title: First steps towards systems radiation biology studies concerned with DNA and chromosome structure within living cells.
abstract: For the understanding of radiation action on biological systems like cellular macromolecules (e.g., DNA in its higher structures) a synergistic approach of experiments and quantitative modelling of working hypotheses is necessary. Further on, the influence on calculated results of certain assumptions in such working hypotheses must critically be evaluated. In the present work, this issue is highlighted in two aspects for the case of DNA damage in single cells. First, yields of double-strand breaks and frequency distributions of DNA fragment lengths after ion irradiation were calculated using different assumptions on the DNA target model. Compared to a former target model now a moderate effect due to the inclusion of a spherical chromatin domain model has been found. Second, the influence of assumptions on particular geometric chromosome models on calculated chromosome aberration data is illustrated with two target-modelling approaches for this end point.
authors.affiliation: GSF-Forschungszentrum für Umwelt und Gesundheit, Institut für Strahlenschutz, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany. friedland@gsf.de
authors.forename: Werner
authors.initials: W
authors.lastname: Friedland
authors.forename: Herwig G
authors.initials: HG
authors.lastname: Paretzke
authors.forename: Francesca
authors.initials: F
authors.lastname: Ballarini
authors.forename: Andrea
authors.initials: A
authors.lastname: Ottolenghi
authors.forename: Gregor
authors.initials: G
authors.lastname: Kreth
authors.forename: Christoph
authors.initials: C
authors.lastname: Cremer
mesh_terms: D000818:Animals; D002843:Chromatin / Q000528:radiation effects; D002869:Chromosome Aberrations / Q000528:radiation effects*; D004247:DNA / Q000032:analysis* / Q000528:radiation effects*; D053903:DNA Breaks, Double-Stranded / Q000528:radiation effects; D053938:DNA Fragmentation / Q000528:radiation effects; D006801:Humans; D008954:Models, Biological; D008958:Models, Molecular; D011839:Radiation, Ionizing; D011853:Radiobiology / Q000379:methods*; D012107:Research Design; D049490:Systems Biology / Q000379:methods*
chemical_list: D002843:Chromatin; D004247:DNA