Abstract:
:The receptor for acetylcholine was partially purified by affinity chromatography of an extract in Triton X-100 of membrane fragments from electric tissue. The receptor was assayed, after its reduction with dithiothreitol, by reaction with the affinity-alkylating agent, [methyl-(3)H]4-(N-maleimido)-benzyltrimethylammonium iodide. Alternative labeling procedures, one useful for routine assay of picomole quantities of receptor and the other for labeling larger quantities of receptor, are described. The purified receptor specifically incorporated about 3 nmol of label per mg of protein. This incorporation was blocked by pretreatment of the receptor with Naja naja siamensis neurotoxin. The rate of the affinity reaction was similar to that found with membrane fragments and with intact electroplax. Furthermore, as in intact electroplax, [(3)H]4-(N-maleimido)-benzyltrimethylammonium iodide reacted 5000-fold faster with the reduced receptor than did [(14)C]N-ethylmaleimide. When purified receptor was labeled with [(3)H]4-(N-maleimido)-benzyltrimethylammonium iodide and subjected to electrophoresis on polyacrylamide gels in dodecyl sulfate and dithiothreitol, three major protein bands were observed. Only one of these, however, contained (3)H activity; its mobility indicated a molecular weight of 40,000.
journal_name
Proc Natl Acad Sci U S Aauthors
Karlin A,Cowburn Ddoi
10.1073/pnas.70.12.3636subject
Has Abstractpub_date
1973-12-01 00:00:00pages
3636-40issue
12eissn
0027-8424issn
1091-6490journal_volume
70pub_type
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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.85.23.9346
更新日期:1988-12-01 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:2002-08-20 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.080572297
更新日期:2000-05-09 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.86.11.4292
更新日期:1989-06-01 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:1980-08-01 00:00:00
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更新日期:2018-06-26 00:00:00
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更新日期:2006-11-07 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:2011-10-11 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:1989-04-01 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:2008-11-11 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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更新日期:2019-12-17 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.0710355105
更新日期:2008-02-12 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.0931425100
更新日期:2003-05-13 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:2012-03-06 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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更新日期:2004-11-02 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:1987-02-01 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.84.18.6491
更新日期:1987-09-01 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:1974-04-01 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:2014-04-29 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:2010-12-14 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:1999-12-21 00:00:00
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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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更新日期:2015-11-10 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:2003-03-04 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
doi:10.1073/pnas.84.13.4572
更新日期:1987-07-01 00:00:00
abstract::We present a phylogenetic analysis to determine whether a given tRNA molecule was established in evolution before its cognate aminoacyl-tRNA synthetase. The earlier appearance of tRNA versus their metabolically related enzymes is a prediction of the RNA world theory, but the available synthetase and tRNA sequences pre...
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.95.19.11295
更新日期:1998-09-15 00:00:00
abstract::To determine whether bacterial ribosomes recognize a distinguishing feature in the immediate vicinity of actual initiator codons or are directed to these sites through involvement of other portion(s) of the mRNA molecule, the interaction between ribosomes and defined (32)P-labeled initiator fragments from R17 RNA was ...
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.70.9.2605
更新日期:1973-09-01 00:00:00