1
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Wiese C, Abele M, Al B, Altmann M, Steiner A, Kalbfuß N, Strohmayr A, Ravikumar R, Park CH, Brunschweiger B, Meng C, Facher E, Ehrhardt DW, Falter-Braun P, Wang ZY, Ludwig C, Assaad FF. Regulation of adaptive growth decisions via phosphorylation of the TRAPPII complex in Arabidopsis. J Cell Biol 2024; 223:e202311125. [PMID: 38558238 PMCID: PMC10983811 DOI: 10.1083/jcb.202311125] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 01/31/2024] [Accepted: 02/15/2024] [Indexed: 04/04/2024] Open
Abstract
Plants often adapt to adverse or stress conditions via differential growth. The trans-Golgi network (TGN) has been implicated in stress responses, but it is not clear in what capacity it mediates adaptive growth decisions. In this study, we assess the role of the TGN in stress responses by exploring the previously identified interactome of the Transport Protein Particle II (TRAPPII) complex required for TGN structure and function. We identified physical and genetic interactions between AtTRAPPII and shaggy-like kinases (GSK3/AtSKs) and provided in vitro and in vivo evidence that the TRAPPII phosphostatus mediates adaptive responses to abiotic cues. AtSKs are multifunctional kinases that integrate a broad range of signals. Similarly, the AtTRAPPII interactome is vast and considerably enriched in signaling components. An AtSK-TRAPPII interaction would integrate all levels of cellular organization and instruct the TGN, a central and highly discriminate cellular hub, as to how to mobilize and allocate resources to optimize growth and survival under limiting or adverse conditions.
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Affiliation(s)
- Christian Wiese
- Biotechnology of Natural Products, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
- Botany, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Miriam Abele
- Botany, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
- Bavarian Center for Biomolecular Mass Spectrometry (BayBioMS), TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Benjamin Al
- Botany, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Melina Altmann
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Alexander Steiner
- Botany, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Nils Kalbfuß
- Botany, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Alexander Strohmayr
- Biotechnology of Natural Products, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
- Botany, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Raksha Ravikumar
- Botany, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Chan Ho Park
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Barbara Brunschweiger
- Botany, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Chen Meng
- Bavarian Center for Biomolecular Mass Spectrometry (BayBioMS), TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Eva Facher
- Systematic Botany and Mycology, Faculty of Biology, Ludwig-Maximilians-Universität (LMU) München, Planegg-Martinsried, Germany
| | - David W. Ehrhardt
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Pascal Falter-Braun
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Zhi-Yong Wang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, USA
| | - Christina Ludwig
- Bavarian Center for Biomolecular Mass Spectrometry (BayBioMS), TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Farhah F. Assaad
- Biotechnology of Natural Products, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
- Botany, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
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2
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Wiese C, Abele M, Al B, Altmann M, Steiner A, Kalbfuß N, Strohmayr A, Ravikumar R, Park CH, Brunschweiger B, Meng C, Facher E, Ehrhardt DW, Falter-Braun P, Wang ZY, Ludwig C, Assaad FF. Regulation of adaptive growth decisions via phosphorylation of the TRAPPII complex in Arabidopsis. bioRxiv 2023:2023.04.24.537966. [PMID: 37986925 PMCID: PMC10659361 DOI: 10.1101/2023.04.24.537966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Plants often adapt to adverse or stress conditions via differential growth. The trans-Golgi Network (TGN) has been implicated in stress responses, but it is not clear in what capacity it mediates adaptive growth decisions. In this study, we assess the role of the TGN in stress responses by exploring the interactome of the Transport Protein Particle II (TRAPPII) complex, required for TGN structure and function. We identified physical and genetic interactions between TRAPPII and shaggy-like kinases (GSK3/AtSKs). Kinase assays and pharmacological inhibition provided in vitro and in vivo evidence that AtSKs target the TRAPPII-specific subunit AtTRS120/TRAPPC9. GSK3/AtSK phosphorylation sites in AtTRS120/TRAPPC9 were mutated, and the resulting AtTRS120 phosphovariants subjected to a variety of single and multiple stress conditions in planta . The non-phosphorylatable TRS120 mutant exhibited enhanced adaptation to multiple stress conditions and to osmotic stress whereas the phosphomimetic version was less resilient. Higher order inducible trappii atsk mutants had a synthetically enhanced defect in root gravitropism. Our results suggest that the TRAPPII phosphostatus mediates adaptive responses to abiotic cues. AtSKs are multifunctional kinases that integrate a broad range of signals. Similarly, the TRAPPII interactome is vast and considerably enriched in signaling components. An AtSK-TRAPPII interaction would integrate all levels of cellular organization and instruct the TGN, a central and highly discriminate cellular hub, as to how to mobilize and allocate resources to optimize growth and survival under limiting or adverse conditions.
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3
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Osborne R, Rehneke L, Lehmann S, Roberts J, Altmann M, Altmann S, Zhang Y, Köpff E, Dominguez-Ferreras A, Okechukwu E, Sergaki C, Rich-Griffin C, Ntoukakis V, Eichmann R, Shan W, Falter-Braun P, Schäfer P. Symbiont-host interactome mapping reveals effector-targeted modulation of hormone networks and activation of growth promotion. Nat Commun 2023; 14:4065. [PMID: 37429856 DOI: 10.1038/s41467-023-39885-5] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Accepted: 06/27/2023] [Indexed: 07/12/2023] Open
Abstract
Plants have benefited from interactions with symbionts for coping with challenging environments since the colonisation of land. The mechanisms of symbiont-mediated beneficial effects and similarities and differences to pathogen strategies are mostly unknown. Here, we use 106 (effector-) proteins, secreted by the symbiont Serendipita indica (Si) to modulate host physiology, to map interactions with Arabidopsis thaliana host proteins. Using integrative network analysis, we show significant convergence on target-proteins shared with pathogens and exclusive targeting of Arabidopsis proteins in the phytohormone signalling network. Functional in planta screening and phenotyping of Si effectors and interacting proteins reveals previously unknown hormone functions of Arabidopsis proteins and direct beneficial activities mediated by effectors in Arabidopsis. Thus, symbionts and pathogens target a shared molecular microbe-host interface. At the same time Si effectors specifically target the plant hormone network and constitute a powerful resource for elucidating the signalling network function and boosting plant productivity.
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Affiliation(s)
- Rory Osborne
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
- School of Biosciences, University of Birmingham, Edgbaston, B15 2TT, UK
| | - Laura Rehneke
- Institute of Phytopathology, Research Centre for BioSystems, Land Use and Nutrition, Justus Liebig University, 35392, Giessen, Germany
| | - Silke Lehmann
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
- Laboratory of Biotechnology and Marine Chemistry LBCM, EA3884, IUEM, Southern Brittany University, 56000, Vannes, France
| | - Jemma Roberts
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Melina Altmann
- Institute of Network Biology, Molecular Targets and Therapeutics Center, Helmholtz Munich, 85764, Munich-Neuherberg, Germany
| | - Stefan Altmann
- Institute of Network Biology, Molecular Targets and Therapeutics Center, Helmholtz Munich, 85764, Munich-Neuherberg, Germany
| | - Yingqi Zhang
- State Key Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy, Northwest A&F University, Yangling, 712100, China
| | - Eva Köpff
- Institute of Molecular Botany, Ulm University, 89069, Ulm, Germany
| | | | - Emeka Okechukwu
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Chrysi Sergaki
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | | | - Vardis Ntoukakis
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Ruth Eichmann
- Institute of Phytopathology, Research Centre for BioSystems, Land Use and Nutrition, Justus Liebig University, 35392, Giessen, Germany
| | - Weixing Shan
- State Key Laboratory of Crop Stress Biology in Arid Areas and College of Agronomy, Northwest A&F University, Yangling, 712100, China
| | - Pascal Falter-Braun
- Institute of Network Biology, Molecular Targets and Therapeutics Center, Helmholtz Munich, 85764, Munich-Neuherberg, Germany.
- Microbe-Host Interactions, Faculty of Biology, Ludwig-Maximilians-University München, 82152, Planegg-Martinsried, Germany.
| | - Patrick Schäfer
- Institute of Phytopathology, Research Centre for BioSystems, Land Use and Nutrition, Justus Liebig University, 35392, Giessen, Germany.
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4
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Kim DK, Weller B, Lin CW, Sheykhkarimli D, Knapp JJ, Dugied G, Zanzoni A, Pons C, Tofaute MJ, Maseko SB, Spirohn K, Laval F, Lambourne L, Kishore N, Rayhan A, Sauer M, Young V, Halder H, la Rosa NMD, Pogoutse O, Strobel A, Schwehn P, Li R, Rothballer ST, Altmann M, Cassonnet P, Coté AG, Vergara LE, Hazelwood I, Liu BB, Nguyen M, Pandiarajan R, Dohai B, Coloma PAR, Poirson J, Giuliana P, Willems L, Taipale M, Jacob Y, Hao T, Hill DE, Brun C, Twizere JC, Krappmann D, Heinig M, Falter C, Aloy P, Demeret C, Vidal M, Calderwood MA, Roth FP, Falter-Braun P. A proteome-scale map of the SARS-CoV-2-human contactome. Nat Biotechnol 2023; 41:140-149. [PMID: 36217029 PMCID: PMC9849141 DOI: 10.1038/s41587-022-01475-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 08/15/2022] [Indexed: 01/22/2023]
Abstract
Understanding the mechanisms of coronavirus disease 2019 (COVID-19) disease severity to efficiently design therapies for emerging virus variants remains an urgent challenge of the ongoing pandemic. Infection and immune reactions are mediated by direct contacts between viral molecules and the host proteome, and the vast majority of these virus-host contacts (the 'contactome') have not been identified. Here, we present a systematic contactome map of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with the human host encompassing more than 200 binary virus-host and intraviral protein-protein interactions. We find that host proteins genetically associated with comorbidities of severe illness and long COVID are enriched in SARS-CoV-2 targeted network communities. Evaluating contactome-derived hypotheses, we demonstrate that viral NSP14 activates nuclear factor κB (NF-κB)-dependent transcription, even in the presence of cytokine signaling. Moreover, for several tested host proteins, genetic knock-down substantially reduces viral replication. Additionally, we show for USP25 that this effect is phenocopied by the small-molecule inhibitor AZ1. Our results connect viral proteins to human genetic architecture for COVID-19 severity and offer potential therapeutic targets.
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Affiliation(s)
- Dae-Kyum Kim
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Cancer Genetics and Genomics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Benjamin Weller
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Chung-Wen Lin
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Dayag Sheykhkarimli
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Jennifer J Knapp
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Guillaume Dugied
- Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, Institut Pasteur, Paris, France
- UMR3569, Centre National de la Recherche Scientifique, Paris, France
- Université de Paris, Paris, France
| | | | - Carles Pons
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute for Science and Technology, Barcelona, Spain
| | - Marie J Tofaute
- Research Unit Cellular Signal Integration, Institute of Molecular Toxicology and Pharmacology, Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Sibusiso B Maseko
- Laboratory of Viral Interactomes, GIGA Institute, University of Liège, Liège, Belgium
| | - Kerstin Spirohn
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Florent Laval
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
- Laboratory of Viral Interactomes, GIGA Institute, University of Liège, Liège, Belgium
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA
- TERRA Teaching and Research Centre, University of Liège, Gembloux, Belgium
- Laboratory of Molecular and Cellular Epigenetics, GIGA Institute, University of Liège, Liège, Belgium
| | - Luke Lambourne
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Nishka Kishore
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Ashyad Rayhan
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Mayra Sauer
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Veronika Young
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Hridi Halder
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Nora Marín-de la Rosa
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Oxana Pogoutse
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Alexandra Strobel
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Patrick Schwehn
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Roujia Li
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Simin T Rothballer
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Melina Altmann
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Patricia Cassonnet
- Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, Institut Pasteur, Paris, France
- UMR3569, Centre National de la Recherche Scientifique, Paris, France
- Université de Paris, Paris, France
| | - Atina G Coté
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Lena Elorduy Vergara
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Isaiah Hazelwood
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Betty B Liu
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Maria Nguyen
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Ramakrishnan Pandiarajan
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Bushra Dohai
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Patricia A Rodriguez Coloma
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Juline Poirson
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Molecular Architecture of Life Program, Canadian Institute for Advanced Research (CIFAR), Toronto, ON, Canada
| | - Paolo Giuliana
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
| | - Luc Willems
- TERRA Teaching and Research Centre, University of Liège, Gembloux, Belgium
- Laboratory of Molecular and Cellular Epigenetics, GIGA Institute, University of Liège, Liège, Belgium
| | - Mikko Taipale
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Laboratory of Viral Interactomes, GIGA Institute, University of Liège, Liège, Belgium
| | - Yves Jacob
- Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, Institut Pasteur, Paris, France
- UMR3569, Centre National de la Recherche Scientifique, Paris, France
- Université de Paris, Paris, France
| | - Tong Hao
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - David E Hill
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Christine Brun
- Aix-Marseille Université, Inserm, TAGC, Marseille, France
- CNRS, Marseille, France
| | - Jean-Claude Twizere
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
- Laboratory of Viral Interactomes, GIGA Institute, University of Liège, Liège, Belgium
- TERRA Teaching and Research Centre, University of Liège, Gembloux, Belgium
| | - Daniel Krappmann
- Research Unit Cellular Signal Integration, Institute of Molecular Toxicology and Pharmacology, Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Matthias Heinig
- Institute of Computational Biology (ICB), Computational Health Center, Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
- Department of Informatics, Technische Universität München, Munich, Germany
| | - Claudia Falter
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Patrick Aloy
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute for Science and Technology, Barcelona, Spain
- Institució Catalana de Recerca I Estudis Avaçats (ICREA), Barcelona, Spain
| | - Caroline Demeret
- Unité de Génétique Moléculaire des Virus à ARN, Département de Virologie, Institut Pasteur, Paris, France.
- UMR3569, Centre National de la Recherche Scientifique, Paris, France.
- Université de Paris, Paris, France.
| | - Marc Vidal
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA.
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
| | - Michael A Calderwood
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA.
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA.
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA.
| | - Frederick P Roth
- Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, Toronto, Ontario, Canada.
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
- Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health System, Toronto, Ontario, Canada.
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA.
- Department of Computer Science, University of Toronto, Toronto, Ontario, Canada.
| | - Pascal Falter-Braun
- Institute of Network Biology (INET), Molecular Targets and Therapeutics Center (MTTC), Helmholtz Zentrum München, German Research Center for Environmental Health, Munich-Neuherberg, Germany.
- Microbe-Host Interactions, Faculty of Biology, Ludwig-Maximilians-Universität (LMU) München, Planegg-Martinsried, Germany.
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5
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Barth T, Altmann M, Batzlsperger C, Jägle H, Helbig H. [Is there a pathomechanical explanation for unilateral retinal haemorrhages in non-accidental head injury?]. Ophthalmologe 2021; 118:76. [PMID: 33275176 DOI: 10.1007/s00347-020-01277-1] [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: 10/22/2022]
Affiliation(s)
- T Barth
- Klinik und Poliklinik für Augenheilkunde, Universitätsklinikum Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Deutschland.
| | - M Altmann
- Klinik und Poliklinik für Augenheilkunde, Universitätsklinikum Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Deutschland
| | - C Batzlsperger
- Klinik für Kinder- und Jugendmedizin, Neonatologie, Neuropädiatrie, DONAUISAR Klinikum Deggendorf, Deggendorf, Deutschland
| | - H Jägle
- Klinik und Poliklinik für Augenheilkunde, Universitätsklinikum Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Deutschland
| | - H Helbig
- Klinik und Poliklinik für Augenheilkunde, Universitätsklinikum Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Deutschland
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6
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Gruner K, Leissing F, Sinitski D, Thieron H, Axstmann C, Baumgarten K, Reinstädler A, Winkler P, Altmann M, Flatley A, Jaouannet M, Zienkiewicz K, Feussner I, Keller H, Coustau C, Falter-Braun P, Feederle R, Bernhagen J, Panstruga R. Chemokine-like MDL proteins modulate flowering time and innate immunity in plants. J Biol Chem 2021; 296:100611. [PMID: 33798552 PMCID: PMC8122116 DOI: 10.1016/j.jbc.2021.100611] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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: 01/22/2021] [Revised: 03/18/2021] [Accepted: 03/29/2021] [Indexed: 12/19/2022] Open
Abstract
Human macrophage migration inhibitory factor (MIF) is an atypical chemokine implicated in intercellular signaling and innate immunity. MIF orthologs (MIF/D-DT-like proteins, MDLs) are present throughout the plant kingdom, but remain experimentally unexplored in these organisms. Here, we provide an in planta characterization and functional analysis of the three-member gene/protein MDL family in Arabidopsis thaliana. Subcellular localization experiments indicated a nucleo-cytoplasmic distribution of MDL1 and MDL2, while MDL3 is localized to peroxisomes. Protein–protein interaction assays revealed the in vivo formation of MDL1, MDL2, and MDL3 homo-oligomers, as well as the formation of MDL1-MDL2 hetero-oligomers. Functionally, Arabidopsismdl mutants exhibited a delayed transition from vegetative to reproductive growth (flowering) under long-day conditions, but not in a short-day environment. In addition, mdl mutants were more resistant to colonization by the bacterial pathogen Pseudomonas syringae pv. maculicola. The latter phenotype was compromised by the additional mutation of SALICYLIC ACID INDUCTION DEFICIENT 2 (SID2), a gene implicated in the defense-induced biosynthesis of the key signaling molecule salicylic acid. However, the enhanced antibacterial immunity was not associated with any constitutive or pathogen-induced alterations in the levels of characteristic phytohormones or defense-associated metabolites. Interestingly, bacterial infection triggered relocalization and accumulation of MDL1 and MDL2 at the peripheral lobes of leaf epidermal cells. Collectively, our data indicate redundant functionality and a complex interplay between the three chemokine-like Arabidopsis MDL proteins in the regulation of both developmental and immune-related processes. These insights expand the comparative cross-kingdom analysis of MIF/MDL signaling in human and plant systems.
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Affiliation(s)
- Katrin Gruner
- RWTH Aachen University, Institute for Biology I, Unit of Plant Molecular Cell Biology, Aachen, Germany
| | - Franz Leissing
- RWTH Aachen University, Institute for Biology I, Unit of Plant Molecular Cell Biology, Aachen, Germany
| | - Dzmitry Sinitski
- Ludwig-Maximilians-University (LMU), LMU University Hospital, Chair of Vascular Biology, Institute for Stroke and Dementia Research (ISD), Munich, Germany
| | - Hannah Thieron
- RWTH Aachen University, Institute for Biology I, Unit of Plant Molecular Cell Biology, Aachen, Germany
| | - Christian Axstmann
- RWTH Aachen University, Institute for Biology I, Unit of Plant Molecular Cell Biology, Aachen, Germany
| | - Kira Baumgarten
- RWTH Aachen University, Institute for Biology I, Unit of Plant Molecular Cell Biology, Aachen, Germany
| | - Anja Reinstädler
- RWTH Aachen University, Institute for Biology I, Unit of Plant Molecular Cell Biology, Aachen, Germany
| | - Pascal Winkler
- RWTH Aachen University, Institute for Biology I, Unit of Plant Molecular Cell Biology, Aachen, Germany
| | - Melina Altmann
- Helmholtz Center Munich, German Research Center for Environmental Health, Institute of Network Biology (INET), Munich-Neuherberg, Germany
| | - Andrew Flatley
- Helmholtz Center Munich, German Research Center for Environmental Health, Institute for Diabetes and Obesity, Monoclonal Antibody Core Facility, Munich-Neuherberg, Germany
| | - Maëlle Jaouannet
- Institut Sophia Agrobiotech, Université Côte d'Azur, INRAE, CNRS, Sophia Antipolis, France
| | - Krzysztof Zienkiewicz
- University of Goettingen, Albrecht von Haller Institute and Goettingen Center for Molecular Biosciences (GZMB), Department of Plant Biochemistry, Goettingen, Germany; University of Goettingen, Goettingen Center for Molecular Biosciences (GZMB), Service Unit for Metabolomics and Lipidomics, Goettingen, Germany
| | - Ivo Feussner
- University of Goettingen, Albrecht von Haller Institute and Goettingen Center for Molecular Biosciences (GZMB), Department of Plant Biochemistry, Goettingen, Germany; University of Goettingen, Goettingen Center for Molecular Biosciences (GZMB), Service Unit for Metabolomics and Lipidomics, Goettingen, Germany
| | - Harald Keller
- Institut Sophia Agrobiotech, Université Côte d'Azur, INRAE, CNRS, Sophia Antipolis, France
| | - Christine Coustau
- Institut Sophia Agrobiotech, Université Côte d'Azur, INRAE, CNRS, Sophia Antipolis, France
| | - Pascal Falter-Braun
- Helmholtz Center Munich, German Research Center for Environmental Health, Institute of Network Biology (INET), Munich-Neuherberg, Germany; Ludwig-Maximilians-Universität (LMU), Faculty of Biology, Chair of Microbe-Host Interactions, Planegg-Martinsried, Germany
| | - Regina Feederle
- Helmholtz Center Munich, German Research Center for Environmental Health, Institute for Diabetes and Obesity, Monoclonal Antibody Core Facility, Munich-Neuherberg, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Jürgen Bernhagen
- Ludwig-Maximilians-University (LMU), LMU University Hospital, Chair of Vascular Biology, Institute for Stroke and Dementia Research (ISD), Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
| | - Ralph Panstruga
- RWTH Aachen University, Institute for Biology I, Unit of Plant Molecular Cell Biology, Aachen, Germany.
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7
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Abstract
Ein 2,5 Monate alter Junge und ein 2 Monate altes Mädchen wurden wegen schwerer Bewusstseinstrübung pädiatrisch behandelt. Bei beiden Kindern fanden sich Subduralhämatome. Bei Verdacht auf nichtakzidentelles Schädel-Hirn-Trauma (NAHI) erfolgte eine Untersuchung des Augenhintergrundes, bei der sich bei beiden Säuglingen unilaterale Netzhautblutungen zeigten. Nach intensiver Differenzialdiagnostik wurde in beiden Fällen der Verdacht auf ein NAHI gestellt und eine rechtsmedizinische Begutachtung initiiert. Wichtig an dieser Fallserie ist, dass die Einseitigkeit von Netzhautblutungen ein NAHI nicht ausschließt.
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Affiliation(s)
- T Barth
- Klinik und Poliklinik für Augenheilkunde, Universitätsklinikum Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Deutschland.
| | - M Altmann
- Klinik und Poliklinik für Augenheilkunde, Universitätsklinikum Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Deutschland
| | - C Batzlsperger
- Klinik für Kinder- und Jugendmedizin, Neonatologie, Neuropädiatrie, DONAUISAR Klinikum Deggendorf, Perlasbergerstr. 41, 94469, Deggendorf, Deutschland
| | - H Jägle
- Klinik und Poliklinik für Augenheilkunde, Universitätsklinikum Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Deutschland
| | - H Helbig
- Klinik und Poliklinik für Augenheilkunde, Universitätsklinikum Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Deutschland
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8
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Altmann M, Altmann S, Rodriguez PA, Weller B, Vergara LE, Palme J, la Rosa NMD, Sauer M, Wenig M, Villaécija-Aguilar JA, Sales J, Lin CW, Pandiarajan R, Young V, Strobel A, Gross L, Carbonnel S, Kugler KG, Garcia-Molina A, Bassel GW, Falter C, Mayer KFX, Gutjahr C, Vlot AC, Grill E, Falter-Braun P. Publisher Correction: Extensive signal integration by the phytohormone protein network. Nature 2020; 584:E34. [PMID: 32724209 DOI: 10.1038/s41586-020-2585-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Affiliation(s)
- Melina Altmann
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Stefan Altmann
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Patricia A Rodriguez
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Benjamin Weller
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Lena Elorduy Vergara
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Julius Palme
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany.,Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Nora Marín-de la Rosa
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Mayra Sauer
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Marion Wenig
- Inducible Resistance Signaling Group, Institute of Biochemical Plant Pathology (BIOP), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | | | - Jennifer Sales
- Inducible Resistance Signaling Group, Institute of Biochemical Plant Pathology (BIOP), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Chung-Wen Lin
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Ramakrishnan Pandiarajan
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Veronika Young
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Alexandra Strobel
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Lisa Gross
- Botany, TUM School of Life Sciences, Technical University of Munich (TUM), Freising, Germany
| | - Samy Carbonnel
- Genetics, Faculty of Biology, Ludwig-Maximilians-Universität (LMU) München, Planegg-Martinsried, Germany
| | - Karl G Kugler
- Plant Genome and Systems Biology (PGSB), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Antoni Garcia-Molina
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany.,Plant Molecular Biology, Faculty of Biology, Ludwig-Maximilians-Universität (LMU) München, Planegg-Martinsried, Germany
| | - George W Bassel
- School of Biosciences, University of Birmingham, Birmingham, UK
| | - Claudia Falter
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Klaus F X Mayer
- Plant Genome and Systems Biology (PGSB), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany.,TUM School of Life Sciences, Technical University of Munich (TUM), Freising, Germany
| | - Caroline Gutjahr
- Plant Genetics, TUM School of Life Sciences, Technical University of Munich (TUM), Freising, Germany.,Genetics, Faculty of Biology, Ludwig-Maximilians-Universität (LMU) München, Planegg-Martinsried, Germany
| | - A Corina Vlot
- Inducible Resistance Signaling Group, Institute of Biochemical Plant Pathology (BIOP), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany
| | - Erwin Grill
- Botany, TUM School of Life Sciences, Technical University of Munich (TUM), Freising, Germany
| | - Pascal Falter-Braun
- Institute of Network Biology (INET), Helmholtz Center Munich, German Research Center for Environmental Health, Munich-Neuherberg, Germany. .,Microbe-Host Interactions, Faculty of Biology, Ludwig-Maximilians-Universität (LMU) München, Planegg-Martinsried, Germany.
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9
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Garcia VJ, Xu SL, Ravikumar R, Wang W, Elliott L, Gonzalez E, Fesenko M, Altmann M, Brunschweiger B, Falter-Braun P, Moore I, Burlingame A, Assaad FF, Wang ZY. TRIPP Is a Plant-Specific Component of the Arabidopsis TRAPPII Membrane Trafficking Complex with Important Roles in Plant Development. Plant Cell 2020; 32:2424-2443. [PMID: 32371545 PMCID: PMC7346556 DOI: 10.1105/tpc.20.00044] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/25/2020] [Accepted: 04/23/2020] [Indexed: 05/23/2023]
Abstract
How the membrane trafficking system spatially organizes intracellular activities and intercellular signaling networks in plants is not well understood. Transport Protein Particle (TRAPP) complexes play key roles in the selective delivery of membrane vesicles to various subcellular compartments in yeast and animals but remain to be fully characterized in plants. Here, we investigated TRAPP complexes in Arabidopsis (Arabidopsis thaliana) using immunoprecipitation followed by quantitative mass spectrometry analysis of AtTRS33, a conserved core component of all TRAPP complexes. We identified 14 AtTRS33-interacting proteins, including homologs of all 13 TRAPP components in mammals and a protein that has homologs only in multicellular photosynthetic organisms and is thus named TRAPP-Interacting Plant Protein (TRIPP). TRIPP specifically associates with the TRAPPII complex through binary interactions with two TRAPPII-specific subunits. TRIPP colocalized with a subset of TRS33 compartments and trans-Golgi network markers in a TRS33-dependent manner. Loss-of-function tripp mutants exhibited dwarfism, sterility, partial photomorphogenesis in the dark, reduced polarity of the auxin transporter PIN2, incomplete cross wall formation, and altered localization of a TRAPPII-specific component. Therefore, TRIPP is a plant-specific component of the TRAPPII complex with important functions in trafficking, plant growth, and development.
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Affiliation(s)
- Veder J Garcia
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Shou-Ling Xu
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Raksha Ravikumar
- Plant Science Department, Botany, Technische Universität München, 85354 Freising, Germany
| | - Wenfei Wang
- Basic Forestry and Proteomics Research Center, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Liam Elliott
- Department of Plant Sciences, University of Oxford, Oxford, OX1 3RB, United Kingdom
| | - Efren Gonzalez
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
| | - Mary Fesenko
- Department of Plant Sciences, University of Oxford, Oxford, OX1 3RB, United Kingdom
| | - Melina Altmann
- Institute of Network Biology, Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt, 85764 Neuherberg, Germany
| | - Barbara Brunschweiger
- Plant Science Department, Botany, Technische Universität München, 85354 Freising, Germany
| | - Pascal Falter-Braun
- Institute of Network Biology, Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt, 85764 Neuherberg, Germany
- Faculty of Biology, Microbe-Host-Interactions, Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Ian Moore
- Department of Plant Sciences, University of Oxford, Oxford, OX1 3RB, United Kingdom
| | - Alma Burlingame
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California 94158
| | - Farhah F Assaad
- Plant Science Department, Botany, Technische Universität München, 85354 Freising, Germany
| | - Zhi-Yong Wang
- Department of Plant Biology, Carnegie Institution for Science, Stanford, California 94305
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10
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Kalde M, Elliott L, Ravikumar R, Rybak K, Altmann M, Klaeger S, Wiese C, Abele M, Al B, Kalbfuß N, Qi X, Steiner A, Meng C, Zheng H, Kuster B, Falter-Braun P, Ludwig C, Moore I, Assaad FF. Interactions between Transport Protein Particle (TRAPP) complexes and Rab GTPases in Arabidopsis. Plant J 2019; 100:279-297. [PMID: 31264742 DOI: 10.1111/tpj.14442] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 05/15/2019] [Accepted: 06/11/2019] [Indexed: 05/23/2023]
Abstract
Transport Protein Particle II (TRAPPII) is essential for exocytosis, endocytosis, protein sorting and cytokinesis. In spite of a considerable understanding of its biological role, little information is known about Arabidopsis TRAPPII complex topology and molecular function. In this study, independent proteomic approaches initiated with TRAPP components or Rab-A GTPase variants converge on the TRAPPII complex. We show that the Arabidopsis genome encodes the full complement of 13 TRAPPC subunits, including four previously unidentified components. A dimerization model is proposed to account for binary interactions between TRAPPII subunits. Preferential binding to dominant negative (GDP-bound) versus wild-type or constitutively active (GTP-bound) RAB-A2a variants discriminates between TRAPPII and TRAPPIII subunits and shows that Arabidopsis complexes differ from yeast but resemble metazoan TRAPP complexes. Analyzes of Rab-A mutant variants in trappii backgrounds provide genetic evidence that TRAPPII functions upstream of RAB-A2a, allowing us to propose that TRAPPII is likely to behave as a guanine nucleotide exchange factor (GEF) for the RAB-A2a GTPase. GEFs catalyze exchange of GDP for GTP; the GTP-bound, activated, Rab then recruits a diverse local network of Rab effectors to specify membrane identity in subsequent vesicle fusion events. Understanding GEF-Rab interactions will be crucial to unravel the co-ordination of plant membrane traffic.
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Affiliation(s)
- Monika Kalde
- Department of Plant Sciences, University of Oxford, Oxford, OX1 3RB, UK
| | - Liam Elliott
- Department of Plant Sciences, University of Oxford, Oxford, OX1 3RB, UK
| | - Raksha Ravikumar
- Plant Science Department, Botany, Technische Universität München, Freising, 85354, Germany
| | - Katarzyna Rybak
- Plant Science Department, Botany, Technische Universität München, Freising, 85354, Germany
| | - Melina Altmann
- Institute of Network Biology (INET), Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Neuherberg, 85764, Germany
| | - Susan Klaeger
- Chair of Proteomics and Bioanalytics, Technische Universität München, Freising, 85354, Germany
| | - Christian Wiese
- Plant Science Department, Botany, Technische Universität München, Freising, 85354, Germany
| | - Miriam Abele
- Plant Science Department, Botany, Technische Universität München, Freising, 85354, Germany
| | - Benjamin Al
- Plant Science Department, Botany, Technische Universität München, Freising, 85354, Germany
| | - Nils Kalbfuß
- Plant Science Department, Botany, Technische Universität München, Freising, 85354, Germany
| | - Xingyun Qi
- Department of Biology, McGill University, Montreal, H3B 1A1, Canada
| | - Alexander Steiner
- Plant Science Department, Botany, Technische Universität München, Freising, 85354, Germany
| | - Chen Meng
- BayBioMS, Bavarian Center for Biomolecular Mass Spectrometry, Technische Universität München, Freising, 85354, Germany
| | - Huanquan Zheng
- Department of Biology, McGill University, Montreal, H3B 1A1, Canada
| | - Bernhard Kuster
- Chair of Proteomics and Bioanalytics, Technische Universität München, Freising, 85354, Germany
| | - Pascal Falter-Braun
- Institute of Network Biology (INET), Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Neuherberg, 85764, Germany
- Faculty of Biology, Microbe-Host-Interactions, Ludwig-Maximilians-Universität (LMU) München, Planegg-Martinsried, 82152, Germany
| | - Christina Ludwig
- BayBioMS, Bavarian Center for Biomolecular Mass Spectrometry, Technische Universität München, Freising, 85354, Germany
| | - Ian Moore
- Department of Plant Sciences, University of Oxford, Oxford, OX1 3RB, UK
| | - Farhah F Assaad
- Plant Science Department, Botany, Technische Universität München, Freising, 85354, Germany
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11
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Ravikumar R, Kalbfuß N, Gendre D, Steiner A, Altmann M, Altmann S, Rybak K, Edelmann H, Stephan F, Lampe M, Facher E, Wanner G, Falter-Braun P, Bhalerao RP, Assaad FF. Independent yet overlapping pathways ensure the robustness and responsiveness of trans-Golgi network functions in Arabidopsis. Development 2018; 145:145/21/dev169201. [DOI: 10.1242/dev.169201] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 10/02/2018] [Indexed: 01/21/2023]
Abstract
ABSTRACT
The trans-Golgi-network (TGN) has essential housekeeping functions in secretion, endocytosis and protein sorting, but also more specialized functions in plant development. How the robustness of basal TGN function is ensured while specialized functions are differentially regulated is poorly understood. Here, we investigate two key regulators of TGN structure and function, ECHIDNA and the Transport Protein Particle II (TRAPPII) tethering complex. An analysis of physical, network and genetic interactions suggests that two network communities are implicated in TGN function and that ECHIDNA and TRAPPII belong to distinct yet overlapping pathways. Whereas ECHIDNA and TRAPPII colocalized at the TGN in interphase cells, their localization diverged in dividing cells. Moreover, ECHIDNA and TRAPPII localization patterns were mutually independent. TGN structure, endocytosis and sorting decisions were differentially impacted in echidna and trappii mutants. Our analyses point to a partitioning of specialized TGN functions, with ECHIDNA being required for cell elongation and TRAPPII for cytokinesis. Two independent pathways able to compensate for each other might contribute to the robustness of TGN housekeeping functions and to the responsiveness and fine tuning of its specialized functions.
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Affiliation(s)
- Raksha Ravikumar
- Plant Science Department, Botany, Technische Universität München, 85354 Freising, Germany
| | - Nils Kalbfuß
- Plant Science Department, Botany, Technische Universität München, 85354 Freising, Germany
| | - Delphine Gendre
- Umeå Plant Science Centre, Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S-901 83 Umeå, Sweden
| | - Alexander Steiner
- Plant Science Department, Botany, Technische Universität München, 85354 Freising, Germany
| | - Melina Altmann
- Institute of Network Biology (INET), Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), 85764 Neuherberg, Germany
| | - Stefan Altmann
- Institute of Network Biology (INET), Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), 85764 Neuherberg, Germany
| | - Katarzyna Rybak
- Plant Science Department, Botany, Technische Universität München, 85354 Freising, Germany
| | - Holger Edelmann
- Plant Science Department, Botany, Technische Universität München, 85354 Freising, Germany
| | - Friederike Stephan
- Plant Science Department, Botany, Technische Universität München, 85354 Freising, Germany
| | - Marko Lampe
- Advanced Light Microscopy Facility, EMBL Heidelberg, 69117 Heidelberg, Germany
| | - Eva Facher
- Systematic Botany and Mycology, Faculty of Biology, Dept. I Ludwig-Maximilians-Universität, 80638 Munich, Germany
| | - Gerhard Wanner
- Faculty of Biology, Dept. I, Ludwig-Maximillians Universität, 82152 Planegg-Martinsried, Germany
| | - Pascal Falter-Braun
- Institute of Network Biology (INET), Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), 85764 Neuherberg, Germany
- Faculty of Biology, Microbe-Host-Interactions, Ludwig-Maximilians-Universität (LMU) München, 82152 Planegg-Martinsried, Germany
| | - Rishikesh P. Bhalerao
- Umeå Plant Science Centre, Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, S-901 83 Umeå, Sweden
| | - Farhah F. Assaad
- Plant Science Department, Botany, Technische Universität München, 85354 Freising, Germany
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12
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Abstract
In this article, we describe a Y2H interaction mapping protocol for systematically screening medium-to-large collections of open reading frames (ORFs) against each other. The protocol is well suited for analysis of focused networks, for modules of interest, assembling genome-scale interactome maps, and investigating host-microbe interactions. The four-step high-throughput protocol has a demonstrated low false-discovery rate that is essential for producing meaningful network maps. Following the assembly of yeast expression clones from an existing ORFeome collection, we describe in detail the four-step procedure that begins with the primary screen using minipools, followed by secondary verification of primary positives, identification of candidate interaction pairs by sequencing, and a final verification step using fresh inoculants. In addition to this core protocol, aspects of network mapping and quality control will be discussed briefly. © 2018 by John Wiley & Sons, Inc.
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Affiliation(s)
- Melina Altmann
- Helmholtz Zentrum München, Institute of Network Biology (INET), Munich, Germany
| | - Stefan Altmann
- Helmholtz Zentrum München, Institute of Network Biology (INET), Munich, Germany
| | - Claudia Falter
- Helmholtz Zentrum München, Institute of Network Biology (INET), Munich, Germany
| | - Pascal Falter-Braun
- Helmholtz Zentrum München, Institute of Network Biology (INET), Munich, Germany.,Ludwig-Maximilians-Universität München, Microbe-Host Interactions, Munich, Germany
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13
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Rincón M, Díaz-López E, Selnes P, Vegge K, Altmann M, Fladby T, Bjørnerud A. Improved Automatic Segmentation of White Matter Hyperintensities in MRI Based on Multilevel Lesion Features. Neuroinformatics 2018; 15:231-245. [PMID: 28378263 DOI: 10.1007/s12021-017-9328-y] [Citation(s) in RCA: 12] [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] [Indexed: 11/25/2022]
Abstract
Brain white matter hyperintensities (WMHs) are linked to increased risk of cerebrovascular and neurodegenerative diseases among the elderly. Consequently, detection and characterization of WMHs are of significant clinical importance. We propose a novel approach for WMH segmentation from multi-contrast MRI where both voxel-based and lesion-based information are used to improve overall performance in both volume-oriented and object-oriented metrics. Our segmentation method (AMOS-2D) consists of four stages following a "generate-and-test" approach: pre-processing, Gaussian white matter (WM) modelling, hierarchical multi-threshold WMH segmentation and object-based WMH filtering using support vector machines. Data from 28 subjects was used in this study covering a wide range of lesion loads. Volumetric T1-weighted images and 2D fluid attenuated inversion recovery (FLAIR) images were used as basis for the WM model and lesion masks defined manually in each subject by experts were used for training and evaluating the proposed method. The method obtained an average agreement (in terms of the Dice similarity coefficient, DSC) with experts equivalent to inter-expert agreement both in terms of WMH number (DSC = 0.637 vs. 0.651) and volume (DSC = 0.743 vs. 0.781). It allowed higher accuracy in detecting WMH compared to alternative methods tested and was further found to be insensitive to WMH lesion burden. Good agreement with expert annotations combined with stable performance largely independent of lesion burden suggests that AMOS-2D will be a valuable tool for fully automated WMH segmentation in patients with cerebrovascular and neurodegenerative pathologies.
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Affiliation(s)
- M Rincón
- Department of Artificial Intelligence, UNED, Madrid, Spain.
| | - E Díaz-López
- Department of Artificial Intelligence, UNED, Madrid, Spain
| | - P Selnes
- Department of Neurology, Akershus University Hospital, Oslo, Norway
| | - K Vegge
- Department of Radiology, Akershus University Hospital, Oslo, Norway
| | - M Altmann
- Department of Neurology, Akershus University Hospital, Oslo, Norway
| | - T Fladby
- Department of Neurology, Akershus University Hospital, Oslo, Norway
| | - A Bjørnerud
- The Intervention Centre, Oslo University Hospital, Oslo, Norway
- Department of Physics, University of Oslo, Oslo, Norway
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Garcia-Molina A, Altmann M, Alkofer A, Epple PM, Dangl JL, Falter-Braun P. LSU network hubs integrate abiotic and biotic stress responses via interaction with the superoxide dismutase FSD2. J Exp Bot 2017; 68:1185-1197. [PMID: 28207043 PMCID: PMC5441861 DOI: 10.1093/jxb/erw498] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In natural environments, plants often experience different stresses simultaneously, and adverse abiotic conditions can weaken the plant immune system. Interactome mapping revealed that the LOW SULPHUR UPREGULATED (LSU) proteins are hubs in an Arabidopsis protein interaction network that are targeted by virulence effectors from evolutionarily diverse pathogens. Here we show that LSU proteins are up-regulated in several abiotic and biotic stress conditions, such as nutrient depletion or salt stress, by both transcriptional and post-translational mechanisms. Interference with LSU expression prevents chloroplastic reactive oxygen species (ROS) production and proper stomatal closure during sulphur stress. We demonstrate that LSU1 interacts with the chloroplastic superoxide dismutase FSD2 and stimulates its enzymatic activity in vivo and in vitro. Pseudomonas syringae virulence effectors interfere with this interaction and preclude re-localization of LSU1 to chloroplasts. We demonstrate that reduced LSU levels cause a moderately enhanced disease susceptibility in plants exposed to abiotic stresses such as nutrient deficiency, high salinity, or heavy metal toxicity, whereas LSU1 overexpression confers significant disease resistance in several of these conditions. Our data suggest that the network hub LSU1 plays an important role in co-ordinating plant immune responses across a spectrum of abiotic stress conditions.
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Affiliation(s)
- Antoni Garcia-Molina
- Technische Universität München (TUM), School for Life Sciences Weihenstephan (WZW), Plant Systems Biology, Emil-Ramann-Straße, 4, D-85354 Freising, Germany
| | - Melina Altmann
- Technische Universität München (TUM), School for Life Sciences Weihenstephan (WZW), Plant Systems Biology, Emil-Ramann-Straße, 4, D-85354 Freising, Germany
| | - Angela Alkofer
- Technische Universität München (TUM), School for Life Sciences Weihenstephan (WZW), Plant Systems Biology, Emil-Ramann-Straße, 4, D-85354 Freising, Germany
| | - Petra M Epple
- Howard Hughes Medical Institute and Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Jeffery L Dangl
- BASF Plant Science LP, Research Triangle Park, NC 27709, USA
| | - Pascal Falter-Braun
- Institute of Network Biology (INET), Helmholtz Zentrum München (HMGU), German Research Center for Environmental Health, 85764 Neuherberg, Germany
- Department of Microbe-Host Interactions, Ludwig-Maximilians-Universität München (LMU Munich), Planegg-Martinsried, Germany
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15
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Steiner A, Rybak K, Altmann M, McFarlane HE, Klaeger S, Nguyen N, Facher E, Ivakov A, Wanner G, Kuster B, Persson S, Braun P, Hauser MT, Assaad FF. Cell cycle-regulated PLEIADE/AtMAP65-3 links membrane and microtubule dynamics during plant cytokinesis. Plant J 2016; 88:531-541. [PMID: 27420177 DOI: 10.1111/tpj.13275] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 06/27/2016] [Indexed: 06/06/2023]
Abstract
Cytokinesis, the partitioning of the cytoplasm following nuclear division, requires extensive coordination between cell cycle cues, membrane trafficking and microtubule dynamics. Plant cytokinesis occurs within a transient membrane compartment known as the cell plate, to which vesicles are delivered by a plant-specific microtubule array, the phragmoplast. While membrane proteins required for cytokinesis are known, how these are coordinated with microtubule dynamics and regulated by cell cycle cues remains unclear. Here, we document physical and genetic interactions between Transport Protein Particle II (TRAPPII) tethering factors and microtubule-associated proteins of the PLEIADE/AtMAP65 family. These interactions do not specifically affect the recruitment of either TRAPPII or MAP65 proteins to the cell plate or midzone. Rather, and based on single versus double mutant phenotypes, it appears that they are required to coordinate cytokinesis with the nuclear division cycle. As MAP65 family members are known to be targets of cell cycle-regulated kinases, our results provide a conceptual framework for how membrane and microtubule dynamics may be coordinated with each other and with the nuclear cycle during plant cytokinesis.
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Affiliation(s)
| | - Katarzyna Rybak
- Botany, Technische Universität München, Freising, 85354, Germany
| | - Melina Altmann
- Plant Systems Biology, Technische Universität München, Freising, 85354, Germany
| | - Heather E McFarlane
- School of Biosciences, University of Melbourne, Parkville, 3010, Victoria, Australia
- Max Planck Institute for Molecular Plant Physiology, Postdam, 14476, Germany
| | - Susan Klaeger
- Chair of Proteomics and Bioanalytics, Technische Universität München, Freising, 85354, Germany
| | - Ngoc Nguyen
- Botany, Technische Universität München, Freising, 85354, Germany
| | - Eva Facher
- Department Biologie I, Ludwig-Maximillians Universität, Planegg-Martinsried, 82152, Germany
| | - Alexander Ivakov
- School of Biosciences, University of Melbourne, Parkville, 3010, Victoria, Australia
- Max Planck Institute for Molecular Plant Physiology, Postdam, 14476, Germany
| | - Gerhard Wanner
- Department Biologie I, Ludwig-Maximillians Universität, Planegg-Martinsried, 82152, Germany
| | - Bernhard Kuster
- Chair of Proteomics and Bioanalytics, Technische Universität München, Freising, 85354, Germany
| | - Staffan Persson
- School of Biosciences, University of Melbourne, Parkville, 3010, Victoria, Australia
- Max Planck Institute for Molecular Plant Physiology, Postdam, 14476, Germany
- School of Biosciences, ARC Centre of Excellence in Plant Cell Walls, University of Melbourne, Parkville, 3010, Victoria, Australia
| | - Pascal Braun
- Plant Systems Biology, Technische Universität München, Freising, 85354, Germany
| | - Marie-Theres Hauser
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, 1190, Austria
| | - Farhah F Assaad
- Botany, Technische Universität München, Freising, 85354, Germany
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Ertl M, Barinka F, Torka E, Altmann M, Pfister K, Helbig H, Bogdahn U, Gamulescu MA, Schlachetzki F. Ocular color-coded sonography - a promising tool for neurologists and intensive care physicians. Ultraschall Med 2014; 35:422-431. [PMID: 24647767 DOI: 10.1055/s-0034-1366113] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Ocular color-coded duplex sonography (OCCS), when performed within the safety limits of diagnostic ultrasonography, is an easy noninvasive technique with high potential for diagnosis and therapy in diseases with raised intracranial pressure and vascular diseases affecting the eye. Despite the capabilities of modern ultrasound systems and its scientific validation, OCCS has not gained widespread use in neurological practice. In this review, the authors describe the technique and main parameter settings of OCCS systems to reduce potential risks as thermal or cavitational effects for sensitive orbital structures. Applications of OCCS are the determination of intracranial pressure in emergency medicine, and follow-up evaluations of idiopathic intracranial hypertension and ventricular shunting by measuring the optic nerve sheath diameter. A diameter of 5.7 - 6.0 mm corresponds well with symptomatically increased intracranial pressure (> 20 cmH2O). OCCS also helps to discriminate between different etiologies of central retinal artery occlusion - by visualization of a "spot sign" and Doppler flow analysis of the central retinal artery - and aids the differential diagnosis of papilledema. At the end perspectives are illustrated that combine established ultrasound methods such as transcranial color-coded sonography with OCCS.
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Affiliation(s)
- M Ertl
- Department of Neurology, Bezirksklinikum Regensburg, University of Regensburg
| | - F Barinka
- Department of Neurology, Bezirksklinikum Regensburg, University of Regensburg
| | - E Torka
- Department of Neurology, Bezirksklinikum Regensburg, University of Regensburg
| | - M Altmann
- Department of Opthalmology, University of Regensburg
| | - K Pfister
- Department of Surgery, Vascular Surgery and Endovascular Surgery, University of Regensburg
| | - H Helbig
- Department of Opthalmology, University of Regensburg
| | - U Bogdahn
- Department of Neurology, Bezirksklinikum Regensburg, University of Regensburg
| | - M A Gamulescu
- Department of Opthalmology, University of Regensburg
| | - F Schlachetzki
- Department of Neurology, Bezirksklinikum Regensburg, University of Regensburg
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Altmann M, Bremer V, Nielsen S, Hamouda O. STI/HIV-Angebot und Datenerhebung in Gesundheitsämtern, 2012 - Optimierte Datennutzung durch einheitliche Indikatoren. Gesundheitswesen 2013. [DOI: 10.1055/s-0033-1337478] [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: 10/27/2022]
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18
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Ertl M, Altmann M, Torka E, Helbig H, Bogdahn U, Gamulescu A, Schlachetzki F. The retrobulbar "spot sign" as a discriminator between vasculitic and thrombo-embolic affections of the retinal blood supply. Ultraschall Med 2012; 33:E263-E267. [PMID: 23023446 DOI: 10.1055/s-0032-1312925] [Citation(s) in RCA: 16] [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] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
PURPOSE Sudden retinal blindness is a common complication of temporal arteritis (TA). Another common cause is embolic occlusion of the central retinal artery (CRA). The aim of this prospective study was to examine the diagnostic value of hyperechoic material in the CRA for the exclusion of vasculitis as a cause. The authors used orbital color-coded sonography (OCCS) for the detection of hyperechoic material. MATERIALS AND METHODS 24 patients with sudden vision loss were included in the study after the exclusion of other causes (e. g. vitreous bleeding, retinal detachment). Parallel to routine diagnostic workup, OCCS was performed in all patients. RESULTS 7 patients with a diagnosis of TA presented with different degrees of hypoperfusion in the CRA without hyperechoic material (referred to as "spot sign") detected by OCCS. Diagnostic workup in the remaining 17 patients revealed other causes of sudden vision loss, such as central retinal artery occlusion (CRAO) (12), anterior ischemic optic neuropathy (AION) (2), upstream vascular stenosis or occlusion (2) and delayed reperfusion of the CRA (1). The hyperechoic "spot sign" was visible in 10 of 12 patients (83 %) with embolic CRAO. The detection of embolic CRAO using the "spot sign" had a sensitivity of 83 % and a specificity of 100 %. The missing "spot sign" in patients with TA was a highly specific finding (p-value 0.01). CONCLUSION The detection of the "spot sign" specifically minimizes the probability of TA as a reason for sudden blindness.
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Affiliation(s)
- M Ertl
- Neurology Department, University of Regensburg
| | - M Altmann
- Department of Ophthalmology, University of Regensburg
| | - E Torka
- Neurology Department, University of Regensburg
| | - H Helbig
- Department of Ophthalmology, University of Regensburg
| | - U Bogdahn
- Neurology Department, University of Regensburg
| | - A Gamulescu
- Department of Ophthalmology, University of Regensburg
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Lemor A, Mielenz M, Altmann M, Von Borell E, Sauerwein H. ORIGINAL ARTICLE: mRNA abundance of adiponectin and its receptors, leptin and visfatin and of G-protein coupled receptor 41 in five different fat depots from sheep. J Anim Physiol Anim Nutr (Berl) 2010; 94:e96-101. [DOI: 10.1111/j.1439-0396.2010.00987.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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20
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Radun D, Bernard H, Altmann M, Schöneberg I, Bochat V, van Treeck U, Rippe RM, Grunow R, Elschner M, Biederbick W, Krause G. Preliminary case report of fatal anthrax in an injecting drug user in North-Rhine-Westphalia, Germany, December 2009. ACTA ACUST UNITED AC 2010; 15. [PMID: 20085693 DOI: 10.2807/ese.15.02.19464-en] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A fatal case of anthrax occurred in an injecting drug user in Germany, in December 2009. A potential link to similar cases in Scotland in the same time period is currently under investigation.
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Affiliation(s)
- D Radun
- Department for Infectious Disease Epidemiology, Robert Koch Institute, Berlin, Germany.
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21
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Assmann A, Altmann M, Dinger J. P708 Intrauterine devices and the risk of uterine perforations: interim results from the EURAS-IUD study. Int J Gynaecol Obstet 2009. [DOI: 10.1016/s0020-7292(09)62199-8] [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: 11/15/2022]
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22
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Gautret P, Altmann M, Parola P, Delmont J, Brouqui P. A-08 Connaissance, attitudes et pratiques des voyageurs marseillais vis-à-vis du risque de rage et de sa prévention. Med Mal Infect 2008. [DOI: 10.1016/s0399-077x(08)73068-3] [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: 11/15/2022]
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23
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Altmann M, Sauerwein H, von Borell E. Plasma leptin in growing lambs as a potential predictor for carcass composition and daily gain. Meat Sci 2006; 74:600-4. [DOI: 10.1016/j.meatsci.2006.05.013] [Citation(s) in RCA: 10] [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: 04/13/2006] [Revised: 05/08/2006] [Accepted: 05/08/2006] [Indexed: 10/24/2022]
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Altmann M, Sauerwein H, von Borell E. The relationships between leptin concentrations and body fat reserves in lambs are reduced by short-term fasting. J Anim Physiol Anim Nutr (Berl) 2006; 90:407-13. [PMID: 16958798 DOI: 10.1111/j.1439-0396.2006.00620.x] [Citation(s) in RCA: 7] [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: 11/30/2022]
Abstract
Feed deprivation decreases plasma leptin concentrations depending on the amount of body fat reserves. While a greater response was observed in lean than in fat humans and rats, a few results for ruminants are inconsistent. The objective of this study was to determine the influence of feed deprivation on plasma leptin concentration in growing lambs with different body fat reserves and on the relationship between leptin and fatness. In addition, we included other hormones (growth hormone, GH; insulin-like growth factor-I, IGF-I and insulin) involved in tissue development. Thirty male lambs of 40 kg live weight were used. Blood was sampled before and after a fasting period of 24 h. The lambs were slaughtered and dissected into several fat and lean tissues. Feed deprivation reduced plasma leptin by an average of 34.6% (p < 0.001). Obese lambs exhibited a greater decline of leptin than lean lambs (2.50 vs. 1.36 ng/ml, p < 0.05). The correlations between leptin and several fat tissues were lower in those lambs than that were fasted. This indicates that leptin concentrations after short-term fasting scarcely reflect the extent of body fat reserves but reflect more the actual metabolic situation. Body fat did not significantly influence the response of GH, IGF-I and insulin to fasting in most cases.
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Affiliation(s)
- M Altmann
- Institute of Animal Breeding and Husbandry with Veterinary Clinic, Martin-Luther-University Halle-Wittenberg, Halle, Germany.
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25
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Altmann M, Pliquett U. Prediction of intramuscular fat by impedance spectroscopy. Meat Sci 2006; 72:666-71. [DOI: 10.1016/j.meatsci.2005.08.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2005] [Revised: 08/23/2005] [Accepted: 08/28/2005] [Indexed: 10/25/2022]
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Altmann M, Sauerwein H, von Borell E. Relationship between plasma leptin concentrations and carcass composition in fattening mutton: a comparison with ultrasound results. J Anim Physiol Anim Nutr (Berl) 2005; 89:326-30. [PMID: 16138862 DOI: 10.1111/j.1439-0396.2005.00518.x] [Citation(s) in RCA: 8] [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: 11/29/2022]
Abstract
Positive relationships between circulating leptin concentrations and body fat content have been established in sheep when covering a rather broad range of age and/or body weight. The usefulness of leptin measurements for predicting carcass fat has yet to be evaluated specifically in fattening lambs. We therefore measured plasma leptin concentrations in 56 male lambs half and half Merino Mutton and Blackheaded Mutton. Subcutaneous fat thickness was measured by ultrasound 1 day before the lambs were slaughtered at 35 or 45 kg live weight. Carcass composition was determined by tissue dissection. The coefficients of correlations between leptin and the different amounts in fat depots ranged from 0.40 to 0.56 within the two live weight groups, and from 0.53 to 0.64 when taking the two groups together. Carcass fat percentage was estimated by leptin concentrations with the same accuracy (R2 = 0.34) as with ultrasound fat thickness. The accuracy was higher for leptin in the 35 kg-group whereas the accuracy was higher for ultrasound fat thickness in the 45 kg-group (R2 = 0.26 vs. 0.31). A combination of leptin and ultrasound fat thickness clearly enhanced the precision of estimation in all groups. Further investigations on the influence of factors such as breed, gender, duration of feed withdrawal or photoperiod on the association between leptin and carcass composition are necessary before the suitability of plasma leptin concentration for practical application can be evaluated.
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Affiliation(s)
- M Altmann
- Institute of Animal Breeding and Husbandry with Veterinary Clinic, Martin-Luther-University Halle-Wittenberg, Halle, Germany.
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27
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Schönert S, Abt I, Altmann M, Bakalyarov A, Barabanov I, Bauer C, Bauer M, Bellotti E, Belogurov S, Belyaev S, Bettini A, Bezrukov L, Brudanin V, Büttner C, Bolotsky V, Caldwell A, Cattadori C, Chirchenko M, Chkvorets O, Clement H, Demidova E, Di Vacri A, Eberth J, Egorov V, Farnea E, Gangapshev A, Grigoriev G, Gurentsov V, Gusev K, Hampel W, Heusser G, Hofmann W, Inzhechik L, Jochum J, Junker M, Katulina S, Kiko J, Kirpichnikov I, Klimenko A, Knöpfle K, Kochetov O, Kornoukhov V, Kotthaus R, Kusminov V, Laubenstein M, Lebedev V, Liu X, Moser HG, Nemchenok I, Pandola L, Peiffer P, Richter R, Rottler K, Rossi Alvarez C, Sandukovsky V, Schönert S, Scholl S, Schreiner J, Schwingenheuer B, Simgen H, Smolnikov A, Tikhomirov A, Tomei C, Ur C, Vasenko A, Vasiliev S, Weißhaar D, Wojcik M, Yanovich E, Yurkowski J, Zhukov S, Zuzel G. The GERmanium Detector Array (Gerda) for the search of neutrinoless ββ decays of 76Ge at LNGS. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.nuclphysbps.2005.04.014] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Altmann M, Pliquett U, Suess R, Borell EV. Prediction of carcass composition by impedance spectroscopy in lambs of similar weight. Meat Sci 2005; 70:319-27. [DOI: 10.1016/j.meatsci.2005.01.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2004] [Revised: 01/28/2005] [Accepted: 01/28/2005] [Indexed: 11/24/2022]
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Abstract
The objective of this study was to compare impedance spectroscopy with resistance measurements at a single frequency (50 kHz) for the prediction of lamb carcass composition. The impedance spectrum is usually recorded by measuring the complex impedance at various frequencies (frequency domain); however, in this study, we also applied the faster and simpler measurement in the time domain (application of a current step and measurement of the voltage response). The study was carried out on 24 male, German Black-headed Mutton lambs with an average BW of 45 kg. Frequency- and time domain-based impedance measurements were collected at 20 min and 24 h postmortem with different electrode placements. Real and imaginary parts at various frequencies were calculated from the locus diagram. Left sides were dissected into lean, fat, and bone, and right sides were ground to determine actual carcass composition. Crude fat, crude protein, and moisture were chemically analyzed on ground samples. Frequency- and time domain-based measurements did not provide the same absolute impedance values; however, the high correlations (P < 0.001) between these methods for the "real parts" showed that they ranked individuals in the same order. Most of the time domain data correlated higher to carcass composition than did the frequency domain data. The real parts of impedance showed correlations between -0.37 (P > 0.05) and -0.74 (P < 0.001) to water, crude fat, lean, and fatty tissue, whereas the relations to CP were much lower (from 0.00 to -0.47, P < 0.05). Electrode placements at different locations did not substantially improve the correlations with carcass composition. The "imaginary parts" of impedance were not suitable for the prediction of carcass composition. The highest accuracy (R2 = 0.66) was reached for the estimation of crude fat percentage by a regression equation with the time domain-based impedance measured at 24 h postmortem. Furthermore, there was not a clear superiority of measurements in a wide frequency range over a single frequency measurement at 50 kHz for the prediction of carcass composition. Even though we calculated the impedance at 50 kHz based on the locus diagram, which allowed for a high precision for predicting this impedance trait, single-frequency impedance devices typically used in practice cannot record the locus diagram and, therefore, exhibit a greater amount of uncertainty.
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Affiliation(s)
- M Altmann
- Institute of Animal Breeding and Husbandry with Veterinary Clinic, Faculty of Agriculture, Martin-Luther-University, Halle, D-06108 Germany.
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Abstract
The P(y) is a parameter which assesses the integrity of the cell membranes. It is a direct indicator for the volume fraction of cells surrounded by insulating cell membranes. The P(y) has been shown to correlate well with meat quality parameters like the drip loss or pH. It is a useful parameter for the discrimination between normal suited meat and PSE meat. The measurement is instantaneous and nondestructive. Due to aging of meat, P(y) depends on the time post mortem. It shows the highest significance between 4 and 24 h p.m.
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Affiliation(s)
- U Pliquett
- University of Bielefeld, Faculty of Chemistry, D-33615 Bielefeld, Germany
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31
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Altmann M. Selling your AED program to management. OCCUPATIONAL HEALTH & SAFETY (WACO, TEX.) 2001; 70:82-4, 86, 97. [PMID: 11692572] [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] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Affiliation(s)
- M Altmann
- Survivalink Corporation, Minneapolis, Minn., USA
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Abstract
The mitochondrial tRNA gene for lysine was analyzed in 11 different marsupial mammals. Whereas its location is conserved when compared with other vertebrate mitochondrial genomes, its primary sequence and inferred secondary structure are highly unusual and variable. For example, eight species lack the expected anticodon. Because the corresponding transcripts are not altered by any RNA-editing mechanism, the lysyl-tRNA gene seems to represent a mitochondrial pseudogene. Purification of marsupial mitochondria and in vitro aminoacylation of isolated tRNAs with lysine, followed by analysis of aminoacylated tRNAs, show that a nuclear-encoded tRNA(Lys) is associated with marsupial mitochondria. We conclude that a functional tRNA(Lys) encoded in the nuclear genome is imported into mitochondria in marsupials. Thus, tRNA import is not restricted to plant, yeast, and protozoan mitochondria but also occurs also in mammals.
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Affiliation(s)
- M Dörner
- Max-Planck-Institute for Evolutionary Anthropology, D-04105 Leipzig, Germany
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Dominguez D, Kislig E, Altmann M, Trachsel H. Structural and functional similarities between the central eukaryotic initiation factor (eIF)4A-binding domain of mammalian eIF4G and the eIF4A-binding domain of yeast eIF4G. Biochem J 2001; 355:223-30. [PMID: 11256967 PMCID: PMC1221730 DOI: 10.1042/0264-6021:3550223] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The translation eukaryotic initiation factor (eIF)4G of the yeast Saccharomyces cerevisiae interacts with the RNA helicase eIF4A (a member of the DEAD-box protein family; where DEAD corresponds to Asp-Glu-Ala-Asp) through a C-terminal domain in eIF4G (amino acids 542-883). Mammalian eIF4G has two interaction domains for eIF4A, a central domain and a domain close to the C-terminus. This raises the question of whether eIF4A binding to eIF4G is conserved between yeast and mammalian cells or whether it is different. We isolated eIF4G1 mutants defective in eIF4A binding and showed that these mutants are strongly impaired in translation and growth. Extracts from mutants displaying a temperature-sensitive phenotype for growth have low in vitro translation activity, which can be restored by addition of the purified eIF4G1-eIF4E complex, but not by eIF4E alone. Analysis of mutant eIF4G(542-883) proteins defective in eIF4A binding shows that the interaction of yeast eIF4A with eIF4G1 depends on amino acid motifs that are conserved between the yeast eIF4A-binding site and the central eIF4A-binding domain of mammalian eIF4G. We show that mammalian eIF4A binds tightly to yeast eIF4G1 and, furthermore, that mutant yeast eIF4G(542-883) proteins, which do not bind yeast eIF4A, do not interact with mammalian eIF4A. Despite the conservation of the eIF4A-binding site in eIF4G and the strong sequence conservation between yeast and mammalian eIF4A (66% identity; 82% similarity at the amino acid level) mammalian eIF4A does not substitute for the yeast factor in vivo and is not functional in a yeast in vitro translation system.
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Affiliation(s)
- D Dominguez
- Institute for Biochemistry and Molecular Biology, University of Berne, Bühlstrasse 28, CH-3012 Bern, Switzerland
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Steffen W, Köhler B, Altmann M, Scherf U, Stitzer K, zur Loye HC, Bunz UH. Conjugated organometallic polymers containing Vollhardt's cyclobutadiene complex: aggregation and morphologies. Chemistry 2001; 7:117-26. [PMID: 11205003 DOI: 10.1002/1521-3765(20010105)7:1<117::aid-chem117>3.0.co;2-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Organometallic polymers were prepared by acyclic diyne metathesis (ADIMET) or by Pd-catalyzed coupling of 1,3-diethynylcyclobutadiene(cyclopentadienyl)cobalt with a suitably substituted diiodobenzene. The polymers obtained by Heck coupling show a degree of polymerization (Pn) of 20-60. The monomers for ADIMET were made by the Pd-catalyzed coupling of [1,3-bis(trimethylsilylethynyl)-2,4-bis(trimethylsilyl)cyclobutadiene](cyclopentadienyl)cobalt to 1-bromo-2,5-dialkyl-4-propynylbenzenes in the presence of KOH in yields of 40-48%. The monomers carry hexyl, ethylhexyl, and (S)-3,7-dimethyloctyl side chains. Polymerization of the propynylated monomers furnishes organometallic polymers with a Pn of up to 230 arylene-ethynylene units. The polymers were fully characterized by polarizing microscopy, transmission electron microscopy, circular dichroism, differential scanning calorimetry, and X-ray diffraction (XRD). They show nematic, lyotropic liquid crystalline phases as well as chiroptical properties from which aggregation in poor solvents and in the solid state can be concluded. Lamellar or irregular honeycomb-shaped morphologies in these organometallic polymers can be detected by electron microscopy.
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Affiliation(s)
- W Steffen
- Department of Chemistry and Biochemistry, The University of South Carolina, Columbia 29208, USA
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Sellers TA, Weaver TW, Phillips B, Altmann M, Rich SS. Environmental factors can confound identification of a major gene effect: results from a segregation analysis of a simulated population of lung cancer families. Genet Epidemiol 2000; 15:251-62. [PMID: 9593112 DOI: 10.1002/(sici)1098-2272(1998)15:3<251::aid-gepi4>3.0.co;2-7] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Proper control of environmental factors can be crucial to the identification of genes that influence susceptibility to a complex trait, especially for a trait such as lung cancer, for which the environmental factor (smoking) accounts for a significant etiologic fraction of the disease. An earlier segregation analysis of 337 Louisiana families, which incorporated direct measure of tobacco consumption, provided evidence for autosomal codominant inheritance of a major gene that influenced age at onset of lung cancer. Subsequent analyses were performed in which the families were stratified into two subsets based on birth cohort of the proband; results suggested the presence of heterogeneity that were postulated to reflect the influence of cohort trends in tobacco consumption. To evaluate this hypothesis further, we simulated a population of three-generation pedigrees in which an autosomal dominant mode of susceptibility to lung cancer was transmitted, but tobacco use varied across generations corresponding to published trends in smoking. A total of 200,000 individuals in families of various sizes, ages, and cigarette smoking habits were simulated from 1900 to 1980. From this population, 324 families (2,405 individuals) with 380 cases of lung cancer were ascertained through 328 lung cancer probands. Complex segregation analysis was performed using the REGTL program of S.A.G.E. in which pack-years of tobacco exposure were incorporated directly into the likelihood calculations. Although the no major gene, environmental, and Mendelian recessive hypotheses were rejected, both dominant and codominant transmission provided a good fit to the data. Thus in a population of simulated families with autosomal dominant susceptibility to lung cancer, intergenerational differences in tobacco consumption led to the detection of autosomal codominant transmission as an acceptable hypothesis. These results underscore the potential danger of segregation analysis of complex traits in which exposure to known environmental influences may differ across generations.
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Affiliation(s)
- T A Sellers
- Division of Epidemiology, School of Public Health, Institute of Human Genetics, University of Minnesota, Minneapolis 55454-1015, USA
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36
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Abstract
Mutations of SALL1 related to spalt of Drosophila have been found to cause Townes-Brocks syndrome, suggesting a function of SALL1 for the development of anus, limbs, ears, and kidneys. No function is yet known for SALL2, another human spalt-like gene. The structure of SALL2 is different from SALL1 and all other vertebrate spalt-like genes described in mouse, Xenopus, and Medaka, suggesting that SALL2-like genes might also exist in other vertebrates. Consistent with this hypothesis, we isolated and characterized a SALL2 homologous mouse gene, Msal-2. In contrast to other vertebrate spalt-like genes both SALL2 and Msal-2 encode only three double zinc finger domains, the most carboxyterminal of which only distantly resembles spalt-like zinc fingers. The evolutionary conservation of SALL2/Msal-2 suggests that two lines of sal-like genes with presumably different functions arose from an early evolutionary duplication of a common ancestor gene. Msal-2 is expressed throughout embryonic development but also in adult tissues, predominantly in brain. However, the function of SALL2/Msal-2 still needs to be determined.
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Affiliation(s)
- J Kohlhase
- Institut für Humangenetik der Universität Göttingen, Heinrich-Düker-Weg 12, D-37073 Göttingen, Germany.
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Kohlhase J, Hausmann S, Stojmenovic G, Dixkens C, Bink K, Schulz-Schaeffer W, Altmann M, Engel W. SALL3, a new member of the human spalt-like gene family, maps to 18q23. Genomics 1999; 62:216-22. [PMID: 10610715 DOI: 10.1006/geno.1999.6005] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [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
spalt (sal) of Drosophila melanogaster is an important developmental regulator gene and encodes a zinc finger protein of unusual but characteristic structure. Two human sal-like genes have been isolated so far, SALL1 on chromosome 16q12.1 and SALL2 on chromosome 14q11.1-q12.1. Truncating mutations of SALL1 have been shown to cause Townes-Brocks syndrome and are thought to result in SALL1 haploinsufficiency. Sequence comparison of SALL1 to the related genes Msal in mouse and Xsal-1 in Xenopus laevis suggested that SALL1 was not the human orthologue of Msal and Xsal-1. By database searching and genomic cloning, we isolated an EST and a corresponding human cosmid clone, which contain coding sequence of a human gene highly similar to mouse Msal. This gene, named SALL3, was found to be expressed in different regions of human fetal brain and in different adult human tissues. The chromosomal localization of SALL3 at 18q23 suggests that haploinsufficiency of this gene might contribute to the phenotype of patients with 18q deletion syndrome.
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Affiliation(s)
- J Kohlhase
- Institut für Humangenetik, Universität Göttingen, Germany.
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Dominguez D, Altmann M, Benz J, Baumann U, Trachsel H. Interaction of translation initiation factor eIF4G with eIF4A in the yeast Saccharomyces cerevisiae. J Biol Chem 1999; 274:26720-6. [PMID: 10480875 DOI: 10.1074/jbc.274.38.26720] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [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: 11/06/2022] Open
Abstract
Eukaryotic initiation factor (eIF) 4A is an essential protein that, in conjunction with eIF4B, catalyzes the ATP-dependent melting of RNA secondary structure in the 5'-untranslated region of mRNA during translation initiation. In higher eukaryotes, eIF4A is assumed to be recruited to the mRNA through its interaction with eIF4G. However, the failure to detect this interaction in yeast brought into question the generality of this model. The work presented here demonstrates that yeast eIF4G interacts with eIF4A both in vivo and in vitro. The eIF4A-binding site was mapped to amino acids 542-883 of yeast eIF4G1. Expression in yeast cells of the eIF4G1 domain that binds eIF4A results in cell growth inhibition, and addition of this domain to an eIF4A-dependent in vitro system inhibits translation in a dose-dependent manner. Both in vitro translation and cell growth can be specifically restored by increasing the eIF4A concentration. These data demonstrate that yeast eIF4A and eIF4G interact and suggest that this interaction is required for translation and cell growth.
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Affiliation(s)
- D Dominguez
- Institute for Biochemistry and Molecular Biology, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland.
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Danaie P, Altmann M, Hall MN, Trachsel H, Helliwell SB. CLN3 expression is sufficient to restore G1-to-S-phase progression in Saccharomyces cerevisiae mutants defective in translation initiation factor eIF4E. Biochem J 1999; 340 ( Pt 1):135-41. [PMID: 10229668 PMCID: PMC1220231] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
The essential cap-binding protein (eIF4E) of Saccharomyces cerevisiae is encoded by the CDC33 (wild-type) gene, originally isolated as a mutant, cdc33-1, which arrests growth in the G1 phase of the cell cycle at 37 degrees C. We show that other cdc33 mutants also arrest in G1. One of the first events required for G1-to-S-phase progression is the increased expression of cyclin 3. Constructs carrying the 5'-untranslated region of CLN3 fused to lacZ exhibit weak reporter activity, which is significantly decreased in a cdc33-1 mutant, implying that CLN3 mRNA is an inefficiently translated mRNA that is sensitive to perturbations in the translation machinery. A cdc33-1 strain expressing either stable Cln3p (Cln3-1p) or a hybrid UBI4 5'-CLN3 mRNA, whose translation displays decreased dependence on eIF4E, arrested randomly in the cell cycle. In these cells CLN2 mRNA levels remained high, indicating that Cln3p activity is maintained. Induction of a hybrid UBI4 5'-CLN3 message in a cdc33-1 mutant previously arrested in G1 also caused entry into a new cell cycle. We conclude that eIF4E activity in the G1-phase is critical in allowing sufficient Cln3p activity to enable yeast cells to enter a new cell cycle.
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Affiliation(s)
- P Danaie
- Institute for Biochemistry and Molecular Biology, University of Berne, Bühlstrasse 28, CH-3012 Bern, Switzerland
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Leonhardt SA, Altmann M, Edwards DP. Agonist and antagonists induce homodimerization and mixed ligand heterodimerization of human progesterone receptors in vivo by a mammalian two-hybrid assay. Mol Endocrinol 1998; 12:1914-30. [PMID: 9849965 DOI: 10.1210/mend.12.12.0210] [Citation(s) in RCA: 25] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
This study utilizes the mammalian two-hybrid system to examine the role of ligand in the dimerization of human progesterone receptor (hPR). The GAL4 DNA-binding domain and the herpes simplex virus VP16 transactivation domain were fused to the amino terminus of full-length hPR (both the A and B isoforms) to produce chimeric proteins. PR dimerization was detected by the ability of cotransfected GAL4/PR and VP16/PR chimeras in COS cells to induce expression of a reporter gene under the control of GAL4-binding sites (pG5CAT). Hormone agonist-dependent interactions were observed between the two like isoforms of PR (A-A and B-B) and between PR-A and PR-B (A-B), indicating that hormone can stimulate the formation of the three possible dimeric forms of PR within cells. In contrast, neither type I (ZK98299) nor type II (RU486, ZK112993) progestin antagonists stimulated interaction between these same hybrid PR proteins. However, activation of the VP16/PR chimera by antagonists on a progesterone response element-controlled reporter gene (DHRE-E1b-CAT) was only a fraction (4-13%) of that stimulated by agonist R5020. One possibility for the failure to detect an induction in the two-hybrid assay is antagonist-induced repression of the activity of the VP16/PR fusion protein rather than a failure of antagonists to stimulate interaction between the hybrid proteins. To test this idea, an UP-1 carboxyl-terminal truncation mutant of PR was used to construct the two-hybrid proteins. PR-UP-1 selectively binds antagonists, but not agonists, and is fully activated in response to antagonists. Both types of progestin antagonists stimulated interactions between GAL4/PR(UP-1) and VP16/PR(UP-1) hybrid proteins, indicating that antagonists are capable of stimulating PR dimerization in cells and do not function by disrupting or preventing dimerization. To determine whether PR bound to an antagonist can dimerize in whole cells with PR bound to agonist, GAL4/PR(UP-1) was paired in the two-hybrid assay with a VP16/PR fusion protein harboring a point mutation in PR at amino acid 722 (Gly-Cys) that specifically binds progestin agonist but not antagonist. Neither R5020 nor RU486 alone stimulated interaction between these ligand-specific PR hybrid proteins. However, strong interaction was detected by addition of both agonist and antagonists, indicating the formation of mixed ligand heterodimers and that both PR partners require ligand for dimerization to occur. Based on electrophoretic gel mobility shift assays (EMSAs), these heterodimers appear to have substantially reduced DNA binding activity. Progestin antagonists inhibit agonist activation of PR at concentrations that are too low to be accounted for by a simple competition mechanism for binding to PR. We propose that antiprogestin inactivation of PR in trans by heterodimerization contributes to the biological potency of these compounds.
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Affiliation(s)
- S A Leonhardt
- Department of Pathology, University of Colorado Health Sciences Center, Denver 80262, USA
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41
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Niederberger N, Trachsel H, Altmann M. The RNA recognition motif of yeast translation initiation factor Tif3/eIF4B is required but not sufficient for RNA strand-exchange and translational activity. RNA 1998; 4:1259-1267. [PMID: 9769100 PMCID: PMC1369698 DOI: 10.1017/s1355838298980487] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The Saccharomyces cerevisiae TIF3 gene encodes a 436-amino acid (aa) protein that is the yeast homologue of mammalian translation Initiation factor eIF4B. Tif3p can be divided into three parts, the N-terminal region with an RNA recognition motif (RRM) (aa 1-182), followed in the middle part by a sevenfold repeat of 26 amino acids rich in basic and acidic residues (as 183-350), and a C-terminal region without homology to any known sequence (aa 351-436). We have analyzed several Tif3 proteins with deletions at their N and C termini for their ability (1) to complement a tif3delta strain in vivo, (2) to stimulate Tif3-dependent translation extracts, (3) to bind to single-stranded RNA, and (4) to catalyze RNA strand-exchange in vitro. Here we report that yeast Tif3/eIF4B contains at least two RNA binding domains able to bind to single-stranded RNA. One is located in the N-terminal region of the protein carrying the RRM, the other in the C-terminal two-thirds region of Tif3p. The RRM-containing domain and three of the seven repeat motifs are essential for RNA strand-exchange activity of Tif3p and translation in vitro and for complementation of a tif3delta strain, suggesting an important role for RNA strand-exchange activity in translation.
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Affiliation(s)
- N Niederberger
- Institute for Biochemistry and Molecular Biology, University of Berne, Switzerland
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42
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Boonyaratanakornkit V, Melvin V, Prendergast P, Altmann M, Ronfani L, Bianchi ME, Taraseviciene L, Nordeen SK, Allegretto EA, Edwards DP. High-mobility group chromatin proteins 1 and 2 functionally interact with steroid hormone receptors to enhance their DNA binding in vitro and transcriptional activity in mammalian cells. Mol Cell Biol 1998; 18:4471-87. [PMID: 9671457 PMCID: PMC109033 DOI: 10.1128/mcb.18.8.4471] [Citation(s) in RCA: 263] [Impact Index Per Article: 10.1] [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] [Received: 10/06/1997] [Accepted: 05/04/1998] [Indexed: 02/08/2023] Open
Abstract
We previously reported that the chromatin high-mobility group protein 1 (HMG-1) enhances the sequence-specific DNA binding activity of progesterone receptor (PR) in vitro, thus providing the first evidence that HMG-1 may have a coregulatory role in steroid receptor-mediated gene transcription. Here we show that HMG-1 and the highly related HMG-2 stimulate DNA binding by other steroid receptors, including estrogen, androgen, and glucocorticoid receptors, but have no effect on DNA binding by several nonsteroid nuclear receptors, including retinoid acid receptor (RAR), retinoic X receptor (RXR), and vitamin D receptor (VDR). As highly purified recombinant full-length proteins, all steroid receptors tested exhibited weak binding affinity for their optimal palindromic hormone response elements (HREs), and the addition of purified HMG-1 or -2 substantially increased their affinity for HREs. Purified RAR, RXR, and VDR also exhibited little to no detectable binding to their cognate direct repeat HREs but, in contrast to results with steroid receptors, the addition of HMG-1 or HMG-2 had no stimulatory effect. Instead, the addition of purified RXR enhanced RAR and VDR DNA binding through a heterodimerization mechanism and HMG-1 or HMG-2 had no further effect on DNA binding by RXR-RAR or RXR-VDR heterodimers. HMG-1 and HMG-2 (HMG-1/-2) themselves do not bind to progesterone response elements, but in the presence of PR they were detected as part of an HMG-PR-DNA ternary complex. HMG-1/-2 can also interact transiently in vitro with PR in the absence of DNA; however, no direct protein interaction was detected with VDR. These results, taken together with the fact that PR can bend its target DNA and that HMG-1/-2 are non-sequence-specific DNA binding proteins that recognize DNA structure, suggest that HMG-1/-2 are recruited to the PR-DNA complex by the combined effect of transient protein interaction and DNA bending. In transient-transfection assays, coexpression of HMG-1 or HMG-2 increased PR-mediated transcription in mammalian cells by as much as 7- to 10-fold without altering the basal promoter activity of target reporter genes. This increase in PR-mediated gene activation by coexpression of HMG-1/-2 was observed in different cell types and with different target promoters, suggesting a generality to the functional interaction between HMG-1/-2 and PR in vivo. Cotransfection of HMG-1 also increased reporter gene activation mediated by other steroid receptors, including glucocorticoid and androgen receptors, but it had a minimal influence on VDR-dependent transcription in vivo. These results support the conclusion that HMG-1/-2 are coregulatory proteins that increase the DNA binding and transcriptional activity of the steroid hormone class of receptors but that do not functionally interact with certain nonsteroid classes of nuclear receptors.
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MESH Headings
- Animals
- COS Cells
- Chloramphenicol O-Acetyltransferase/genetics
- DNA/metabolism
- Genes, Reporter
- High Mobility Group Proteins/genetics
- High Mobility Group Proteins/metabolism
- Humans
- Mammals
- Receptors, Androgen/metabolism
- Receptors, Calcitriol/metabolism
- Receptors, Glucocorticoid/metabolism
- Receptors, Progesterone/genetics
- Receptors, Progesterone/metabolism
- Receptors, Steroid/genetics
- Receptors, Steroid/metabolism
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/isolation & purification
- Recombinant Fusion Proteins/metabolism
- Repetitive Sequences, Nucleic Acid
- Transcription, Genetic
- Transcriptional Activation
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Affiliation(s)
- V Boonyaratanakornkit
- Department of Pathology & Molecular Biology Program, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA
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Abstract
This paper analyzes the large population dynamics of an infectious disease model with contacts that occur during partnerships. The model allows for concurrent partnerships following a very broad class of dynamic laws. Previous work, with a stochastic version of the model, computed the reproductive number, the initial growth rate, and the final size. In the present paper, the deterministic system that is the limit for large populations is constructed. The construction is unusual in requiring two different scaling factors. Next, the approximation used by Watts and May for a related model is compared with the exact solution. This approximation is most accurate at the beginning of the epidemic and when partnerships are short. Lastly, the model is generalized to allow dependencies among partnerships. This generalization permits proportional mixing with an arbitrary distribution on the number of partners.
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Affiliation(s)
- M Altmann
- Division of Health Computer Sciences, University of Minnesota, Minneapolis 55455, USA.
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Berset C, Trachsel H, Altmann M. The TOR (target of rapamycin) signal transduction pathway regulates the stability of translation initiation factor eIF4G in the yeast Saccharomyces cerevisiae. Proc Natl Acad Sci U S A 1998; 95:4264-9. [PMID: 9539725 PMCID: PMC22477 DOI: 10.1073/pnas.95.8.4264] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.3] [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] [Indexed: 02/07/2023] Open
Abstract
Initiation factor eIF4G is an essential protein required for initiation of mRNA translation via the 5' cap-dependent pathway. It interacts with eIF4E (the mRNA 5' cap-binding protein) and serves as an anchor for the assembly of further initiation factors. With treatment of Saccharomyces cerevisiae with rapamycin or with entry of cells into the diauxic phase, eIF4G is rapidly degraded, whereas initiation factors eIF4E and eIF4A remain stable. We propose that nutritional deprivation or interruption of the TOR signal transduction pathway induces eIF4G degradation.
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Affiliation(s)
- C Berset
- Institute for Biochemistry and Molecular Biology, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
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45
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Altmann M. Search for consensus on genetic engineering. Nature 1998; 392:13. [PMID: 9510236 DOI: 10.1038/32025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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46
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Abstract
Translation initiation factor-dependent extracts are prepared from Saccharomyces cerevisiae strains that have no or reduced activity of a translation initiation factor. Elimination of factor activity can be achieved by deletion of the gene encoding the factor if it is not essential for the survival of the strain. If the gene is essential it is placed under the control of the regulatable GAL1 promoter and its expression is shut off in vivo. Alternatively, a temperature-sensitive mutation can be introduced into the gene and the activity of the gene product eliminated in vitro by preincubation of the extract at the nonpermissive temperature. Factor-dependent extracts can be complemented in vitro with purified initiation factor preparations isolated from S. cerevisiae or from Escherichia coli cells expressing them from plasmid-encoded constructs. To simplify the purification of the factors they may be expressed as fusion proteins with N- or C-terminal tags. Initiation factor-dependent extracts can be used to study initiation factor structure-function relationships and initiation factor requirements for specific mRNA translation.
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Affiliation(s)
- M Altmann
- Institut für Biochemie und Molekularbiologie, Universität Bern, Switzerland
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47
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Altmann M, Schmitz N, Berset C, Trachsel H. A novel inhibitor of cap-dependent translation initiation in yeast: p20 competes with eIF4G for binding to eIF4E. EMBO J 1997; 16:1114-21. [PMID: 9118949 PMCID: PMC1169710 DOI: 10.1093/emboj/16.5.1114] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.2] [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: 02/04/2023] Open
Abstract
In the yeast Saccharomyces cerevisiae a small protein named p20 is found associated with translation initiation factor eIF4E, the mRNA cap-binding protein. We demonstrate here that p20 is a repressor of cap-dependent translation initiation. p20 shows amino acid sequence homology to a region of eIF4G, the large subunit of the cap-binding protein complex eIF4F, which carries the binding site for eIF4E. Both, eIF4G and p20 bind to eIF4E and compete with each other for binding to eIF4E. The eIF4E-p20 complex can bind to the cap structure and inhibit cap-dependent but not cap-independent translation initiation: the translation of a mRNA with the 67 nucleotide omega sequence of tobacco mosaic virus in its 5' untranslated region (which was previously shown to render translation cap-independent) is not inhibited by p20. Whereas the translation of the same mRNA lacking the omega sequence is strongly inhibited by p20. Disruption of CAF20, the gene encoding p20, stimulates the growth of yeast cells, overexpression of p20 causes slower growth of yeast cells. These results show that p20 is a regulator of eIF4E activity which represses cap-dependent initiation of translation by interfering with the interaction of eIF4E with eIF4G, e.g. the formation of the eIF4F-complex.
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Affiliation(s)
- M Altmann
- Institute for Biochemistry and Molecular Biology, University of Bern, Switzerland
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48
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Boult C, Altmann M, Gilbertson D, Yu C, Kane RL. Decreasing disability in the 21st century: the future effects of controlling six fatal and nonfatal conditions. Am J Public Health 1996; 86:1388-93. [PMID: 8876506 PMCID: PMC1380648 DOI: 10.2105/ajph.86.10.1388] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.0] [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: 02/02/2023]
Abstract
OBJECTIVES This study assessed the effects of reducing fatal and nonfatal health conditions on the number of functionally limited older Americans in the coming decades. METHODS Data from the 1990 census and the Longitudinal Study of Aging were used to project the number of functionally limited older Americans from 2001 to 2049, assuming 1% biennial reductions in five conditions that shorten life expectancy (coronary artery disease, stroke, cancer, diabetes, and confusion) and one condition that decreases functional ability (arthritis). RESULTS Decreasing the prevalence of arthritis by 1% every 2 years would lead to a much greater reduction in functional limitation between 2001 and 2049 (4 million person-years) than would decreasing any of the other conditions by the same amount. Decreases in two fatal conditions (cancer and coronary artery disease) would lead to increases in functional limitation (0.9 and 0.1 million person-years, respectively). CONCLUSIONS Advances against common nonfatal disabling conditions would be more effective than advances against fatal conditions in blunting the large increase in the functionally limited older population anticipated in the 21st century.
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Affiliation(s)
- C Boult
- Department of Family Practice and Community Health, University of Minnesota Medical School, Minneapolis, USA
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Beck CA, Zhang Y, Altmann M, Weigel NL, Edwards DP. Stoichiometry and site-specific phosphorylation of human progesterone receptor in native target cells and in the baculovirus expression system. J Biol Chem 1996; 271:19546-55. [PMID: 8702648 DOI: 10.1074/jbc.271.32.19546] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [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: 02/01/2023] Open
Abstract
Human progesterone receptor (PR) in T47D breast cancer cells is phosphorylated on nine different serine residues; three are hormone-inducible (Ser102, Ser294, and Ser345), while others are basal but hormone-stimulated. In the present study, we have compared the phosphorylation state of native and recombinant PR expressed in a baculovirus insect cell system. Stoichiometric measurements showed that unliganded native PR in T47D cells was approximately 50% phosphorylated ( approximately 4 phosphates/PR) and became essentially 100% phosphorylated ( approximately 9 phosphates/PR) when bound to hormone. Unliganded PR expressed in Sf9 insect cells was phosphorylated with a similar stoichiometry ( approximately 3 phosphates/PR), but the phosphate content did not change with hormone addition. Site-specific phosphorylation analyzed by tryptic phosphopeptide mapping and manual peptide sequencing revealed that expressed PR bound to hormone in the Sf9 insect cells was phosphorylated on all the same sites as hormone-treated PR in T47D cells. Only minor differences were detected in the relative proportion of three sites (two basal sites and Ser345) and phosphorylation did not occur on alternate sites. Interestingly, unliganded baculovirus-expressed PR was constitutively phosphorylated on hormone inducible sites and was phosphorylated on basal sites to the same extent as hormone treated PR. Thus, in the absence of hormone, the phosphorylation state of baculovirus-expressed PR resembled that of the hyperphosphorylated native PR. In contrast to native PR, the expressed receptor in cytosols of Sf9 cells did not form a large oligomeric complex suggesting that hyperphosphorylation may be due to dissociation of the complex in the absence of hormone. This study demonstrating phosphorylation on correct sites with a stoichiometry similar to that of native PR indicates that overexpressed PR in the baculovirus system is suitable for in vitro structure/function studies.
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Affiliation(s)
- C A Beck
- Department of Pathology, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA
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Englmeier KH, Herpers R, Künzer I, Obermaier M, Altmann M. Displacement correction and surface reconstruction of the retina using scanning laser ophthalmoscopic images. Int J Biomed Comput 1996; 42:191-204. [PMID: 8894775 DOI: 10.1016/0020-7101(96)01197-x] [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] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A method for a three-dimensional surface reconstruction of the retina in the area of the papilla is presented. The surface reconstruction is based on a sequence of discrete gray-level images of the retina recorded by a scanning laser ophthalmoscope (SLO). The underlying assumption of the surface reconstruction algorithm developed here is that the depth information is also encoded in the brightness values of the single pixels in addition to the ordinary spatial 2D information. The brightness of an image position depends on the degree of reflection of a confocal laser beam. Only those surface structures located directly in the focus plane of the confocal laser beam produce a high response to the laser light. The displacements between the single images of a sequence are considered to be approximately linear and are corrected by applying the cepstrum technique. The depth is estimated from the volumetric representation of the image sequence by searching for the maximal value of the brightness within a computed depth profile, at every image position. In the resulting images, disturbances occurring during the recording cause incorrect local estimations of the depth. These local disturbances are corrected by applying specially developed surface improvement processes. The work is concluded with a comparison of several different approaches to reduce the noise and disturbances in SLO image data.
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Affiliation(s)
- K H Englmeier
- GSF-Forschungszentrum für Umwelt und Gesundheit, Institut für Medizinische Informatik und Systemforschung Neuherberg, Oberschleissheim, Germany
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