title: Chromatin Ring Formation at Plant Centromeres.
abstract: We observed the formation of chromatin ring structures at centromeres of somatic rye and Arabidopsis chromosomes. To test whether this behavior is present also in other plant species and tissues we analyzed Arabidopsis, rye, wheat, Aegilops and barley centromeres during cell divisions and in interphase nuclei by immunostaining and FISH. Furthermore, structured illumination microscopy (super-resolution) was applied to investigate the ultrastructure of centromere chromatin beyond the classical refraction limit of light. It became obvious, that a ring formation at centromeres may appear during mitosis, meiosis and in interphase nuclei in all species analyzed. However, varying centromere structures, as ring formations or globular organized chromatin fibers, were identified in different tissues of one and the same species. In addition, we found that a chromatin ring formation may also be caused by subtelomeric repeats in barley. Thus, we conclude that the formation of chromatin rings may appear in different plant species and tissues, but that it is not specific for centromere function. Based on our findings we established a model describing the ultrastructure of plant centromeres and discuss it in comparison to previous models proposed for animals and plants.
authors.affiliation: Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben Stadt Seeland, Germany.
authors.forename: Veit
authors.initials: V
authors.lastname: Schubert
authors.affiliation: Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) GaterslebenStadt Seeland, Germany; Department of Genetics, Biotechnology, Plant Breeding and Seed Science, Russian State Agrarian University - Moscow Timiryazev Agricultural AcademyMoscow, Russia.
authors.forename: Alevtina
authors.initials: A
authors.lastname: Ruban
authors.affiliation: Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben Stadt Seeland, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Houben
keywords: CENH3; centromere organization; interphase nucleus; meiosis; mitosis; repetitive DNA; super-resolution microscopy