Abstract:
:Targeted gene modification mediated by single-stranded oligonucleotides (SSOs) holds great potential for widespread use in a number of biological and biomedical fields, including functional genomics and gene therapy. By using this approach, specific genetic changes have been created in a number of prokaryotic and eukaryotic systems. In mammalian cells, the precise mechanism of SSO-mediated chromosome alteration remains to be established, and there have been problems in obtaining reproducible targeting efficiencies. It has previously been suggested that the chromatin structure, which changes throughout the cell cycle, may be a key factor underlying these variations in efficiency. This hypothesis prompted us to systematically investigate SSO-mediated gene repair at various phases of the cell cycle in a mammalian cell line. We found that the efficiency of SSO-mediated gene repair was elevated by approximately 10-fold in thymidine-treated S-phase cells. The increase in repair frequency correlated positively with the duration of SSO/thymidine coincubation with host cells after transfection. We supply evidence suggesting that these increased repair frequencies arise from a thymidine-induced slowdown of replication fork progression. Our studies provide fresh insight into the mechanism of SSO-mediated gene repair in mammalian cells and demonstrate how its efficiency may be reliably and substantially increased.
journal_name
Proc Natl Acad Sci U S Aauthors
Wu XS,Xin L,Yin WX,Shang XY,Lu L,Watt RM,Cheah KS,Huang JD,Liu DP,Liang CCdoi
10.1073/pnas.0406991102keywords:
subject
Has Abstractpub_date
2005-02-15 00:00:00pages
2508-13issue
7eissn
0027-8424issn
1091-6490pii
0406991102journal_volume
102pub_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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更新日期:1991-04-01 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
doi:10.1073/pnas.90.20.9616
更新日期:1993-10-15 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:2013-04-09 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.92.17.7705
更新日期:1995-08-15 00:00:00