Comparison of gamma-radiation-induced accumulation of ataxia telangiectasia and control cells in G2 phase.
Recent reports from a number of laboratories have linked radiosensitivity in ataxia telangiectasia (A-T) to a large and prolonged block of some cells in G2 phase. Previous results from this laboratory, largely with one Epstein-Barr virus-transformed A-T lymphoblastoid cell line, presented evidence for a dramatic increase in the number of cells in G2 phase over controls during a 24-h period post irradiation. We describe here a study of the effect of gamma-radiation on G2 phase delay in several A-T cell lines. Based on previous results with several cell lines 24 h post irradiation was selected as the optimum time to discriminate between G2 phase delay in control and A-T cells. All A-T homozygotes showed a significantly greater number of cells in G2 phase, 24 h post irradiation, than observed in controls. A more prolonged delay in G2 phase after irradiation was seen in different A-T cell types that included lymphoblastoid cells, fibroblasts and SV40-transformed fibroblasts. At the radiation dose used it was not possible to distinguish A-T heterozygotes from controls.
Bates
P R
PR
Clinical Research Centre, Royal Brisbane Hospital, Queensland, Australia.
Lavin
M F
MF
D001260:Ataxia Telangiectasia; D002460:Cell Line; D002472:Cell Transformation, Viral; D005347:Fibroblasts / Q000166:cytology / Q000528:radiation effects; D005434:Flow Cytometry; D005720:Gamma Rays; D004854:Herpesvirus 4, Human / Q000235:genetics; D006579:Heterozygote; D006801:Humans; D007399:Interphase / Q000528:radiation effects*; D013539:Simian virus 40 / Q000235:genetics