Isolation of a revertant clone from a variant embryonal carcinoma cell line deficient in metabolic co-operation☆

Abstract A revertant clone with restored capacity for metabolic cooperation has been isolated from the cooperation-defective variant embryonal carcinoma cell line R5/3. The properties of the revertant clone provide evidence that deficiencies shown by R5/3 in intercellular transfer of nucleotides and sodium ions are the result of a common genetic lesion which can be dissociated from a secondary lesion causing increased thioguanine resistance and from an increase in ploidy.