title: Guanine quadruplex structures localize to heterochromatin.
abstract: Increasing amounts of data support a role for guanine quadruplex (G4) DNA and RNA structures in various cellular processes. We stained different organisms with monoclonal antibody 1H6 specific for G4 DNA. Strikingly, immuno-electron microscopy showed exquisite specificity for heterochromatin. Polytene chromosomes from Drosophila salivary glands showed bands that co-localized with heterochromatin proteins HP1 and the SNF2 domain-containing protein SUUR. Staining was retained in SUUR knock-out mutants but lost upon overexpression of SUUR. Somatic cells in Macrostomum lignano were strongly labeled, but pluripotent stem cells labeled weakly. Similarly, germline stem cells in Drosophila ovaries were weakly labeled compared to most other cells. The unexpected presence of G4 structures in heterochromatin and the difference in G4 staining between somatic cells and stem cells with germline DNA in ciliates, flatworms, flies and mammals point to a conserved role for G4 structures in nuclear organization and cellular differentiation.
authors.affiliation: European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands.
authors.forename: Roland F
authors.initials: RF
authors.lastname: Hoffmann
authors.affiliation: Department of Biochemistry, Erasmus University Medical Center, Dr. Molewaterplein 50, NL-3015 GE Rotterdam, The Netherlands.
authors.forename: Yuri M
authors.initials: YM
authors.lastname: Moshkin
authors.affiliation: European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands.
authors.forename: Stijn
authors.initials: S
authors.lastname: Mouton
authors.affiliation: Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands.
authors.forename: Nicola A
authors.initials: NA
authors.lastname: Grzeschik
authors.affiliation: Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands.
authors.forename: Ruby D
authors.initials: RD
authors.lastname: Kalicharan
authors.affiliation: Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands.
authors.forename: Jeroen
authors.initials: J
authors.lastname: Kuipers
authors.affiliation: Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands.
authors.forename: Anouk H G
authors.initials: AH
authors.lastname: Wolters
authors.affiliation: Faculty of Medicine, Kyoto University, Kyoto 606-8501, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Nishida
authors.affiliation: Department of Biochemistry, Erasmus University Medical Center, Dr. Molewaterplein 50, NL-3015 GE Rotterdam, The Netherlands Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia.
authors.forename: Aleksander V
authors.initials: AV
authors.lastname: Romashchenko
authors.affiliation: Helios Medical Centre Wuppertal, Paediatrics Centre, Witten/Herdecke University, Wuppertal, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Postberg
authors.affiliation: Institute of Cell Biology, Centre for Biomedical Education and Research, Witten/Herdecke University, Witten, Germany.
authors.forename: Hans
authors.initials: H
authors.lastname: Lipps
authors.affiliation: European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia.
authors.forename: Eugene
authors.initials: E
authors.lastname: Berezikov
authors.affiliation: Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands.
authors.forename: Ody C M
authors.initials: OC
authors.lastname: Sibon
authors.affiliation: Department of Cell Biology, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands.
authors.forename: Ben N G
authors.initials: BN
authors.lastname: Giepmans
authors.affiliation: European Research Institute for the Biology of Ageing, University of Groningen, University Medical Centre Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands Terry Fox Laboratory, British Columbia Cancer Agency and Department of Medicine, University of British Columbia Vancouver, BC, V5Z 1L3, Canada p.m.lansdorp@umcg.nl.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Lansdorp
mesh_terms: D000818:Animals; D016798:Ciliophora; D004330:Drosophila; D054856:G-Quadruplexes; D005854:Germ Cells / Q000378:metabolism; D006147:Guanine; D006570:Heterochromatin / Q000737:chemistry* / Q000235:genetics*; D006657:Histones / Q000378:metabolism; D007515:Islets of Langerhans / Q000378:metabolism / Q000648:ultrastructure; D010986:Platyhelminths; D059007:Polytene Chromosomes / Q000737:chemistry / Q000235:genetics; D051381:Rats
chemical_list: D006570:Heterochromatin; D006657:Histones; D006147:Guanine