Elastic free energy of anisotropic helical ribbons as metastable intermediates in the crystallization of cholesterol.

abstract：:Phosphatidylinositol 3 (PI3)-kinase enhancer (PIKE) is a nuclear GTPase that enhances PI3-kinase activity in a GTP-dependent manner. Both PIKE-L and -A isoforms contain GTPase, pleckstrin homology (PH), ADP ribosylation factor-GTPase-activating protein, and two ankyrin repeats domains, and C-terminal ADP ribosylation ...

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

authors： Hu Y,Liu Z,Ye K

更新日期：2005-11-15 00:00:00

abstract：:We measured the superconducting transition temperature of (6)Li between 16 and 26 GPa, and report the lightest system to exhibit superconductivity to date. The superconducting phase diagram of (6)Li is compared with that of (7)Li through simultaneous measurement in a diamond anvil cell (DAC). Below 21 GPa, Li exhibits...

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

authors： Schaeffer AM,Temple SR,Bishop JK,Deemyad S

更新日期：2015-01-06 00:00:00

abstract：:We report direct evidence for the existence of an iron(IV)-hydroxide. Resonance Raman measurements on chloroperoxidase compound II (CPO-II) reveal an isotope ((18)O and (2)H)-sensitive band at nu(Fe-O) = 565 cm(-1). Preparation of CPO-II in H(2)O using H(2)(18)O(2) results in a red-shift of 22 cm(-1), while preparatio...

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

authors： Stone KL,Behan RK,Green MT

更新日期：2006-08-15 00:00:00

abstract：:The O(2) reduction site of cytochrome c oxidase (CcO), comprising iron (Fe(a3)) and copper (Cu(B)) ions, is probed by x-ray structural analyses of CO, NO, and CN(-) derivatives to investigate the mechanism of the complete reduction of O(2). Formation of the derivative contributes to the trigonal planar coordination of...

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

authors： Muramoto K,Ohta K,Shinzawa-Itoh K,Kanda K,Taniguchi M,Nabekura H,Yamashita E,Tsukihara T,Yoshikawa S

更新日期：2010-04-27 00:00:00

abstract：:Pyrroline-carboxy-lysine (Pcl) is a demethylated form of pyrrolysine that is generated by the pyrrolysine biosynthetic enzymes when the growth media is supplemented with D-ornithine. Pcl is readily incorporated by the unmodified pyrrolysyl-tRNA/tRNA synthetase pair into proteins expressed in Escherichia coli and in ma...

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

authors： Ou W,Uno T,Chiu HP,Grünewald J,Cellitti SE,Crossgrove T,Hao X,Fan Q,Quinn LL,Patterson P,Okach L,Jones DH,Lesley SA,Brock A,Geierstanger BH

更新日期：2011-06-28 00:00:00

abstract：:Within the mammalian testis, specialized tight junctions between somatic Sertoli cells create basal and apical polarity within the cells, restrict movement of molecules between cells, and separate the seminiferous epithelium into basal and adluminal compartments. These tight junctions form the basis of the blood-testi...

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

authors： Meng J,Holdcraft RW,Shima JE,Griswold MD,Braun RE

更新日期：2005-11-15 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

abstract：:Topological mechanical metamaterials are artificial structures whose unusual properties are protected very much like their electronic and optical counterparts. Here, we present an experimental and theoretical study of an active metamaterial--composed of coupled gyroscopes on a lattice--that breaks time-reversal symmet...

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

authors： Nash LM,Kleckner D,Read A,Vitelli V,Turner AM,Irvine WT

更新日期：2015-11-24 00:00:00

abstract：:Multiple steps of plant growth and development rely on rapid cell elongation during which secretory and endocytic trafficking via the trans-Golgi network (TGN) plays a central role. Here, we identify the ECHIDNA (ECH) protein from Arabidopsis thaliana as a TGN-localized component crucial for TGN function. ECH partiall...

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

authors： Gendre D,Oh J,Boutté Y,Best JG,Samuels L,Nilsson R,Uemura T,Marchant A,Bennett MJ,Grebe M,Bhalerao RP

更新日期：2011-05-10 00:00:00

abstract：:The mechanism by which mammalian cells acquire resistance to chemotherapeutic agents has been investigated by using molecular genetic techniques. LZ and C5, two independently derived multidrug-resistant Chinese hamster cell lines, share specific amplified DNA sequences. We demonstrate that commonly amplified DNA seque...

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

authors： Gros P,Croop J,Roninson I,Varshavsky A,Housman DE

更新日期：1986-01-01 00:00:00

abstract：:The photosynthetic apparatus converts light into chemical energy by a series of reactions that give rise to a coupled flow of electrons and protons that generate reducing power and ATP, respectively. A key intermediate in these reactions is plastoquinone (PQ), the most abundant electron and proton (hydrogen) carrier i...

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

authors： McCauley SW,Melis A,Tang GM,Arnon DI

更新日期：1987-12-01 00:00:00

abstract：:A two-dimensional model of the expansion of a crack in an elastic medium is considered in which friction depends on the slip rate and the modulus of cohesion depends on the speed of expansion of the crack. Elastic waves are neglected (quasi-static model). Under some conditions, the expansion of the crack is realized b...

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

authors： Barenblatt GI,Keilis-Borok VI,Vishik MM

更新日期：1981-09-01 00:00:00

abstract：:The respiratory burst oxidase of neutrophils can be activated in a cell-free system in which plasma membranes, cytosol, Mg2+, and a membrane-perturbing detergent, such as arachidonate or sodium dodecyl sulfate, are all required. Using the technique of preparative isoelectric focusing, the cytosol factor required for o...

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

authors： Curnutte JT,Scott PJ,Mayo LA

更新日期：1989-02-01 00:00:00

abstract：:Isolation and chromatography of collagen from chick cartilage revealed an excess of alpha1 relative to alpha2-chains. Characterization of the cyanogen bromide peptides from the alpha1 fraction indicated the presence of two homologous forms of alpha1. The results suggest that cartilage contains two collagens, one ident...

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

authors： Miller EJ,Matukas VJ

更新日期：1969-12-01 00:00:00

abstract：:We have studied the genetic interactions between mutant alleles in 12 genes, designated PER1-PER12, which are essential for peroxisome biogenesis in the yeast Hansenula polymorpha. Recessive mutations in any of these genes determined three different morphological phenotypes: (i) complete absence of peroxisomes (Per-);...

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

authors： Titorenko VI,Waterham HR,Cregg JM,Harder W,Veenhuis M

更新日期：1993-08-15 00:00:00

abstract：:Three fluorescein-labeled lectins have been shown to exhibit specificity for the surface of cells in different layers of the epidermis in the newborn rat. An isolectin from seeds of Bandeiraea simplicifolia with specificity for alpha-D-galactosyl end groups labeled the basal and lower spinous cells; a lectin from Ulex...

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

authors： Brabec RK,Peters BP,Bernstein IA,Gray RH,Goldstein IJ

更新日期：1980-01-01 00:00:00

abstract：:Gene therapy of the brain is hindered by the presence of the blood-brain barrier (BBB), which prevents the brain uptake of bloodborne gene formulations. Exogenous genes have been expressed in the brain after invasive routes of administration, such as craniotomy or intracarotid arterial infusion of noxious agents causi...

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

authors： Shi N,Pardridge WM

更新日期：2000-06-20 00:00:00

abstract：:Mycobacterium abscessus (Mabs) is a rapidly growing Mycobacterium and an emerging pathogen in humans. Transitioning from a smooth (S) high-glycopeptidolipid (GPL) producer to a rough (R) low-GPL producer is associated with increased virulence in zebrafish, which involves the formation of massive serpentine cords, absc...

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

authors： Halloum I,Carrère-Kremer S,Blaise M,Viljoen A,Bernut A,Le Moigne V,Vilchèze C,Guérardel Y,Lutfalla G,Herrmann JL,Jacobs WR Jr,Kremer L

更新日期：2016-07-19 00:00:00

abstract：:Phylogenetic differences in acetylcholine receptors from skeletal neuromuscular synapses of various species of snakes and lizards have been investigated, using the snake venom alpha-neurotoxins alpha-atratoxin (cobrotoxin) and alpha-bungarotoxin. The acetylcholine receptors of the phylogenetically primitive lizards, l...

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

authors： Burden SJ,Hartzell HC,Yoshikami D

更新日期：1975-08-01 00:00:00

abstract：:Agonist binding to the muscarinic receptor in rat cerebral cortex membranes was studied by using the neurotransmitter itself, [3H]acetylcholine [( 3H]AcCho). By using 10 microM atropine or oxotremorine to define specific binding, it was possible to demonstrate specific binding of [3H]AcCho that was sensitive to muscar...

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

authors： Gurwitz D,Kloog Y,Sokolovsky M

更新日期：1984-06-01 00:00:00

abstract：:Ring-shaped hexameric helicases and translocases support essential DNA-, RNA-, and protein-dependent transactions in all cells and many viruses. How such systems coordinate ATPase activity between multiple subunits to power conformational changes that drive the engagement and movement of client substrates is a fundame...

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

authors： Thomsen ND,Lawson MR,Witkowsky LB,Qu S,Berger JM

更新日期：2016-11-29 00:00:00

abstract：:The GTP/GDP nucleotide switch in Ras superfamily GTPases generally involves differential affinity toward downstream effectors, with the GTP-bound state having a higher affinity for effector than the GDP-bound state. We have developed a quantitative model of allosteric regulation of the Wiskott-Aldrich syndrome protein...

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

authors： Leung DW,Rosen MK

更新日期：2005-04-19 00:00:00

abstract：:Malaria control is threatened by a limited pipeline of effective pharmaceuticals against drug-resistant strains of Plasmodium falciparum Components of the mitochondrial electron transport chain (ETC) are attractive targets for drug development, owing to exploitable differences between the parasite and human ETC. Disru...

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

authors： Lane KD,Mu J,Lu J,Windle ST,Liu A,Sun PD,Wellems TE

更新日期：2018-06-12 00:00:00

abstract：:Treatment of the Daudi Burkitt lymphoma-derived cell line with human interferon alpha, which inhibits cell proliferation in this system, induces differentiation of these B-lymphoid cells into cells with a plasmacytoid phenotype. This differentiation, quantified by the appearance of surface antigens characteristic of m...

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

authors： Exley R,Gordon J,Clemens MJ

更新日期：1987-09-01 00:00:00

abstract：:The rationale for genome-wide association study (GWAS) results is sequence variation in cis-regulatory elements (CREs) modulating a target gene's expression as the major cause of trait variation. To understand the complete molecular landscape of one of these GWAS loci, we performed in vitro reporter screens in cardiom...

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

authors： Kapoor A,Lee D,Zhu L,Soliman EZ,Grove ML,Boerwinkle E,Arking DE,Chakravarti A

更新日期：2019-05-28 00:00:00

abstract：:Nonribosomal peptide synthetases (NRPSs) and polyketide synthases are large, multidomain enzymes that biosynthesize a number of pharmaceutically important natural products. The recognition of biosynthetic intermediates, displayed via covalent attachment to carrier proteins, by catalytic domains is critical for NRPS an...

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

authors： Lai JR,Fischbach MA,Liu DR,Walsh CT

更新日期：2006-04-04 00:00:00

abstract：:In an investigation to determine how proteins are localized within the nucleus of a cell, we demonstrate that the restriction endonuclease EcoRI is able to enter and function within the nucleus of Saccharomyces cerevisiae when this prokaryotic protein is synthesized in vivo. The EcoRI endonuclease was produced in yeas...

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

authors： Barnes G,Rine J

更新日期：1985-03-01 00:00:00

abstract：:The rearrangement of immunoglobulin genes in B-lymphocyte precursors requires the expression of the recombination activating genes (Rag), which leads to the generation of a highly diverse B-cell repertoire. We can use the level of Rag-1 mRNA in the bone marrow as an index of its capacity to support the maturation of B...

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

authors： Ben-Yehuda A,Szabo P,Dyall R,Weksler ME

更新日期：1994-12-06 00:00:00

abstract：:We developed two solid-phase reagent systems for microscopic visualization and characterization of melanocyte-stimulating hormone (MSH) receptors of melanoma cells. Multiple copies of [Nle-4,D-Phe-7]-alpha-MSH, a potent analog of alpha-MSH, were conjugated to microspheres (latex beads) or macrospheres (polyamide beads...

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

authors： Sharma SD,Jiang J,Hadley ME,Bentley DL,Hruby VJ

更新日期：1996-11-26 00:00:00

abstract：:A cofactor needed for the reduction of CDP-4-keto-6-deoxy-D-glucose to CDP-4-keto-3,6-dideoxy D-glucose has been detected and purified. Its spectra in neutral, acid, and basic solutions, its behavior on thin-layer chromatography, and other properties led to its identification as pyridoxamine-5'-phosphate. Moreover, au...

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

authors： Gonzalez-Porque P,Strominger JL

更新日期：1972-06-01 00:00:00