The rapid and decremental change in haem oxygenase mRNA during erythroid differentiation of murine erythroleukaemia cells

Changes in mRNA for haem oxygenase (HO), the rate-limiting enzyme for haem catabolism, were examined in murine Friend-virus transformed erythroleukaemia (MEL) cells while they were induced to undergo erythroid cell differentiation by treatment with dimethyl sulfoxide (DMSO). When MEL cells were treated with 1.5% (v/v) DMSO, a rapid decrease in HO mRNA content was observed (less than 12 h) which reached the lowest value at 18 h (18% of the untreated control). HO mRNA levels remained at substantially lower levels (approximately 50%) than those in untreated controls thereafter. A rapid decline in HO mRNA may be involved in the cellular events that determine the onset of erythroid differentiation.