Abstract：
:Axonal guidance is key to the formation of neuronal circuitry. Semaphorin 3A (Sema 3A; previously known as semaphorin III, semaphorin D, and collapsin-1), a secreted subtype of the semaphorin family, is an important axonal guidance molecule in vitro and in vivo. The molecular mechanisms of the repellent activity of semaphorins are, however, poorly understood. We have now found that the secreted semaphorins contain a short sequence of high homology to hanatoxin, a tarantula K(+) and Ca(2+) ion channel blocker. Point mutations in the hanatoxin-like sequence of Sema 3A reduce its capacity to repel embryonic dorsal root ganglion axons. Sema 3A growth cone collapse activity is inhibited by hanatoxin, general Ca(2+) channel blockers, a reduction in extracellular or intracellular Ca(2+), and a calmodulin inhibitor, but not by K(+) channel blockers. Our data support an important role for Ca(2+) in mediating the Sema 3A response and suggest that Sema 3A may produce its effects by causing the opening of Ca(2+) channels.
journal_name
Proc Natl Acad Sci U S Aauthors
Behar O,Mizuno K,Badminton M,Woolf CJdoi
10.1073/pnas.96.23.13501keywords:
subject
Has Abstractpub_date
1999-11-09 00:00:00pages
13501-5issue
23eissn
0027-8424issn
1091-6490journal_volume
96pub_type
杂志文章abstract：:In a study of juvenile hormone-regulated gene expression, we isolated an anonymous cDNA representing a message that was strongly suppressed by juvenile hormone in the fat body of the cockroach Blaberus discoidalis. The protein deduced from the cDNA sequence showed compelling resemblance in sequence to the transferrins...
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.90.4.1320
更新日期：1993-02-15 00:00:00
abstract：:How useful can machine learning be in a quantum laboratory? Here we raise the question of the potential of intelligent machines in the context of scientific research. A major motivation for the present work is the unknown reachability of various entanglement classes in quantum experiments. We investigate this question...
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.1714936115
更新日期：2018-02-06 00:00:00
abstract：:Glycosyl phosphates are shown to be activated to stereospecific nucleophilic substitution reactions by precisely tailored bis-thiourea catalysts. Enhanced reactivity and scope is observed with phosphate relative to chloride leaving groups. Stronger binding (Km) to the H-bond donor and enhanced reactivity of the comple...
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.1811186116
更新日期：2019-01-02 00:00:00
abstract：:A leading hypothesis explaining Phanerozoic mass extinctions and associated carbon isotopic anomalies is the emission of greenhouse, other gases, and aerosols caused by eruptions of continental flood basalt provinces. However, the necessary serial relationship between these eruptions, isotopic excursions, and extincti...
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.1001706107
更新日期：2010-04-13 00:00:00
abstract：:Gene expression is controlled by sequence-specific transcription factors (TFs), which bind to regulatory sequences in DNA. TF binding occurs in nucleosome-depleted regions of DNA (NDRs), which generally encompass regions with lengths similar to those protected by nucleosomes. However, less is known about where within ...
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.1804663115
更新日期：2018-07-24 00:00:00
abstract：:The failure to induce self-tolerance of simian virus 40 large tumor antigen (T antigen) expressed in the pancreatic beta cells of transgenic mice results in an autoimmune response against this protein and the cells that synthesize it. In every transgenic mouse with delayed onset of T-antigen expression and consequent ...
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.87.19.7487
更新日期：1990-10-01 00:00:00
abstract：:Efficient single nucleotide polymorphism (SNP) genotyping methods are necessary to accomplish many current gene discovery goals. A crucial element in large-scale SNP genotyping is the number of individual biochemical reactions that must be performed. An efficient method that can be used to simultaneously amplify a set...
journal_title：Proceedings of the National Academy of Sciences of the United States of America
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doi：10.1073/pnas.261710699
更新日期：2002-03-05 00:00:00
abstract：:We have shown recently that the temporal order of antioxidant consumption in human blood plasma exposed to a constant flux of aqueous peroxyl radicals is ascorbate = protein thiols greater than bilirubin greater than urate greater than alpha-tocopherol and that detectable lipid peroxidation starts only after ascorbate...
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.86.16.6377
更新日期：1989-08-01 00:00:00
abstract：:Exposure of murine hepatoma (Hepa 1c1c7) cells to a variety of chemical agents known to protect animals against the neoplastic, mutagenic, and other toxic effects of chemical carcinogens results in dose- and time-dependent inductions of NAD(P)H:quinone reductase (EC 1.6.99.2). This enzyme protects against quinone toxi...
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.83.3.787
更新日期：1986-02-01 00:00:00
abstract：:We report a simplified method for culturing fetal central nervous system cells predominantly inducing neurons that grow, differentiate, and live in vitro for as long as 10 weeks. These central nervous system cells form a confluent cell culture in which about 80% of the cells are fully differentiated neurons producing ...
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.77.1.653
更新日期：1980-01-01 00:00:00
abstract：:A cylindrical detonating explosive behaves like a non-Newtonian viscous fluid emerging from a cylindrical pipe. The expression for non-Newtonian viscous flow has been applied to detonating explosives. The resultant fit to emerging flame fronts from detonation is excellent for a wide variety of detonating explosives bo...
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.77.10.5575
更新日期：1980-10-01 00:00:00
abstract：:Awareness that our planet is a self-supporting biosphere with sunlight as its major source of energy for life has resulted in a long-term historical fascination with the workings of self-supporting ecological systems. However, the studies of such systems have never entered the canon of ecological or evolutionary tools...
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.1904326116
更新日期：2019-06-04 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.1211902109
更新日期：2012-11-27 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.73.2.317
更新日期：1976-02-01 00:00:00
abstract：:The crystal structures of Escherichia coli thymidylate kinase (TmpK) in complex with P1-(5'-adenosyl)-P5-(5'-thymidyl)pentaphosphate and P1-(5'-adenosyl)P5-[5'-(3'-azido-3'-deoxythymidine)] pentaphosphate have been solved to 2.0-A and 2.2-A resolution, respectively. The overall structure of the bacterial TmpK is very ...
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.95.24.14045
更新日期：1998-11-24 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.0408565102
更新日期：2005-05-31 00:00:00
abstract：:A close study of the metabolic regulation of hexose transport in a hamster fibroblast mutant, highly defective in the enzyme phosphoglucose isomerase (PGI mutant), reveals the requirement for at least three vectors for transport regulation. The downward regulation of the hexose transport system, called the "transport ...
journal_title：Proceedings of the National Academy of Sciences of the United States of America
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doi：10.1073/pnas.81.4.1126
更新日期：1984-02-01 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
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更新日期：1976-12-01 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：2012-02-28 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.76.5.2288
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更新日期：2005-07-19 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.91.25.12159
更新日期：1994-12-06 00:00:00
abstract：:The conservation of developmental functions exerted by Antp-class homeoproteins in protostomes and deuterostomes suggested that homologs with related functions are present in diploblastic animals. Our phylogenetic analyses showed that Antp-class homeodomains belong either to non-Hox or to Hox/paraHox families. Among t...
journal_title：Proceedings of the National Academy of Sciences of the United States of America
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doi：10.1073/pnas.97.9.4493
更新日期：2000-04-25 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.1808734116
更新日期：2019-05-28 00:00:00
abstract：:The effects of predator intimidation on habitat use and behavior of prey species are rarely quantified for large marine vertebrates over ecologically relevant scales. Using state space movement models followed by a series of step selection functions, we analyzed movement data of concurrently tracked prey, bowhead whal...
journal_title：Proceedings of the National Academy of Sciences of the United States of America
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doi：10.1073/pnas.1911761117
更新日期：2020-03-24 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.0504628102
更新日期：2005-12-20 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.1614778114
更新日期：2017-07-18 00:00:00
abstract：:A topological model of the DNA binding site for the cyclic AMP receptor protein (CRP) is presented. A consensus sequence drawn from the known CRP binding sites has several symmetrical subregions that are spatially resolved onto different faces of the DNA helix. Consideration of available biochemical and genetic data s...
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.78.4.2213
更新日期：1981-04-01 00:00:00
abstract：:Muscle plasminogen activators (PAs), such as urokinase-like PA and, to a lesser extent, tissue PA, increase dramatically after denervation induced by axotomy. The PA/plasmin system has also been implicated in degradation of specific components of the muscle fiber basement membrane after local activation of plasminogen...
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.87.8.2926
更新日期：1990-04-01 00:00:00
abstract：:The data reported here demonstrate that a preparation extracted from nonpathogenic mycobacteria such as Mycobacterium smegmatis and hereafter referred to as interphase material protected mice against Ehrlich ascitic carcinoma, L-1210 leukemia, and another syngeneic lymphoid leukemia. Furthermore, mice treated by this ...
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.72.9.3656
更新日期：1975-09-01 00:00:00
