Hemoglobin synthesis in somatic cell hybrids: coexpression of mouse with human or chinese hamster globin genes in interspecific somatic cell hybrids of mouse erythroleukemia cells.

Somatic cell hybrids were derived by fusion of mouse erythroleukemia cells with fractionated human marrow enriched in erythroblasts, or with chinese hamster fetal liver erythroid cells. Such interspecific hybrid cells, when isolated in suspension culture, had retained nearly all the mouse chromosomes and had lost most of the human or chinese hamster chromosomes. However, two such hybrids (one human, the other hamster) studied 4-6 weeks after fusion, were found to contain several non-mouse chromosomes. RNA extracted from the human marrow x erythroleukemia hybrid annealed equally to both human and mouse globin complementary DNA, indicating that coexpression of the globin genes of each species had occurred in the hybrid cells. Mouse and human mRNA were found to accumulate only after incubation of the cells in 2% dimethylsulfoxide. The chinese hamster x erythroleukemia hybrid appeared to contain a double complement of mouse chromosomes in addition to several chinese hamster chromosomes. After 7 days of incubation in 2% dimethylsulfoxide, [3H]leucine was incorporated into chinese hamster beta-globin and the mouse globin chains. Thus, globin genes from differentiated cells, when introduced into spontaneously proliferating erythroleukemia cells, may be expressed after exposure of the resulting hybrid cells to an agent capable of inducing hemoglobin synthesis in the erythroleukemia cell.