title: Demethylation of genes in animal cells.
abstract: Tissue-specific animal cell genes are usually fully methylated in the germ line and become demethylated in those cell types in which they are expressed. To investigate this process, we inserted a methylated IgG kappa gene into fibroblasts and lymphocytes at various stages of development. The results show that this gene undergoes demethylation only in the mature lymphocytes and therefore suggest that the ability to demethylate a gene is developmentally regulated. These studies were supported by similar experiments using the rat Insulin I gene, and in this case it appears that the cis-acting elements that control demethylation may be different from those responsible for gene activation. The ability to demethylate the housekeeping gene APRT is also under developmental control, because this occurs only in embryonic cells, both in tissue culture and in transgenic mice.
authors.affiliation: Department of Cellular Biochemistry, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
authors.forename: D
authors.initials: D
authors.lastname: Frank
authors.forename: M
authors.initials: M
authors.lastname: Lichtenstein
authors.forename: Z
authors.initials: Z
authors.lastname: Paroush
authors.forename: Y
authors.initials: Y
authors.lastname: Bergman
authors.forename: M
authors.initials: M
authors.lastname: Shani
authors.forename: A
authors.initials: A
authors.lastname: Razin
authors.forename: H
authors.initials: H
authors.lastname: Cedar
mesh_terms: D000228:Adenine Phosphoribosyltransferase / Q000235:genetics; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology; D004247:DNA / Q000235:genetics* / Q000378:metabolism; D005347:Fibroblasts / Q000276:immunology; D005796:Genes; D005803:Genes, Immunoglobulin; D007074:Immunoglobulin G / Q000235:genetics*; D007145:Immunoglobulin kappa-Chains / Q000235:genetics*; D007328:Insulin / Q000235:genetics*; D008745:Methylation; D051381:Rats; D015183:Restriction Mapping; D014162:Transfection
chemical_list: D007074:Immunoglobulin G; D007145:Immunoglobulin kappa-Chains; D007328:Insulin; D004247:DNA; D000228:Adenine Phosphoribosyltransferase