title: DNA-repair protein distribution along the tracks of energetic ions.
abstract: A simple model of homogenous chromatin distribution in HeLa-cell nuclei suggests that the track of an energetic ion hits 30 nm chromatin fibers with a mean distance of 0.55 mum. To test this assumption, living HeLa-cells were irradiated at the irradiation setup of the ion microprobe SNAKE using the ion beams provided by the Munich 14 MV tandem accelerator. After irradiation, the distribution of 53BP1 protein foci was studied by immunofluorescence. The observed 53BP1 distribution along the tracks of 29 MeV (7)Li ions and 24 MeV (12)C ions differed significantly from the expectations resulting from the simple chromatin model, suggesting that the biological track structure is determined by cell nuclear architecture with higher order organisation of chromatin.
authors.affiliation: Physik Department E12, TU-München, James-Franck-Strasse, 85748 Garching, Germany. andreas.hauptner@ph.tum.de
authors.forename: A
authors.initials: A
authors.lastname: Hauptner
authors.forename: R
authors.initials: R
authors.lastname: Krücken
authors.forename: C
authors.initials: C
authors.lastname: Greubel
authors.forename: V
authors.initials: V
authors.lastname: Hable
authors.forename: G
authors.initials: G
authors.lastname: Dollinger
authors.forename: G A
authors.initials: GA
authors.lastname: Drexler
authors.forename: M
authors.initials: M
authors.lastname: Deutsch
authors.forename: R
authors.initials: R
authors.lastname: Löwe
authors.forename: A A
authors.initials: AA
authors.lastname: Friedl
authors.forename: S
authors.initials: S
authors.lastname: Dietzel
authors.forename: H
authors.initials: H
authors.lastname: Strickfaden
authors.forename: T
authors.initials: T
authors.lastname: Cremer
mesh_terms: D002843:Chromatin / Q000737:chemistry* / Q000528:radiation effects*; D003198:Computer Simulation; D004247:DNA / Q000737:chemistry* / Q000528:radiation effects*; D004249:DNA Damage; D004260:DNA Repair / Q000528:radiation effects*; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D006367:HeLa Cells; D020450:Heavy Ions; D006801:Humans; D018499:Linear Energy Transfer; D008956:Models, Chemical; D008958:Models, Molecular; D011829:Radiation Dosage
chemical_list: D002843:Chromatin; D004268:DNA-Binding Proteins; D004247:DNA