Early changes in ornithine decarboxylase activity and polyamines during erythroid differentiation of Friend leukemia cells.
Induction of cytosolic L-ornithine decarboxylase (ODC) activity in cultures of Friend erythroleukemia cells by seeding in fresh medium was suppressed by treatment with several differentiation inducers. The levels of suppression after 3 h treatment were about 60% at 20 mM nicotinamide, 30% at 1.5% dimethyl sulfoxide (DMSO), and 20% at 5 mM hexamethylene bisacetamide (HMBA). Tracer experiments using [3H]ornithine to determine newly accumulated polyamines including putrescine revealed that the accumulation was suppressed by treatment (18 h) with the inducers. Furthermore, results of polyamine determination by high-pressure liquid chromatography showed that the cellular polyamine content in differentiation-induced cells was lower than those of uninduced cells in early (18 h after inducer treatment) stages of differentiation. Accordingly, it is suggested that cytosolic ODC levels virtually represent the rate of accumulation of intracellular polyamines in the early period of differentiation.
D000818:Animals; D002262:Carboxy-Lyases / Q000378:metabolism*; D002454:Cell Differentiation; D002478:Cells, Cultured; D005622:Friend murine leukemia virus; D004915:Leukemia, Erythroblastic, Acute / Q000378:metabolism*; D007942:Leukemia, Experimental / Q000378:metabolism; D051379:Mice; D009955:Ornithine Decarboxylase / Q000378:metabolism*; D011073:Polyamines / Q000378:metabolism*
D011073:Polyamines; D002262:Carboxy-Lyases; D009955:Ornithine Decarboxylase