Abstract:
:The high resolution 1H and 31P NMR spectra of the (dG-dC)8 duplex have been recorded in low- and high-salt solutions in order to evaluate the structural aspects of the salt-induced transition of oligo(dG-dC) in solution [Pohl, F. M. & Jovin, T. M. (1972) J. Mol. Biol. 67, 375-396]. The NMR data require that the (dG-dC)8 duplex in 4 M NaCl adopt an "alternating B-DNA" conformation for which the symmetry unit repeats every two base pairs. By contrast, the oligomer duplex in low-salt solution is of the regular B-DNA type in solution. The chemical shift parameters for oligo(dG-dC) in high-salt solution demonstrate that every other glycosidic torsion angle and phosphodiester linkage adopts a different conformation from that observed in regular B-DNA. We demonstrate further that the generation of the "alternating B-DNA" structure is facilitated by introduction of halogen atoms at the 5 position of pyrimidine and that this probably reflects the greater overlap of this position with adjacent base pairs in high salt solution. An "alternating B-DNA" model has recently been proposed for alternating deoxy purine-deoxy pyrimidine polynucleotides based on the x-ray structure of pdA-dT-dA-dT [Klug, A., Jack, A., Viswamitra, M.A., Kennard, O., Shakked, Z. & Steitz, T.A. (1979) J. Mol. Biol., in press].
journal_name
Proc Natl Acad Sci U S Aauthors
Patel DJ,Canuel LL,Pohl FMdoi
10.1073/pnas.76.6.2508subject
Has Abstractpub_date
1979-06-01 00:00:00pages
2508-11issue
6eissn
0027-8424issn
1091-6490journal_volume
76pub_type
杂志文章abstract::Over the past five decades, ultra high vacuum (uhv) techniques applied to well-defined single-crystal samples (the "surface science paradigm") have transformed our understanding of fundamental surface chemistry. To translate this success to the world of realistic heterogeneous catalysis, however, requires one seriousl...
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.1006634107
更新日期:2011-01-18 00:00:00
abstract::Invasive potentials of carcinomas greatly contribute to their metastasis, which is a major threat in most cancers. We have recently shown that Arf6 plays a pivotal role in breast cancer invasive activities and identified AMAP1 as an effector of GTP-Arf6 in invasion. Expression of AMAP1 correlates well with invasive ph...
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.0509166103
更新日期:2006-05-02 00:00:00
abstract::Cell signaling systems sense and respond to ligands that bind cell surface receptors. These systems often respond to changes in the concentration of extracellular ligand more rapidly than the ligand equilibrates with its receptor. We demonstrate, by modeling and experiment, a general "systems level" mechanism cells us...
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.1322761111
更新日期:2014-09-16 00:00:00
abstract::The Arctic Ocean already experiences areas of low pH and high CO2, and it is expected to be most rapidly affected by future ocean acidification (OA). Copepods comprise the dominant Arctic zooplankton; hence, their responses to OA have important implications for Arctic ecosystems, yet there is little data on their curr...
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.1315162110
更新日期:2013-12-17 00:00:00
abstract::Infection by certain human papillomavirus types is regarded as the major risk factor in the development of cervical cancer, one of the most common cancers of women worldwide. Analysis of the immunogenic and structural features of papillomavirus virions has been hampered by the inability to efficiently propagate the vi...
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.89.24.12180
更新日期:1992-12-15 00:00:00
abstract::Brief learning experience (classical conditioning) induces frequency-specific receptive-field (RF) plasticity in the auditory cortex, characterized as increased response to the frequency of the conditioned stimulus and decreased responses to most other frequencies, including the pretraining best frequency. This experi...
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.90.6.2394
更新日期:1993-03-15 00:00:00
abstract::Evolutionary processes leading to adaptive radiation regularly occur too fast to be accurately recorded in the fossil record but too slowly to be readily observed in living biota. The study of evolutionary radiations is thereby confronted with an epistemological gap between the timescales and approaches used by neonto...
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.1308588110
更新日期:2013-08-20 00:00:00
abstract::Strong, short-ranged positional correlations involving counterions can induce a net attractive force between negatively charged strands of DNA and lead to the formation of ion pairs in dilute ionic solutions. However, the long range of the Coulomb interactions impedes the development of a simple local picture. We addr...
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.0600282103
更新日期:2006-05-16 00:00:00
abstract::Lineage plasticity is a prominent feature of pancreatic ductal adenocarcinoma (PDA) cells, which can occur via deregulation of lineage-specifying transcription factors. Here, we show that the zinc finger protein ZBED2 is aberrantly expressed in PDA and alters tumor cell identity in this disease. Unexpectedly, our epig...
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.1921484117
更新日期:2020-05-26 00:00:00
abstract::We report measurements of the geometrical structure and temporal evolution of metastable helical intermediates in the pathway for cholesterol crystallization in native and model biles. We find that the lecithin component in the bile can dramatically affect the kinetics along this pathway. We also present a theoretical...
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.90.23.11341
更新日期:1993-12-01 00:00:00
abstract::Sprouty proteins act as intracellular inhibitors of receptor tyrosine kinase signaling. Here we show that the mammalian Sprouty2 protein contains an iron-sulfur complex that can exist in an oxidized, reduced, or nitrosylated state. Purified Sprouty2 assembles into large monodisperse spheres containing approximately 24...
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.0506714102
更新日期:2005-09-27 00:00:00
abstract::Uropathogenic Escherichia coli invade bladder epithelial cells (BECs) by direct entry into specialized cAMP regulated exocytic compartments. Remarkably, a significant number of these intracellular bacteria are subsequently expelled in a nonlytic and piecemeal fashion by infected BECs. Here, we report that expulsion of...
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.0900527106
更新日期:2009-09-01 00:00:00
abstract::Understanding the factors that shape macroevolutionary patterns in functional traits is a central goal of evolutionary biology. Alternative strategies of sexual reproduction (inbreeding vs. outcrossing) have divergent effects on population genetic structure and could thereby broadly influence trait evolution. However,...
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.1213867110
更新日期:2013-03-05 00:00:00
abstract::We have applied a molecular biology approach to the identification of human monoclonal antibodies. Human peripheral blood lymphocyte mRNA was converted to cDNA and a select subset was amplified by the polymerase chain reaction. These products, containing coding sequences for numerous immunoglobulin heavy- and kappa li...
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.87.20.8095
更新日期:1990-10-01 00:00:00
abstract::Magnetotactic bacteria synthesize highly uniform intracellular magnetite nanoparticles through the action of several key biomineralization proteins. These proteins are present in a unique lipid-bound organelle (the magnetosome) that functions as a nanosized reactor in which the particle is formed. A master regulator p...
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.1409256111
更新日期:2014-11-11 00:00:00
abstract::A temperature-sensitive ras allele has an effective lethal phase at 29 degrees C about 12 hr after pupation and a temperature-sensitive period for lethality beginning midway through the third larval instar and ending around pupation. The mutation also alters the quantity of pteridines present in the eyes, testes, 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.67.3.1101
更新日期:1970-11-01 00:00:00
abstract::Volume changes associated with protein folding reactions contain valuable information about the folding mechanism and the nature of the transition state. However, meaningful interpretation of such data requires that overall volume changes be deconvoluted into individual contributions from different structural componen...
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.1317973110
更新日期:2013-12-24 00:00:00
abstract::Cedar virus (CedV) is a bat-borne henipavirus related to Nipah virus (NiV) and Hendra virus (HeV), zoonotic agents of fatal human disease. CedV receptor-binding protein (G) shares only ∼30% sequence identity with those of NiV and HeV, although they can all use ephrin-B2 as an entry receptor. We demonstrate that CedV 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.1911773116
更新日期:2019-10-08 00:00:00
abstract::A cloned segment of yeast DNA containing the structural gene for imidazoleglycerolphosphate dehydratase (D-erythro-imidazoleglycerolphosphate hydro-lase, EC 4.2.1.19) is transcribed and translated in Escherichia coli with sufficient fidelity to produce functional enzyme. This segment of yeast DNA was isolated as a via...
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.74.12.5255
更新日期:1977-12-01 00:00:00
abstract::ALS is a terminal disease of motor neurons that is characterized by accumulation of proteinaceous deposits in affected cells. Pathological deposition of mutated Cu/Zn superoxide dismutase (SOD1) accounts for ∼20% of the familial ALS (fALS) cases. However, understanding the molecular link between mutation and disease h...
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.1320786110
更新日期:2014-01-07 00:00:00
abstract::We have found a soluble cyclase, using for assay radioactively marked ATP as precursor. The reaction product was isolated by thin-layer chromatography and identified by specific degradation. After homogenization, part of the activity remained in the particulate fraction but could be easily extracted. The cyclase was 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.63.1.86
更新日期:1969-05-01 00:00:00
abstract::By using a structure-based computer-assisted search, we have found a butyrophenone derivative that is a selective inhibitor of the human immunodeficiency virus 1 (HIV-1) protease. The computer program creates a negative image of the active site cavity using the crystal structure of the HIV-1 protease. This image was 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.87.17.6644
更新日期:1990-09-01 00:00:00
abstract::Gene expression in higher organisms is thought to be regulated by a complex network of transcription factor binding and chromatin modifications, yet the relative importance of these two factors remains a matter of debate. Here, we show that a computational approach allows surprisingly accurate prediction of histone mo...
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.1412081111
更新日期:2014-09-16 00:00:00
abstract::A 90-kDa surface glycoprotein was previously isolated and shown to be required for infection by the "major" group of human rhinovirus (HRV) serotypes. In the present work, the amino acid sequence of the receptor protein was obtained from CNBr and tryptic peptides. Using degenerate oligonucleotides predicted from the p...
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.86.13.4907
更新日期:1989-07-01 00:00:00
abstract::Nanoparticles are increasingly used in various fields, including biomedicine and electronics. One application utilizes the opacifying effect of nano-TiO(2), which is frequently used as pigment in cosmetics. Although TiO(2) is believed to be biologically inert, an emerging literature reports increased incidence of resp...
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.1008155107
更新日期:2010-11-09 00:00:00
abstract::Small GTP-binding proteins play a critical role in the regulation of a range of cellular processes--including growth, differentiation, and intracellular transportation. Previously, we isolated a gene, rgp1, encoding a small GTP-binding protein, by differential screening of a rice cDNA library with probe DNAs from rice...
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.92.10.4138
更新日期:1995-05-09 00:00:00
abstract::DNA "breathing" is a thermally driven process in which base-paired DNA sequences transiently adopt local conformations that depart from their most stable structures. Polymerases and other proteins of genome expression require access to single-stranded DNA coding templates located in the double-stranded DNA "interior,"...
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.1314862110
更新日期:2013-10-22 00:00:00
abstract::Photosynthesis has recently gained considerable attention for its potential role in the development of renewable energy sources. Optimizing photosynthetic organisms for biomass or biofuel production will therefore require a systems understanding of photosynthetic processes. We reconstructed a high-quality genome-scale...
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.1117907109
更新日期:2012-02-14 00:00:00
abstract::We have recently shown that p-terphenyl-3,5,3',5'-tetracarboxylic acid adsorbed on graphite self-assembles into a two-dimensional rhombus random tiling. This tiling is close to ideal, displaying long-range correlations punctuated by sparse localized tiling defects. In this article we explore the analogy between dynami...
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.0902443106
更新日期:2009-09-08 00:00:00
abstract::Helper-dependent adenoviral vectors deleted of all viral coding sequences have shown an excellent gene expression profile in a variety of animal models, as well as a reduced toxicity after systemic delivery. What is still unclear is whether long-term expression and therapeutic dosages of these vectors can be obtained ...
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.101122498
更新日期:2001-05-22 00:00:00