Relationship between globin mRNA accumulation and commitment to terminal cell differentiation in inducer sensitive and resistant erythroleukemia variants

The relationship between the kinetics of commitment to terminal cell differentiation and the rates of accumulation of globin mRNA has been examined during the induction of erythroid differentiation by polar/apolar chemical inducers in murine erythroleukemia cells (MELC), under conditions of more and less rapid commitment. Two differentiation inducers and three MELC variants have been studied. Hexamethylene bisacetamide (HMBA) initiates more rapid commitment than does dimethylsulfoxide (Me2SO). MELC variant DR10 is resistant to induction by Me2SO and responds sluggishly to HMBA, in comparison with the DS19- Sc9 variant. V3.17, an MELC variant resistant to low concentrations of vincristine, shows increased sensitivity to the inducers and an accelerated rate of commitment to terminal differentiation compared with DS19-Sc9. It is demonstrated that commitment and the actual expression of differentiation, as measured by the accumulation of alpha- , beta maj-, and beta min-globin mRNA, are temporally coordinated functions during induced differentiation of a transformed cell line by exposure to polar/apolar agents.