Abstract:
:Previous studies have defined transcriptional control elements, in addition to the promoters, that both lie near individual human beta-globin locus genes and have been implicated in their differential stage-specific regulation during development (i.e., are believed to directly participate in hemoglobin switching). We have reinvestigated the activities during erythropoiesis that might be conferred by two of the more intensively analyzed of these elements, the epsilon-globin gene 5' silencer and the beta-globin gene 3' enhancer, by deleting them from a yeast artificial chromosome that spans the human beta-globin locus, and then analyzing transgenic mice for expression of all of the human genes. These studies show that sequences within the epsilon-globin "silencer" are not only required for silencing but are also required for activation of epsilon-globin transcription; furthermore, deletion of the silencer simultaneously reduced gamma-globin transcription during the yolk sac stage of erythroid development. Analysis of the adult beta-globin gene 3' enhancer deletion showed that its deletion affects only that gene.
journal_name
Proc Natl Acad Sci U S Aauthors
Liu Q,Bungert J,Engel JDdoi
10.1073/pnas.94.1.169subject
Has Abstractpub_date
1997-01-07 00:00:00pages
169-74issue
1eissn
0027-8424issn
1091-6490journal_volume
94pub_type
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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