Abstract:
:The technique of self-sustained sequence replication allows isothermal amplification of DNA and RNA molecules in vitro. This method relies on the activities of a reverse transcriptase and a DNA-dependent RNA polymerase to amplify specific nucleic acid sequences. We have modified this protocol to allow selective amplification of RNAs that catalyze a particular chemical reaction. During an in vitro RNA evolution experiment employing this modified system, a unique class of "selfish" RNAs emerged and replicated to the exclusion of the intended RNAs. Members of this class of selfish molecules, termed RNA Z, amplify efficiently despite their inability to catalyze the target chemical reaction. Their amplification requires the action of both reverse transcriptase and RNA polymerase and involves the synthesis of both DNA and RNA replication intermediates. The proposed amplification mechanism for RNA Z involves the formation of a DNA hairpin that functions as a template for transcription by RNA polymerase. This arrangement links the two strands of the DNA, resulting in the production of RNA transcripts that contain an embedded RNA polymerase promoter sequence.
journal_name
Proc Natl Acad Sci U S Aauthors
Breaker RR,Joyce GFdoi
10.1073/pnas.91.13.6093subject
Has Abstractpub_date
1994-06-21 00:00:00pages
6093-7issue
13eissn
0027-8424issn
1091-6490journal_volume
91pub_type
杂志文章abstract::Phospholipids containing photolysable carbene precursors (beta-trifluoro-alpha-diazopropionoxy and m-diazirinophenoxy groups) in omega-positions of sn-2 fatty acyl chains were prepared. Photolysis of their vesicles produced crosslinked products in 40-60% yields. Crosslinking was mostly intermolecular and occurred by c...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.76.6.2595
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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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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:1994-01-18 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:1995-01-03 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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doi:10.1073/pnas.93.12.6064
更新日期:1996-06-11 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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doi:10.1073/pnas.88.20.9171
更新日期:1991-10-15 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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更新日期:2006-01-10 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,评审
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更新日期:2008-07-15 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:1979-07-01 00:00:00
abstract::Purified dicyclohexylcarbodiimide-sensitive ATPase (TF0-F1) from thermophilic bacterium PS3 is composed of a water soluble part with ATP hydrolytic activity (TF1) and a water insoluble moiety (TF0). All of the five subunits (alpha, beta, gamma, delta, and epsilon) of TF1 were isolated. TF1 was reconstituted from the f...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1977-03-01 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:1989-07-01 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:1983-04-01 00:00:00
abstract::Two RNA fractions have been isolated and purified from both oncogenic and nononcogenic strains of Agrobacterium tumefaciens. Both RNAs are capable of inducing the formation of transplantable tumors when introduced at wound sites in stems of Datura stramonium plants. One of these RNA fractions was found to be bound to ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.71.5.1585
更新日期:1974-05-01 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:1988-04-01 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:1989-04-01 00:00:00