Laser UV microirradiation of interphase nuclei and post-treatment with caffeine
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Laser UV microirradiation of Chinese hamster interphase cells combined with caffeine post-treatment produced different patterns of chromosome damage in mitosis following irradiation of a small area of the nucleus that may be classified in three categories: I) intact metaphase figures, II) chromosome damage confined to a small area of the metaphase spread, III) mitotic figures with damage on all chromosomes. Category III might be the consequence of a non-localized distortion of nuclear metabolism. By contrast, category II may reflect localized DNA damage induced by microirradiation, which could not be efficiently repaired due to the effect of caffeine. If this interpretation is right, in metaphase figures of category II chromosome damage should occur only at the irradiation site. The effect might then be used to investigate neighbourhood relationships of individual chromosomes in the interphase nucleus.
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- Barr, H. J., Ellison, J. R.: Ectopic pairing of chromosome regions containing chemically similar DNA. Chromosoma (Berl.) 39, 53–61 (1972)Google Scholar
- Nur, U.: Random arrangement of chromosomes in a radial metaphase configuration. Chromosoma (Berl.) 40, 263–267 (1973)Google Scholar
- Sakharov, V. N., Voronkova, L. N., Pyruzyan, L. A., Lomakina, L. Y.: Partial chromosomal labelling induced by ultraviolet microbeam irradiation of mitotic cells. Nature (Lond.) 260, 784–785 (1976)Google Scholar
- Schwarzacher, H. G.: Chromosomes in mitosis and interphase. Berlin-Heidelberg-New York: Springer 1976Google Scholar
- Singh, R. J., Röbbelen, G., Okamoto, M.: Somatic association at interphase studied by Giemsa banding technique. Chromosoma (Berl.) 56, 265–273 (1976)Google Scholar