Abstract:
:A cyclic AMP-binding protein (CAP protein), cyclic AMP, and RNA polymerase holoenzyme are shown to initiate lac transcription at the lac promoter. Lac repressor appears to control transcription by preventing RNA polymerase and/or CAP protein from binding to the lac promoter. Results support the idea that the lac promoter is composed of two sites that interact with CAP protein and RNA polymerase holoenzyme. The promoter can be altered by mutation so that holoenzyme alone can initiate lac transcription correctly.
journal_name
Proc Natl Acad Sci U S Aauthors
Eron L,Block Rdoi
10.1073/pnas.68.8.1828subject
Has Abstractpub_date
1971-08-01 00:00:00pages
1828-32issue
8eissn
0027-8424issn
1091-6490journal_volume
68pub_type
杂志文章abstract::Males of the androdioecious species Caenorhabditis elegans are more likely to attempt to mate with and successfully inseminate C. elegans hermaphrodites that do not concurrently harbor sperm. Although a small number of genes have been implicated in this effect, the mechanism by which it arises remains unknown. In 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.1420439111
更新日期:2014-12-16 00:00:00
abstract::We identified cell surface markers associated with repression of p16(INK4a)/cyclin-dependent kinase inhibitor 2A(CDKN2A), a critical determinant in the acquisition of a plastic state. These cell surface markers allowed direct isolation of rare cells from healthy human breast tissue that exhibit extensive lineage plast...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 临床试验,杂志文章
doi:10.1073/pnas.1218682110
更新日期:2013-03-19 00:00:00
abstract::The relationship between performance and ability is a central concern in the social sciences: Are the most successful much more able than others, and are failures unskilled? Prior research has shown that noise and self-reinforcing dynamics make performance unpredictable and lead to a weak association between ability 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.1116048109
更新日期:2012-06-12 00:00:00
abstract::Equine arteritis virus (EAV) is a positive-strand RNA virus that uses a discontinuous transcription mechanism to generate a nested set of six subgenomic mRNAs from which its structural genes are expressed. A stable bacterial plasmid (pEAV030) containing a full-length cDNA copy of the 12.7-kb EAV genome was constructed...
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.94.3.991
更新日期:1997-02-04 00:00:00
abstract::In the mitochondrial genome of the hemichordate Balanoglossus carnosus, the codon AAA, which is assigned to lysine in most metazoans but to asparagine in echinoderms, is absent. Furthermore, the lysine tRNA gene carries an anticodon substitution that renders its gene product unable to decode AAA codons, whereas the as...
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.95.7.3703
更新日期:1998-03-31 00:00:00
abstract::Silicate melts at the top of the transition zone and the core-mantle boundary have significant influences on the dynamics and properties of Earth's interior. MgSiO3-rich silicate melts were among the primary components of the magma ocean and thus played essential roles in the chemical differentiation of the early Eart...
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.0802667105
更新日期:2008-06-10 00:00:00
abstract::Saccharopolyspora erythraea makes erythromycin, an antibiotic commonly used in human medicine. Unusually, the erythromycin biosynthetic (ery) cluster lacks a pathway-specific regulatory gene. We isolated a transcriptional regulator of the ery biosynthetic genes from S. erythraea and found that this protein appears to ...
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.0803622105
更新日期:2008-08-12 00:00:00
abstract::The secreted Bv8 protein has been recently characterized as a regulator of myeloid cell mobilization and a neutrophil-derived mediator of tumor angiogenesis in several xenografts, but its role in tumor progression in an endogenous setting was unknown. The rat insulin promoter (RIP)-T-antigen (Tag) is a well characteri...
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.0712185105
更新日期:2008-02-19 00:00:00
abstract::The synaptic vesicle membrane protein synaptotagmin (tagmin) is essential for fast, calcium-dependent, neurotransmitter release and is likely to be the calcium sensor for exocytosis, because of its many calcium-dependent properties. Polyphosphoinositides are needed for exocytosis, but it has not been known why. We now...
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.93.23.13327
更新日期:1996-11-12 00:00:00
abstract::Although geophysical observations of mantle regions that suggest the presence of partial melt have often been interpreted in light of the properties of basaltic liquids erupted at the surface, the seismic and rheological consequences of partial melting in the upper mantle depend instead on the properties of interstiti...
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.2014519117
更新日期:2020-09-08 00:00:00
abstract::Pancreatic ductal adenocarcinoma (PDAC) cells (PCC) have an exceptional propensity to metastasize early into intratumoral, chemokine-secreting nerves. However, we hypothesized the opposite process, that precancerous pancreatic cells secrete chemokines that chemoattract Schwann cells (SC) of nerves and thus induce read...
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.1606909114
更新日期:2017-01-03 00:00:00
abstract::With the increased popularity of zebrafish (Danio rerio) for mutagenesis studies, efficient methods for manipulation of its genome are needed. One approach is the use of a transposable element as a vector for gene transfer in this species. We report here the transformation of zebrafish and germ-line transmission of th...
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.95.9.5182
更新日期:1998-04-28 00:00:00
abstract::Drug resistance testing has been shown to be beneficial for clinical management of HIV type 1 infected patients. Whereas phenotypic assays directly measure drug resistance, the commonly used genotypic assays provide only indirect evidence of drug resistance, the major challenge being the interpretation of the 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.112177799
更新日期:2002-06-11 00:00:00
abstract::Aotus monkeys, which are generally killed when infected with the human malaria parasite Plasmodium falciparum, have been identified and grouped by karyotype. These animals were immunized with parasite material obtained from P. falciparum cultivated in vitro which had been maintained in culture for over a year. When su...
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.75.11.5665
更新日期:1978-11-01 00:00:00
abstract::We applied the directional tag PCR subtractive hybridization method to construct a rat hypothalamic cDNA library from which cerebellar and hippocampal sequences had been depleted, enriching 20-30-fold for sequences expressed selectively in the hypothalamus. We studied a sample of 94 clones selected for enrichment in 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.93.16.8733
更新日期:1996-08-06 00:00:00
abstract::Active immunization using tumor antigen-loaded dendritic cells holds promise for the adjuvant treatment of cancer to eradicate or control residual disease, but so far, most dendritic cell trials have been performed in end-stage cancer patients with high tumor loads. Here, in a phase I/II trial, we investigated the eff...
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.1008051107
更新日期:2010-08-03 00:00:00
abstract::Insertion of foreign DNA into an established mammalian genome can extensively alter the patterns of cellular DNA methylation. Adenovirus type 12 (Ad12)-transformed hamster cells, Ad12-induced hamster tumor cells, or hamster cells carrying integrated DNA of bacteriophage lambda were used as model systems. DNA methylati...
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.92.12.5515
更新日期:1995-06-06 00:00:00
abstract::The species-area relationship (SAR) gives a quantitative description of the increasing number of species in a community with increasing area of habitat. In conservation, SARs have been used to predict the number of extinctions when the area of habitat is reduced. Such predictions are most needed for landscapes rather ...
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.1311491110
更新日期:2013-07-30 00:00:00
abstract::Cryopreservation is widely used to maintain backups of cells as it enables the semipermanent storage of cells. During the freezing process, ice crystals that are generated inside and outside the cells can lethally damage the cells. All conventional cryopreservation methods use at least one cryoprotective agent (CPA) 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.1808645116
更新日期:2019-04-16 00:00:00
abstract::Dynein is a microtubule motor that powers motility of cilia and flagella. There is evidence that the relative sliding of the doublet microtubules is due to a conformational change in the motor domain that moves a microtubule bound to the end of an extension known as the stalk. A predominant model for the movement invo...
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.0808194105
更新日期:2008-12-16 00:00:00
abstract::Activated thiol-Sepharose [agarose-(glutathione-2-pyridyl disulfide) conjugate] has been used to immobilize proteins with a single or a few thiol groups via disulfide bridges. The immobilized proteins were subsequently proteolytically degraded. After washing, the thiol-containing peptides were eluted with a reducing 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.72.8.3029
更新日期:1975-08-01 00:00:00
abstract::The effect of fluctuations in rate constants on the kinetic behavior of cyclic reacting systems, caused by a fluctuating external parameter, is studied. It is shown (i) that the stochastic properties of the system can be analyzed analytically by using the usual master equation approach when the external parameter is f...
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.84.3.729
更新日期:1987-02-01 00:00:00
abstract::Clinical research should conform to high standards of ethical and scientific integrity, given that human lives are at stake. However, economic incentives can generate conflicts of interest for investigators, who may be inclined to withhold unfavorable results or even tamper with data in order to achieve desired outcom...
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.1919906117
更新日期:2020-06-16 00:00:00
abstract::NRSF/REST is a protein that silences transcription of a number of genes that contain a DNA element called the neuron-restrictive silencer element (NRSE). During embryogenesis, REST is expressed ubiquitously in nonneural cells, but is down-regulated during differentiation of neural progenitors into neurons. REST is als...
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.050578797
更新日期:2000-02-29 00:00:00
abstract::The image that best expresses Darwin's thinking is the tree of life. However, Darwin's human evolutionary tree lacked almost everything because only the Neanderthals were known at the time and they were considered one extreme expression of our own species. Darwin believed that the root of the human tree was very deep ...
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.0914614107
更新日期:2010-05-11 00:00:00
abstract::The integrity of cell membranes is maintained by a balance between the amount of cholesterol and the amounts of unsaturated and saturated fatty acids in phospholipids. This balance is maintained by membrane-bound transcription factors called sterol regulatory element-binding proteins (SREBPs) that activate genes encod...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
doi:10.1073/pnas.96.20.11041
更新日期:1999-09-28 00:00:00
abstract::Mice lacking major histocompatibility complex (MHC) antigens were generated by mating beta 2-microglobulin-deficient, and therefore class I-deficient, animals with MHC class II-deficient animals. When housed under sterile conditions, the resulting MHC-deficient mice appear healthy, survive for many months, and breed 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.90.9.3913
更新日期:1993-05-01 00:00:00
abstract::Methods to accurately predict potential drug target mutations in response to early-stage leads could drive the design of more resilient first generation drug candidates. In this study, a structure-based protein design algorithm (K* in the OSPREY suite) was used to prospectively identify single-nucleotide polymorphisms...
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.1411548112
更新日期:2015-01-20 00:00:00
abstract::Preliminary x-ray diffraction data from single crystals of the MoFe proteins of nitrogenase from Clostridium pasteurianum and Azotobacter vinelandii have been obtained. Both protein crystals belong to the P2(1) space group. The MoFe protein crystals from C. pasteurianum and A. vinelandii diffract to angles correspondi...
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.79.2.378
更新日期:1982-01-01 00:00:00
abstract::Tumor-specific molecules are needed across diverse areas of oncology for use in early detection, diagnosis, prognosis and therapy. Large and growing public databases of transcriptome sequencing data (RNA-seq) derived from tumors and normal tissues hold the potential of yielding tumor-specific molecules, but because th...
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.1508057112
更新日期:2015-06-09 00:00:00