Mutational effects of γ-Rays and carbon ion beams on arabidopsis seedlings

To assess the mutational effects of radiation on vigorously proliferating plant tissue,the mutation spectrum was analyzed with arabidopsis seedlings using the plasmid-rescue method. transgenic plants containing the escherichia coli rpsl gene were irradiated with γ-rays and carbon ion beams (320-mev 12c6+),and mutations in the rpsl gene were analyzed. mutant frequency increased significantly following irradiation by γ-rays,but not by 320-mev 12c6+. mutation spectra showed that both radiations increased the frequency of frameshifts and other mutations,including deletions and insertions,but only γ-rays increased the frequency of total base substitutions. these results suggest that the type of dna lesions which cause base substitutions were less often induced by 320-mev 12c6+ than by γ-rays in arabidopsis seedlings. furthermore,γ-rays never increased the frequencies of g:c to t:a or a:t to c:g transversions,which are caused by oxidized guanine; 320-mev 12c6+,however,produced a slight increase in both transversions. instead,γ-rays produced a significant increase in the frequency of g:c to a:t transitions. these results suggest that 8-oxoguanine has little effect on mutagenesis in arabidopsis cells. © the author 2013. published by oxford university press on behalf of the japan radiation research society and japanese society for therapeutic radiology and oncology.