Abstract：
:The structural gene for plasmid-mediated ampicillin resistance resides upon a 3.2 X 10(6) dalton transposable sequence (TnA) flanked by short inverted repeated sequences that accompany its insertion. TnA was transposed to pMB8, a 1.8 X 10(6) dalton derivative of the colicingenic plasmid ColE1. Random deletions were introduced in the resultant 5 X 10(6) dalton recombinant plasmid by a combination of nuclease treatments in vitro. From this set of deletions a subset was isolated that contained deletions affecting the transposition of TnA. The deletions were mapped by digestion with restriction nucleases and electron microscopic analysis of DNA hetero-duplexes and were found to include one of the inverted repeated sequences or lie in the central portion of TnA. Complementation experiments were attempted between these plasmids and another compatible plasmid carrying a deletion in TnA that abolished its ampicillin resistance. The results of the deletion data indicate that approximately 2 X 10(6) daltons of TnA is required for transposition; the complementation experiments suggest that the terminal inverted repetition and the central region of TnA play different essential roles in TnA transposition.
journal_name
Proc Natl Acad Sci U S Aauthors
Heffron F,Bedinger P,Champoux JJ,Falkow Sdoi
10.1073/pnas.74.2.702subject
Has Abstractpub_date
1977-02-01 00:00:00pages
702-6issue
2eissn
0027-8424issn
1091-6490journal_volume
74pub_type
杂志文章abstract：:The development of Drosophila organ discs can be arrested by culturing them in adult male flies. These aged discs lose some of their differentiation competence and form incomplete imaginal structures. The more advanced the aging, the greater the loss of competence. Discs made to differentiate prematurely show deficien...
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.72.11.4674
更新日期：1975-11-01 00:00:00
abstract：:Reactive oxygen species (ROS) are well-known accelerants of aging, but, paradoxically, we show that physiological levels of ROS extend life span in pupae of the moth Helicoverpa armigera, resulting in the dormant state of diapause. This developmental switch appears to operate through a variant of the conventional insu...
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.1711042114
更新日期：2017-09-12 00:00:00
abstract：:Memory CD8 T cells provide durable protection against diverse intracellular pathogens and can be broadly segregated into distinct circulating and tissue-resident populations. Paradigmatic studies have demonstrated that circulating memory cells can be further divided into effector memory (Tem) and central memory (Tcm) ...
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.2008571117
更新日期：2020-10-13 00:00:00
abstract：:The nucleotide sequence of the recognition site for the restriction-modification enzyme of Escherichia coli B (SB site) has been determined. The recognition site is a 15-nucleotide sequence consisting of the trimer 5'TGA3', followed by an 8-nucleotide domain of variable sequence, which in turn is followed by tetramer ...
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.75.5.2266
更新日期：1978-05-01 00:00:00
abstract：:Blood oxygen level-dependent functional MRI (fMRI) constitutes a powerful neuroimaging technology to map brain-wide functions in response to specific sensory or cognitive tasks. However, fMRI mapping of the vestibular system, which is pivotal for our sense of balance, poses significant challenges. Physical constraints...
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.1812453116
更新日期：2019-05-14 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.1008301107
更新日期：2010-11-30 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.0308197101
更新日期：2004-06-22 00:00:00
abstract：:The double-stranded RNA (dsRNA)-dependent protein kinase (PKR) is induced as part of the IFN response in mammals and acts to shut down protein synthesis by the phosphorylation of eukaryotic initiation factor 2alpha (eIF2alpha). In fish, a PKR-like kinase activity has been detected, but the enzyme responsible has elude...
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.0408714102
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： 历史文章,杂志文章
doi：10.1073/pnas.1017647108
更新日期：2011-05-03 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.1716009114
更新日期：2017-11-14 00:00:00
abstract：:Profilin2 (PFN2) is a target of the embryonic stem cell (ESC)-enriched miR-290 family of microRNAs (miRNAs) and an actin/dynamin-binding protein implicated in endocytosis. Here we show that the miR-290-PFN2 pathway regulates many aspects of ESC biology. In the absence of miRNAs, PFN2 is up-regulated in ESCs, with a re...
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.2002750117
更新日期：2020-08-25 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.2014896117
更新日期：2020-12-08 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.88.19.8602
更新日期：1991-10-01 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.90.24.11513
更新日期：1993-12-15 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
doi：10.1073/pnas.0705312104
更新日期：2007-07-17 00:00:00
abstract：:Whereas NF-kappaB has potent antiapoptotic function in most cell types, it was reported that in pancreatic beta cells it serves a proapoptotic function and may contribute to the pathogenesis of autoimmune type 1 diabetes. To investigate the role of beta cell NF-kappaB in autoimmune diabetes, we produced transgenic mic...
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.0610690104
更新日期：2007-02-06 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.90.13.6208
更新日期：1993-07-01 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.78.11.7134
更新日期：1981-11-01 00:00:00
abstract：:Saccharomyces cerevisiae is one of the most important model organisms and has been a valuable asset to human civilization. However, despite its extensive use in the last 9,000 y, the existence of a seasonal cycle outside human-made environments has not yet been described. We demonstrate the role of social wasps as vec...
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.1208362109
更新日期：2012-08-14 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：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.95.22.12944
更新日期：1998-10-27 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.69.5.1165
更新日期：1972-05-01 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.1402627111
更新日期：2014-11-11 00:00:00
abstract：:An intense (up to 20 muA/cm(2)) steady electrical current enters the anterior or nurse cell end of the growing follicle (or oocyte-nurse cell complex) of the Cecropia moth and is balanced by a more diffuse current leaving elsewhere. In late growth stages, the total transfollicular current is about 100 nA. Moreover, a ...
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.76.3.1328
更新日期：1979-03-01 00:00:00
abstract：:Prenatal unilateral enucleation in mammals causes an extensive anatomical reorganization of visual pathways. The remaining eye innervates the entire extent of visual subcortical and cortical areas. Electrophysiological recordings have shown that the retino-geniculate connections are retinotopically organized and genic...
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.90.23.11142
更新日期：1993-12-01 00:00:00
abstract：:We have cloned and partially characterized 24 loci from the human genome which are complementary to U1, U2, or U3, the three major species of small nuclear RNA (snRNA) in HeLa cells. When compared to the known U1 (human) and U2 (rat) snRNA sequences, the DNA sequences we report here for the complementary regions from ...
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.78.2.810
更新日期：1981-02-01 00:00:00
abstract：:Somatic fungal hyphae are generally assumed to elongate at steady linear rates when grown under constant environmental conditions with ample nutrients. However, patterns of pulsed hyphal elongation were detected during apparent steady growth of hyphal tips in fungi from several major taxonomic groups (Oomycetes, Pythi...
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.91.25.12228
更新日期：1994-12-06 00:00:00
abstract：:The multifunctional Ca2+/calmodulin-dependent protein kinase purified from rat brain cytosol undergoes an intramolecular self-phosphorylation or autophosphorylation. Autophosphorylation produces two strikingly different effects on kinase activity that are dependent on the level of ATP used in the reaction. At low but ...
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.83.24.9497
更新日期：1986-12-01 00:00:00
abstract：:Distribution studies disclosed that all major cerebral arteries and cortical arterioles of the cat were invested with fine varicose nerve fibers that contained calcitonin gene-related peptide (CGRP)-like immunoreactivity; the trigeminal ganglia likewise contained CGRP immunoreactivity. Sequential immunostaining with a...
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.83.15.5731
更新日期：1986-08-01 00:00:00
abstract：:Inhibition of human purine nucleoside phosphorylase (PNP) stops growth of activated T-cells and the formation of 6-oxypurine bases, making it a target for leukemia, autoimmune disorders, and gout. Four generations of ribocation transition-state mimics bound to PNP are structurally characterized. Immucillin-H (K*i(1/4)...
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.0913439107
更新日期：2010-03-16 00:00:00
