Abstract:
:It is shown that initiation of translation involves several steps. (i) Binding of fMet-tRNA(fMet) to the bacterial 30S ribosomal subunit in the absence of messenger RNA, yielding a 34S complex. This binding is rapid and dependent on initiation factor 2 but not on initiation factor 3. (ii) Binding of messenger RNA to the 34S complex. This binding is slower and depends on initiation factor 3. If R17 RNA is used as messenger, the resulting complex sediments at 46 S. (iii) Joining of a 50S subunit to yield a complete initiation complex. Binding of fMet-tRNA(fMet) not only precedes, but is necessary for, correct binding of messenger RNA to ribosomes. Thus, initiator tRNA may play an active role in the selection of initiation sites in messenger RNA.
journal_name
Proc Natl Acad Sci U S Aauthors
Jay G,Kaempfer Rdoi
10.1073/pnas.71.8.3199subject
Has Abstractpub_date
1974-08-01 00:00:00pages
3199-203issue
8eissn
0027-8424issn
1091-6490journal_volume
71pub_type
杂志文章abstract::Global loss of DNA methylation has been known for decades as an epigenomic aberration associated with carcinogenesis and cancer progression. Loss of DNA methylation affects predominantly repetitive elements, which encompass >50% of the CpG dinucleotides present in the human genome. Because of the lack of an effective ...
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.0913836107
更新日期:2010-04-13 00:00:00
abstract::The C4B isotype of the fourth component of human complement (C4) displays 3- to 4-fold greater hemolytic activity than does its other isotype C4A. This correlates with differences in their covalent binding efficiencies to erythrocytes coated with antibody and complement C1. C4A binds to a greater extent when C1 is on ...
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.87.17.6868
更新日期:1990-09-01 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.88.24.11256
更新日期:1991-12-15 00:00:00
abstract::Excitation-evoked Ca(2+) influx is the fastest and most ubiquitous chemical trigger for cellular processes, including neurotransmitter release, muscle contraction, and gene expression. The voltage dependence and timing of Ca(2+) entry are thought to be functions of voltage-gated calcium (CaV) channels composed of a ce...
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.1411127112
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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.87.15.5672
更新日期:1990-08-01 00:00:00
abstract::The hypernociceptive effects of cytokines [TNF-alpha, keratinocyte-derived chemokine (KC), and IL-1beta] and their participation in carrageenan (Cg)-induced inflammatory hypernociception in mice were investigated. Nociceptor sensitization (hypernociception) was quantified with an electronic version of the von Frey fil...
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.0409225102
更新日期:2005-02-01 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.0903361106
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.86.11.4185
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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doi:10.1073/pnas.0704380104
更新日期:2007-09-25 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.85.21.8057
更新日期:1988-11-01 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.77.11.6720
更新日期:1980-11-01 00:00:00
abstract::Most paleo-episodes of ocean acidification (OA) were either too slow or too small to be instructive in predicting near-future impacts. The end-Cretaceous event (66 Mya) is intriguing in this regard, both because of its rapid onset and also because many pelagic calcifying species (including 100% of ammonites and more 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.1418604112
更新日期:2015-05-26 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.2016650117
更新日期:2020-11-10 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
doi:10.1073/pnas.0701099104
更新日期:2007-06-12 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.1420188112
更新日期:2015-02-03 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.92.24.11175
更新日期:1995-11-21 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:2012-05-08 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
doi:10.1073/pnas.76.2.806
更新日期:1979-02-01 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:1974-05-01 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.83.19.7221
更新日期:1986-10-01 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
doi:10.1073/pnas.0704030104
更新日期:2007-11-06 00:00:00
abstract::The recent discovery of small molecules targeting the cytochrome bc 1 :aa 3 in Mycobacterium tuberculosis triggered interest in the terminal respiratory oxidases for antituberculosis drug development. The mycobacterial cytochrome...
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.1706139114
更新日期:2017-07-11 00:00:00
abstract::Recombination in some intervals of the map of phage lambda is associated with more DNA synthesis than in other intervals. Blockage of DNA synthesis by high temperature in a host temperature-sensitive for DNA synthesis results in the relative reduction of recombinant frequencies in those regions having the larger amoun...
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.69.12.3598
更新日期:1972-12-01 00:00:00
abstract::Interfacial zones between tissues provide specialized, transitional junctions central to normal tissue function. Regenerative medicine strategies focused on multiple cell types and/or bi/tri-layered scaffolds do not provide continuously graded interfaces, severely limiting the integration and biological performance of...
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.0801988105
更新日期:2008-08-26 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.1422336112
更新日期:2015-06-09 00:00:00
abstract::Mutations of MECP2 (Methyl-CpG Binding Protein 2) cause Rett syndrome. As a chromatin-associated multifunctional protein, how MeCP2 integrates external signals and regulates neuronal function remain unclear. Although neuronal activity-induced phosphorylation of MeCP2 at serine 421 (S421) has been reported, the full sp...
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.0811648106
更新日期:2009-03-24 00:00:00
abstract::The phytochrome family of informational photoreceptors has a central role in regulating light-responsive gene expression, but the mechanism of intracellular signal transduction has remained elusive. In a genetic screen for T DNA-tagged Arabidopsis mutants affected in early signaling intermediates, we identified poc1 (...
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.96.10.5832
更新日期:1999-05-11 00:00:00
abstract::A series of recombinant plasmids was generated in Escherichia coli in which the TEM beta-lactamase translocon (TnA) was inserted into the small plasmid RSF1010. RSF1010 is a 5.5 X 10(6) dalton nonconjugative plasmid which confers resistance to streptomycin and sulfonamide. The recombinant plasmids can be classified in...
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.72.9.3623
更新日期:1975-09-01 00:00:00
abstract::Expression of the two X-linked loci glucose-6-phosphate dehydrogenase (G6PD; EC 1.1.1.49) and hypoxanthine:guanine phosphoribosyltransferase (HGPRT; EC 2.4.2.8) was studied in single hair follicles of two females who were heterozygous for both of these genes (double heterozygotes). The coupling phase for these two loc...
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.68.7.1425
更新日期:1971-07-01 00:00:00
abstract::In a recently discovered class of oncogenes, GTPase-inhibiting mutations constitutively activate alpha subunits of signal-transducing guanine nucleotide-binding proteins (G proteins). Somatic mutations in a subclass of endocrine tumors are found in the arginine-179 codon of the alpha subunit of Gi2 (alpha i2), creatin...
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.88.16.7031
更新日期:1991-08-15 00:00:00