Abstract:
:During an investigation of the role of ions in growth regulation, it was found that ethylene diamine tetraacetate (EDTA) inhibits DNA synthesis about 10-fold in cultures of chick embryo cells, while ethylene glycol bis(beta-amino ethyl ether)-N,N'-tetraacetate has no effect. RNA synthesis is only slightly inhibited by EDTA, and protein synthesis is unaffected. EDTA is inhibitory to DNA synthesis at a concentration much lower than that of either Ca(++) or Mg(++) present in the growth medium. The inhibition is prevented by the addition of Zn(++) at a much lower concentration than that of the EDTA. Other metal ions are ineffective. The inhibition of DNA synthesis only becomes apparent after more than 6 hr of incubation with EDTA, and descends to its final level by 15 hr. Complete restoration of the original rate of DNA synthesis is achieved within 8-10 hr by the addition of Zn(++). The low rate of DNA synthesis that occurs in a density-inhibited culture, is refractory to further inhibition by EDTA. Rous sarcoma cells are less sensitive to inhibition by EDTA than normal cells, but the sensitivity of both is increased by reducing the concentration of Ca(++) in the medium. DNA synthesis in mouse 3T3 cells is also inhibited by EDTA. It is concluded that Zn(++) is a continuing requirement for DNA synthesis in cultured vertebrate cells, and it is suggested that the availability of Zn(++) within the cell may play a role in the regulation of cell multiplication.
journal_name
Proc Natl Acad Sci U S Aauthors
Rubin Hdoi
10.1073/pnas.69.3.712subject
Has Abstractpub_date
1972-03-01 00:00:00pages
712-6issue
3eissn
0027-8424issn
1091-6490journal_volume
69pub_type
杂志文章abstract::Idiopathic pulmonary fibrosis (IPF)/usual interstitial pneumonia is a ravaging condition of progressive lung scarring and destruction. Anti-inflammatory therapies including corticosteroids have limited efficacy in this ultimately fatal disorder. An important unmet need is to identify new agents that interact with key ...
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.1001520107
更新日期:2010-08-10 00:00:00
abstract::The biconcave disk shape and deformability of mammalian RBCs rely on the membrane skeleton, a viscoelastic network of short, membrane-associated actin filaments (F-actin) cross-linked by long, flexible spectrin tetramers. Nonmuscle myosin II (NMII) motors exert force on diverse F-actin networks to control cell shapes,...
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.1718285115
更新日期:2018-05-08 00:00:00
abstract::The challenging problem of ultra-high-energy-density, high-efficiency, and small-scale portable power generation is addressed here using a distinctive thermophotovoltaic energy conversion mechanism and chip-based system design, which we name the microthermophotovoltaic (μTPV) generator. The approach is predicted to be...
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.1301004110
更新日期:2013-04-02 00:00:00
abstract::We describe a Kappa-on-Heavy (KoH) mouse that produces a class of highly diverse, fully human, antibody-like agents. This mouse was made by replacing the germline variable sequences of both the Ig heavy-chain (IgH) and Ig kappa (IgK) loci with the human IgK germline variable sequences, producing antibody-like molecule...
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.1901734117
更新日期:2020-01-07 00:00:00
abstract::Primary tumors secrete factors that alter the microenvironment of distant organs, rendering those organs as fertile soil for subsequent metastatic cancer cell colonization. Although the lungs are exposed to these factors ubiquitously, lung metastases usually develop as a series of discrete lesions. The underlining mol...
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.1100446108
更新日期:2011-03-01 00:00:00
abstract::From within an albino melanocyte line grown in vitro we identified and cloned cells that apparently had reverted to wild type. We sequenced a part of the tyrosinase gene, encompassing a candidate mutation, from wild-type, albino, and revertant cell DNAs. The revertant cells contain, on one chromosome, a perfect base r...
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.87.18.7010
更新日期:1990-09-01 00:00:00
abstract::Members of the caspase family of cysteine proteases play central roles in coordinating the stereotypical events that occur during apoptosis. Because the major executioner caspases, caspase-3 and caspase-7, exhibit almost indistinguishable activity toward certain synthetic peptide substrates, this has led to the widesp...
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.0707715105
更新日期:2008-09-02 00:00:00
abstract::The protein products of T4 bacteriophage genes 41, 43, 45, 44, and 62 have been purified to near homogeneity using an assay which measures their stimulation of DNA synthesis in a crude lysate of Escherichia coli cells in fected by an appropriate mutant phage. When all of these proteins and T4 gene 32 protein are incub...
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.72.12.4800
更新日期:1975-12-01 00:00:00
abstract::Recent single-molecule experiments reveal that mechanical tension on DNA can control both the speed and direction of the DNA polymerase motor. We present a theoretical description of this tension-induced "tuning" and "switching." The internal conformational states of the enzyme motor are represented as nodes, and the ...
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.1033134100
更新日期:2003-08-19 00:00:00
abstract::Protein framework alterations in heritable Cu, Zn superoxide dismutase (SOD) mutants cause misassembly and aggregation in cells affected by the motor neuron disease ALS. However, the mechanistic relationship between superoxide dismutase 1 (SOD1) mutations and human disease is controversial, with many hypotheses postul...
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.1308531111
更新日期:2014-10-28 00:00:00
abstract::A potential human footprint on Western Central African rainforests before the Common Era has become the focus of an ongoing controversy. Between 3,000 y ago and 2,000 y ago, regional pollen sequences indicate a replacement of mature rainforests by a forest-savannah mosaic including pioneer trees. Although some studies...
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.1715336115
更新日期:2018-03-27 00:00:00
abstract::Studies in animals demonstrate a crucial role for the amygdala in emotional and social behavior, especially as related to fear and aggression. Whereas lesion and functional-imaging studies in humans indicate the amygdala's participation in assessing the significance of nonverbal as well as paralinguistic cues, direct ...
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.96.18.10456
更新日期:1999-08-31 00:00:00
abstract::Inhibition of eicosanoid formation in larvae of the tobacco hornworm Manduca sexta, using specific inhibitors of phospholipase A2, cyclooxygenase, and lipoxygenase, severely weakened the ability of larvae to clear the bacterium Serratia marscescens from their hemolymph. The reduced capability to remove bacteria is ass...
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.88.3.1064
更新日期:1991-02-01 00:00:00
abstract::Early forms of the genetic code likely generated "statistical" proteins, with similar side chains occupying the same sequence positions at different ratios. In this scenario, groups of related side chains were treated by aminoacyl-tRNA synthetases as a single molecular species until a discrimination mechanism develope...
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.2136794100
更新日期:2003-12-23 00:00:00
abstract::The photoaffinity labeling agent 5-azidoindole-3-acetic acid, an analog of the endogenous plant hormone indole-3-acetic acid (an auxin), was used to identify indole-3-acetic acid-binding proteins in maize. Two peptides with subunit molecular masses of 24 and 22 kilodaltons are specifically labeled in a saturable manne...
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.86.16.6153
更新日期:1989-08-01 00:00:00
abstract::Alternative adaptations-different adaptive phenotypes maintained in the same life stage and the same population but not necessarily simultaneously expressed in the same individual-represent contrasting character sets produced by the same genome, in effect allowing a single species to occupy more than one sympatric nic...
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.83.5.1388
更新日期:1986-03-01 00:00:00
abstract::Primates can store sensory stimulus parameters in working memory for subsequent manipulation, but until now, there has been no demonstration of this capacity in rodents. Here we report tactile working memory in rats. Each stimulus is a vibration, generated as a series of velocity values sampled from a normal distribut...
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.1315171111
更新日期:2014-02-11 00:00:00
abstract::A general theory of the structure of complexes of the transition metals is developed on the basis of the enneacovalence of the metals and the requirements of the electroneutrality principle. An extra orbital may be provided through the small but not negligible amount of f and g character of spd bond orbitals, and an e...
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.74.12.5235
更新日期:1977-12-01 00:00:00
abstract::The density of benzodiazepine/gamma-aminobutyric acid receptor binding sites was lower in the midbrain of seizure-susceptible gerbils compared to control seizure-resistant gerbils. Binding of [3H]diazepam to high-affinity brain-specific sites in membrane homogenates of gerbil brain showed a 20-30% lower binding in mid...
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.82.19.6701
更新日期:1985-10-01 00:00:00
abstract::A plasmid construct expressing the p66 version of the human immunodeficiency virus reverse transcriptase as a bacterial fusion protein was subjected to in vitro mutagenesis, and the resulting variant proteins were assayed to define the locations of the two major enzymatic activities. The DNA polymerase activity was lo...
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.86.9.3104
更新日期:1989-05-01 00:00:00
abstract::A protein fraction from B. subtilis infected with phage SP01 (fraction LGG) stimulates the activity of RNA polymerase (EC 2.7.7.6; nucleosidetriphosphate:RNA nucleotidyltransferase) core from uninfected bacteria. Fraction LGG contains a protein (P-28, molecular weight 28,000) that is labeled after phage infection and ...
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.72.6.2366
更新日期:1975-06-01 00:00:00
abstract::Renal medullary cells contain high concentrations of myo-inositol, sorbitol, betaine, and glycerophosphocholine, whose levels vary with urinary osmolality. Accumulation of these "compatible" organic osmolytes is believed to help the cells osmoregulate in response to the high extracellular osmolality that occurs as par...
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.86.15.6002
更新日期:1989-08-01 00:00:00
abstract::Two genes have a synthetically lethal relationship when the silencing or inhibiting of 1 gene is only lethal in the context of a mutation or activation of the second gene. This situation offers an attractive therapeutic strategy, as inhibition of such a gene will only trigger cell death in tumor cells with an activate...
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.0901418106
更新日期:2009-08-04 00:00:00
abstract::Schiff bases of the diamines 1,3-diaminopropane, putrescine, and cadaverine and the polyamines spermidine and spermine with pyridoxal or pyridoxal phosphate occur in human urine, as shown by gas chromatographic/mass spectrometric selected ion-monitoring techniques. By use of synthetic standards, procedures were devise...
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.76.12.6652
更新日期:1979-12-01 00:00:00
abstract::The first crystal structure of the neurotransmitter/sodium symporter homolog LeuT revealed an occluded binding pocket containing leucine and 2 Na(+); later structures showed tricyclic antidepressants (TCAs) in an extracellular vestibule approximately 11 A above the bound leucine and 2 Na(+). We recently found this reg...
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.0811322106
更新日期:2009-04-07 00:00:00
abstract::AIDS remains incurable due to the permanent integration of HIV-1 into the host genome, imparting risk of viral reactivation even after antiretroviral therapy. New strategies are needed to ablate the viral genome from latently infected cells, because current methods are too inefficient and prone to adverse off-target e...
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.1405186111
更新日期:2014-08-05 00:00:00
abstract::The early detection of pathogens with epidemic potential is of major importance to public health. Most emerging infections result in dead-end "spillover" events in which a pathogen is transmitted from an animal reservoir to a human but is unable to achieve the sustained human-to-human transmission necessary for a full...
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.1521582113
更新日期:2016-04-12 00:00:00
abstract::In vivo, G protein-coupled receptors (GPCR) for neurotransmitters undergo complex intracellular trafficking that contribute to regulate their abundance at the cell surface. Here, we report a previously undescribed alteration in the subcellular localization of D1 dopamine receptor (D1R) that occurs in vivo in striatal ...
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.97.4.1879
更新日期:2000-02-15 00:00:00
abstract::The intracellular levels of many proteins are regulated by ubiquitin-dependent proteolysis. One of the best-characterized enzymes that catalyzes the attachment of ubiquitin to proteins is a ubiquitin ligase complex, Skp1-Cullin-F box complex containing Hrt1 (SCF). We sought to artificially target a protein to the SCF ...
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.141230798
更新日期:2001-07-17 00:00:00
abstract::l-Serine biosynthesis, a crucial metabolic process in most domains of life, is initiated by d-3-phosphoglycerate (d-3-PG) dehydrogenation, a thermodynamically unfavorable reaction catalyzed by d-3-PG dehydrogenase (SerA). d-2-Hydroxyglutarate (d-2-HG) is traditionally viewed as an abnormal metabolite associated with c...
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.1619034114
更新日期:2017-09-05 00:00:00