Synthesis of globin mRNA in relation to the cell cycle during induced murine erythroleukemia differentiation

The relationship between the synthesis of globin mRNA and the phase of cell cycle was examined in synchronized murine erythroleukemia cells. Cells were synchronized with respect to the cell division cycle either by culture with 2 mM thymidine or 2 mM thymidine followed by 0.5 mM hydroxyurea, which caused cells to accumulate in late G1 or early S (referred to as G1/S boundary). Cells were induced to erythroid differentiation by culture with 280 mM dimethyl sulfoxide or 4 mM hexamethylene bisacetamide. These inducers do not alter the progression of cells from the G1/S boundary through S, G2, and M, but do cause prolongation of the subsequent G1 phase. Accumulation of newly synthesized globin mRNA is first detected when cells are in this G1 phase.