Globin gene expression in somatic cell hybrids.
Fusions between somatic cell lines have previously yielded evidence for the existence of trans-acting gene regulatory factors. For this reason, we developed a cell line containing a "locked in" human 11-X translocation chromosome (containing the beta-globin-like gene cluster) in MEL cells. The human 11-X chromosome is stably integrated in the "M11-X" cell line, and single-copy human gamma and beta genes are present. After induction with HMBA, M11-X cells produced 500 copies per cell of correctly initiated, processed, and terminated human beta-globin mRNA; authentic human beta-globin chains were also produced at a low level. Despite the presence of normally arranged human gamma-globin genes, no gamma-globin mRNA could be detected after HMBA induction. However, cytosine residues near the gamma-globin gene promoters are completely methylated in these cells, suggesting that the gamma-globin genes may be repressed in part by DNA methylation. The pattern of human globin gene expression in M11-X cells may be affected by methylation and/or by trans-acting factors produced by these tetraploid cells.
D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D004262:DNA Restriction Enzymes; D005786:Gene Expression Regulation; D005914:Globins / Q000235:genetics*; D006801:Humans; D006822:Hybrid Cells / Q000502:physiology*; D004915:Leukemia, Erythroblastic, Acute / Q000235:genetics; D051379:Mice
D005914:Globins; D004262:DNA Restriction Enzymes