Interaction of two cytoplasmic erythroid differentiation-inducing factors in mouse erythroleukemia cells.
Our previous cell fusion experiments have suggested that the in vitro erythroid differentiation of mouse erythroleukemia cells is the result of a synergistic reaction involving two intracellular differentiation-inducing factors (DIF); these were subsequently demonstrated in the cytoplasmic fraction of mouse erythroleukemia cells. Here, we present experimental evidence indicating that, under conditions in which the two factors (DIF-I and DIF-II) are coinduced, a new factor, which can trigger erythroid differentiation upon introduction into undifferentiated mouse erythroleukemia cells, is produced in the cells. A similar factor was also generated in vitro after the incubation of partially purified DIF-I and DIF-II. We found that protein phosphatases could substitute for DIF-II. These and other experiments suggest that protein dephosphorylation at a tyrosine residue(s) is involved in the generation of the new factor.
Watanabe
T
T
Institute of Applied Microbiology, University of Tokyo, Japan.
Oishi
M
M
D028341:Activins; D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D003593:Cytoplasm / Q000378:metabolism*; D007265:Inhibins / Q000378:metabolism*; D004915:Leukemia, Erythroblastic, Acute / Q000378:metabolism* / Q000473:pathology; D051379:Mice
D028341:Activins; D007265:Inhibins