Crystallographic structure of a photoreceptor protein at 2.4 A resolution.

abstract：:In many of their compounds the transition metals have covalence 9, forming nine bonds with use of nine hybrid spd bond orbitals. A set of maximum-valence single-bond radii is formulated for use in these compounds. These radii are in reasonably good agreement with observed bond lengths. Quadruple bonds between two tran...

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

authors： Pauling L

更新日期：1975-10-01 00:00:00

abstract：:The transforming growth factors beta (TGF-beta s) are important modulators of growth and differentiation. They are intermolecular disulfide-bonded homodimeric molecules. The monomer fold has a conserved cystine knot and lacks a hydrophobic core. The biological specificity of a given member of the family is believed to...

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

authors： Venkataraman G,Sasisekharan V,Cooney CL,Langer R,Sasisekharan R

更新日期：1995-06-06 00:00:00

abstract：:We have previously shown that geographic differences in cancer mortalities in Europe are related to (in order of importance): geographic distances (reflecting environmental differences), ethnohistoric distances (encompassing cultural and genetic attributes), and genetic distances of the populations in the areas studie...

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

authors： Sokal RR,Oden NL,Rosenberg MS,Thomson BA

更新日期：2000-05-23 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

authors： Jarrell KA,Meselson M

更新日期：1991-01-01 00:00:00

abstract：:Rabbit chondrocyte cultures on plastic dishes are capable of depositing a cartilaginous matrix, although the matrix does not calcify unless high levels of phosphate are added to the medium. In the present study, we cultivated a pelleted mass of rabbit growth-plate chondrocytes in the presence of Eagle's minimum essent...

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

authors： Kato Y,Iwamoto M,Koike T,Suzuki F,Takano Y

更新日期：1988-12-01 00:00:00

abstract：:The poison frogs (family Dendrobatidae) are terrestrial anuran amphibians displaying a wide range of coloration and toxicity. These frogs generally have been considered to be aposematic, but relatively little research has been carried out to test the predictions of this hypothesis. Here we use a comparative approach t...

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

authors： Summers K,Clough ME

更新日期：2001-05-22 00:00:00

abstract：:Escherichia coli glutamine synthetase (GS) was inactivated by a nonenzymic mixed-function oxidation system composed of ascorbate, O2, and Fe(III). Partial inactivation of GS by this system leads to the formation of hybrid GS molecules (dodecamers) composed of both active and inactive subunits. Subunit interactions in ...

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

authors： Nakamura K,Stadtman ER

更新日期：1984-04-01 00:00:00

abstract：:Commonly considered strategies for reducing the environmental impact of light-duty transportation include using alternative fuels and improving vehicle fuel economy. We evaluate the air quality-related human health impacts of 10 such options, including the use of liquid biofuels, diesel, and compressed natural gas (CN...

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

authors： Tessum CW,Hill JD,Marshall JD

更新日期：2014-12-30 00:00:00

abstract：:Ribosome crystal structures have revealed that two small subunit proteins, S9 and S13, have C-terminal tails, which, together with several features of 16S rRNA, contact the anticodon stem-loop of P-site tRNA. To test the functional importance of these protein tails, we created genomic deletions of the C-terminal regio...

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

authors： Hoang L,Fredrick K,Noller HF

更新日期：2004-08-24 00:00:00

abstract：:Tumor hypoxia reduces the effectiveness of radiation therapy by limiting the biologically effective dose. An acute increase in tumor oxygenation before radiation treatment should therefore significantly improve the tumor cell kill after radiation. Efforts to increase oxygen delivery to the tumor have not shown positiv...

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

authors： Benej M,Hong X,Vibhute S,Scott S,Wu J,Graves E,Le QT,Koong AC,Giaccia AJ,Yu B,Chen CS,Papandreou I,Denko NC

更新日期：2018-10-16 00:00:00

abstract：:Temporal dynamics of urban warming have been extensively studied at the diurnal scale, but the impact of background climate on the observed seasonality of surface urban heat islands (SUHIs) remains largely unexplored. On seasonal time scales, the intensity of urban-rural surface temperature differences ([Formula: see ...

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

authors： Manoli G,Fatichi S,Bou-Zeid E,Katul GG

更新日期：2020-03-31 00:00:00

abstract：:We have studied the effects of food restriction (FR) and substitution of fish oil (FO; omega 3) for corn oil (CO; omega 6) on breast tumor incidence and survival in mouse mammary tumor virus/v-Ha-ras transgenic (Onco) mice. The diets were as follows: group 1, 5% (wt/wt) CO fed ad libitum (AL); group 2, 5% CO, restrict...

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

authors： Fernandes G,Chandrasekar B,Troyer DA,Venkatraman JT,Good RA

更新日期：1995-07-03 00:00:00

abstract：:The matrix-2 (M2) protein from influenza A virus is a tetrameric, integral transmembrane (TM) protein that plays a vital role in viral replication by proton flux into the virus. The His37 tetrad is a pH sensor in the center of the M2 TM helix that activates the channel in response to the low endosomal pH. M2 consists ...

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

authors： Torabifard H,Panahi A,Brooks CL 3rd

更新日期：2020-02-18 00:00:00

abstract：:Alzheimer's disease (AD) is characterized by a progressive dysfunction of central neurons. Recent experimental evidence indicates that in the cortex, in addition to the silencing of a fraction of neurons, other neurons are hyperactive in amyloid-β (Aβ) plaque-enriched regions. However, it has remained unknown what com...

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

authors： Busche MA,Chen X,Henning HA,Reichwald J,Staufenbiel M,Sakmann B,Konnerth A

更新日期：2012-05-29 00:00:00

abstract：:Glucocorticoids (GCs) are potent anti-inflammatory agents that block cytokine production. We investigated whether GCs also block cytokine signaling via the Janus kinase (Jak)-signal transducer and activator of transcription (STAT) pathway. Dexamethasone inhibited IL-2-induced DNA binding, tyrosine phosphorylation, and...

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

authors： Bianchi M,Meng C,Ivashkiv LB

更新日期：2000-08-15 00:00:00

abstract：:To study the role of low-abundance, embryonic muscle-specific gene transcripts, we have developed a method to screen cDNA clones from embryonic muscle for such sequences. The protocol involves two stages: first, partial enrichment for cDNA clones carrying possible embryo-specific sequences by selecting clones of low-a...

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

authors： Ordahl CP,Kioussis D,Tilghman SM,Ovitt CE,Fornwald J

更新日期：1980-08-01 00:00:00

abstract：:By using titin as a model system, we have demonstrated that fluorescence quenching can be used to study protein folding at the single molecule level. The unfolded titin molecules with multiple dye molecules attached are able to fold to the native state. In the native folded state, the fluorescence from dye molecules i...

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

authors： Zhuang X,Ha T,Kim HD,Centner T,Labeit S,Chu S

更新日期：2000-12-19 00:00:00

abstract：:RNA interference, mediated by small interfering RNAs (siRNAs), is a conserved regulatory process that has evolved as an antiviral defense mechanism in plants and animals. It is not known whether host cells also use siRNAs as an antibacterial defense mechanism in eukaryotes. Here, we report the discovery of an endogeno...

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

authors： Katiyar-Agarwal S,Morgan R,Dahlbeck D,Borsani O,Villegas A Jr,Zhu JK,Staskawicz BJ,Jin H

更新日期：2006-11-21 00:00:00

abstract：:Seven morphologically nontransformed (flat) revertants with reduced tumorigenicity in vivo have been isolated from populations of Kirsten sarcoma virus-transformed NIH 3T3 cells transfected with a cDNA expression library of normal human fibroblasts. Each revertant harbors 1-10 recombinant plasmids per cell and retains...

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

authors： Noda M,Kitayama H,Matsuzaki T,Sugimoto Y,Okayama H,Bassin RH,Ikawa Y

更新日期：1989-01-01 00:00:00

abstract：:Double-positive (DP) thymocytes respond to intrathymic T-cell receptor (TCR) signals by undergoing positive selection and lineage differentiation into single-positive (SP) mature cells. Concomitant with these well-characterized events is the acquisition of a mature T-cell gene expression program characterized by the i...

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

authors： Shi LZ,Saravia J,Zeng H,Kalupahana NS,Guy CS,Neale G,Chi H

更新日期：2017-01-03 00:00:00

abstract：:Dual inactivation of PTEN and INK4a/ARF tumor suppressor genes is a common feature observed in a broad spectrum of human cancer types. To validate functional collaboration between these genes in tumor suppression, we examined the biological consequences of Pten and/or Ink4a/Arf deficiency in cells and mice. Relative t...

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

authors： You MJ,Castrillon DH,Bastian BC,O'Hagan RC,Bosenberg MW,Parsons R,Chin L,DePinho RA

更新日期：2002-02-05 00:00:00

abstract：:Three-dimensional microfluidic systems were fabricated and used to pattern proteins and mammalian cells on a planar substrate. The three-dimensional topology of the microfluidic network in the stamp makes this technique a versatile one with which to pattern multiple types of proteins and cells in complex, discontinuou...

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

authors： Chiu DT,Jeon NL,Huang S,Kane RS,Wargo CJ,Choi IS,Ingber DE,Whitesides GM

更新日期：2000-03-14 00:00:00

abstract：:Rickettsiae are responsible for some of the most devastating human infections. A high infectivity and severe illness after inhalation make some rickettsiae bioterrorism threats. We report that deletion of the exchange protein directly activated by cAMP (Epac) gene, Epac1, in mice protects them from an ordinarily letha...

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

authors： Gong B,Shelite T,Mei FC,Ha T,Hu Y,Xu G,Chang Q,Wakamiya M,Ksiazek TG,Boor PJ,Bouyer DH,Popov VL,Chen J,Walker DH,Cheng X

更新日期：2013-11-26 00:00:00

abstract：:Classic physiology studies dating to the 1930s demonstrate that moderate or transient glucocorticoid (GC) exposure improves muscle performance. The ergogenic properties of GCs are further evidenced by their surreptitious use as doping agents by endurance athletes and poorly understood efficacy in Duchenne muscular dys...

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

authors： Morrison-Nozik A,Anand P,Zhu H,Duan Q,Sabeh M,Prosdocimo DA,Lemieux ME,Nordsborg N,Russell AP,MacRae CA,Gerber AN,Jain MK,Haldar SM

更新日期：2015-12-08 00:00:00

abstract：:Breast cancers show variable sensitivity to paclitaxel. There is no diagnostic test to identify tumors that are sensitive to this drug. We used U133A chips to identify genes that are associated with pathologic complete response (pCR) to preoperative paclitaxel-containing chemotherapy in stage I-III breast cancer (n = ...

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

authors： Rouzier R,Rajan R,Wagner P,Hess KR,Gold DL,Stec J,Ayers M,Ross JS,Zhang P,Buchholz TA,Kuerer H,Green M,Arun B,Hortobagyi GN,Symmans WF,Pusztai L

更新日期：2005-06-07 00:00:00

abstract：:Endocrine therapy resistance invariably develops in advanced estrogen receptor-positive (ER+) breast cancer, but the underlying mechanisms are largely unknown. We have identified C-terminal SRC kinase (CSK) as a critical node in a previously unappreciated negative feedback loop that limits the efficacy of current ER-t...

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

authors： Xiao T,Li W,Wang X,Xu H,Yang J,Wu Q,Huang Y,Geradts J,Jiang P,Fei T,Chi D,Zang C,Liao Q,Rennhack J,Andrechek E,Li N,Detre S,Dowsett M,Jeselsohn RM,Liu XS,Brown M

更新日期：2018-07-31 00:00:00

abstract：:Betidamino acids (a contraction of "beta" position and "amide") are N'-monoacylated (optionally, N'-monoacylated and N-mono- or N,N'-dialkylated) aminoglycine derivatives in which each N'acyl/alkyl group may mimic naturally occurring amino acid side chains or introduce novel functionalities. Betidamino acids are most ...

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

authors： Rivier JE,Jiang G,Koerber SC,Porter J,Simon L,Craig AG,Hoeger CA

更新日期：1996-03-05 00:00:00

abstract：:When Drosophila melanogaster embryos were ligated at very early stages of nuclear multiplication (45-60 min after egg deposition) for the entire period of embryogenesis, egg fragments of variable sizes were able to continue development up to the hatching stage. These ligated embryos differentiated larval structures; a...

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

authors： Schubiger G,Moseley RC,Wood WJ

更新日期：1977-05-01 00:00:00

abstract：:Cyclic GMP (cGMP) is an important second messenger in eukaryotes. It is formed by guanylyl cyclases (GCs), members of the nucleotidyl cyclases class III, which also comprises adenylyl cyclases (ACs) from most organisms. To date, no structures of eukaryotic GCs are available, and all bacterial class III proteins were f...

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

authors： Rauch A,Leipelt M,Russwurm M,Steegborn C

更新日期：2008-10-14 00:00:00

abstract：:The high excitation energy-transfer efficiency demanded in photosynthetic organisms relies on the optimal pigment-protein binding orientation in the individual protein complexes and also on the overall architecture of the photosystem. In green sulfur bacteria, the membrane-attached Fenna-Matthews-Olson (FMO) antenna p...

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

authors： Wen J,Zhang H,Gross ML,Blankenship RE

更新日期：2009-04-14 00:00:00