title: Isolation and characterization of variant clones of Chinese hamster cells after treatment with irradiated 5-iodouridine.
abstract: Variant clones were isolated from cultured Chinese hamster Don cells after treatment with irradiated 5-iodouridine. The following characters of a primary variant clone, C-11 and a secondary variant clone, C-24 were compared with those of the original clone C-1: colony-forming activity, growth rate in the presence of irradiated and unirradiated 5-iodouridine, distribution of chromosome numbers and cell cohesion. The variant clones C-11 and C-24 were partially resistant to unirradiated 5-iodouridine at lower concentration and C-24 cells were slightly resistant to short-term treatment with irradiated 5-iodouridine. Unlike clines C-1 and C-11 the variant clone C-24 showed no lag phase on growth in 5-iodouridine medium. The modal numbers of the chromosomes of all three clones were 22, like that of normal Chinese hamster diploid cells. Of the three clones, the variant C-24 cells showed the least mutual cohesion and the original C-1 cells showed the most. The possibility that an alteration in cellular membrane might be related to an increase in the resistance to radiosensitizing agents are discussed.
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002460:Cell Line; D002875:Chromosomes; D002999:Clone Cells; D006224:Cricetinae; D014644:Genetic Variation; D007065:Idoxuridine / Q000494:pharmacology* / Q000528:radiation effects; D007621:Karyotyping; D010641:Phenotype; D011003:Ploidies; D011831:Radiation Genetics
chemical_list: D007065:Idoxuridine