Regulated expression of the human β-globin gene family in murine erythroleukaemia cells.

Chemically induced differentiation of cultured murine erythroleukaemia (MEL) cells results in a several hundred-fold increase in transcription of the adult mouse globin genes and thus serves as a model for gene activation during erythropoiesis. One approach to study gene regulation in this system has been to analyse the expression of foreign globin genes introduced into MEL cells. By introducing cosmid DNA containing the human adult(beta), fetal(gamma) and embryonic(epsilon)-globin genes, we have shown here that expression of the beta, but not the gamma or epsilon genes, is regulated during MEL differentiation. Regulated expression of the human beta-globin gene was observed when it was introduced either as part of the intact globin gene cluster or as an individual gene with 1.5 kilobases (kb) of 5' flanking DNA. Transcription from a herpes simplex virus (HSV) promoter adjacent to the thymidine kinase (tk) gene is also inducible in MEL cells.