Differential effects of chemical inducers on expression of beta globin genes in murine erythroleukemia cells.

Abstract

Murine erythroleukemia cells are induced to erythrodifferentiate by polar compounds such as dimethyl sulfoxide and hexamethylene bisacetamide as well as fatty acids such as butyric acid and propionic acid. The effect of these inducers on the expression of 2 .beta.-globin genes, .beta.maj and .beta.min, during the course of differentiation of the cells was examined. After 4 days of culture with hexamethylene bisacetamide or dimethyl sulfoxide, the .beta.maj containing Hb (Hbmaj) predominates. In the presence of butyric or propionic acid, after 4 days of culture, relatively equal amounts of Hbmaj and Hbmin are found. When cultured with dimethyl sulfoxide or hexamethylene bisacetamide, murine erythroleukemia cells synthesize more .beta.maj than .beta.min, while about equal amounts of the 2 globins are synthesized in the presence of butyric acid. When poly(A)containing RNA from the cells exposed to different inducers is translated in a wheat germ cell free system, the ratio of .beta.maj to .beta.min synthesized reflects that in whole cells. In a strain of murine erythroleukemia cells resistant to dimethyl sulfoxide (DR-10), the preferential stimulation of .beta.maj synthesis by hexamethylene bisacetamide and .beta.min synthesis by butyric acid is more pronounced than with the dimethyl sulfoxide sensitive cells (DS-19). These data suggest that polar compounds and fatty acids cause different expression of the .beta.maj and .beta.min genes in murine erythroleukemia cells.