutS-dependent contractions arise preferentially when the CTG sequence is encoded by the lagging strand. The nature of this orientation dependence argues that the small slipped structures that are recognized by the MMR system are formed primarily on the lagging strand of the replication fork. It also suggests that, in the presence of functional MMR, removal of 3 bp slipped structures causes the formation of larger contractions that are probably the result of secondary structure formation by the CTG sequence. We rationalize the opposing effects of MMR on repeat tract stability with a model that accounts for CTG repeat instability and loss of orientation dependence in MMR- cells. Our work resolves a contradiction between opposing claims in the literature of both stabilizing and destabilizing effects of MMR on CTG repeat instability in E. coli.
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Affiliation(s)
- K H Schmidt
- Institute of Cell and Molecular Biology, University of Edinburgh, King's Buildings, Edinburgh EH9 3JR, UK
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34
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Llor X, Serfas MS, Bie W, Vasioukhin V, Polonskaia M, Derry J, Abbott CM, Tyner AL. BRK/Sik expression in the gastrointestinal tract and in colon tumors. Clin Cancer Res 1999; 5:1767-77. [PMID: 10430081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Clones encoding the breast tumor kinase BRK were isolated from a normal human small intestinal cDNA library that was screened with the cDNA encoding the mouse epithelial-specific tyrosine kinase Sik. Although BRK and Sik share only 80% amino acid sequence identity, Southern blot hybridizations confirmed that the two proteins are orthologues. Sik was mapped to mouse distal chromosome 2, which shows conservation of synteny with human chromosome 20q13.3, the location of the BRK gene. BRK expression was examined in the normal gastrointestinal tract, colon tumor cell lines, and primary colon tumor samples. Like Sik, BRK is expressed in normal epithelial cells of the gastrointestinal tract that are undergoing terminal differentiation. BRK expression also increased during differentiation of the Caco-2 colon adenocarcinoma cell line. Modest increases in BRK expression were detected in primary colon tumors by RNase protection, in situ hybridization, and immunohistochemical assays. The BRK tyrosine kinase appears to play a role in signal transduction in the normal gastrointestinal tract, and its overexpression may be linked to the development of a variety of epithelial tumors.
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Affiliation(s)
- X Llor
- Department of Molecular Genetics, University of Illinois College of Medicine, Chicago 60607, USA
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35
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Chambers DM, Kipling D, Abbott CM. Isolation of a microsatellite that reveals paralogy between the subtelomeric regions of mouse chromosomes 17 and 19: further evidence for telomere-telomere exchange in the mouse. Genomics 1998; 53:113-4. [PMID: 9787084 DOI: 10.1006/geno.1998.5477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- D M Chambers
- Molecular Medicine Centre, University of Edinburgh, Edinburgh, EH4 2XU, United Kingdom
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36
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Durkin ME, Albrechtsen R, Chambers DM, Abbott CM, Wewer UM. Evaluation of Lama5 as a candidate for the mouse ragged (Ra) mutation. Biochem Biophys Res Commun 1998; 250:125-30. [PMID: 9735344 DOI: 10.1006/bbrc.1998.9285] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The laminin alpha5 chain is a component of the basement membranes of many developing and adult tissues. The mouse laminin alpha5 chain gene (Lama5) has been mapped close to the locus of the semidominant ragged (Ra) mutation on distal chromosome 2. The cause of the Ra mutation, which is usually lethal in the homozygous state, has not been determined. We have investigated whether a defect in Lama5 is responsible for the ragged mutation, using the RaJ strain. No differences in the level of the laminin alpha5 chain transcript were found in placental RNA from homozygous RaJ mutant embryos compared to normal littermates. Antiserum raised against a recombinant laminin alpha5 chain polypeptide stained the basement membranes of both normal and homozygous mutant embryos to a similar extent. More precise mapping of Lama5 on an interspecific Ra backcross indicated that Lama5 is proximal to the Ra locus. These results exclude Lama5 as a candidate gene for the Ra mutation.
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Affiliation(s)
- M E Durkin
- Institute of Molecular Pathology, University of Copenhagen, Copenhagen, DK-2100, Denmark
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37
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Affiliation(s)
- J Peters
- Mammalian Genetics Unit, Medical Research Council, Didcot, Oxon OX11 0RD, UK
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38
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Chambers DM, Peters J, Abbott CM. The lethal mutation of the mouse wasted (wst) is a deletion that abolishes expression of a tissue-specific isoform of translation elongation factor 1alpha, encoded by the Eef1a2 gene. Proc Natl Acad Sci U S A 1998; 95:4463-8. [PMID: 9539760 PMCID: PMC22512 DOI: 10.1073/pnas.95.8.4463] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
We have identified the mutation responsible for the autosomal recessive wasted (wst) mutation of the mouse. Wasted mice are characterized by wasting and neurological and immunological abnormalities starting at 21 days after birth; they die by 28 days. A deletion of 15.8 kb in wasted mice abolishes expression of a gene called Eef1a2, encoding a protein that is 92% identical at the amino acid level to the translation elongation factor EF1alpha (locus Eef1a). We have found no evidence for the involvement of another gene in this deletion. Expression of Eef1a2 is reciprocal with that of Eef1a. Expression of Eef1a2 takes over from Eef1a in heart and muscle at precisely the time at which the wasted phenotype becomes manifest. These data suggest that there are tissue-specific forms of the translation elongation apparatus essential for postnatal survival in the mouse.
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Affiliation(s)
- D M Chambers
- Human Genetics Unit, Department of Medicine, University of Edinburgh, Molecular Medicine Centre, Western General Hospital, Edinburgh EH4 2XU, United Kingdom
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39
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Alfred JB, Rance K, Taylor BA, Phillips SJ, Abbott CM, Jackson IJ. Mapping in the region of Danforth's short tail and the localization of tail length modifiers. Genome Res 1997; 7:108-17. [PMID: 9049629 DOI: 10.1101/gr.7.2.108] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We have used an interspecific backcross to generate a detailed genetic map around the mouse tail and kidney developmental mutation Danforth's short tail (Sd). The map includes 14 simple sequence repeat (SSR) markers and four genes in a 5-cM region encompassing Sd. In addition we have used a DNA pooling approach to carry out a genome scan to localize quantitative trait loci (QTL) that modify the tail length of Sd progeny of the backcross. This has allowed us to identify a major QTL on chromosome 10 in the region of nodal and three other putative tail length QTL on chromosomes 1, 9, and 18.
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MESH Headings
- Alleles
- Animals
- Chromosome Mapping
- Chromosomes, Human, Pair 1/genetics
- Chromosomes, Human, Pair 10/genetics
- Chromosomes, Human, Pair 18/genetics
- Chromosomes, Human, Pair 9/genetics
- Female
- Genetic Linkage
- Genetic Markers
- Genome
- Haplotypes
- Humans
- Male
- Mice
- Mice, Inbred CBA
- Mice, Mutant Strains/genetics
- Polymorphism, Genetic
- Repetitive Sequences, Nucleic Acid
- Sequence Analysis, DNA
- Tail/abnormalities
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Affiliation(s)
- J B Alfred
- Medical Research Council Human Genetics Unit, Western General Hospital, Edinburgh, UK.
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40
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Affiliation(s)
- L D Siracusa
- Kimmel Cancer Center, Jefferson Medical College, Department of Microbiology and Immunology, Philadelphia, Pennsylvania 19107-5541, USA
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41
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Abstract
The mouse Ulnaless locus is a semidominant mutation which displays defects in patterning along the proximal-distal and anterior-posterior axes of all four limbs. The first Ulnaless homozygotes have been generated, and they display a similar, though slightly more severe, limb phenotype than the heterozygotes. To create a refined genetic map of the Ulnaless region using molecular markers, four backcrosses segregating Ulnaless were established. A 0.4-cM interval containing the Ulnaless locus has been defined on mouse chromosome 2, which has identified Ulnaless as a possible allele of a Hoxd cluster gene(s). With this genetic map as a framework, a physical map of the Ulnaless region has been completed. Yeast artificial chromosomes covering this region have been isolated and ordered into a 2 Mb contig. Therefore, the region that must contain the Ulnaless locus has been defined and cloned, which will be invaluable for the identification of the molecular nature of the Ulnaless mutation.
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Affiliation(s)
- C L Peichel
- Department of Molecular Biology, Princeton University, New Jersey 08544, USA
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42
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Chambers DM, Abbott CM. Isolation and mapping of novel mouse brain cDNA clones containing trinucleotide repeats, and demonstration of novel alleles in recombinant inbred strains. Genome Res 1996; 6:715-23. [PMID: 8858346 DOI: 10.1101/gr.6.8.715] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Abnormal expansion of trinucleotide repeats (TRs) has now been implicated in the pathogenesis of at least nine human genetic disorders, particularly those in which anticipation and/or fragile sites have been demonstrated. Anticipation, the phenomenon of increasing severity of phenotype in successive generations, has never been seen in species other than man. Nevertheless, animal models for the dynamic mutation of TRs would be extremely valuable. We have screened a mouse brain cDNA library in an attempt to identify clones representing each of the 10 possible classes of trinucleotide repeat. Thirty-seven clones were analyzed in detail. Of the 37 sequences, 18 displayed significant levels of homology with sequences in GenBank, 10 of them with human expressed sequence tags (ESTs). We then analyzed 25 of the clones by PCR of the sequence containing the repeat in a number of different mouse strains and species to assess levels of variability of repeat length. Of the 25 clones analyzed in this way, 64% showed length variation between Mus musculus spp. and Mus spretus, and 32% showed variation between Mus musculus musculus-derived standard laboratory inbred strains. Where variation was detected (17 repeat-containing clones in all), the gene was mapped by linkage analysis. None of the repeats isolated showed any signs of extreme expansion. However, two of the repeats were shown to have undergone size changes during the establishment of a number of recombinant inbred strains, suggesting that these repeats are at least moderately unstable.
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Affiliation(s)
- D M Chambers
- Medical Research Council (MRC) Human Genetics Unit, Western General Hospital, Edinburgh, UK
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Williamson CM, Dutton ER, Abbott CM, Beechey CV, Ball ST, Peters J. Thirteen genes (Cebpb, E2f1, Tcf4, Cyp24, Pck1, Acra4, Edn3, Kcnb1, Mc3r, Ntsr, Cd40, Plcg1 and Rcad) that probably lie in the distal imprinting region of mouse chromosome 2 are not monoallelically expressed. Genet Res (Camb) 1995; 65:83-93. [PMID: 7781998 DOI: 10.1017/s0016672300033103] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Seven imprinted genes are currently known in the mouse but none have been identified yet in the distal imprinting region of mouse Chromosome (Chr) 2, a region which shows striking linkage conservation with human chromosome 20q13. Both maternal duplication/paternal deficiency and its reciprocal for distal Chr 2 lead to mice with abnormal body shapes and behavioural abnormalities. We have tested a number of candidate genes, that are either likely or known to lie within the distal imprinting region, for monoallelic expression. These included 3 genes (Cebpb, E2f1 and Tcf4) that express transcription factors, 2 genes (Cyp24 and Pck1) that are involved in growth, 5 genes (Acra4, Edn3, Kcnb1, Mc3r and Ntsr) where a defect could lead to neurological and probably behavioural problems, and 3 genes (Cd40, Plcg1 and Rcad) that are less obvious candidates but sequence information was available for designing primers to test their expression. On/off expression of each gene was tested by reverse transcription-polymerase chain reaction (RT-PCR) analysis of RNA extracted from tissues of mice with maternal duplication/paternal deficiency and its reciprocal for the distal region of Chr 2. None of the 13 genes is monoallelically expressed in the appropriate tissues before and shortly after birth which suggests that these genes are not imprinted later in development. This study has narrowed down the search for imprinted genes, and valuable information on which genes have been tested for on/off expression is provided. Since there is considerable evidence of conservation of imprinting between mouse and human, we would predict that the 13 genes are not imprinted in human. Five of the genes: E2f1, Tcf4, Kcnb1, Cd40 and Rcad, have not yet been mapped in human. However, because of the striking linkage conservation observed between mouse Chr 2 and human chromosome 20, we would expect these genes to map on human chromosome 20q13.
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Abbott CM, Lovegrove JU, Whitehouse DB, Hopkinson DA, Povey S. Prenatal diagnosis of alpha-1-antitrypsin deficiency by PCR of linked polymorphisms: a study of 17 cases. Prenat Diagn 1993; 13:544. [PMID: 8372083 DOI: 10.1002/pd.1970130620] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Abbott CM, Blank R, Eppig JT, Fiedorek FT, Frankel W, Friedman JM, Huppi KE, Jackson I, Steel K, Mock BA. Encyclopedia of the mouse genome III. October 1993. Mouse chromosome 4. Mamm Genome 1993; 4 Spec No:S58-71. [PMID: 8268685 DOI: 10.1007/bf00360830] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- C M Abbott
- Department of Genetics and Biochemistry, UCL, London, UK
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Pilz AJ, Abbott CM. Dinucleotide repeats in the mouse Hox-4.4 and Hox-4.5 genes on chromosome 2, and their analysis in the BXD and BXH recombinant inbred strains. Mamm Genome 1993; 4:129-30. [PMID: 8094302 DOI: 10.1007/bf00290440] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- A J Pilz
- Department of Genetics and Biometry, University College London, UK
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Abstract
Mutations in paired-box-containing (Pax) genes have recently been found to be the primary lesions underlying human genetic disorders such as Waardenburg's Syndrome type 1 and mouse developmental mutants such as undulated (un), splotch (Sp), and small eye (Sey). In addition, PAX-6 is a strong candidate gene for aniridia in man. Eight independent Pax genes have been isolated in the mouse. All eight map to distinct regions of the mouse genome; they do not appear to be clustered in the same way as some groups of homeobox-containing genes. We have now mapped the human homologs of all eight of these genes; PAX genes are found on human Chromosomes (Chr) 1, 2, 7, 9, 10, 11, and 20.
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Affiliation(s)
- A J Pilz
- Department of Genetics and Biometry, University College London, UK
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Affiliation(s)
- L D Siracusa
- Jefferson Cancer Institute, Department of Microbiology and Immunology, Philadelphia, Pennsylvania 19107-5541
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Pilz AJ, Willer E, Povey S, Abbott CM. The genes coding for phosphoenolpyruvate carboxykinase-1 (PCK1) and neuronal nicotinic acetylcholine receptor alpha 4 subunit (CHRNA4) map to human chromosome 20, extending the known region of homology with mouse chromosome 2. Ann Hum Genet 1992; 56:289-93. [PMID: 1492743 DOI: 10.1111/j.1469-1809.1992.tb01155.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The mouse genes for cytosolic phosphoenolpyruvate carboxykinase-1 (Pck-1) and neuronal nicotinic acetylcholine receptor alpha 4 subunit (Acra-4) both map to distal chromosome 2 (Siracusa et al. 1989; Bessis et al. 1990). We have utilized Southern blot analysis on human/rodent somatic cell hybrids to map the human homologues of both of these genes, PCK1 and CHRNA4, to human chromosome 20.
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Affiliation(s)
- A J Pilz
- Department of Genetics and Biometry, University College London, England
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Douglas AJ, Fox MF, Abbott CM, Hinks LJ, Sharpe G, Povey S, Thompson RJ. Structure and chromosomal localization of the human 2?,3?-cyclic nucleotide 3?-phosphodiesterase gene. Ann Hum Genet 1992; 56:243-54. [PMID: 1360194 DOI: 10.1111/j.1469-1809.1992.tb01149.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Human brain cDNA clones for the myelin associated enzyme 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) have been isolated and sequenced. The only 5' untranslated region (UTR) sequence found was that of a human CNPII mRNA, with no direct evidence for a CNPI mRNA. Human CNPase cDNAs were used to isolate genomic clones containing the human CNPase gene which is 9 kb long. Four exons were identified, separated by three introns, and the sequence of each exon and intron/exon boundary has been established. The polymerase chain reaction (PCR) was used to detect the presence of the human CNPase gene in DNA from a panel of rodent/human somatic cell hybrids. By this means the human CNPase gene was mapped to chromosome 17. In situ hybridization of a human CNPase genomic clone to metaphase chromosomes further localized this gene to chromosomal band 17q21.
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Affiliation(s)
- A J Douglas
- University Clinical Biochemistry, Southampton General Hospital, U.K
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