Comparison on the genotoxic effects of nuclear vs cytoplasmic irradiation from the alteration ofCD59 gene locus
- 12 Downloads
Using microbeam to irradiate human-hamster hybrid AL cells with defined number of a particles in a highly localized spatial region, this paper showed that cytoplasmic irradiation induced very little toxicity. For example, the cell killing by 4 a particle traversal through the cytoplasm was about 10%, and about 70% cells survived after their cytoplasm was irradiated with 32 a particles. In contrast, the survival fractions for nuclear irradiation at the same doses were 35% and less than 1% respectively. Mutation induction showed that while nuclear irradiation induced 3–4-fold moreCD59 − mutants than cytoplasmic irradiation at equivalent particle traversal, at an equitoxic dose level of 90% survival, the latter exposure mode induced 3.3-fold more mutants than nuclear irradiation. Moreover, using multiplex PCR to analyze five marker genes on chromosome 11 (WT, CAT, PTH, APO-A1 and RAS), the results showed that the majority of mutants induced by cytoplasmic irradiation had retained all of the marker genes analyzed. By comparison, the proportion of mutants suffering loss of additional chromosomal markers increased with increasing number of particle traversal through nuclei.
Keywordsmicrobeam nucleus cytoplasm biological effects
Unable to display preview. Download preview PDF.
- 3.Wu, L. J., Hei, T. K., Randers-Pehrson, R. et al., Columbia University Microbeam: Development of an experimental system for targeting cells individually with counted particles, Nuclear Science and Techniques, 1999, 10(3): 143.Google Scholar
- 14.Thacker, J., The nature of mutants induced by ionizing radiation in cultured hamster cells (III)—Molecular characterization of HPRT-deficient mutants induced by gamma-rays or alpha-particles showing that the majority have deletions of all or part of the HPRT gene, Mutation Research, 1986, 160: 267.PubMedGoogle Scholar