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Falk N, Reid T, Skoyles A, Grgicak-Mannion A, Drouillard K, Weisener CG. Microbial metatranscriptomic investigations across contaminant gradients of the Detroit River. Sci Total Environ 2019; 690:121-131. [PMID: 31284186 DOI: 10.1016/j.scitotenv.2019.06.451] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 06/25/2019] [Accepted: 06/26/2019] [Indexed: 06/09/2023]
Abstract
Microbial community function in freshwater sediments is influenced by the presence and persistence of anthropogenic pollutants, yet simultaneously imposes significant control on their transformation. Thus, microbes provide valuable ecosystem services in terms of biodegradation and bioindicators of compromised habitats. From a remediation perspective it is valuable to leverage the suite of microbial genes at the transcriptional level that are active in either natural versus stressed environments to provide insight into the cycling and fate of contaminants. Metatranscriptomic analysis of total bacterial and archaeal messenger RNA (mRNA) is a useful tool in this facet and was applied to sediments sampled from the Detroit River; a binational Area of Concern (AOC) in the Great Lakes. Previously established sediment surveys and modelling delineated the river into contaminant gradients based on concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and metals. Differential expression analysis through DESeq2 revealed that microbial transcripts associated with nitrate reduction, methanogenesis, and beta-oxidation were significant in legacy polluted sediments and linked with energetic pathways key in the generation of cellular currencies (acetyl-CoA, succinyl-CoA). Gluconeogenesis and polyester synthesis also showed high abundance in contaminated regions, along with increased expression of stress response genes and transposons, despite decreases in community α-diversity. Aromatic cleavage genes were detected, but in low abundance across the contaminant gradient. These results suggest that microbial communities within the Detroit River exploit unique anabolic and catabolic pathways to derive and store energy from legacy organic contaminants while simultaneously recruiting stress-response and gene transfer mechanisms to cope with xenobiotic pressures. By coupling well-resolved chemical datasets with metatranscriptomics, this study adds to the spatial understanding of in-situ microbial activities in pristine and perturbed freshwater sediments.
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Affiliation(s)
- N Falk
- Great Lakes Institute for Environmental Research, University of Windsor, 2990 Riverside Dr W, Windsor, ON N9C 1A2, Canada.
| | - T Reid
- Great Lakes Institute for Environmental Research, University of Windsor, 2990 Riverside Dr W, Windsor, ON N9C 1A2, Canada
| | - A Skoyles
- Great Lakes Institute for Environmental Research, University of Windsor, 2990 Riverside Dr W, Windsor, ON N9C 1A2, Canada
| | - A Grgicak-Mannion
- Great Lakes Institute for Environmental Research, University of Windsor, 2990 Riverside Dr W, Windsor, ON N9C 1A2, Canada
| | - K Drouillard
- Great Lakes Institute for Environmental Research, University of Windsor, 2990 Riverside Dr W, Windsor, ON N9C 1A2, Canada
| | - C G Weisener
- Great Lakes Institute for Environmental Research, University of Windsor, 2990 Riverside Dr W, Windsor, ON N9C 1A2, Canada
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Falk N, Joachimsthaler A, Kessler K, Lux UT, Noegel AA, Kremers J, Brandstätter JH, Gießl A, Falk N, Joachimsthaler A, Kessler K, Lux UT, Noegel AA, Kremers J, Brandstätter JH, Gießl A. Lack of a Retinal Phenotype in a Syne-2/Nesprin-2 Knockout Mouse Model. Cells 2019; 8:cells8101238. [PMID: 31614616 PMCID: PMC6830317 DOI: 10.3390/cells8101238] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/04/2019] [Accepted: 10/10/2019] [Indexed: 01/24/2023] Open
Abstract
Syne-2 (also known as Nesprin-2) is a member of a family of proteins that are found primarily in the outer nuclear membrane, as well as other subcellular compartments. Syne-2 contains a C-terminal KASH transmembrane domain and is part of a protein network that associates the nuclear envelope to the cytoskeleton via the binding to actin filaments. Syne-2 plays a role in nuclear migration, nuclear positioning during retinal development, and in ciliogenesis. In a previous study, we showed a connection between Syne-2 and the multifunctional scaffold protein Pericentrin (Pcnt). The elimination of the interaction of Syne-2 and Pcnt showed defects in nuclear migration and the formation of outer segments during retinal development, as well as disturbances in centrosomal migration at the beginning of ciliogenesis in general. In this study, the Syne-2 KO mouse model Nesprin-2△ABD (Syne-2tm1Ngl, MGI) with special attention to Pcnt and ciliogenesis was analyzed. We show reduced expression of Syne-2 in the retina of the Syne-2 KO mouse but found no significant structural—and only a minor functional—phenotype. For the first time, detailed expression analyses showed an expression of a Syne-2 protein larger than 400 kDa (~750 kDa) in the Syne-2/Nesprin-2 KO mouse. In conclusion, the lack of an overt phenotype in Syne-2/Nesprin-2 KO mice suggests the usage of alternative translational start sites, producing Syne-2 splice variants with an intact Pcnt interaction site. Nevertheless, deletion of the actin-binding site in the Syne-2/Nesprin-2 KO mouse revealed a high variability in scotopic oscillatory potentials assuming a novel function of Syne-2 in synchronizing inner retinal processes.
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Affiliation(s)
- Nathalie Falk
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany.
| | - Anneka Joachimsthaler
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany.
- Department of Ophthalmology, University Hospital Erlangen, 91054 Erlangen, Germany.
| | - Kristin Kessler
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany.
| | - Uwe Thorsten Lux
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany.
| | - Angelika Anna Noegel
- Institute of Biochemistry I; Medical Faculty, University Hospital, University of Cologne, 50931 Cologne, Germany.
| | - Jan Kremers
- Department of Ophthalmology, University Hospital Erlangen, 91054 Erlangen, Germany.
| | | | - Andreas Gießl
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany.
- Department of Ophthalmology, University Hospital Erlangen, 91054 Erlangen, Germany.
| | - Nathalie Falk
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Anneka Joachimsthaler
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
- Department of Ophthalmology, University Hospital Erlangen, 91054 Erlangen, Germany
| | - Kristin Kessler
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Uwe Thorsten Lux
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Angelika Anna Noegel
- Institute of Biochemistry I; Medical Faculty, University Hospital, University of Cologne, 50931 Cologne, Germany
| | - Jan Kremers
- Department of Ophthalmology, University Hospital Erlangen, 91054 Erlangen, Germany
| | | | - Andreas Gießl
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany.
- Department of Ophthalmology, University Hospital Erlangen, 91054 Erlangen, Germany.
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3
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Hoff S, Epting D, Falk N, Schroda S, Braun DA, Halbritter J, Hildebrandt F, Kramer-Zucker A, Bergmann C, Walz G, Lienkamp SS. The nucleoside-diphosphate kinase NME3 associates with nephronophthisis proteins and is required for ciliary function during renal development. J Biol Chem 2018; 293:15243-15255. [PMID: 30111592 PMCID: PMC6166740 DOI: 10.1074/jbc.ra117.000847] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 08/07/2018] [Indexed: 01/12/2023] Open
Abstract
Nephronophthisis (NPH) is an autosomal recessive renal disease leading to kidney failure in children and young adults. The protein products of the corresponding genes (NPHPs) are localized in primary cilia or their appendages. Only about 70% of affected individuals have a mutation in one of 100 renal ciliopathy genes, and no unifying pathogenic mechanism has been identified. Recently, some NPHPs, including NIMA-related kinase 8 (NEK8) and centrosomal protein 164 (CEP164), have been found to act in the DNA-damage response pathway and to contribute to genome stability. Here, we show that NME/NM23 nucleoside-diphosphate kinase 3 (NME3) that has recently been found to facilitate DNA-repair mechanisms binds to several NPHPs, including NEK8, CEP164, and ankyrin repeat and sterile α motif domain-containing 6 (ANKS6). Depletion of nme3 in zebrafish and Xenopus resulted in typical ciliopathy-associated phenotypes, such as renal malformations and left-right asymmetry defects. We further found that endogenous NME3 localizes to the basal body and that it associates also with centrosomal proteins, such as NEK6, which regulates cell cycle arrest after DNA damage. The ciliopathy-typical manifestations of NME3 depletion in two vertebrate in vivo models, the biochemical association of NME3 with validated NPHPs, and its localization to the basal body reveal a role for NME3 in ciliary function. We conclude that mutations in the NME3 gene may aggravate the ciliopathy phenotypes observed in humans.
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Affiliation(s)
- Sylvia Hoff
- From the Department of Medicine, Renal Division, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Daniel Epting
- From the Department of Medicine, Renal Division, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Nathalie Falk
- From the Department of Medicine, Renal Division, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Sophie Schroda
- From the Department of Medicine, Renal Division, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Daniela A Braun
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Jan Halbritter
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Friedhelm Hildebrandt
- Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Albrecht Kramer-Zucker
- From the Department of Medicine, Renal Division, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Carsten Bergmann
- From the Department of Medicine, Renal Division, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
- Center for Human Genetics, Bioscientia, 55218 Ingelheim, Germany, and
| | - Gerd Walz
- From the Department of Medicine, Renal Division, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
- Center for Biological Signaling Studies (BIOSS), 79104 Freiburg, Germany
| | - Soeren S Lienkamp
- From the Department of Medicine, Renal Division, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany,
- Center for Biological Signaling Studies (BIOSS), 79104 Freiburg, Germany
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Falk N, Kessler K, Schramm SF, Boldt K, Becirovic E, Michalakis S, Regus-Leidig H, Noegel AA, Ueffing M, Thiel CT, Roepman R, Brandstätter JH, Gießl A. Functional analyses of Pericentrin and Syne-2 interaction in ciliogenesis. J Cell Sci 2018; 131:jcs.218487. [PMID: 30054381 DOI: 10.1242/jcs.218487] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 07/12/2018] [Indexed: 01/31/2023] Open
Abstract
Pericentrin (Pcnt) is a multifunctional scaffold protein and mutations in the human PCNT gene are associated with several diseases, including ciliopathies. Pcnt plays a crucial role in ciliary development in olfactory receptor neurons, but its function in the photoreceptor-connecting cilium is unknown. We downregulated Pcnt in the retina ex vivo and in vivo via a virus-based RNA interference approach to study Pcnt function in photoreceptors. ShRNA-mediated knockdown of Pcnt impaired the development of the connecting cilium and the outer segment of photoreceptors, and caused a nuclear migration defect. In protein interaction screens, we found that the outer nuclear membrane protein Syne-2 (also known as Nesprin-2) is an interaction partner of Pcnt in photoreceptors. Syne-2 is important for positioning murine photoreceptor cell nuclei and for centrosomal migration during early ciliogenesis. CRISPR/Cas9-mediated knockout of Syne-2 in cell culture led to an overexpression and mislocalization of Pcnt and to ciliogenesis defects. Our findings suggest that the Pcnt-Syne-2 complex is important for ciliogenesis and outer segment formation during retinal development and plays a role in nuclear migration.
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Affiliation(s)
- Nathalie Falk
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Kristin Kessler
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Sinja-Fee Schramm
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Karsten Boldt
- Division of Experimental Ophthalmology and Medical Proteome Center, Center of Ophthalmology, University of Tübingen, 72074 Tübingen, Germany
| | - Elvir Becirovic
- Center for Integrated Protein Science Munich (CIPSM) at the Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Stylianos Michalakis
- Center for Integrated Protein Science Munich (CIPSM) at the Department of Pharmacy, Center for Drug Research, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Hanna Regus-Leidig
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Angelika A Noegel
- Institute of Biochemistry I, Medical Faculty, University Hospital, University of Cologne, 50931 Cologne, Germany
| | - Marius Ueffing
- Division of Experimental Ophthalmology and Medical Proteome Center, Center of Ophthalmology, University of Tübingen, 72074 Tübingen, Germany
| | - Christian T Thiel
- Institute of Human Genetics, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany
| | - Ronald Roepman
- Department of Human Genetics, Radboud University Medical Center, Nijmegen 6525 GA, The Netherlands
| | | | - Andreas Gießl
- Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
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Falk N, Kessler K, Glöckner J, Boldt K, Ueffing M, Roepman R, Thiel C, Brandstätter JH, Gießl A. Pericentrin interacts with KASH domain-containing protein Syne-2. Cilia 2015. [PMCID: PMC4519147 DOI: 10.1186/2046-2530-4-s1-p19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Kessler K, Falk N, Wunderlich I, Fröhlich M, Hauer N, Gießl A, Brandstätter JH, Sticht H, Ekici AB, Uebe S, Seemanová E, Reis A, Roepman R, Thiel C. Identification of mutations in DYNC2LI1, a member of the mammalian cytoplasmic dynein 2 complex, expands the clinical spectrum of Jeune/ATD ciliopathies. Cilia 2015. [PMCID: PMC4519171 DOI: 10.1186/2046-2530-4-s1-p59] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Gotthardt K, Lokaj M, Koerner C, Falk N, Gießl A, Wittinghofer A. A G-protein activation cascade from Arl13B to Arl3 and implications for ciliary targeting of lipidated proteins. eLife 2015; 4. [PMID: 26551564 PMCID: PMC4868535 DOI: 10.7554/elife.11859] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [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: 09/24/2015] [Accepted: 11/06/2015] [Indexed: 12/11/2022] Open
Abstract
Small G-proteins of the ADP-ribosylation-factor-like (Arl) subfamily have been shown to be crucial to ciliogenesis and cilia maintenance. Active Arl3 is involved in targeting and releasing lipidated cargo proteins from their carriers PDE6δ and UNC119a/b to the cilium. However, the guanine nucleotide exchange factor (GEF) which activates Arl3 is unknown. Here we show that the ciliary G-protein Arl13B mutated in Joubert syndrome is the GEF for Arl3, and its function is conserved in evolution. The GEF activity of Arl13B is mediated by the G-domain plus an additional C-terminal helix. The switch regions of Arl13B are involved in the interaction with Arl3. Overexpression of Arl13B in mammalian cell lines leads to an increased Arl3·GTP level, whereas Arl13B Joubert-Syndrome patient mutations impair GEF activity and thus Arl3 activation. We anticipate that through Arl13B's exclusive ciliary localization, Arl3 activation is spatially restricted and thereby an Arl3·GTP compartment generated where ciliary cargo is specifically released.
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Affiliation(s)
- Katja Gotthardt
- Structural Biology Group, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Mandy Lokaj
- Structural Biology Group, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Carolin Koerner
- Structural Biology Group, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Nathalie Falk
- Department of Biology, Animal Physiology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Andreas Gießl
- Department of Biology, Animal Physiology, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Alfred Wittinghofer
- Structural Biology Group, Max Planck Institute of Molecular Physiology, Dortmund, Germany
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Abstract
Cilia and flagella are highly conserved and important microtubule-based organelles that project from the surface of eukaryotic cells and act as antennae to sense extracellular signals. Moreover, cilia have emerged as key players in numerous physiological, developmental, and sensory processes such as hearing, olfaction, and photoreception. Genetic defects in ciliary proteins responsible for cilia formation, maintenance, or function underlie a wide array of human diseases like deafness, anosmia, and retinal degeneration in sensory systems. Impairment of more than one sensory organ results in numerous syndromic ciliary disorders like the autosomal recessive genetic diseases Bardet-Biedl and Usher syndrome. Here we describe the structure and distinct functional roles of cilia in sensory organs like the inner ear, the olfactory epithelium, and the retina of the mouse. The spectrum of ciliary function in fundamental cellular processes highlights the importance of elucidating ciliopathy-related proteins in order to find novel potential therapies.
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Affiliation(s)
- Nathalie Falk
- Department of Biology, Animal Physiology, University of Erlangen-Nuremberg, 91058 Erlangen, Germany.
| | - Marlene Lösl
- Department of Biology, Animal Physiology, University of Erlangen-Nuremberg, 91058 Erlangen, Germany.
| | - Nadja Schröder
- Department of Biology, Animal Physiology, University of Erlangen-Nuremberg, 91058 Erlangen, Germany.
| | - Andreas Gießl
- Department of Biology, Animal Physiology, University of Erlangen-Nuremberg, 91058 Erlangen, Germany.
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Zebrowski DC, Vergarajauregui S, Wu CC, Piatkowski T, Becker R, Leone M, Hirth S, Ricciardi F, Falk N, Giessl A, Just S, Braun T, Weidinger G, Engel FB. Developmental alterations in centrosome integrity contribute to the post-mitotic state of mammalian cardiomyocytes. eLife 2015; 4. [PMID: 26247711 PMCID: PMC4541494 DOI: 10.7554/elife.05563] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [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: 11/11/2014] [Accepted: 07/30/2015] [Indexed: 12/23/2022] Open
Abstract
Mammalian cardiomyocytes become post-mitotic shortly after birth. Understanding how this occurs is highly relevant to cardiac regenerative therapy. Yet, how cardiomyocytes achieve and maintain a post-mitotic state is unknown. Here, we show that cardiomyocyte centrosome integrity is lost shortly after birth. This is coupled with relocalization of various centrosome proteins to the nuclear envelope. Consequently, postnatal cardiomyocytes are unable to undergo ciliogenesis and the nuclear envelope adopts the function as cellular microtubule organizing center. Loss of centrosome integrity is associated with, and can promote, cardiomyocyte G0/G1 cell cycle arrest suggesting that centrosome disassembly is developmentally utilized to achieve the post-mitotic state in mammalian cardiomyocytes. Adult cardiomyocytes of zebrafish and newt, which are able to proliferate, maintain centrosome integrity. Collectively, our data provide a novel mechanism underlying the post-mitotic state of mammalian cardiomyocytes as well as a potential explanation for why zebrafish and newts, but not mammals, can regenerate their heart. DOI:http://dx.doi.org/10.7554/eLife.05563.001 Muscle cells in the heart contract in regular rhythms to pump blood around the body. In humans, rats and other mammals, the vast majority of heart muscle cells lose the ability to divide shortly after birth. Therefore, the heart is unable to replace cells that are lost over the life of the individual, for example, during a heart attack. If too many of these cells are lost, the heart will be unable to pump effectively, which can lead to heart failure. Currently, the only treatment option in humans with heart failure is to perform a heart transplant. Some animals, such as newts and zebrafish, are able to replace lost heart muscle cells throughout their lifetimes. Thus, these species are able to fully regenerate their hearts even after 20% has been removed. This suggests that it might be possible to manipulate human heart muscle cells to make them divide and regenerate the heart. Recent research has suggested that structures called centrosomes, known to be required to separate copies of the DNA during cell division, are used as a hub to integrate the initial signals that determine whether a cell should divide or not. Here, Zebrowski et al. studied the centrosomes of heart muscle cells in rats, newts and zebrafish. The experiments show that the centrosomes in rat heart muscle cells are dissembled shortly after birth. Centrosomes are made of several proteins and, in the rat cells, these proteins moved to the membrane that surrounded the nucleus. On the other hand, the centrosomes in the heart muscle cells of the adult newts and zebrafish remained intact. Further experiments found that that breaking apart the centrosomes of heart muscle cells taken from newborn rats stops these cells from dividing. Zebrowski et al.'s findings suggest that the loss of centrosomes after birth is a possible reason why the hearts of adult humans and other mammals are unable to regenerate after injury. In the future, these findings may aid the development of methods to regenerate human heart muscle and new treatments that may limit division of cancer cells. DOI:http://dx.doi.org/10.7554/eLife.05563.002
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Affiliation(s)
- David C Zebrowski
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Silvia Vergarajauregui
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Chi-Chung Wu
- Institute for Biochemistry and Molecular Biology, University of Ulm, Ulm, Germany
| | - Tanja Piatkowski
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Robert Becker
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Marina Leone
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Sofia Hirth
- Department of Medicine II, University of Ulm, Ulm, Germany
| | - Filomena Ricciardi
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Nathalie Falk
- Department of Biology, Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Andreas Giessl
- Department of Biology, Animal Physiology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Steffen Just
- Department of Medicine II, University of Ulm, Ulm, Germany
| | - Thomas Braun
- Department of Cardiac Development and Remodeling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Gilbert Weidinger
- Institute for Biochemistry and Molecular Biology, University of Ulm, Ulm, Germany
| | - Felix B Engel
- Experimental Renal and Cardiovascular Research, Department of Nephropathology, Institute of Pathology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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Goetz R, Cutler DL, Pollack D, Falk N, Birecree E, McFarland B, Keepers G, Walker D. A three-decade perspective on community and public psychiatry training in Oregon. Psychiatr Serv 1998; 49:1208-11. [PMID: 9735964 DOI: 10.1176/ps.49.9.1208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The public psychiatry training program at Oregon Health Sciences University, established in 1973, educates psychiatric residents to work in community mental health centers and state hospitals. The authors present a brief history of this program, which spans three decades, and describe recent developments in its operation, with special attention to financing, administrative structure, and educational elements. Several program graduates have chosen careers in public-sector work. The program is founded on the principle that just as dollars should follow patients in health care systems, so should residents in training follow patients. Administrative and fiscal arrangements must be flexible to support this mobility.
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Affiliation(s)
- R Goetz
- Department of Psychiatry at Oregon Health Sciences University, USA.
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Abstract
Derivatization of 4-hydroxyproline (Hyp) in collagen using trifluoroacetylation and methanol esterification produces two derivatives when analyzed by gas chromatography/mass spectrometry (GC/MS). The diacyl derivative N,O-bis(trifluoroacetyl)-4-hydroxy-L-proline methyl ester (N,O-TFA-Hyp) formed in this manner has a shorter retention time and different fragmentation pattern by GC/MS as compared to the slower eluting monoacetylated species N-trifluoroacetyl-4-hydroxy-L-proline methyl ester (N-TFA-Hyp). By selected ion monitoring of the appropriate ions of either N,O-TFA-Hyp (m/z 164, 278) or N-TFA-Hyp (m/z 164, 182) efficient quantitation of Hyp in collagen is possible within the broad range of 5-1000 ng with a lower limit of detection of 0.5 ng per injection. Measurement of 18O2 incorporation into collagen is possible by selected ion monitoring of the m/z 182 ion formed only from the monoacetylated derivative, N-TFA-Hyp, produced by methanol solvolysis of the N,O-TFA-Hyp derivative, as proposed herein.
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Affiliation(s)
- E E Tredget
- Department of Surgery, University of Alberta, Edmonton, Canada
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Fields AL, Falk N, Cheema-Dhadli S, Halperin ML. Accelerated loss of lean body mass in fasting rats due to activation of pyruvate dehydrogenase by dichloroacetate. Metabolism 1987; 36:621-4. [PMID: 3600275 DOI: 10.1016/0026-0495(87)90143-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In order to test the hypothesis that increased pyruvate dehydrogenase (PDH) activity during fasting will result in accelerated loss of lean body mass, we administered sodium dichloroacetate (DCA) intraperitoneally to eight rats during the last three days of a six-day fast, while fasting control rats were given normal saline. DCA treatment resulted in an increased proportion of PDH in the active form in liver (26.5 +/- 4.3% v 13.4 +/- 0.5%, P less than 0.01). During the three-day period of administration, DCA treated rats lost more weight than control animals (42 +/- 2 v 25 +/- 1 g, P less than 0.001) and excreted more nitrogen in the urine (18.1 +/- 1.0 v 6.8 +/- 0.6 mmol/d, P less than 0.001). Calculations from nitrogen balance data suggest that 85% of the increase in weight loss of DCA treated rats over that of control animals was attributable to loss of lean body mass. We conclude that increased flux of pyruvate through the PDH reaction in the DCA-treated animals resulted in increased protein catabolism.
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Falk N. [Rooming-in also in Vasa]. Katilolehti 1970; 75:520-1. [PMID: 5203914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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