Developmental regulation of fetal to adult globin gene switching in human fetal erythroid x mouse erythroleukemia cell hybrids.
Human fetal erythroid x murine erythroleukemia cell hybrids undergo human fetal (gamma) to adult (beta) globin gene switching in vitro under the control of a mechanism located on human chromosome 11. We investigated whether this mechanism acts in cis or in trans by preparing hybrid cells containing marked fragments of the gamma and beta genes known to switch in transgenic mice. In these cells the chromosomally introduced human globin locus undergoes the fetal to adult globin gene switch. In contrast, the marked globin gene fragments were expressed at all stages of hybrid development. These results suggest that either the mechanism of switching acts in cis or that sequences present in the chromosomal globin locus but missing from the transfected globin gene fragments mediate its action.
Division of Medical Genetics, University of Washington, Seattle 98195.
T
T
Enver
M
M
Brice
J
J
Karlinsey
G
G
Stamatoyannopoulos
T
T
Papayannopoulou
D000818:Animals; D002880:Chromosomes, Human, Pair 11; D003001:Cloning, Molecular; D004912:Erythrocytes / Q000166:cytology*; D004920:Erythropoiesis; D005812:Genes, Switch; D005914:Globins / Q000235:genetics*; D006801:Humans; D006822:Hybrid Cells; D004915:Leukemia, Erythroblastic, Acute; D008099:Liver / Q000166:cytology / Q000196:embryology; D051379:Mice; D012260:Ribonucleases / Q000378:metabolism; D014162:Transfection; D014407:Tumor Cells, Cultured
D005914:Globins; D012260:Ribonucleases