Abstract:
:DNA fragments encoding the mouse steroid 21-hydroxylase (C21 or Cyp21A1) gene are de novo methylated when introduced into the mouse adrenocortical tumor cell line Y1 by DNA-mediated gene transfer. Although CCGG sequences within the C21 gene are de novo methylated, CCGG sites within flanking vector sequences, other mammalian gene sequences driven by the C21 promoter, and the neomycin-resistance gene, which was cotransfected with the C21 gene, do not become methylated. At least two separate signals for de novo methylation are encoded within the gene since three fragments derived from the C21 gene were methylated de novo. Specific de novo methylation of C21-derived sequences does not occur in L cells or Y1 kin8 cells; this suggests that the cellular factors needed for de novo methylation of the C21 gene are not ubiquitous. Most DNA sequences are not de novo methylated when introduced into somatic cells and DNA sequences other than the C21 gene are not de novo methylated when introduced into Y1 cells. Several groups have suggested that de novo methylation occurs in early embryonic cells and that somatic cells strictly maintain their methylation pattern by a semiconservative methyltransferase. Our results suggest that de novo methylation of specific nucleotide sequences can occur in some mammalian somatic cells.
journal_name
Proc Natl Acad Sci U S Aauthors
Szyf M,Schimmer BP,Seidman JGdoi
10.1073/pnas.86.18.6853subject
Has Abstractpub_date
1989-09-01 00:00:00pages
6853-7issue
18eissn
0027-8424issn
1091-6490journal_volume
86pub_type
杂志文章abstract::The cochlear implant (CI) is a neuroprosthesis that allows profoundly deaf patients to recover speech intelligibility. This recovery goes through long-term adaptative processes to build coherent percepts from the coarse information delivered by the implant. Here we analyzed the longitudinal postimplantation evolution ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0609419104
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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
pub_type: 杂志文章
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更新日期:2016-03-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2004-06-22 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2010-09-07 00:00:00
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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
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2006-07-11 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1980-06-01 00:00:00
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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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更新日期:1990-08-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2006-05-02 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1997-11-11 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.96.6.2907
更新日期:1999-03-16 00:00:00