Facilitated detection of chromosome break and repair at low levels of ionizing radiation by addition of wortmannin to G1-type PCC fusion incubation Export

@article{citeulike:2518767, abstract = {We have measured rejoining kinetics of chromosome breaks using a modified cell fusion-based premature chromosome condensation (PCC) technique in confluent cultures of normal human fibroblasts irradiated at low doses of X-rays. In order to enhance the sensitivity of the fusion-based PCC assay, we added a DNA double strand break (DSB) repair inhibitor wortmannin during the incubation period for PCC/fusion process resulting in a significantly higher yield of G1-type chromosome breaks. The initial number of chromosome breaks (without repair) gave a linear dose response with about 10 breaks per cell per Gy which is about two times higher than the value with the conventional G1-type PCC method. The chromosome rejoining kinetics at 0.5 and 2.0 Gy X-rays reveal a bi-phasic curve with both a fast and a slow component. The fast component (0-30 min) is nearly identical for both doses, but the slow component for 2 Gy kinetics is much slower than that for 0.5 Gy, indicating that the process occurring during this period may be crucial for the ultimate fate of irradiated cells. The chromosome rejoining kinetics obtained here is similar to that of other methods of detecting DNA DSB repair such as the [gamma]H2AX assay. Our chromosome repair assay is useful for evaluating the accuracy of other assays measuring DNA DSB repair at doses equal or less than 0.5 Gy of ionizing radiation.}, author = {Okada, Maki and Saito, Shiori and Okayasu, Ryuichi}, citeulike-article-id = {2518767}, citeulike-linkout-0 = {http://dx.doi.org/10.1016/j.mrgentox.2004.04.004}, citeulike-linkout-1 = {http://www.sciencedirect.com/science/article/B6T2D-4CNJDT5-1/2/2601e848e849aad5070272172166189a}, day = {8}, doi = {10.1016/j.mrgentox.2004.04.004}, journal = {Mutation Research/Genetic Toxicology and Environmental Mutagenesis}, keywords = {fusionpcc, highlet}, month = {August}, number = {1-2}, pages = {11--17}, posted-at = {2008-03-12 09:05:22}, priority = {3}, title = {Facilitated detection of chromosome break and repair at low levels of ionizing radiation by addition of wortmannin to G1-type PCC fusion incubation}, url = {http://dx.doi.org/10.1016/j.mrgentox.2004.04.004}, volume = {562}, year = {2004} }

TY - JOUR ID - citeulike:2518767 L3 - citeulike-article-id:2518767 N2 - We have measured rejoining kinetics of chromosome breaks using a modified cell fusion-based premature chromosome condensation (PCC) technique in confluent cultures of normal human fibroblasts irradiated at low doses of X-rays. In order to enhance the sensitivity of the fusion-based PCC assay, we added a DNA double strand break (DSB) repair inhibitor wortmannin during the incubation period for PCC/fusion process resulting in a significantly higher yield of G1-type chromosome breaks. The initial number of chromosome breaks (without repair) gave a linear dose response with about 10 breaks per cell per Gy which is about two times higher than the value with the conventional G1-type PCC method. The chromosome rejoining kinetics at 0.5 and 2.0 Gy X-rays reveal a bi-phasic curve with both a fast and a slow component. The fast component (0-30 min) is nearly identical for both doses, but the slow component for 2 Gy kinetics is much slower than that for 0.5 Gy, indicating that the process occurring during this period may be crucial for the ultimate fate of irradiated cells. The chromosome rejoining kinetics obtained here is similar to that of other methods of detecting DNA DSB repair such as the [gamma]H2AX assay. Our chromosome repair assay is useful for evaluating the accuracy of other assays measuring DNA DSB repair at doses equal or less than 0.5 Gy of ionizing radiation. IS - 1-2 JF - Mutation Research/Genetic Toxicology and Environmental Mutagenesis EP - 17 TI - Facilitated detection of chromosome break and repair at low levels of ionizing radiation by addition of wortmannin to G1-type PCC fusion incubation VL - 562 SP - 11 KW - fusionpcc KW - highlet AU - Okada, Maki AU - Saito, Shiori AU - Okayasu, Ryuichi PY - 2004/08/08/ UR - http://dx.doi.org/10.1016/j.mrgentox.2004.04.004 ER -