title: Chromatin organization revealed by nanostructure of irradiation induced γH2AX, 53BP1 and Rad51 foci.
abstract: The spatial distribution of DSB repair factors γH2AX, 53BP1 and Rad51 in ionizing radiation induced foci (IRIF) in HeLa cells using super resolution STED nanoscopy after low and high linear energy transfer (LET) irradiation was investigated. 53BP1 and γH2AX form IRIF with same mean size of (540 ± 40) nm after high LET irradiation while the size after low LET irradiation is significantly smaller. The IRIF of both repair factors show nanostructures with partial anti-correlation. These structures are related to domains formed within the chromatin territories marked by γH2AX while 53BP1 is mainly situated in the perichromatin region. The nanostructures have a mean size of (129 ± 6) nm and are found to be irrespective of the applied LET and the labelled damage marker. In contrast, Rad51 shows no nanostructure and a mean size of (143 ± 13) nm independent of LET. Although Rad51 is surrounded by 53BP1 it strongly anti-correlates meaning an exclusion of 53BP1 next to DSB when decision for homologous DSB repair happened.
authors.affiliation: Angewandte Physik und Messtechnik, Universitaet der Bundeswehr Muenchen, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany.
authors.forename: Judith
authors.initials: J
authors.lastname: Reindl
authors.affiliation: Angewandte Physik und Messtechnik, Universitaet der Bundeswehr Muenchen, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Girst
authors.affiliation: Angewandte Physik und Messtechnik, Universitaet der Bundeswehr Muenchen, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany.|Department of Radiation Oncology, Technische Universitaet Muenchen, 81675 Munich, Germany.
authors.forename: Dietrich W M
authors.initials: DW
authors.lastname: Walsh
authors.affiliation: Angewandte Physik und Messtechnik, Universitaet der Bundeswehr Muenchen, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Greubel
authors.affiliation: Angewandte Physik und Messtechnik, Universitaet der Bundeswehr Muenchen, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Schwarz
authors.affiliation: Angewandte Physik und Messtechnik, Universitaet der Bundeswehr Muenchen, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany.|Department of Radiation Oncology, Technische Universitaet Muenchen, 81675 Munich, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Siebenwirth
authors.affiliation: Department of Radiation Oncology, Ludwig-Maximilians-Universitaet Muenchen, 80336 Munich, Germany.
authors.forename: Guido A
authors.initials: GA
authors.lastname: Drexler
authors.affiliation: Department of Radiation Oncology, Ludwig-Maximilians-Universitaet Muenchen, 80336 Munich, Germany.
authors.forename: Anna A
authors.initials: AA
authors.lastname: Friedl
authors.affiliation: Angewandte Physik und Messtechnik, Universitaet der Bundeswehr Muenchen, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany.
authors.forename: Günther
authors.initials: G
authors.lastname: Dollinger
mesh_terms: D002843:Chromatin / Q000235:genetics* / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells; D006657:Histones / Q000378:metabolism*; D006801:Humans; D049329:Nanostructures; D051135:Rad51 Recombinase / Q000378:metabolism*; D011827:Radiation; D000071857:Tumor Suppressor p53-Binding Protein 1 / Q000378:metabolism*
chemical_list: D002843:Chromatin; D006657:Histones; C498301:TP53BP1 protein, human; D000071857:Tumor Suppressor p53-Binding Protein 1; D051135:Rad51 Recombinase