Cytosine arabinoside plus hemin treatment of a human erythroid cell line, KMOE, strongly induces embryonic, fetal, and adult beta-like globin genes

A variety of regimens were utilized on KMOE cells to maximally raise globin mRNA levels for the purpose of improving the usefullness of this line for globin gene studies. Steady-state mRNA levels of embryonic (epsilon), fetal (gamma) and adult (beta) globin genes were assayed by the S1-nuclease protection method before and after exposure to inducing compounds. Exposure of KMOE cells to cytosine arabinoside and hemin leads to over 20-fold increases in beta- and gamma-globin mRNA steady-state levels, and an over 60-fold increase in epsilon-globin mRNA level. Exposure to cytosine arabinoside alone induced beta- and epsilon-globin but not gamma-globin gene expression. The alpha-like globin genes (zeta and alpha) were also monitored but found to be poorly expressed and not significantly inducible. The presence of epsilon-globin mRNA and the lack of alpha-globin mRNA distinguishes this line, KMOE-EL, from the KMOE sublines previously described.