Open complex scrunching before nucleotide addition accounts for the unusual transcription start site of E. coli ribosomal RNA promoters.

abstract：:The crystal structure of the murine Fab S-20-4 from a protective anti-cholera Ab specific for the lipopolysaccharide Ag of the Ogawa serotype has been determined in its unliganded form and in complex with synthetic fragments of the Ogawa O-specific polysaccharide (O-SP). The upstream terminal O-SP monosaccharide is sh...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Villeneuve S,Souchon H,Riottot MM,Mazie JC,Lei P,Glaudemans CP,Kovác P,Fournier JM,Alzari PM

更新日期：2000-07-18 00:00:00

abstract：:The structural and functional organization of the cell nucleus has been investigated using three-dimensional reconstruction, immunoelectron microscopy, and high-resolution in situ autoradiography. Nuclear regions enriched in small nuclear ribonucleoprotein particles (snRNPs) form a reticular network within the nucleop...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Spector DL

更新日期：1990-01-01 00:00:00

abstract：:Whether and how human populations exposed to the agricultural revolution are still affected by Darwinian selection remains controversial among social scientists, biologists, and the general public. Although methods of studying selection in natural populations are well established, our understanding of selection in hum...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Courtiol A,Pettay JE,Jokela M,Rotkirch A,Lummaa V

更新日期：2012-05-22 00:00:00

abstract：:Humans have altered natural patterns of fire for millennia, but the impact of human-set fires is thought to have been slight in wet closed-canopy forests. In the South Island of New Zealand, Polynesians (Māori), who arrived 700-800 calibrated years (cal y) ago, and then Europeans, who settled ∼150 cal y ago, used fire...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： McWethy DB,Whitlock C,Wilmshurst JM,McGlone MS,Fromont M,Li X,Dieffenbacher-Krall A,Hobbs WO,Fritz SC,Cook ER

更新日期：2010-12-14 00:00:00

abstract：:Biological carbon fixation is limited by the supply of Fe in vast regions of the global ocean. Dissolved Fe in seawater is primarily sourced from continental mineral dust, submarine hydrothermalism, and sediment dissolution along continental margins. However, the relative contributions of these three sources to the Fe...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Horner TJ,Williams HM,Hein JR,Saito MA,Burton KW,Halliday AN,Nielsen SG

更新日期：2015-02-03 00:00:00

abstract：:Infected cell protein 0 (ICP0) is a 775-residue multifunctional herpes simplex virus protein associated with numerous functions related to transactivation of gene expression and repression of host defenses to infection. We report that an uncharted domain of ICP0 located between residues 245 and 510 contains multiple S...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Liang Y,Kurakin A,Roizman B

更新日期：2005-04-19 00:00:00

abstract：:Social decisions require evaluation of costs and benefits to oneself and others. Long associated with emotion and vigilance, the amygdala has recently been implicated in both decision-making and social behavior. The amygdala signals reward and punishment, as well as facial expressions and the gaze of others. Amygdala ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Chang SW,Fagan NA,Toda K,Utevsky AV,Pearson JM,Platt ML

更新日期：2015-12-29 00:00:00

abstract：:Gamma-band synchronization adjusts the timing of excitatory and inhibitory inputs to a neuron. Neurons in the visual cortex are selective for stimulus orientation because of dynamic interactions between excitatory and inhibitory inputs. We hypothesized that these interactions and hence also orientation selectivity var...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Womelsdorf T,Lima B,Vinck M,Oostenveld R,Singer W,Neuenschwander S,Fries P

更新日期：2012-03-13 00:00:00

abstract：:Message passing is a fundamental technique for performing calculations on networks and graphs with applications in physics, computer science, statistics, and machine learning, including Bayesian inference, spin models, satisfiability, graph partitioning, network epidemiology, and the calculation of matrix eigenvalues....

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Cantwell GT,Newman MEJ

更新日期：2019-11-19 00:00:00

abstract：:Psychostimulant use is an ever-increasing socioeconomic burden, including a dramatic rise during pregnancy. Nevertheless, brain-wide effects of psychostimulant exposure are incompletely understood. Here, we performed Fos-CreERT2-based activity mapping, correlated for pregnant mouse dams and their fetuses with amphetam...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Fuzik J,Rehman S,Girach F,Miklosi AG,Korchynska S,Arque G,Romanov RA,Hanics J,Wagner L,Meletis K,Yanagawa Y,Kovacs GG,Alpár A,Hökfelt TGM,Harkany T

更新日期：2019-12-17 00:00:00

abstract：:Entropic effects have often been invoked to explain the extraordinary catalytic power of enzymes. In particular, the hypothesis that enzymes can use part of the substrate-binding free energy to reduce the entropic penalty associated with the subsequent chemical transformation has been very influential. The enzymatic r...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kazemi M,Himo F,Åqvist J

更新日期：2016-03-01 00:00:00

abstract：:Amputation of the zebrafish caudal fin stimulates regeneration of the dermal skeleton and reexpression of sonic hedgehog (shh)-signaling pathway genes. Expression patterns suggest a role for shh signaling in the secretion and patterning of the regenerating dermal bone, but a direct role has not been demonstrated. We e...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Quint E,Smith A,Avaron F,Laforest L,Miles J,Gaffield W,Akimenko MA

更新日期：2002-06-25 00:00:00

abstract：:Experimental observations of unexpected shear rigidity in confined liquids, on very low frequency scales on the order of 0.01 to 0.1 Hz, call into question our basic understanding of the elasticity of liquids and have posed a challenge to theoretical models of the liquid state ever since. Here we combine the nonaffine...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Zaccone A,Trachenko K

更新日期：2020-08-18 00:00:00

abstract：:Transgenic mice harboring the int-2/Fgf-3 protooncogene under transcriptional control of the mouse mammary tumor virus (MMTV) promoter/enhancer exhibit a dramatic, benign hyperplasia of the mammary gland. In one int-2 transgenic line (TG.NX), this growth disturbance is evoked by pregnancy and regresses after parturiti...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Lee FS,Lane TF,Kuo A,Shackleford GM,Leder P

更新日期：1995-03-14 00:00:00

abstract：:Working memory (WM) is the ability to retain and associate information over brief time intervals. Functional imaging studies demonstrate that WM is mediated by a distributed network including frontal and posterior cortices, hippocampus, and cerebellum. In rodents, the presentation of stimuli in a WM task is followed b...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Tesche CD,Karhu J

更新日期：2000-01-18 00:00:00

abstract：:Nerve growth factor (NGF) is a neurotrophin with the ability to exert specific effects on cells of the immune system. Human monocytes/macrophages (M/M) infected in vitro with HIV type 1 (HIV-1) are able to produce substantial levels of NGF that are associated with enhanced expression of the high-affinity NGF receptor ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Garaci E,Caroleo MC,Aloe L,Aquaro S,Piacentini M,Costa N,Amendola A,Micera A,Caliò R,Perno CF,Levi-Montalcini R

更新日期：1999-11-23 00:00:00

abstract：:Because of the insolubility and polymeric properties of amyloid fibrils, techniques used conventionally to analyze protein structure and dynamics have often been hampered. Ultrasonication can induce the monomeric solution of amyloidogenic proteins to form amyloid fibrils. However, ultrasonication can break down prefor...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Chatani E,Lee YH,Yagi H,Yoshimura Y,Naiki H,Goto Y

更新日期：2009-07-07 00:00:00

abstract：:Many bacterial pathogens produce diffusible signal factor (DSF)-type quorum sensing (QS) signals in modulation of virulence and biofilm formation. Previous work on Xanthomonas campestris showed that the RpfC/RpfG two-component system is involved in sensing and responding to DSF signals, but little is known in other mi...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Deng Y,Schmid N,Wang C,Wang J,Pessi G,Wu D,Lee J,Aguilar C,Ahrens CH,Chang C,Song H,Eberl L,Zhang LH

更新日期：2012-09-18 00:00:00

abstract：:A nonselective ex vivo assay was used to directly detect and quantify zidovudine (AZT)-resistant human immunodeficiency virus type 1 (HIV-1) in the blood of treated and untreated patients. In contrast to previous reports, drug-resistant virus was detected in peripheral blood mononuclear cells of a few of the patients ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Mohri H,Singh MK,Ching WT,Ho DD

更新日期：1993-01-01 00:00:00

abstract：:The properties of the virus synthesized by each of three morphologically different cell lines originating from DBA/2J fetal liver cells transformed by the anemic strain of Friend leukemia virus in vitro were analyzed. The cells of line G-1 are malignant in syngeneic DBA/2 mice, grow in suspension, and are erythroid in...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Tsuei D,Pogo BG,Friend C

更新日期：1980-10-01 00:00:00

abstract：:Many substances in the plant kingdom and in man's diet occur as glycosides. Recent studies have indicated that many glycosides that are not mutagenic in tests such as the Salmonella test become mutagenic upon hydrolysis of the glycosidic linkages. The Salmonella test utilizes a liver homogenate to approximate mammalia...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Tamura G,Gold C,Ferro-Luzzi A,Ames BN

更新日期：1980-08-01 00:00:00

abstract：:Ischemia of the myocardium and lower limbs is a common consequence of arterial disease and a major source of morbidity and mortality in modernized countries. Inducing neovascularization for the treatment of ischemia is an appealing therapeutic strategy for patients for whom traditional treatment modalities cannot be p...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Jang E,Albadawi H,Watkins MT,Edelman ER,Baker AB

更新日期：2012-01-31 00:00:00

abstract：:Mutant phenotype analysis of bacteria has been revolutionized by genome-scale screening procedures, but essential genes have been left out of such studies because mutants are missing from the libraries analyzed. Since essential genes control the most fundamental processes of bacterial life, this is a glaring deficienc...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gallagher LA,Bailey J,Manoil C

更新日期：2020-07-28 00:00:00

abstract：:The HB-19 pseudopeptide 5[Kpsi(CH(2)N)PR]-TASP, psi(CH(2)N) for reduced peptide bond, is a specific inhibitor of HIV infection in different CD4(+) cell lines and in primary T-lymphocytes and macrophages. It blocks virus-particle attachment to permissive cells by binding and forming a stable complex with nucleolin expr...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Krust B,Vienet R,Cardona A,Rougeot C,Jacotot E,Callebaut C,Guichard G,Briand JP,Grognet JM,Hovanessian AG,Edelman L

更新日期：2001-11-20 00:00:00

abstract：:Phytochrome is the photoreceptor that controls red light-mediated morphogenesis in higher plants. It exists in two photointerconvertible forms, a red light-absorbing form, Pr, and a far-red light-absorbing form, Pfr. Because photoconversion of Pr to Pfr by a brief light pulse decreases the in vivo half-life of this ch...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Shanklin J,Jabben M,Vierstra RD

更新日期：1987-01-01 00:00:00

abstract：:Critical to the maintenance of circadian rhythmicity is the cyclic expression of at least some components of the central oscillator. High-amplitude cycling of mRNA and protein abundance, protein phosphorylation and nuclear/cytoplasmic shuttling have all been implicated in the maintenance of circadian period. Here we u...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kim WY,Geng R,Somers DE

更新日期：2003-04-15 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

authors： Chng C,Lum AM,Vroom JA,Kao CM

更新日期：2008-08-12 00:00:00

abstract：:We identify a gene, organ boundary1 (OBO1), by its unique pattern of enhancer- driven GFP expression at the boundaries between the apical meristems and lateral organs in Arabidopsis embryos, seedlings, and mature plants. OBO1 also is expressed at the root apical meristem and in distinct cell files surrounding this are...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Cho E,Zambryski PC

更新日期：2011-02-01 00:00:00

abstract：:Molecular dynamics (MD) simulations provide essential information about the thermodynamics and dynamics of proteins. To construct the free-energy surface from equilibrium trajectories, it is necessary to group the individual snapshots in a meaningful way. The inherent structures (IS) are shown to provide an appropriat...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Rao F,Karplus M

更新日期：2010-05-18 00:00:00

abstract：:The envelope spike of HIV is one of the most highly N-glycosylated structures found in nature. However, despite extensive research revealing essential functional roles in infection and immune evasion, the chemical structures of the glycans on the native viral envelope glycoprotein gp120--as opposed to recombinantly ge...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Doores KJ,Bonomelli C,Harvey DJ,Vasiljevic S,Dwek RA,Burton DR,Crispin M,Scanlan CN

更新日期：2010-08-03 00:00:00