Abstract:
:Cyclization/cleavage of the 2-(p-nitrophenyl) phosphate ester of propylene glycol is catalyzed by imidazole and, much more effectively, by Zn2+ with imidazole. In the latter case, the mechanism involves simultaneous Lewis acid/base catalysis. Similar Zn2+ and imidazole catalysis of cyclization/cleavage is seen with the dinucleotide 3',5'-UpU (uridylyluridine). Again, the zinc system is much more effective than is catalysis by imidazole alone, and in this case simultaneous Lewis acid/base catalysis substitutes for the sequential proton acid/base catalysis seen with polynucleotides or dinucleotides and imidazole buffer catalysts. A mechanism is proposed for catalysis of RNA cleavage by the enzyme ribonuclease A, and the relationship of that mechanism to the action of the enzyme model systems is discussed.
journal_name
Proc Natl Acad Sci U S Aauthors
Breslow R,Huang DL,Anslyn Edoi
10.1073/pnas.86.6.1746subject
Has Abstractpub_date
1989-03-01 00:00:00pages
1746-50issue
6eissn
0027-8424issn
1091-6490journal_volume
86pub_type
杂志文章abstract::We isolated erythroleukemic cell lines arrested at different levels of the erythroid differentiation pathway. One cell line (CB5), established from mice infected with the helper-independent Friend murine leukemia virus (F-MuLV), exhibited properties similar to those of the normal erythroid progenitor burst-forming cel...
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.80.12.3721
更新日期:1983-06-01 00:00:00
abstract::The Sleeping Beauty (SB) transposon system can integrate foreign sequences of DNA in the genome of mouse somatic cells eliciting long-term expression in vivo. This technology holds great promise for human gene therapy as a nonviral technology to deliver therapeutic genes. SB also provides a means to study the effects ...
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.0502974102
更新日期:2005-11-22 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
doi:10.1073/pnas.0900668106
更新日期:2009-06-09 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.86.7.2408
更新日期:1989-04-01 00:00:00
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pub_type: 杂志文章
doi:10.1073/pnas.82.13.4414
更新日期:1985-07-01 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.96.16.8855
更新日期:1999-08-03 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.87.19.7433
更新日期:1990-10-01 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:1993-10-01 00:00:00
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更新日期:2016-07-12 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.0912402107
更新日期:2010-01-05 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.1323408111
更新日期:2014-07-08 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:2020-10-27 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.0400752101
更新日期:2004-08-24 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.1412372111
更新日期:2014-11-11 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.0609009103
更新日期:2006-12-12 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.1008285107
更新日期:2010-07-27 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.0702012104
更新日期:2007-10-09 00:00:00
abstract::The Schiff base adducts of glyceraldehyde with hemoglobin undergo Amadori rearrangement to form stable ketoamine structures; this reaction is similar to the nonenzymic glucosylation of proteins. In the present studies the analogous rearrangement of the Schiff base adducts of glycolaldehyde with proteins has been demon...
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.80.12.3590
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
pub_type: 杂志文章
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更新日期:2009-08-04 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:1992-08-01 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
doi:10.1073/pnas.0812874106
更新日期:2009-03-10 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:2011-09-13 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.73.4.1159
更新日期:1976-04-01 00:00:00
abstract::Employing a cell-free chromatin transcription system that recapitulates progesterone receptor (PR)-mediated transcription in vivo, we have investigated further the coactivator functions of steroid receptor coactivator-1 (SRC-1) in terms of its functional domains as well as cooperation with other coactivators in PR tra...
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.231474798
更新日期:2001-10-23 00:00:00
abstract::The exo isomer of aflatoxin B1 (AFB1) 8,9-epoxide appears to be the only product of AFB1 involved in reaction with DNA and reacts with the N7 atom of guanine via an SN2 reaction from an intercalated state. Although the epoxide hydrolyzes rapidly in H2O (0.6 s-1 at 25 degrees C), very high yields of DNA adduct result. ...
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:1997-06-10 00:00:00
abstract::The versatility of CRISPR-Cas endonucleases as a tool for biomedical research has led to diverse applications in gene editing, programmable transcriptional control, and nucleic acid detection. Most CRISPR-Cas systems, however, suffer from off-target effects and unpredictable nonspecific binding that negatively impact ...
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:2020-05-26 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.1207829109
更新日期:2012-07-03 00:00:00
abstract::Regeneration of appendages is frequent among invertebrates as well as some vertebrates. However, in mammals this has been largely relegated to digit tip regeneration, as found in mice and humans. The regenerated structures are formed from a mound of undifferentiated cells called a blastema, found just below the site o...
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.1118017108
更新日期:2011-12-20 00:00:00
abstract::Somatic hypermutation (SHM) and class-switch recombination (CSR) of the Ig gene require both the transcription of the locus and the expression of activation-induced cytidine deaminase (AID). During CSR, AID decreases the amount of topoisomerase I (Top1); this decrease alters the DNA structure and induces cleavage in t...
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.1114522108
更新日期:2011-11-29 00:00:00