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Plattner P, Wood E, Al Ayoubi L, Beliuskina O, Bissell ML, Blaum K, Campbell P, Cheal B, de Groote RP, Devlin CS, Eronen T, Filippin L, Garcia Ruiz RF, Ge Z, Geldhof S, Gins W, Godefroid M, Heylen H, Hukkanen M, Imgram P, Jaries A, Jokinen A, Kanellakopoulos A, Kankainen A, Kaufmann S, König K, Koszorús Á, Kujanpää S, Lechner S, Malbrunot-Ettenauer S, Müller P, Mathieson R, Moore I, Nörtershäuser W, Nesterenko D, Neugart R, Neyens G, Ortiz-Cortes A, Penttilä H, Pohjalainen I, Raggio A, Reponen M, Rinta-Antila S, Rodríguez LV, Romero J, Sánchez R, Sommer F, Stryjczyk M, Virtanen V, Xie L, Xu ZY, Yang XF, Yordanov DT. Nuclear Charge Radius of ^{26m}Al and Its Implication for V_{ud} in the Quark Mixing Matrix. Phys Rev Lett 2023; 131:222502. [PMID: 38101341 DOI: 10.1103/physrevlett.131.222502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 10/09/2023] [Indexed: 12/17/2023]
Abstract
Collinear laser spectroscopy was performed on the isomer of the aluminium isotope ^{26m}Al. The measured isotope shift to ^{27}Al in the 3s^{2}3p ^{2}P_{3/2}^{○}→3s^{2}4s ^{2}S_{1/2} atomic transition enabled the first experimental determination of the nuclear charge radius of ^{26m}Al, resulting in R_{c}=3.130(15) fm. This differs by 4.5 standard deviations from the extrapolated value used to calculate the isospin-symmetry breaking corrections in the superallowed β decay of ^{26m}Al. Its corrected Ft value, important for the estimation of V_{ud} in the Cabibbo-Kobayashi-Maskawa matrix, is thus shifted by 1 standard deviation to 3071.4(1.0) s.
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Affiliation(s)
- P Plattner
- ISOLDE, CERN Experimental Physics Department, Geneva 23, 1211 Genevè, Switzerland
- Universität Innsbruck, Innrain 52, 6020 Innsbruck, Austria
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - E Wood
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - L Al Ayoubi
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - O Beliuskina
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - M L Bissell
- ISOLDE, CERN Experimental Physics Department, Geneva 23, 1211 Genevè, Switzerland
- Department of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - K Blaum
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - P Campbell
- Department of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - B Cheal
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - R P de Groote
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - C S Devlin
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - T Eronen
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - L Filippin
- Spectroscopy, Quantum Chemistry and Atmospheric Remote Sensing (SQUARES), Université libre de Bruxelles, 1050 Brussels, Belgium
| | - R F Garcia Ruiz
- ISOLDE, CERN Experimental Physics Department, Geneva 23, 1211 Genevè, Switzerland
- Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, Massachusetts 02139, USA
| | - Z Ge
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - S Geldhof
- Instituut voor Kern- en Stralingsfysica, KU Leuven, 3001 Leuven, Belgium
| | - W Gins
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - M Godefroid
- Spectroscopy, Quantum Chemistry and Atmospheric Remote Sensing (SQUARES), Université libre de Bruxelles, 1050 Brussels, Belgium
| | - H Heylen
- ISOLDE, CERN Experimental Physics Department, Geneva 23, 1211 Genevè, Switzerland
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - M Hukkanen
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - P Imgram
- Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstraße 9, 64289 Darmstadt, Germany
| | - A Jaries
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - A Jokinen
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - A Kanellakopoulos
- Instituut voor Kern- en Stralingsfysica, KU Leuven, 3001 Leuven, Belgium
| | - A Kankainen
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - S Kaufmann
- Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstraße 9, 64289 Darmstadt, Germany
| | - K König
- Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstraße 9, 64289 Darmstadt, Germany
| | - Á Koszorús
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
- Instituut voor Kern- en Stralingsfysica, KU Leuven, 3001 Leuven, Belgium
| | - S Kujanpää
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - S Lechner
- ISOLDE, CERN Experimental Physics Department, Geneva 23, 1211 Genevè, Switzerland
| | - S Malbrunot-Ettenauer
- ISOLDE, CERN Experimental Physics Department, Geneva 23, 1211 Genevè, Switzerland
- TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3, Canada
| | - P Müller
- Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstraße 9, 64289 Darmstadt, Germany
| | - R Mathieson
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - I Moore
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - W Nörtershäuser
- Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstraße 9, 64289 Darmstadt, Germany
| | - D Nesterenko
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - R Neugart
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
- Institut für Kernchemie, Universität Mainz, Fritz-Straßmann-Weg 2, 55128 Mainz, Germany
| | - G Neyens
- ISOLDE, CERN Experimental Physics Department, Geneva 23, 1211 Genevè, Switzerland
- Instituut voor Kern- en Stralingsfysica, KU Leuven, 3001 Leuven, Belgium
| | - A Ortiz-Cortes
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - H Penttilä
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - I Pohjalainen
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - A Raggio
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - M Reponen
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - S Rinta-Antila
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - L V Rodríguez
- ISOLDE, CERN Experimental Physics Department, Geneva 23, 1211 Genevè, Switzerland
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
- IJCLab, CNRS/IN2P3, Université Paris-Saclay, 91400 Orsay, France
| | - J Romero
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - R Sánchez
- GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291 Darmstadt, Germany
| | - F Sommer
- Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstraße 9, 64289 Darmstadt, Germany
| | - M Stryjczyk
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - V Virtanen
- Department of Physics, University of Jyväskylä, P.O. Box 35 FI-40014, Jyväskylä, Finland
| | - L Xie
- Department of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Z Y Xu
- Instituut voor Kern- en Stralingsfysica, KU Leuven, 3001 Leuven, Belgium
| | - X F Yang
- Instituut voor Kern- en Stralingsfysica, KU Leuven, 3001 Leuven, Belgium
- School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, 209 Chengfu Road, 100871 Beijing, China
| | - D T Yordanov
- IJCLab, CNRS/IN2P3, Université Paris-Saclay, 91400 Orsay, France
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Chaker-Margot M, Werten S, Dunzendorfer-Matt T, Lechner S, Ruepp A, Scheffzek K, Maier T. Structural basis of activation of the tumor suppressor protein neurofibromin. Mol Cell 2022; 82:1288-1296.e5. [PMID: 35353986 DOI: 10.1016/j.molcel.2022.03.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [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: 11/15/2021] [Revised: 01/14/2022] [Accepted: 03/03/2022] [Indexed: 12/15/2022]
Abstract
Mutations in the NF1 gene cause the familial genetic disease neurofibromatosis type I, as well as predisposition to cancer. The NF1 gene product, neurofibromin, is a GTPase-activating protein and acts as a tumor suppressor by negatively regulating the small GTPase, Ras. However, structural insights into neurofibromin activation remain incompletely defined. Here, we provide cryoelectron microscopy (cryo-EM) structures that reveal an extended neurofibromin homodimer in two functional states: an auto-inhibited state with occluded Ras-binding site and an asymmetric open state with an exposed Ras-binding site. Mechanistically, the transition to the active conformation is stimulated by nucleotide binding, which releases a lock that tethers the catalytic domain to an extended helical repeat scaffold in the occluded state. Structure-guided mutational analysis supports functional relevance of allosteric control. Disease-causing mutations are mapped and primarily impact neurofibromin stability. Our findings suggest a role for nucleotides in neurofibromin regulation and may lead to therapeutic modulation of Ras signaling.
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Affiliation(s)
| | - Sebastiaan Werten
- Institute of Biological Chemistry, Biocenter, Medical University of Innsbruck, Innsbruck 6020, Austria
| | | | - Stefan Lechner
- Institute of Biological Chemistry, Biocenter, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Angela Ruepp
- Institute of Biological Chemistry, Biocenter, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Klaus Scheffzek
- Institute of Biological Chemistry, Biocenter, Medical University of Innsbruck, Innsbruck 6020, Austria.
| | - Timm Maier
- Biozentrum, University of Basel, 4056 Basel, Switzerland.
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Hatzmann FM, Ejaz A, Wiegers GJ, Mandl M, Brucker C, Lechner S, Rauchenwald T, Zwierzina M, Baumgarten S, Wagner S, Mattesich M, Waldegger P, Pierer G, Zwerschke W. Quiescence, Stemness and Adipogenic Differentiation Capacity in Human DLK1 -/CD34 +/CD24 + Adipose Stem/Progenitor Cells. Cells 2021; 10:cells10020214. [PMID: 33498986 PMCID: PMC7912596 DOI: 10.3390/cells10020214] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [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: 11/23/2020] [Revised: 01/13/2021] [Accepted: 01/16/2021] [Indexed: 12/26/2022] Open
Abstract
We explore the status of quiescence, stemness and adipogenic differentiation capacity in adipose stem/progenitor cells (ASCs) ex vivo, immediately after isolation from human subcutaneous white adipose tissue, by sorting the stromal vascular fraction into cell-surface DLK1+/CD34−, DLK1+/CD34dim and DLK1−/CD34+ cells. We demonstrate that DLK1−/CD34+ cells, the only population exhibiting proliferative and adipogenic capacity, express ex vivo the bonafide quiescence markers p21Cip1, p27Kip1 and p57Kip2 but neither proliferation markers nor the senescence marker p16Ink4a. The pluripotency markers NANOG, SOX2 and OCT4 are barely detectable in ex vivo ASCs while the somatic stemness factors, c-MYC and KLF4 and the early adipogenic factor C/EBPβ are highly expressed. Further sorting of ASCs into DLK1−/CD34+/CD24− and DLK1−/CD34+/CD24+ fractions shows that KLF4 and c-MYC are higher expressed in DLK1−/CD34+/CD24+ cells correlating with higher colony formation capacity and considerably lower adipogenic activity. Proliferation capacity is similar in both populations. Next, we show that ASCs routinely isolated by plastic-adherence are DLK1−/CD34+/CD24+. Intriguingly, CD24 knock-down in these cells reduces proliferation and adipogenesis. In conclusion, DLK1−/CD34+ ASCs in human sWAT exist in a quiescent state, express high levels of somatic stemness factors and the early adipogenic transcription factor C/EBPβ but senescence and pluripotency markers are barely detectable. Moreover, our data indicate that CD24 is necessary for adequate ASC proliferation and adipogenesis and that stemness is higher and adipogenic capacity lower in DLK1−/CD34+/CD24+ relative to DLK1−/CD34+/CD24− subpopulations.
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Affiliation(s)
- Florian M. Hatzmann
- Division of Cell Metabolism and Differentiation Research, Research Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, A-6020 Innsbruck, Austria; (F.M.H.); (A.E.); (M.M.); (C.B.); (S.L.); (S.B.); (S.W.); (P.W.)
- Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Asim Ejaz
- Division of Cell Metabolism and Differentiation Research, Research Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, A-6020 Innsbruck, Austria; (F.M.H.); (A.E.); (M.M.); (C.B.); (S.L.); (S.B.); (S.W.); (P.W.)
- Department of Plastic Surgery, University of Pittsburgh Medical Center, 3550 Terrace Street, 6B Scaife Hall, Pittsburgh, PA 15261, USA
| | - G. Jan Wiegers
- Division of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria;
| | - Markus Mandl
- Division of Cell Metabolism and Differentiation Research, Research Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, A-6020 Innsbruck, Austria; (F.M.H.); (A.E.); (M.M.); (C.B.); (S.L.); (S.B.); (S.W.); (P.W.)
- Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Camille Brucker
- Division of Cell Metabolism and Differentiation Research, Research Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, A-6020 Innsbruck, Austria; (F.M.H.); (A.E.); (M.M.); (C.B.); (S.L.); (S.B.); (S.W.); (P.W.)
- Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Stefan Lechner
- Division of Cell Metabolism and Differentiation Research, Research Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, A-6020 Innsbruck, Austria; (F.M.H.); (A.E.); (M.M.); (C.B.); (S.L.); (S.B.); (S.W.); (P.W.)
| | - Tina Rauchenwald
- Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck, Austria; (T.R.); (M.Z.); (M.M.); (G.P.)
| | - Marit Zwierzina
- Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck, Austria; (T.R.); (M.Z.); (M.M.); (G.P.)
| | - Saphira Baumgarten
- Division of Cell Metabolism and Differentiation Research, Research Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, A-6020 Innsbruck, Austria; (F.M.H.); (A.E.); (M.M.); (C.B.); (S.L.); (S.B.); (S.W.); (P.W.)
| | - Sonja Wagner
- Division of Cell Metabolism and Differentiation Research, Research Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, A-6020 Innsbruck, Austria; (F.M.H.); (A.E.); (M.M.); (C.B.); (S.L.); (S.B.); (S.W.); (P.W.)
| | - Monika Mattesich
- Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck, Austria; (T.R.); (M.Z.); (M.M.); (G.P.)
| | - Petra Waldegger
- Division of Cell Metabolism and Differentiation Research, Research Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, A-6020 Innsbruck, Austria; (F.M.H.); (A.E.); (M.M.); (C.B.); (S.L.); (S.B.); (S.W.); (P.W.)
- Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Gerhard Pierer
- Department of Plastic, Reconstructive and Aesthetic Surgery, Medical University of Innsbruck, Anichstraße 35, A-6020 Innsbruck, Austria; (T.R.); (M.Z.); (M.M.); (G.P.)
| | - Werner Zwerschke
- Division of Cell Metabolism and Differentiation Research, Research Institute for Biomedical Aging Research, University of Innsbruck, Rennweg 10, A-6020 Innsbruck, Austria; (F.M.H.); (A.E.); (M.M.); (C.B.); (S.L.); (S.B.); (S.W.); (P.W.)
- Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
- Correspondence: ; Tel.: +43-512-507508-32; Fax: +43-512-507508-99
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Gorges C, Rodríguez LV, Balabanski DL, Bissell ML, Blaum K, Cheal B, Garcia Ruiz RF, Georgiev G, Gins W, Heylen H, Kanellakopoulos A, Kaufmann S, Kowalska M, Lagaki V, Lechner S, Maaß B, Malbrunot-Ettenauer S, Nazarewicz W, Neugart R, Neyens G, Nörtershäuser W, Reinhard PG, Sailer S, Sánchez R, Schmidt S, Wehner L, Wraith C, Xie L, Xu ZY, Yang XF, Yordanov DT. Laser Spectroscopy of Neutron-Rich Tin Isotopes: A Discontinuity in Charge Radii across the N=82 Shell Closure. Phys Rev Lett 2019; 122:192502. [PMID: 31144969 DOI: 10.1103/physrevlett.122.192502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 03/22/2019] [Indexed: 06/09/2023]
Abstract
The change in mean-square nuclear charge radii δ⟨r^{2}⟩ along the even-A tin isotopic chain ^{108-134}Sn has been investigated by means of collinear laser spectroscopy at ISOLDE/CERN using the atomic transitions 5p^{2} ^{1}S_{0}→5p6 s^{1}P_{1} and 5p^{2} ^{3}P_{0}→5p6s ^{3}P_{1}. With the determination of the charge radius of ^{134}Sn and corrected values for some of the neutron-rich isotopes, the evolution of the charge radii across the N=82 shell closure is established. A clear kink at the doubly magic ^{132}Sn is revealed, similar to what has been observed at N=82 in other isotopic chains with larger proton numbers, and at the N=126 shell closure in doubly magic ^{208}Pb. While most standard nuclear density functional calculations struggle with a consistent explanation of these discontinuities, we demonstrate that a recently developed Fayans energy density functional provides a coherent description of the kinks at both doubly magic nuclei, ^{132}Sn and ^{208}Pb, without sacrificing the overall performance. A multiple correlation analysis leads to the conclusion that both kinks are related to pairing and surface effects.
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Affiliation(s)
- C Gorges
- Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | - L V Rodríguez
- Institut de Physique Nucléaire, CNRS-IN2P3, Université Paris-Sud, Université Paris-Saclay, 91406 Orsay, France
| | - D L Balabanski
- ELI-NP, Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering, 077125 Magurele, Romania
| | - M L Bissell
- School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - K Blaum
- Max-Planck-Institut für Kernphysik, D-69117 Heidelberg, Germany
| | - B Cheal
- Oliver Lodge Laboratory, Oxford Street, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - R F Garcia Ruiz
- School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
- Instituut voor Kern- en Stralingsfysica, KU Leuven, B-3001 Leuven, Belgium
- Experimental Physics Department, CERN, CH-1211 Geneva 23, Switzerland
| | - G Georgiev
- Institut de Physique Nucléaire, CNRS-IN2P3, Université Paris-Sud, Université Paris-Saclay, 91406 Orsay, France
| | - W Gins
- Instituut voor Kern- en Stralingsfysica, KU Leuven, B-3001 Leuven, Belgium
| | - H Heylen
- Max-Planck-Institut für Kernphysik, D-69117 Heidelberg, Germany
- Experimental Physics Department, CERN, CH-1211 Geneva 23, Switzerland
| | - A Kanellakopoulos
- Instituut voor Kern- en Stralingsfysica, KU Leuven, B-3001 Leuven, Belgium
| | - S Kaufmann
- Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | - M Kowalska
- Experimental Physics Department, CERN, CH-1211 Geneva 23, Switzerland
| | - V Lagaki
- Experimental Physics Department, CERN, CH-1211 Geneva 23, Switzerland
- Institut für Physik, Universität Greifswald, 17487 Greifswald, Germany
| | - S Lechner
- Experimental Physics Department, CERN, CH-1211 Geneva 23, Switzerland
- Technische Universität Wien, Karlsplatz 13, 1040 Wien, Austria
| | - B Maaß
- Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | | | - W Nazarewicz
- Department of Physics and Astronomy and FRIB Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
| | - R Neugart
- Max-Planck-Institut für Kernphysik, D-69117 Heidelberg, Germany
- Institut für Kernchemie, Universität Mainz, D-55128 Mainz, Germany
| | - G Neyens
- Instituut voor Kern- en Stralingsfysica, KU Leuven, B-3001 Leuven, Belgium
| | - W Nörtershäuser
- Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | - P-G Reinhard
- Institut für Theoretische Physik II, Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - S Sailer
- Technische Universität München, D-80333 Munich, Germany
| | - R Sánchez
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - S Schmidt
- Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
| | - L Wehner
- Institut für Kernchemie, Universität Mainz, D-55128 Mainz, Germany
| | - C Wraith
- Oliver Lodge Laboratory, Oxford Street, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - L Xie
- School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - Z Y Xu
- Instituut voor Kern- en Stralingsfysica, KU Leuven, B-3001 Leuven, Belgium
| | - X F Yang
- Instituut voor Kern- en Stralingsfysica, KU Leuven, B-3001 Leuven, Belgium
- School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, China
| | - D T Yordanov
- Institut de Physique Nucléaire, CNRS-IN2P3, Université Paris-Sud, Université Paris-Saclay, 91406 Orsay, France
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5
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Altamirano A, Naschberger A, Fürnrohr BG, Saldova R, Struwe WB, Jennings PM, Millán Martín S, Malic S, Plangger I, Lechner S, Pisano R, Peretti N, Linke B, Aguiar MM, Fresser F, Ritsch A, Lenac Rovis T, Goode C, Rudd PM, Scheffzek K, Rupp B, Dieplinger H. Expression, Purification, and Biochemical Characterization of Human Afamin. J Proteome Res 2018; 17:1269-1277. [PMID: 29441788 DOI: 10.1021/acs.jproteome.7b00867] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Afamin is an 87 kDa glycoprotein with five predicted N-glycosylation sites. Afamin's glycan abundance contributes to conformational and chemical inhomogeneity presenting great challenges for molecular structure determination. For the purpose of studying the structure of afamin, various forms of recombinantly expressed human afamin (rhAFM) with different glycosylation patterns were thus created. Wild-type rhAFM and various hypoglycosylated forms were expressed in CHO, CHO-Lec1, and HEK293T cells. Fully nonglycosylated rhAFM was obtained by transfection of point-mutated cDNA to delete all N-glycosylation sites of afamin. Wild-type and hypo/nonglycosylated rhAFM were purified from cell culture supernatants by immobilized metal ion affinity and size exclusion chromatography. Glycan analysis of purified proteins demonstrated differences in micro- and macro-heterogeneity of glycosylation enabling the comparison between hypoglycosylated, wild-type rhAFM, and native plasma afamin. Because antibody fragments can work as artificial chaperones by stabilizing the structure of proteins and consequently enhance the chance for successful crystallization, we incubated a Fab fragment of the monoclonal anti-afamin antibody N14 with human afamin and obtained a stoichiometric complex. Subsequent results showed sufficient expression of various partially or nonglycosylated forms of rhAFM in HEK293T and CHO cells and revealed that glycosylation is not necessary for expression and secretion.
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Affiliation(s)
| | | | | | - Radka Saldova
- NIBRT GlycoScience Group, National Institute for Bioprocessing Research & Training , Dublin, Ireland
| | - Weston B Struwe
- NIBRT GlycoScience Group, National Institute for Bioprocessing Research & Training , Dublin, Ireland
| | - Patrick M Jennings
- NIBRT GlycoScience Group, National Institute for Bioprocessing Research & Training , Dublin, Ireland
| | - Silvia Millán Martín
- NIBRT GlycoScience Group, National Institute for Bioprocessing Research & Training , Dublin, Ireland
| | - Suzana Malic
- Center for Proteomics, Faculty of Medicine, University of Rijeka , 51000 Rijeka, Croatia
| | | | | | | | | | | | | | | | | | - Tihana Lenac Rovis
- Center for Proteomics, Faculty of Medicine, University of Rijeka , 51000 Rijeka, Croatia
| | | | - Pauline M Rudd
- NIBRT GlycoScience Group, National Institute for Bioprocessing Research & Training , Dublin, Ireland
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Naschberger A, Orry A, Lechner S, Bowler MW, Nurizzo D, Novokmet M, Keller MA, Oemer G, Seppi D, Haslbeck M, Pansi K, Dieplinger H, Rupp B. Structural Evidence for a Role of the Multi-functional Human Glycoprotein Afamin in Wnt Transport. Structure 2017; 25:1907-1915.e5. [PMID: 29153507 DOI: 10.1016/j.str.2017.10.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 09/14/2017] [Accepted: 10/23/2017] [Indexed: 11/19/2022]
Abstract
Afamin, a human plasma glycoprotein and putative transporter of hydrophobic molecules, has been shown to act as extracellular chaperone for poorly soluble, acylated Wnt proteins, forming a stable, soluble complex with functioning Wnt proteins. The 2.1-Å crystal structure of glycosylated human afamin reveals an almost exclusively hydrophobic binding cleft capable of harboring large hydrophobic moieties. Lipid analysis confirms the presence of lipids, and density in the primary binding pocket of afamin was modeled as palmitoleic acid, presenting the native O-acylation on serine 209 in human Wnt3a. The modeled complex between the experimental afamin structure and a Wnt3a homology model based on the XWnt8-Fz8-CRD fragment complex crystal structure is compelling, with favorable interactions comparable with the crystal structure complex. Afamin readily accommodates the conserved palmitoylated serine 209 of Wnt3a, providing a structural basis how afamin solubilizes hydrophobic and poorly soluble Wnt proteins.
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Affiliation(s)
- Andreas Naschberger
- Division of Genetic Epidemiology, Medical University of Innsbruck, Schöpfstraße 41, 6020 Innsbruck, Austria; Division of Biological Chemistry, Medical University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Andrew Orry
- MolSoft LLC, 11199 Sorrento Valley Road, San Diego, CA 92121, USA
| | - Stefan Lechner
- Division of Genetic Epidemiology, Medical University of Innsbruck, Schöpfstraße 41, 6020 Innsbruck, Austria
| | - Matthew W Bowler
- European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue des Martyrs, 38043 Grenoble, France
| | - Didier Nurizzo
- Structural Biology Group, ESRF, 71 Avenue des Martyrs, 38000 Grenoble, France
| | - Mislav Novokmet
- Genos, Glycoscience Laboratory, Hondlova 2/11, 10000 Zagreb, Croatia
| | - Markus A Keller
- Division of Human Genetics, Medical University of Innsbruck, Peter-Mayr-Straße 1, 6020 Innsbruck, Austria
| | - Gregor Oemer
- Genos, Glycoscience Laboratory, Hondlova 2/11, 10000 Zagreb, Croatia
| | - Daniele Seppi
- Division of Biological Chemistry, Medical University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Martin Haslbeck
- Department of Chemistry, Technical University of Munich, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Kathrin Pansi
- Division of Biological Chemistry, Medical University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Hans Dieplinger
- Division of Genetic Epidemiology, Medical University of Innsbruck, Schöpfstraße 41, 6020 Innsbruck, Austria
| | - Bernhard Rupp
- Division of Genetic Epidemiology, Medical University of Innsbruck, Schöpfstraße 41, 6020 Innsbruck, Austria; k.-k. Hofkristallamt, San Diego, CA 92084, USA.
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Filipek PA, de Araujo MEG, Vogel GF, De Smet CH, Eberharter D, Rebsamen M, Rudashevskaya EL, Kremser L, Yordanov T, Tschaikner P, Fürnrohr BG, Lechner S, Dunzendorfer-Matt T, Scheffzek K, Bennett KL, Superti-Furga G, Lindner HH, Stasyk T, Huber LA. LAMTOR/Ragulator is a negative regulator of Arl8b- and BORC-dependent late endosomal positioning. J Cell Biol 2017; 216:4199-4215. [PMID: 28993467 PMCID: PMC5716276 DOI: 10.1083/jcb.201703061] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 07/28/2017] [Accepted: 09/11/2017] [Indexed: 12/18/2022] Open
Abstract
Signaling from lysosomes controls cellular clearance and energy metabolism. Lysosomal malfunction has been implicated in several pathologies, including neurodegeneration, cancer, infection, immunodeficiency, and obesity. Interestingly, many functions are dependent on the organelle position. Lysosomal motility requires the integration of extracellular and intracellular signals that converge on a competition between motor proteins that ultimately control lysosomal movement on microtubules. Here, we identify a novel upstream control mechanism of Arl8b-dependent lysosomal movement toward the periphery of the cell. We show that the C-terminal domain of lyspersin, a subunit of BLOC-1-related complex (BORC), is essential and sufficient for BORC-dependent recruitment of Arl8b to lysosomes. In addition, we establish lyspersin as the linker between BORC and late endosomal/lysosomal adaptor and mitogen activated protein kinase and mechanistic target of rapamycin activator (LAMTOR) complexes and show that epidermal growth factor stimulation decreases LAMTOR/BORC association, thereby promoting BORC- and Arl8b-dependent lysosomal centrifugal transport.
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Affiliation(s)
- Przemyslaw A Filipek
- Division of Cell Biology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Mariana E G de Araujo
- Division of Cell Biology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Georg F Vogel
- Division of Cell Biology, Biocenter, Innsbruck Medical University, Innsbruck, Austria.,Department of Pediatrics I, Innsbruck Medical University, Innsbruck, Austria
| | - Cedric H De Smet
- Division of Cell Biology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Daniela Eberharter
- Division of Cell Biology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Manuele Rebsamen
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Elena L Rudashevskaya
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Dortmund, Germany
| | - Leopold Kremser
- Division of Clinical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Teodor Yordanov
- Division of Cell Biology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Philipp Tschaikner
- Institute for Molecular Biology, Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
| | - Barbara G Fürnrohr
- Division of Biological Chemistry, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Stefan Lechner
- Division of Biological Chemistry, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | | | - Klaus Scheffzek
- Division of Biological Chemistry, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Keiryn L Bennett
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Giulio Superti-Furga
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Herbert H Lindner
- Division of Clinical Biochemistry, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Taras Stasyk
- Division of Cell Biology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Lukas A Huber
- Division of Cell Biology, Biocenter, Innsbruck Medical University, Innsbruck, Austria
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de Araujo MEG, Naschberger A, Fürnrohr BG, Stasyk T, Dunzendorfer-Matt T, Lechner S, Welti S, Kremser L, Shivalingaiah G, Offterdinger M, Lindner HH, Huber LA, Scheffzek K. Crystal structure of the human lysosomal mTORC1 scaffold complex and its impact on signaling. Science 2017; 358:377-381. [PMID: 28935770 DOI: 10.1126/science.aao1583] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 09/11/2017] [Indexed: 12/15/2022]
Abstract
The LAMTOR [late endosomal and lysosomal adaptor and MAPK (mitogen-activated protein kinase) and mTOR (mechanistic target of rapamycin) activator] complex, also known as "Ragulator," controls the activity of mTOR complex 1 (mTORC1) on the lysosome. The crystal structure of LAMTOR consists of two roadblock/LC7 domain-folded heterodimers wrapped and apparently held together by LAMTOR1, which assembles the complex on lysosomes. In addition, the Rag guanosine triphosphatases (GTPases) associated with the pentamer through their carboxyl-terminal domains, predefining the orientation for interaction with mTORC1. In vitro reconstitution and experiments with site-directed mutagenesis defined the physiological importance of LAMTOR1 in assembling the remaining components to ensure fidelity of mTORC1 signaling. Functional data validated the effect of two short LAMTOR1 amino acid regions in recruitment and stabilization of the Rag GTPases.
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Affiliation(s)
- Mariana E G de Araujo
- Division of Cell Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Andreas Naschberger
- Division of Biological Chemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Barbara G Fürnrohr
- Division of Biological Chemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Taras Stasyk
- Division of Cell Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | | | - Stefan Lechner
- Division of Biological Chemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Stefan Welti
- Division of Biological Chemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Leopold Kremser
- Division of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Giridhar Shivalingaiah
- Division of Biological Chemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Martin Offterdinger
- Division of Neurobiochemistry-Biooptics, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Herbert H Lindner
- Division of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Lukas A Huber
- Division of Cell Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria. .,Austrian Drug Screening Institute, 6020 Innsbruck, Austria
| | - Klaus Scheffzek
- Division of Biological Chemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria.
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9
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Andre-Gregoire G, Barrera-Chimal J, Nguyen Dinh Cat A, Lechner S, Cau J, Prince S, Loirand G, Sauzeau V, Hauet T, Jaisser F. Benefit of Mineralocorticoid Receptor antagonism in ischemia-reperfusion induced acute kidney injury: role of vascular smooth muscle Rac1. Archives of Cardiovascular Diseases Supplements 2017. [DOI: 10.1016/s1878-6480(17)30457-3] [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: 11/17/2022]
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10
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Moshourab R, Frenzel H, Lechner S, Haseleu J, Bégay V, Omerbašić D, Lewin GR. Measurement of Vibration Detection Threshold and Tactile Spatial Acuity in Human Subjects. J Vis Exp 2016. [PMID: 27684317 DOI: 10.3791/52966] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Tests that allow the precise determination of psychophysical thresholds for vibration and grating orientation provide valuable information about mechanosensory function that are relevant for clinical diagnosis as well as for basic research. Here, we describe two psychophysical tests designed to determine the vibration detection threshold (automated system) and tactile spatial acuity (handheld device). Both procedures implement a two-interval forced-choice and a transformed-rule up and down experimental paradigm. These tests have been used to obtain mechanosensory profiles for individuals from distinct human cohorts such as twins or people with sensorineural deafness.
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Affiliation(s)
- Rabih Moshourab
- Department of Anesthesiology and Intensive Care Medicine, Charite Universitätsmedzin, Campus Virchow Klinikum und Campus Charite Mitte; Department of Neuroscience, Molecular Physiology of Somatic Sensation, Max Delbrück Center for Molecular Medicine;
| | - Henning Frenzel
- Department of Neuroscience, Molecular Physiology of Somatic Sensation, Max Delbrück Center for Molecular Medicine
| | | | - Julia Haseleu
- Department of Neuroscience, Molecular Physiology of Somatic Sensation, Max Delbrück Center for Molecular Medicine
| | - Valérie Bégay
- Department of Neuroscience, Molecular Physiology of Somatic Sensation, Max Delbrück Center for Molecular Medicine
| | - Damir Omerbašić
- Department of Neuroscience, Molecular Physiology of Somatic Sensation, Max Delbrück Center for Molecular Medicine
| | - Gary R Lewin
- Department of Neuroscience, Molecular Physiology of Somatic Sensation, Max Delbrück Center for Molecular Medicine
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11
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Biewer M, Lechner S, Hasselmann M. Similar but not the same: insights into the evolutionary history of paralogous sex-determining genes of the dwarf honey bee Apis florea. Heredity (Edinb) 2015; 116:12-22. [PMID: 26153222 DOI: 10.1038/hdy.2015.60] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 05/01/2015] [Accepted: 05/06/2015] [Indexed: 01/07/2023] Open
Abstract
Studying the fate of duplicated genes provides informative insight into the evolutionary plasticity of biological pathways to which they belong. In the paralogous sex-determining genes complementary sex determiner (csd) and feminizer (fem) of honey bee species (genus Apis), only heterozygous csd initiates female development. Here, the full-length coding sequences of the genes csd and fem of the phylogenetically basal dwarf honey bee Apis florea are characterized. Compared with other Apis species, remarkable evolutionary changes in the formation and localization of a protein-interacting (coiled-coil) motif and in the amino acids coding for the csd characteristic hypervariable region (HVR) are observed. Furthermore, functionally different csd alleles were isolated as genomic fragments from a random population sample. In the predicted potential specifying domain (PSD), a high ratio of πN/πS=1.6 indicated positive selection, whereas signs of balancing selection, commonly found in other Apis species, are missing. Low nucleotide diversity on synonymous and genome-wide, non-coding sites as well as site frequency analyses indicated a strong impact of genetic drift in A. florea, likely linked to its biology. Along the evolutionary trajectory of ~30 million years of csd evolution, episodic diversifying selection seems to have acted differently among distinct Apis branches. Consistently low amino-acid differences within the PSD among pairs of functional heterozygous csd alleles indicate that the HVR is the most important region for determining allele specificity. We propose that in the early history of the lineage-specific fem duplication giving rise to csd in Apis, A. florea csd stands as a remarkable example for the plasticity of initial sex-determining signals.
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Affiliation(s)
- M Biewer
- Department of Livestock Population Genomics, Institute of Animal Science, University of Hohenheim, Stuttgart, Germany
| | - S Lechner
- CeGaT GmbH - Center for Genomics and Transcriptomics, Tübingen, Germany
| | - M Hasselmann
- Department of Livestock Population Genomics, Institute of Animal Science, University of Hohenheim, Stuttgart, Germany
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12
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13
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Mitterberger MC, Lechner S, Mattesich M, Zwerschke W. Adipogenic differentiation is impaired in replicative senescent human subcutaneous adipose-derived stromal/progenitor cells. J Gerontol A Biol Sci Med Sci 2013; 69:13-24. [PMID: 23657974 DOI: 10.1093/gerona/glt043] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
We demonstrate that adipose-derived stromal/progenitor cells isolated from abdominal subcutaneous fat pads of adult donors successively enter replicative senescence after long-term cultivation. This is characterized by enlarged cell size, flattened morphology, and upregulated senescence-associated β-galactosidase activity. Moreover, the senescence- associated cyclin-dependent kinase inhibitors p16(Ink4A) and p21(Cip1) were induced correlating with activation of the G1/S cell cycle inhibitor retinoblastoma protein and terminal proliferation arrest. The number of cells in the adipose-derived stromal/progenitor cell population with high adipogenic capacity declined inversely with the increase of senescent cells. Adipogenic hormone cocktail induced expression of the adipogenic key regulators peroxisome proliferator-activated receptor-γ2 and CCAAT/enhancer-binding protein α was significantly reduced in senescent adipose-derived stromal/ progenitor cells. Furthermore, the expression of the adipogenic differentiation genes fatty acid binding protein-4, adiponectin, and leptin and the formation of fat droplets were impaired. We conclude cellular senescence contributes to dysfunctions in adipose-derived stromal/progenitor cell replication, adipogenesis, triglyceride storage, and adipokine secretion.
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14
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Merzsch M, Lechner S, Krautz HJ. Heat-transfer from single horizontal tubes in fluidized beds: Influence of tube diameter, moisture and diameter-definition by Geldart C fines content. POWDER TECHNOL 2013. [DOI: 10.1016/j.powtec.2012.12.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [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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15
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16
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Kauhausen A, Schellert N, Köhler AK, Zhang E, Lechner S, Wachtlin J. Erfahrungen zur Wirkung und Wirkdauer des implantierbaren Dexamethasonspellets Ozurdex am vitrektomierten Auge. Klin Monbl Augenheilkd 2012. [DOI: 10.1055/s-0032-1331558] [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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17
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Schellert N, Lechner S, Zhang E, Wachtlin J. Besondere Merkmale von Patienten mit Pseudoendophthalmitis nach intravitrealer Triamcinolon- Injektion. Klin Monbl Augenheilkd 2012. [DOI: 10.1055/s-0032-1331514] [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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Mitterberger MC, Lechner S, Mattesich M, Kaiser A, Probst D, Wenger N, Pierer G, Zwerschke W. DLK1(PREF1) is a negative regulator of adipogenesis in CD105⁺/CD90⁺/CD34⁺/CD31⁻/FABP4⁻ adipose-derived stromal cells from subcutaneous abdominal fat pats of adult women. Stem Cell Res 2012; 9:35-48. [PMID: 22640926 DOI: 10.1016/j.scr.2012.04.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 04/04/2012] [Accepted: 04/06/2012] [Indexed: 12/20/2022] Open
Abstract
The main physiological function of adipose-derived stromal/progenitor cells (ASC) is to differentiate into adipocytes. ASC are most likely localized at perivascular sites in adipose tissues and retain the capacity to differentiate into multiple cell types. Although cell surface markers for ASC have been described, there is no complete consensus on the antigen expression pattern that will precisely define these cells. DLK1(PREF1) is an established marker for mouse adipocyte progenitors which inhibits adipogenesis. This suggests that DLK1(PREF1) could be a useful marker to characterize human ASC. The DLK1(PREF1) status of human ASC is however unknown. In the present study we isolated ASC from the heterogeneous stromal vascular fraction of subcutaneous abdominal fat pats of adult women. These cells were selected by their plastic adherence and expanded to passage 5. The ASC were characterized as relatively homogenous cell population with the capacity to differentiate in vitro into adipocytes, chondrocytes, and osteoblasts and the immunophenotype CD105⁺/CD90⁺/CD34⁺/CD31⁻/FABP4⁻. The ASC were positive for DLK1(PREF1) which was well expressed in proliferating and density arrested cells but downregulated in the course of adipogenic differentiation. To investigate whether DLK1(PREF1) plays a role in the regulation of adipogenesis in these cells RNAi-mediated knockdown experiments were conducted. Knockdown of DLK1(PREF1) in differentiating ASC resulted in a significant increase of the expression of the adipogenic key regulator PPARγ2 and of the terminal adipogenic differentiation marker FABP4. We conclude that DLK1(PREF1) is well expressed in human ASC and acts as a negative regulator of adipogenesis. Moreover, DLK1(PREF1) could be a functional marker contributing to the characterization of human ASC.
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Affiliation(s)
- Maria C Mitterberger
- Department of Cell Metabolism and Differentiation Research, Institute for Biomedical Aging Research of the Austrian Academy of Sciences, Rennweg 10, A-6020 Innsbruck, Austria
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Lechner S, Köhler A, Bezatis A, Spital G, Maier M, Horn M, Clemens C, Lehmann F, Höhn F, Meyer C, Wachtlin J. Anatomische und funktionelle Ergebnisse der klinischen Anwendung von Ozurdex® bei Venenast- (VAV) und Zentralvenenverschlüssen (ZVV) aus 8 Zentren in Deutschland. Klin Monbl Augenheilkd 2011. [DOI: 10.1055/s-0031-1297328] [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: 10/15/2022]
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20
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Morandell D, Kaiser A, Herold S, Rostek U, Lechner S, Mitterberger MC, Jansen-Dürr P, Eilers M, Zwerschke W. The human papillomavirus type 16 E7 oncoprotein targets Myc-interacting zinc-finger protein-1. Virology 2011; 422:242-53. [PMID: 22099967 PMCID: PMC3268862 DOI: 10.1016/j.virol.2011.10.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Revised: 06/13/2011] [Accepted: 10/28/2011] [Indexed: 12/29/2022]
Abstract
We demonstrate that HPV-16 E7 forms a complex with Miz-1. UV-induced expression of the CDK-inhibitor p21Cip1 and subsequent cell cycle arrest depends upon endogenous Miz-1 in HPV-negative C33A cervical cancer cells containing mutated p53. Transient expression of E7 in C33A inhibits UV-induced expression of p21Cip1 and overcomes Miz-1-induced G1-phase arrest. The C-terminal E7Δ79LEDLL83-mutant with reduced Miz-1-binding capacity was impaired in its capability to repress p21Cip1 expression; whereas the pRB-binding-deficient E7C24G-mutant inhibited p21Cip1 expression similar to wild-type E7. Using ChIP, we demonstrate that endogenous E7 is bound to the endogenous p21Cip1 core-promoter in CaSki cells and RNAi-mediated knock down of Miz-1 abrogates E7-binding to the p21Cip1 promoter. Co-expression of E7 with Miz-1 inhibited Miz-1-induced p21Cip1 expression from the minimal-promoter via Miz-1 DNA-binding sites. Co-expression of E7Δ79LEDLL83 did not inhibit Miz-1-induced p21Cip1 expression. E7C24G retained E7-wild-type capability to inhibit Miz-1-dependent transactivation. These findings suggest that HPV-16 E7 can repress Miz-1-induced p21Cip1 gene expression.
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Affiliation(s)
- Dieter Morandell
- Cell Metabolism and Differentiation Research Group, Institute for Biomedical Aging Research of the Austrian Academy of Sciences, Innsbruck, Austria
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21
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Erdmann S, Lechner S, Wachtlin J. IOL Explantation – ein zunehmendes Problem? – Operative Strategien zur sekundären IOL Implantation. Klin Monbl Augenheilkd 2010. [DOI: 10.1055/s-0030-1269990] [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: 10/18/2022]
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Lechner S, Schellert N, Wachtlin J. Erste Kurzzeiterfahrungen mit dem Langzeit-Dexamethasonpräparat (Ozurdex®) bei der Therapie von Maculaödemen im Off label use aufgrund anderer Erkrankungen als venöse Verschlüsse. Klin Monbl Augenheilkd 2010. [DOI: 10.1055/s-0030-1270056] [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: 10/18/2022]
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23
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Dreier K, Scheiden R, Lener B, Ehehalt D, Pircher H, Müller-Holzner E, Rostek U, Kaiser A, Fiedler M, Ressler S, Lechner S, Widschwendter A, Even J, Capesius C, Jansen-Dürr P, Zwerschke W. Subcellular localization of the human papillomavirus 16 E7 oncoprotein in CaSki cells and its detection in cervical adenocarcinoma and adenocarcinoma in situ. Virology 2010; 409:54-68. [PMID: 20970819 PMCID: PMC3003157 DOI: 10.1016/j.virol.2010.09.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2010] [Revised: 06/17/2010] [Accepted: 09/22/2010] [Indexed: 11/18/2022]
Abstract
E7 is the major oncoprotein of high-risk human papillomaviruses (HPV) which causes cervical cancer. To date E7 oncoproteins have not been investigated in cervical adenocarcinoma. In this study we generated a rabbit monoclonal anti-HPV-16 E7 antibody, RabMab42-3, which recognizes a conformational epitope in the E7 carboxy-terminal zinc-finger resulting in a strong increase in the sensitivity for the detection of cell-associated HPV-16 E7 protein relative to conventional polyclonal anti-HPV-16 E7 antibodies. Using RabMab42-3, we show that the subcellular localization of endogenous HPV-16 E7 oncoprotein varies during the cell cycle in cervical cancer cells. Moreover, we demonstrate for the first time that the HPV-16 E7 oncoprotein is abundantly expressed in cervical adenocarcinoma in situ and adenocarcinoma, suggesting an important role of HPV-16 E7 for the development of these tumors. Our findings suggest that the HPV-16 E7 oncoprotein could be a useful marker for the detection of cervical adenocarcinoma and their precursors.
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Affiliation(s)
- Kerstin Dreier
- Institute for Biomedical Aging Research of the Austrian Academy of Sciences, Innsbruck, Austria
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24
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Mitterberger MC, Mattesich M, Klaver E, Lechner S, Engelhardt T, Larcher L, Pierer G, Piza-Katzer H, Zwerschke W. Adipokine profile and insulin sensitivity in formerly obese women subjected to bariatric surgery or diet-induced long-term caloric restriction. J Gerontol A Biol Sci Med Sci 2010; 65:915-23. [PMID: 20576650 DOI: 10.1093/gerona/glq107] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
To better understand the contribution of the fat mass to the effects of long-term caloric restriction in humans, we compared adipokine profile and insulin sensitivity in long-term calorically restricted formerly obese women (CRW) subjected to different interventions, bariatric surgery, or reducing diet, with age- and BMI-matched obese (OW) and normal-weight women (NW) eating ad libitum. Our key findings are that despite a considerably stronger weight loss induced by bariatric surgery, both long-term caloric restriction interventions improved insulin sensitivity to the same degree and led to significantly lower retinol-binding protein-4 and interleukin-6 serum levels than in OW, suggesting that lowering of these two adipokines contributes to the improved insulin sensitivity. Moreover, serum leptin was considerably lower in CRW than in OW as well as in NW, suggesting that CRW develop hypoleptinemia.
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Affiliation(s)
- Maria C Mitterberger
- Cell Metabolism and Differentiation Research Group, Institute for Biomedical Aging Research, Austrian Academy of Sciences, Rennweg 10, 6020 Innsbruck, Austria
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25
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Lohninger A, Radler U, Jinniate S, Lohninger S, Karlic H, Lechner S, Mascher D, Tammaa A, Salzer H. Relationship between carnitine, fatty acids and insulin resistance. ACTA ACUST UNITED AC 2010; 49:230-5. [PMID: 20530934 DOI: 10.1159/000301075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Increased plasma free fatty acid (FFA) levels are a feature of insulin resistance and type 2 diabetes. The aim of the present study was to assess the effect of L-carnitine supplementation on plasma lipids and the expression of enzymes in peripheral mononucleated cells (PMNC) involved in the regulation of fatty acid and glucose oxidation. L-Carnitine supplementation of 2 g/day resulted in a significant decrease in plasma FFA and in a less pronounced diminution of the plasma triacylglycerols. In addition, a concomitant increase in the relative mRNA abundances of carnitine acyltransferases (5- to 10-fold) and of the carnitine carrier OCTN2 (12-fold) in PMNC of pregnant women was found. The results of the present study provide evidence that L-carnitine supplementation in pregnancy (2 g/day) avoids a striking increase in plasma FFA, which are thought to be the main cause of insulin resistance and consequently gestational diabetes mellitus.
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Affiliation(s)
- Alfred Lohninger
- Center for Physiology and Pathophysiology, Institute of Medical Chemistry, Medical University of Vienna, Währingerstrasse 10, Vienna, Austria.
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26
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Abstract
In this case study, we present two Holocaust survivors who appeared to have adapted well post-trauma, but developed severe PTSD symptomatology following the onset of neurologic illness in later life. These individuals were referred fro neuropsychological evaluations by their treating neurologists to assess their levels of cognitive functioning. We present the neuropsychological findings, and discuss possible mechanisms for emergence of PTSD symptoms. These case studies demonstrate the need for systematic research to further investigate the potential relationship between aging, degenerative disease, and PTSD symptoms in elderly trauma survivors.
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Affiliation(s)
- A B Grossman
- Department of Neurology, University of Miami School of Medicine, Miami, FL 33136, USA
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27
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Lechner S, Wachtlin J. Therapie des Makulaödems bei retinalen Venenverschlüssen – Abwarten? Laser? Intravitreale Injektion? Kombination? Klin Monbl Augenheilkd 2009. [DOI: 10.1055/s-0029-1243710] [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: 10/20/2022]
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28
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Schellert N, Galanski M, Wehner A, Zhang EP, Lechner S, Wachtlin J. Funktionelle und morphologische Ergebnisse nach 23 Gauge Pars-plana-Vitrektomie und simultaner Phakoemulisfikation mit HKL bei Makulaforamen und Makulapucker. Klin Monbl Augenheilkd 2009. [DOI: 10.1055/s-0029-1243701] [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: 10/20/2022]
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29
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Erdmann S, Wehner A, Zhang EP, Lechner S, Wachtlin J. Therapie ausgedehnter subretinaler Blutungen bei AMD mittels Pars-plana-Vitrektomie und subretinalem r-TPA + SF6-Gas. Klin Monbl Augenheilkd 2009. [DOI: 10.1055/s-0029-1243704] [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: 10/20/2022]
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30
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Spoden GA, Rostek U, Lechner S, Mitterberger M, Mazurek S, Zwerschke W. Pyruvate kinase isoenzyme M2 is a glycolytic sensor differentially regulating cell proliferation, cell size and apoptotic cell death dependent on glucose supply. Exp Cell Res 2009; 315:2765-74. [PMID: 19563799 DOI: 10.1016/j.yexcr.2009.06.024] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 05/29/2009] [Accepted: 06/22/2009] [Indexed: 11/19/2022]
Abstract
The glycolytic key regulator pyruvate kinase M2 (M2-PK or PKM2) can switch between a highly active tetrameric and an inactive dimeric form. The transition between the two conformations regulates the glycolytic flux in tumor cells. We developed specific M2-PK-binding peptide aptamers which inhibit M2-PK, but not the 96% homologous M1-PK isoenzyme. In this study we demonstrate that, at normal blood glucose concentrations, peptide aptamer-mediated inhibition of M2-PK induces a significant decrease of the population doubling (PDL rate) and cell proliferation rate as well as an increase in cell size, whereas under glucose restriction an increase in PDL and cell proliferation rates but a decrease in cell size was observed. Moreover, M2-PK inhibition rescues cells from glucose starvation-induced apoptotic cell death by increasing the metabolic activity. These findings suggest that M2-PK is a metabolic sensor which regulates cell proliferation, cell growth and apoptotic cell death in a glucose supply-dependent manner.
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Affiliation(s)
- Gilles A Spoden
- Department of Cell Metabolism and Differentiation, Institute for Biomedical Aging Research of the Austrian Academy of Sciences, Rennweg 10, 6020 Innsbruck, Austria
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31
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Noske W, Heinsohn A, Hinze R, Lechner S. Sehverschlechterung mit auffälligem Hintergrund. Klin Monbl Augenheilkd 2008. [DOI: 10.1055/s-0028-1110039] [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: 10/21/2022]
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32
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Noske W, Lechner S, Burau H, Hinze R. Behandlungsergebnisse nach intravitrealer Injektion von Bevazicumab (Avastin®) bei okulären Venenverschlüssen. Klin Monbl Augenheilkd 2007. [DOI: 10.1055/s-2007-1004499] [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: 10/21/2022]
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33
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Noske W, Lechner S, Kathke M, Heinsohn A. Koagulationsbehandlung von peripapillären choroidalen Neovaskularisationen. Klin Monbl Augenheilkd 2006. [DOI: 10.1055/s-2006-958216] [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: 10/19/2022]
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34
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Witsch-Baumgartner M, Clayton P, Clusellas N, Haas D, Kelley RI, Krajewska-Walasek M, Lechner S, Rossi M, Zschocke J, Utermann G. Identification of 14 novel mutations in DHCR7 causing the Smith-Lemli-Opitz syndrome and delineation of the DHCR7 mutational spectra in Spain and Italy. Hum Mutat 2006; 25:412. [PMID: 15776424 DOI: 10.1002/humu.9328] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The Smith-Lemli-Opitz syndrome (SLOS) is a phenotypically variable metabolic malformation and mental retardation syndrome for which more than 80 mutations in the DHCR7 disease-causing gene have been described. The DHCR7 mutational spectra differ significantly in different areas of Europe, and several common putative founder mutations account for a substantial fraction of all mutations in some ethnic groups. Here we have analysed 47 SLOS patients and describe 14 newly identified mutations in 18 SLOS patients of Ashkenazi Jewish, Austrian, British, German, Italian, Irish, Polish, Portuguese, and Spanish origins. Half of the new mutations are in the transmembrane domains of the protein. In addition, there were two null mutations, one mutation in the 4th cytoplasmic loop, two mutations in the first and last codons, and three mutations in other regions such as the second cytoplasmic loop and the first endoplasmic loop. The analysis included 20 Spanish and 12 Italian SLOS patients and revealed very different mutation spectra in these patients compared to previously described patients from Czechoslovakia, Germany, Poland, and the UK and implicated p.Thr93Met on the J haplotype as the most frequent Mediterranean founder mutation.
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Affiliation(s)
- M Witsch-Baumgartner
- Department of Medical Biology and Human Genetics, Medical University Innsbruck, Innsbruck, Austria.
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35
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Ironson G, Weiss S, Lydston D, Ishii M, Jones D, Asthana D, Tobin J, Lechner S, Laperriere A, Schneiderman N, Antoni M. The impact of improved self-efficacy on HIV viral load and distress in culturally diverse women living with AIDS: the SMART/EST Women's Project. AIDS Care 2005; 17:222-36. [PMID: 15763716 DOI: 10.1080/09540120512331326365] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [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: 10/26/2022]
Abstract
The purpose of the present study was to determine whether changes in self-efficacy over time would be related to changes in disease progression markers (CD4, viral load) in a sample of women with AIDS. A self-efficacy measure was developed and two sub-scales emerged via factor analysis of 391 HIV-positive women: AIDS Self-efficacy and Cognitive Behavioral Skills Self-efficacy. Subsequently, the sub-scales and an additional adherence self-efficacy item were given to 56 HIV-positive women who were measured at two time points three months apart. Half of these women were randomly assigned to a CB intervention and half to a low intensity comparison condition. Increases in AIDS Self-efficacy over the three-month period were significantly related to increases in CD4 and decreases in viral load. Similarly, increases in Cognitive Behavioral Skills Self-efficacy were significantly related to decreases in distress over time. Findings were maintained within the intervention group alone. Interestingly, increases in cognitive behavioral skills self-efficacy and increases in the self-efficacy adherence item were also significantly related to decreases in viral load. Implications of the findings and suggestions for future research are discussed.
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Affiliation(s)
- G Ironson
- Department of Psychology, University of Miami, PO Box 248185, Coral Gables, FL 33146, USA.
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36
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Schwenteck T, Draeger J, Ruokonen P, Lechner S, Weise M. Klinische Erprobung neuer Augentonometer auf der Basis des internationalen Standards für Augentonometer ISO 8612. Klin Monbl Augenheilkd 2004; 221:1020-5. [PMID: 15599808 DOI: 10.1055/s-2004-813709] [Citation(s) in RCA: 1] [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] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
There is a continuous process of development of new tonometer types following different measurement principles. The impedance measurement method, using the elasticity of the eyeball, allows tonometry even through the eyelid. Two new tonometers based on the impedance principle were investigated by clinical comparison measurements according to the international standard for human eye tonometers ( ISO 8612). The tested tonometers determine the intraocular pressure without topical anaesthesia. The different elastic properties of an individual eyelid and also the different elastic properties of the human eye due to a large variation in rigidity cause serious problems for these measurements. Statistical properties of the two investigated tonometers are presented and discussed. Statements and conclusions about the medical application of these measurement devices for ophthalmologists are made.
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37
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Noske W, Wach T, Lechner S. Zur Problematik des cortisoninduzierten Augendruckanstieges. Klin Monbl Augenheilkd 2004. [DOI: 10.1055/s-2004-837124] [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: 10/19/2022]
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38
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Ruokonen PC, Schwenteck T, Lechner S, Draeger J, Hartmann C. Klinische Evaluierung der dem Impedanz-Prinzip folgenden Tonometer TGDc-01 und ICARE. Klin Monbl Augenheilkd 2004. [DOI: 10.1055/s-2004-837129] [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: 10/19/2022]
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39
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Huss R, von Lüttichau I, Lechner S, Notohamiprodjo M, Seliger C, Nelson P. [Chemokine directed homing of transplanted adult stem cells in wound healing and tissue regeneration]. Verh Dtsch Ges Pathol 2004; 88:170-3. [PMID: 16892549] [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] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
A major challenge in stem cell biology is to study the underlying mechanisms of tissue specific homing and differentiation. Recent results suggest that bone marrow derived stem cells can give rise to multiple cell types. Because chemokines and chemokine receptors are associated with development, differentiation and homing of immune cells, we undertook efforts to study the chemokine receptor expression profile of human adult stem cells to identify their potential role in tissue specific homing prior to transdifferentiation. Using human bone marrow-derived stem cell lines, we could demonstrate functional chemokine receptor expression of various chemokine receptors. The expression of CXCR5 and CCR7, associated with secondary lymphoid organ homing as well as CXCR4 and CCR10, involved in organ specific homing and CXCR3, CCR5 and CCR1, which are involved in inflammation events, suggested a role of chemokine receptors in tissue specific homing of stem cells. To proof the specific homing of stem cells in vivo, we used murine stem cell lines, stably introduced green fluorescent protein under control of CMV promotor into the cells and injected them intravenously into mice. We demonstrate the homing of these stem cells to lymphnode and thymus as well as mucosal tissue, while stem cells home exclusively to a site of lesion during wound healing and tissue regeneration. Our data suggest that chemokine biology may play a pivotal role in the homing of stem cells to specific tissues and niches prior to (trans)differentiation, while the homing changes during tissue damage and other adequate lesions.
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Affiliation(s)
- R Huss
- Pathologisches Institut der Universität München
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40
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Abstract
BACKGROUND AND AIMS Colorectal epithelial cells are prone to malignant transformation. Therefore, identification of differences in gene expression in the process from normal colonic crypts to adenomas with low grade dysplasia is essential for further insights into early tumorigenesis. To achieve this goal, a novel gene expression analysis strategy, screening for expressed transcripts in small histologically defined tissue samples, was performed. METHODS First, laser mediated microdissection was used to isolate normal and adenomatous crypts from colonic cryosections. Then, nested RNA arbitrarily primed polymerase chain reaction (RAP-PCR) for differential display was performed to screen mRNA populations and to generate hybridisation probes for cDNA expression arrays. After evaluation of cDNA expression arrays, differential expression was confirmed at the protein level by immunohistochemistry. RESULTS Evaluation of gene expression profiles of normal versus adenomatous colonic crypts of six different patients revealed, in general, dysregulation of up to 11% of all analysed genes (total number n=588): specifically, p21-rac1 was upregulated in four of six patients, mitogen activated protein kinase (MAPK) p38alpha in three of six patients, and interferon gamma receptor in three of six patients. Conversely, FAST kinase was found to be downregulated in three of six patients, p53 in three of six patients, and thrombospondin 2 in three of six patients. CONCLUSIONS For the first time, distinct gene expression profiles of dysplastic areas within colonic adenomas, using the combination of laser mediated microdissection with RAP-PCR and cDNA expression array, were shown. In these samples, upregulation of proliferation associated genes (ras-oncogene related p21-rac1 and MAPK p38alpha) as well as downregulation of apoptosis related genes (FAST kinase and p53) most likely reflects specific alterations in adenomas with low grade dysplasia. Based on upregulation of p21-rac1 and MAPK p38alpha, activation of the MAPK pathway appears to be an early event in colonic carcinogenesis.
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Affiliation(s)
- S Lechner
- Department of Internal Medicine I, University of Regensburg, D-93042 Regensburg, Germany
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41
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Judex M, Neumann E, Lechner S, Dietmaier W, Ballhorn W, Grifka J, Gay S, Schölmerich J, Kullmann F, Müller-Ladner U. Laser-mediated microdissection facilitates analysis of area-specific gene expression in rheumatoid synovium. Arthritis Rheum 2003; 48:97-102. [PMID: 12528109 DOI: 10.1002/art.10713] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Current approaches to analyzing gene expression in rheumatoid arthritis (RA) synovium are based on RNA isolated either from cultured synovial cells or from synovial biopsy specimens. This strategy does not, in general, allow distinction of specific gene expression between cells originating from different synovial areas, due to potential mixture of expression profiles. Therefore, we established the combination of laser-mediated microdissection (LMM) and differential display to analyze profiles of gene expression in histologically defined areas of rheumatoid synovium. The present study was undertaken to establish parameters for this technique and assess its usefulness for gene expression analysis. METHODS Cryosections derived from RA synovial tissues were used to obtain cell samples from synovial lining versus sublining, using a microbeam laser microscope. RNA was isolated and analyzed by nested RNA arbitrarily primed-polymerase chain reaction (RAP-PCR) for differential display fingerprinting. Differentially expressed bands were cut out, and PCR products were eluted, cloned, and sequenced. Differential expression of identified sequences was confirmed by in situ hybridization and immunohistochemistry analysis. RESULTS Microdissected sections of RA synovial tissue containing approximately 600 cells yielded enough RNA to produce a reproducible RNA fingerprint pattern. Several genes could be identified as being expressed differentially between the synovial lining and the sublining, and their expression could be confirmed at the messenger RNA and protein levels. CONCLUSION The combination of LMM and RAP-PCR presents a valuable tool to obtain novel insights into the area-dependent differential regulation of gene expression in RA synovium. Both known and previously unknown genes were revealed with this technique. This study is the first to demonstrate the potential of this analytic strategy in the investigation of a nonmalignant, multifactorial, inflammatory disease.
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Affiliation(s)
- M Judex
- University of Regensburg, Regensburg, Germany
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42
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Lechner S, Pleyer U, Hartmann C. [Conjunctival mixed injection with membrane development. Ocular involvement in epidermolysis bullosa hereditaria generalisata atrophicans]. Ophthalmologe 2002; 99:960-1. [PMID: 12539746 DOI: 10.1007/s00347-002-0616-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- S Lechner
- Universitäts-Augenklinik Charité, Campus Viorchow Klinikum, Berlin, Germany
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43
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Lechner S, Rüther K, Hartmann C. [Bilateral optic atrophy and slow worsening of vision]. Ophthalmologe 2001; 98:988-9. [PMID: 11699325 DOI: 10.1007/s003470170051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- S Lechner
- Augenklinik der Charité Campus Virchow-Klinikum, Berlin
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44
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Lechner S, Müller-Ladner U, Neumann E, Dietmaier W, Welsh J, Schölmerich J, Rüschoff J, Kullmann F. Use of simplified transcriptors for the analysis of gene expression profiles in laser-microdissected cell populations. J Transl Med 2001; 81:1233-42. [PMID: 11555671 DOI: 10.1038/labinvest.3780337] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [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: 11/08/2022] Open
Abstract
Because colorectal epithelia are prone to malignant transformation, it is important to understand their normal regulation and then to identify differences between the normal cells and the transformed cells. We investigated the gene expression pattern along colonic crypts using a novel gene expression analysis strategy. We combined laser-mediated microdissection of distinct areas within colonic crypts and used modified RNA arbitrarily primed PCR to generate probes for cDNA array hybridization. In the basal part of the crypt, proliferation-related and cell cycle-related genes such as the multifunctional transcription factor e2f-1 or the mismatch-related gene p58/HHR23B were predominantly expressed. In the lumenal part of the crypt, up-regulations of the cysteine protease mch4 and the proto-oncogene c-jun were found. Our findings indicate that e2f1, p58/HHR23B, and mch4 may be involved in key mechanisms leading to malignant transformation in the colonic crypt. Our results also suggest that the technique elucidated here allows identification of gene expression patterns in distinct areas of intestinal tissue samples.
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Affiliation(s)
- S Lechner
- Department of Internal Medicine I, University of Regensburg, Regensburg, Germany
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45
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Lechner S, Schweig F, Rieck P, Anders N, Hartmann C. [Pathologically reduced endothelial cell number despite normal slit-lamp microscopic corneal findings. An important result before cataract surgery]. Ophthalmologe 2001; 98:273-6. [PMID: 11320816 DOI: 10.1007/s003470170162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND A reduced number of endothelial cells increases the risk of corneal decompensation after cataract surgery. It is difficult to quantify the number of endothelial cells using slit-lamp microscopy since normal corneas may also show a reduced number of endothelial cells. MATERIALS AND METHODS We compared the number of endothelial cells pre- and postoperatively in a group of 500 consecutive patients. RESULTS Corneas diagnosed preoperatively with corneae guttata by slit-lamp microscopy may reveal more than 1800 endothelial cells/mm2. These corneas may decompensate after surgery. CONCLUSION We consider the routine use of endothelial microscopy to be a helpful diagnostic tool prior to cataract surgery.
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Affiliation(s)
- S Lechner
- Augenklinik Charité Campus Virchow-Klinikum, Augustenburger Platz 1, 13353 Berlin
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46
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Maurice MM, Nakamura H, Gringhuis S, Okamoto T, Yoshida S, Kullmann F, Lechner S, van der Voort EA, Leow A, Versendaal J, Muller-Ladner U, Yodoi J, Tak PP, Breedveld FC, Verweij CL. Expression of the thioredoxin-thioredoxin reductase system in the inflamed joints of patients with rheumatoid arthritis. Arthritis Rheum 1999; 42:2430-9. [PMID: 10555039 DOI: 10.1002/1529-0131(199911)42:11<2430::aid-anr22>3.0.co;2-6] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To examine the expression of the thioredoxin (TRX)-thioredoxin reductase (TR) system in patients with rheumatoid arthritis (RA) and patients with other rheumatic diseases. METHODS Levels of TRX in plasma and synovial fluid (SF) were measured using enzyme-linked immunosorbent assay. Cellular distribution of TRX was determined by flow cytometry and histochemistry. Cellular expression of TR was studied by in situ messenger RNA (mRNA) hybridization. The effect of oxidative stress and tumor necrosis factor alpha (TNF alpha) on TRX expression by cultured rheumatoid fibroblast-like synoviocytes was studied. RESULTS Significantly increased TRX levels were found in the SF from 22 patients with RA, when compared with plasma levels in the same patients (P < 0.001) and compared with SF TRX levels in 15 patients with osteoarthritis (P < 0.001), 13 patients with gout (P < 0.05), and 9 patients with reactive arthritis (P < 0.0001). The presence of TRX could be demonstrated within the SF-derived mononuclear cells and synovial tissue (ST) of RA patients. Concordantly, expression of TR mRNA was observed in the ST of these patients. Stimulation of synovial fibroblast-like synoviocytes with either H2O2 or TNF alpha induced an increase in the production of TRX. CONCLUSION The data demonstrate significantly increased concentrations of TRX in the SF and ST of RA patients when compared with the levels in patients with other joint diseases. Evidence is presented that the local environment in the rheumatic joint contributes to increased TRX production. Based on its growth-promoting and cytokine-like properties, it is proposed that increased expression of TRX contributes to the disease activity in RA.
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Kullmann F, Judex M, Neudecker I, Lechner S, Jüsten HP, Green DR, Wessinghage D, Firestein GS, Gay S, Schölmerich J, Müller-Ladner U. Analysis of the p53 tumor suppressor gene in rheumatoid arthritis synovial fibroblasts. Arthritis Rheum 1999; 42:1594-600. [PMID: 10446856 DOI: 10.1002/1529-0131(199908)42:8<1594::aid-anr5>3.0.co;2-#] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To determine whether mutations in the tumor suppressor gene p53 may contribute to the transformed-appearing phenotype of rheumatoid arthritis (RA) synovial fibroblasts. METHODS We performed p53 gene mutation analysis using different molecular approaches. Synovial fibroblasts of 10 patients with RA were cultured and RNA and DNA were harvested after 3-5 passages in cell culture. Sequence analysis of all exons of the p53 gene was performed using 3 different techniques: 1) single-strand conformational polymorphism, 2) nonisotopic RNase cleavage assay, and 3) base excision sequence scanning T-scan, followed by sequence analysis of specific gene segments. RESULTS Although p53 antigen could be detected by immunocytochemistry in numerous cultured fibroblasts, gel electrophoresis analysis of products obtained using all 3 methods and subsequent sequence analysis showed no specific mutation pattern in the genome of the synovial fibroblasts from patients in Germany, including the known "hot spots" within the p53 genome. However, p53 mutations were identified in different clones of 3 additional RA synovial fibroblast populations from the United States. Sequence analysis of the p53 promoter did not reveal mutational base changes. CONCLUSION The findings of the study support the hypothesis that the majority of the mutations of the p53 gene observed in RA synovium are not derived from the genome of RA synovial fibroblasts, and that the variability of the mutation pattern reflects, in part, the heterogeneity of the disease.
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Zibert A, Kraas W, Ross RS, Meisel H, Lechner S, Jung G, Roggendorf M. Immunodominant B-cell domains of hepatitis C virus envelope proteins E1 and E2 identified during early and late time points of infection. J Hepatol 1999; 30:177-84. [PMID: 10068093 DOI: 10.1016/s0168-8278(99)80059-2] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
BACKGROUND/AIMS We characterized immunoreactive B-cell domains of hepatitis C virus (HCV) envelope proteins E1 and E2 by a peptide ELISA using sera of patients who were infected by the same isolate of HCV (HCV-AD78). METHODS Fifty-four overlapping peptides which corresponded to the sequence of E1 and E2 of isolate HCV-AD78 were used to detect specific antibodies. Three groups of HCV-AD78 related sera were analyzed. Two groups were from sera obtained at early time points of infection (months 4-15) from patients who later resolved infection (group A), or who later developed chronic disease (group B). Group C sera were from later time points of chronic disease. As a control, sera of chronic HCV patients who did not have HCV-AD78 infection were also analyzed (group D). RESULTS In group A, 25 of the 54 peptides produced OD405 above the cut-off, whereas 17 peptides produced such values in group B. Only 10 and 3 peptides yielded such values in groups C and D, respectively. The overall prevalence of antibodies against peptides was high in the early phase of infection (means of 28.7+/-14.8% and 25.9+/-14.5% in groups A and B, respectively). At later time points of chronic infection (group C), the overall prevalence was lower (mean 18.6+/-15.4%). Group D sera produced the lowest overall prevalence (mean 13.2+/-14.1%). Three peptides, covering aa271-290, aa481-500 and aa551-570, were recognized significantly more frequently (p<0.05) by group A sera than group B sera. CONCLUSIONS We conclude that more linear epitopes of the HCV envelope are recognized with a high prevalence of antibodies, as was suggested previously. However, most B-cell domains of the HCV envelope induce a similarly high antibody response in patients who resolve infection or develop chronic disease.
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Affiliation(s)
- A Zibert
- Institut für Virologie, Universitätsklinikum Essen, Germany
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Lechner S, Mayr R, Francis KP, Prüss BM, Kaplan T, Wiessner-Gunkel E, Stewart GS, Scherer S. Bacillus weihenstephanensis sp. nov. is a new psychrotolerant species of the Bacillus cereus group. Int J Syst Bacteriol 1998; 48 Pt 4:1373-82. [PMID: 9828439 DOI: 10.1099/00207713-48-4-1373] [Citation(s) in RCA: 323] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The Bacillus cereus group comprises the four valid species Bacillus cereus, Bacillus mycoides, Bacillus thuringiensis and bacillus anthracis. Some isolates of B. cereus are known to be psychrotolerant (growth at 7 degrees C or below). Here, specific sequence differences are described between the 16S rDNA, the 23S rDNA, the 16S-23S rDNA spacer region and the genes of the major cold-shock protein homologue cspA in a variety of psychrotolerant and mesophilic B. cereus and B. mycoides strains. Randomly amplified polymorphic DNA analysis using three different primers clearly separated psychrotolerant strains of both species from the rest of the B. cereus group, as did inverse PCR patterns of the rDNA operons. These data strongly support a hitherto unrecognized fifth sub-group within the B. cereus species group comprising psychrotolerant, but not mesophilic, B. cereus strains. Despite the latter finding, the DNA sequences investigated exhibited a high degree of sequence similarity indicating a close relationship between the species of the B. cereus group. Considering the unusual importance of B. cereus in both food poisoning and food spoilage and to avoid merging all species of the group, a new species, Bacillus weihenstephanensis sp. nov., comprising psychrotolerant 'cereus' strains, is proposed. Isolates of the new species grow at 4-7 degrees C but not at 43 degrees C and can be identified rapidly using rDNA or cspA targeted PCR. The type strain is B. weihenstephanensis WSBC 10204T (= DSM 11821T).
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MESH Headings
- Animals
- Bacillus/classification
- Bacillus/isolation & purification
- Bacillus/physiology
- Bacterial Proteins/genetics
- Cold Temperature
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- Genes, rRNA
- Milk/microbiology
- Molecular Sequence Data
- Nucleic Acid Hybridization
- Phylogeny
- Polymerase Chain Reaction
- RNA, Ribosomal, 16S/genetics
- RNA, Ribosomal, 23S/genetics
- Random Amplified Polymorphic DNA Technique
- Sequence Analysis, DNA
- Species Specificity
- Terminology as Topic
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Affiliation(s)
- S Lechner
- Institut für Mikrobiologie, Technische Universität München, Germany
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Lechner S, Rispeter K, Meisel H, Kraas W, Jung G, Roggendorf M, Zibert A. Antibodies directed to envelope proteins of hepatitis C virus outside of hypervariable region 1. Virology 1998; 243:313-21. [PMID: 9568031 DOI: 10.1006/viro.1998.9069] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The relatively high variability of the hepatitis C virus (HCV) envelope proteins E1 and E2 suggests that parts of these proteins other than the hypervariable region 1 (HVR1) might be involved in the induction of virus neutralizing antibodies. To test this hypothesis, two HCV proteins, pE1 and pE2 delta, were generated by in vitro translation. They represent amino acids 174-337 of E1 and 411-688 of E2, respectively, of isolate HCV-AD78; the protein pE2 delta contained no HVR1. As a control, protein pG.HVR1, which represents amino acids 384-410 of HVR1 of isolate HCV-AD78, was expressed separately. These three proteins were used in an immunoprecipitation assay to detect the presence of antiviral antibodies in sera of patients infected with the same isolate of HCV (HCV-AD78). Sera were obtained 4-8 months postinfection from patients who later resolved an acute infection or developed chronic liver disease. A high prevalence of antibodies (up to 85.7%) against pE1 and pE2 delta could be detected in both groups of patients, suggesting that these forms of the HCV envelope proteins contain B-cell epitopes. The antibody responses against proteins pE1 and pE2 delta did not differ significantly between patients with resolving or chronic infection, whereas antibodies against protein pG.HVR1 were associated with resolution of infection. Rabbit antisera raised against pE1 and pE2 delta were tested for their ability to neutralize the binding of HCV to susceptible cells in tissue cultures. The results suggested that although a few B-cell epitopes outside of HVR1 can induce virus neutralizing antibodies, these antibodies are probably not associated with the resolution of infection.
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Affiliation(s)
- S Lechner
- Institut für Virologie, Universitätsklinikum, Essen, Germany
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