title: Regulation of methotrexate polyglutaminate formation in Ehrlich ascites carcinoma cells by endogenous folate pool.
abstract: The conversion of methotrexate to poly-gamma-glutamyl derivatives in Ehrlich ascites carcinoma cells which are characterized by different pools of endogenous folates is described. The cells in which folate pool was high (the 5-fluorodeoxy-uridine-resistant cell line) the ability to convert methotrexate to its polyglutamate derivatives was much lower than in the cells in which folate pool was smaller (the parental cell line). When the cellular folate pool was reduced by treatment of the cells with lysolecithin, a similar methotrexate polyglutamate concentration in both cell lines was observed. These data suggest that cellular folate pool has a regulatory effect on methotrexate polyglutamate synthesis.
mesh_terms: D000818:Animals; D002286:Carcinoma, Ehrlich Tumor / Q000378:metabolism*; D005492:Folic Acid / Q000378:metabolism*; D007700:Kinetics; D008727:Methotrexate / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism; D051379:Mice; D010452:Peptide Biosynthesis; D011099:Polyglutamic Acid / Q000031:analogs & derivatives / Q000096:biosynthesis* / Q000302:isolation & purification
chemical_list: D011099:Polyglutamic Acid; C014085:methotrexate polyglutamate; D005492:Folic Acid; D008727:Methotrexate