Abstract:
:Experiments were designed with the aim of understanding the mechanism whereby the lambda repressor inhibits messenger RNA synthesis. Complexes containing lambda DNA and RNA polymerase were isolated from repressed and derepressed lysogens and analyzed for the relative amounts of RNA polymerase per phage genome. The data indicate that the repressor inhibits the binding of RNA polymerase to promoter sites known to be under direct control of the repressor.
journal_name
Proc Natl Acad Sci U S Aauthors
Hayward WS,Green MHdoi
10.1073/pnas.64.3.962subject
Has Abstractpub_date
1969-11-01 00:00:00pages
962-9issue
3eissn
0027-8424issn
1091-6490journal_volume
64pub_type
杂志文章abstract::Electrically excitable cells harness voltage-coupled calcium influx to transmit intracellular signals, typically studied in neurons and cardiomyocytes. Despite intense study in higher organisms, investigations of voltage and calcium signaling in bacteria have lagged due to their small size and a lack of sensitive tool...
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.1703084114
更新日期:2017-08-29 00:00:00
abstract::Zif268, a zinc finger protein whose mRNA is rapidly activated in cells exposed to growth factors or other signaling agents, is thought to play a role in regulating the genetic program induced by extracellular ligands. We report that Zif268 has one of the characteristics of a transcriptional regulator, namely, sequence...
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.86.22.8737
更新日期:1989-11-01 00:00:00
abstract::The persistent tetrodotoxin (TTX)-sensitive sodium current, detected in neurons of many regions of mammalian brains, is associated with many essential neuronal activities, including boosting of excitatory synaptic inputs, acceleration of firing rates, and promotion of oscillatory neuronal activities. However, the orig...
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.0307695101
更新日期:2004-08-10 00:00:00
abstract::Two-dimensional gel electrophoresis of immunoprecipitated human HLA-DR antigens from cells expressing the HLA-DR4 haplotype shows distinct clustering of beta-chain patterns. Six unique electrophoretic variants were observed among 17 HLA-DR4 homozygous cell lines (HCL) analyzed. These patterns correlate precisely with ...
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.80.22.6962
更新日期:1983-11-01 00:00:00
abstract::We have determined the localization and orientation of two genetic probes within the human major histocompatibility complex by chromosomal in situ hybridization. Our data indicate that a cloned genomic probe cross-hybridizing to HLA-A, -B, and -C heavy chain loci is homologous to sequences located on chromosome 6 at b...
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.81.9.2816
更新日期:1984-05-01 00:00:00
abstract::We have recently identified a family of rhesus monkeys with members exhibiting a spontaneous hypercholesterolemia associated with a low density lipoprotein receptor (LDLR) deficiency. By using the polymerase chain reaction, we now show that the affected monkeys are heterozygous for a nonsense mutation in exon 6 of 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.87.8.3122
更新日期:1990-04-01 00:00:00
abstract::Glyoxalase I forms part of the glyoxalase pathway that detoxifies reactive aldehydes such as methylglyoxal, using the spontaneously formed glutathione hemithioacetal as substrate. All known eukaryotic enzymes contain zinc as their metal cofactor, whereas the Escherichia coli glyoxalase I contains nickel. Database mini...
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.0402918101
更新日期:2004-09-07 00:00:00
abstract::We have previously observed the spontaneous, pH-dependent insertion of a water-soluble peptide to form a helix across lipid bilayers [Hunt, J. F., Rath, P., Rothschild, K. J. & Engelman, D. M. (1997) Biochemistry 36, 15177-15192]. We now use a related peptide, pH (low) insertion peptide, to translocate cargo molecules...
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.0601463103
更新日期:2006-04-25 00:00:00
abstract::Urbanization represents an extreme transformation of more natural systems. Populations of most species decline or disappear with urbanization, and yet some species persist and even thrive in cities. What determines which species persist or thrive in urban habitats? Direct competitive interactions among species can inf...
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.1809317115
更新日期:2018-12-04 00:00:00
abstract::A fundamental question in the study of human language acquisition centers around apportioning explanatory force between the experience of the learner and the core knowledge that allows learners to represent that experience. We provide a previously unidentified kind of data identifying children's contribution to langua...
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.1517094113
更新日期:2016-01-26 00:00:00
abstract::The field of perceptual learning has identified changes in perceptual templates as a powerful mechanism mediating the learning of statistical regularities in our environment. By measuring threshold-vs.-contrast curves using an orientation identification task under varying levels of external noise, the perceptual templ...
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.1417056111
更新日期:2014-11-25 00:00:00
abstract::Both plants and animals require the activity of proteins containing nucleotide binding (NB) domain and leucine-rich repeat (LRR) domains for proper immune system function. NB-LRR proteins in plants (NLR proteins in animals) also require conserved regulation via the proteins SGT1 and cytosolic HSP90. RAR1, a protein 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.0904877106
更新日期:2009-06-16 00:00:00
abstract::We previously demonstrated that platelets express high levels of the tyrosine protein kinase pp60c-src. By a quantitative immunoblot assay, it is shown in this report that pp60c-src represents 0.2-0.4% of total platelet protein. The expression of high levels of pp60c-src in platelets correlated with high levels of tot...
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.86.3.901
更新日期:1989-02-01 00:00:00
abstract::Cumulative distributions of the number of doublings undergone by mixed megakaryocytic/erythroblastic colonies and by pure megakaryocytic colonies were determined from plasma clot cultures of bone marrow (from C57BL/6 mice) supplemented with erythropoietin. Analysis of these distributions suggests that these colonies 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.79.14.4410
更新日期:1982-07-01 00:00:00
abstract::Developmental genetic studies of evolved differences in morphology have led to the hypothesis that cis-regulatory changes often underlie morphological evolution. However, because most of these studies focus on evolved loss of traits, the genetic architecture and possible association with cis-regulatory changes of gain...
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.1407567111
更新日期:2014-09-23 00:00:00
abstract::Plasma membrane fractions from Xenopus laevis oocytes were incorporated into planar lipid bilayers. We show the existence of numerous Ca2+-activated nonspecific channels that are more permeable to anions. These channels are activated by Ca2+ at micromolar concentration but not by Mg2+, Zn2+, or Mn2+, even at millimola...
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.81.16.5155
更新日期:1984-08-01 00:00:00
abstract::Experiments were performed to ascertain the degree to which the amount of amino acids might be one of the regulatory factors that control the activity of the nucleolar RNA polymerase. Assays of the enzymatic activity were done with isolated nuclei from cells incubated with low and high concentrations of amino acids. 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.68.12.3040
更新日期:1971-12-01 00:00:00
abstract::Purified preparations of rabbit skeletal white, red, and cardiac muscle myosin (WM, RM, and CM) were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Significant differences in both the molecular weights and number of light chains in these myosins were found. WM has three distinct light-chain co...
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.68.5.946
更新日期:1971-05-01 00:00:00
abstract::UDPglucuronosyltransferase [UDPglucuronate beta-D-glucuronosyltransferase (acceptor-unspecific), EC 2.4.1.17] is a group of enzymes with distinct but partially overlapping substrate specificity. A rabbit antiserum raised against one purified rat liver UDPglycuronosyltransferase isoform was specific for UDPglucuronosyl...
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.82.9.2990
更新日期:1985-05-01 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::Mutualisms between fungi and fungus-growing animals are model systems for studying coevolution and complex interactions between species. Fungal growing behavior has enabled cultivating animals to rise to major ecological importance, but evolution of farming symbioses is thought to be restricted to three terrestrial 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.2535227100
更新日期:2003-12-23 00:00:00
abstract::Antischizophrenic neuroleptic drugs of the diphenylbutylpiperidine class, which includes pimozide, fluspirilene, penfluridol, and clopimozide, inhibit [3H]nitrendipine binding with IC50 values of 13-30 nM. This inhibition involves receptors for the verapamil/prenylamine class of calcium channel antagonists. These diph...
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.80.16.5122
更新日期:1983-08-01 00:00:00
abstract::Regulation of irreversible cell lineage commitment depends on a delicate balance between positive and negative regulators, which comprise a sophisticated network of transcription factors. Receptor activator of NF-kappaB ligand (RANKL) stimulates the differentiation of bone-resorbing osteoclasts through the induction o...
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.0912779107
更新日期:2010-02-16 00:00:00
abstract::An approach combining signal detection theory and precise 3D reconstructions from serial section electron microscopy (3DEM) was used to investigate synaptic plasticity and information storage capacity at medial perforant path synapses in adult hippocampal dentate gyrus in vivo. Induction of long-term potentiation (LTP...
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.1716189115
更新日期:2018-03-06 00:00:00
abstract::The interactions between cancer cells and the surrounding host stromal tissue play a critical role in tumor progression and metastasis, but the molecular nature of this relationship remains largely uncharacterized. Furthermore, although genetic changes of neoplastic cells in tumors contribute significantly to tumor pr...
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.0609635104
更新日期:2006-12-26 00:00:00
abstract::We have established empirical limits for the circular dichroism spectra appropriate for aqueous solutions of the B, C, and A forms of calf-thymus DNA and have analyzed DNA conformations in biological structures. The circular dichroism spectrum above 250 nm of purified calf-thymus chromatin can be satisfactorily accoun...
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.69.11.3263
更新日期:1972-11-01 00:00:00
abstract::The DNA-binding protein CCCTC-binding factor (CTCF) and the cohesin complex function together to shape chromatin architecture in mammalian cells, but the molecular details of this process remain unclear. Here, we demonstrate that a 79-aa region within the CTCF N terminus is essential for cohesin positioning at CTCF bi...
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.1911708117
更新日期:2020-01-28 00:00:00
abstract::In Gram-negative bacteria, the outer membrane contains primarily β-barrel transmembrane proteins and lipoproteins. The insertion and assembly of β-barrel outer-membrane proteins (OMPs) is mediated by the β-barrel assembly machinery (BAM) complex, the core component of which is the 16-stranded transmembrane β-barrel Ba...
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.1722530115
更新日期:2018-08-21 00:00:00
abstract::Adult rats were trained to detect the occurrence of a two-element sound sequence in a background of nine other nontarget sound pairs. Training resulted in a modest, enduring, static expansion of the cortical areas of representation of both target stimulus sounds. More importantly, once the initial stimulus A in the ta...
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.1009433107
更新日期:2010-08-17 00:00:00
abstract::We describe a 98-base-pair region (-38 to +60) in the long terminal repeat of the Drosophila gypsy retrotransposon that is sufficient for accurate normal-level transcription. We find that, unlike most RNA polymerase II (pol II) promoters, the gypsy promoter includes downstream sequences that are required for full acti...
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.88.1.102
更新日期:1991-01-01 00:00:00