Reduction in p53 synthesis during differentiation of Friend-erythroleukemia cells. Correlation with the commitment to terminal cell division.

The process of cell differentiation in Friend-erythroleukemia cells was accompanied by 80-90% inhibition of p53 synthesis. This decrease was found to be linked to changes in cell-cycle distribution characteristics of the growth arrest program during differentiation rather than to the induction of the globin genes. The shut-off in the expression of p53 always preceded the specific arrest of cells in the G0/G1 phase. Interferon did not modulate down the expression of p53 if added to transformed non-induced Friend-erythroleukemia cells; however, it slightly enhanced the extent of reduction in p53 synthesis if added during cell differentiation, thus suggesting a differential effect of interferon between cells at different stages of differentiation.