Abstract:
:B-lymphocyte-specific class switch recombination is known to occur between pairs of 2- to 10-kb switch regions located immediately upstream of the immunoglobulin constant heavy-chain genes. Others have shown that the recombination is temporally correlated with the induction of transcription at the targeted switch regions. To determine whether this temporal correlation is due to a mechanistic linkage, we have developed an extrachromosomal recombination assay that closely recapitulates DNA deletional class switch recombination. In this assay, the rate of recombination is measured between 24 and 48 hr posttransfection. We find that recombinants are generated in a switch sequence-dependent manner. Recombination occurs with a predominance within B-cell lines representative of the mature B-cell stage and within a subset of pre-B-cell lines. Transcription stimulates the switch sequence-dependent recombination. Importantly, transcription activates recombination only when directed in the physiologic orientation but has no effect when directed in the nonphysiologic orientation.
journal_name
Proc Natl Acad Sci U S Aauthors
Daniels GA,Lieber MRdoi
10.1073/pnas.92.12.5625subject
Has Abstractpub_date
1995-06-06 00:00:00pages
5625-9issue
12eissn
0027-8424issn
1091-6490journal_volume
92pub_type
杂志文章abstract::The structural features that determine tRNA(Ala) acceptor identity have been studied with amber-suppressor tRNAs in Escherichia coli cells. Previous work established that a wobble pair composed of guanosine at position 3 and uridine at position 70 (G3-U70) in the acceptor helix of tRNA(Ala) is a determinant of the mol...
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: 历史文章,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:1998-12-08 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:1985-10-01 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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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.76.11.5755
更新日期:1979-11-01 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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更新日期:1994-12-06 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:2000-03-28 00:00:00
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更新日期:2017-11-07 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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更新日期:1985-01-01 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:1983-06-01 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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更新日期:1973-04-01 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:1989-12-01 00:00:00