Crystal structure of an RNA.DNA hybrid reveals intermolecular intercalation: dimer formation by base-pair swapping.

abstract：:Polyadenylation, the process of eukaryotic mRNA 3' end formation, is essential for gene expression and cell viability. Polyadenylation of male germ cell mRNAs is unusual, exhibiting increased alternative polyadenylation, decreased AAUAAA polyadenylation signal use, and reduced downstream sequence element dependence. C...

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

authors： Dass B,Tardif S,Park JY,Tian B,Weitlauf HM,Hess RA,Carnes K,Griswold MD,Small CL,Macdonald CC

更新日期：2007-12-18 00:00:00

abstract：:Encoding activity in the medial temporal lobe, presumably evoked by the presentation of stimuli (postonset activity), is known to predict subsequent memory. However, several independent lines of research suggest that preonset activity also affects subsequent memory. We investigated the role of preonset and postonset s...

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

authors： Urgolites ZJ,Wixted JT,Goldinger SD,Papesh MH,Treiman DM,Squire LR,Steinmetz PN

更新日期：2020-06-16 00:00:00

abstract：:The leading terms in the energy of a general substituted ethane are derived in explicit form as a function of the torsional angle theta, the substituent electronegativities, and their mutual overlaps. The energy is found to be the sum of all four overlaps between pairs of asymmetry orbitals, and satisfies the requisit...

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

authors： Salem L,Hoffmann R,Otto P

更新日期：1973-02-01 00:00:00

abstract：:Various enzymatic derivatives of the murine myeloma protein IgA(MOPC-315) were subjected to hapten-binding quantitation and circular dichroic analysis in an attempt to ascertain the structural localization and functional definition of the immunoglobulin active site. The extrinsic Cotton effects observed with near satu...

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

authors： Merz DC,Litman GW,Good RA

更新日期：1974-05-01 00:00:00

abstract：:T cells that have been immunized to express optimal levels of contact hypersensitivity upon adoptive transfer to normal animals can be inhibited from doing so by incubating them with an antigen-specific T suppressor factor. This factor is composed of at least two subunits which come from cells expressing different Ly ...

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

authors： Ptak W,Rosenstein RW,Gershon RK

更新日期：1982-04-01 00:00:00

abstract：:Although rigorous measures of similarity for sequence and structure are now well established, the problem of defining functional relationships has been particularly daunting. Here, we present several manifold embedding techniques to compute distances between Gene Ontology (GO) functional annotations and consequently e...

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

authors： Lerman G,Shakhnovich BE

更新日期：2007-07-03 00:00:00

abstract：:Antibodies capable of decarboxylating orotate were sought by immunization with a hapten designed to elicit antibodies with combining sites that resemble the orotate-binding and catalytic portion of the active site of the enzyme orotidine 5'-monophosphate (OMP) decarboxylase (orotidine-5'-monophosphate carboxy-lyase, E...

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

authors： Smiley JA,Benkovic SJ

更新日期：1994-08-30 00:00:00

abstract：:A key element for the development of suitable anti-cancer drugs is the identification of cancer-specific enzymatic activities that can be therapeutically targeted. Mucosa-associated lymphoid tissue transformation protein 1 (MALT1) is a proto-oncogene that contributes to tumorigenesis in diffuse large B-cell lymphoma (...

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

authors： Hailfinger S,Lenz G,Ngo V,Posvitz-Fejfar A,Rebeaud F,Guzzardi M,Penas EM,Dierlamm J,Chan WC,Staudt LM,Thome M

更新日期：2009-11-24 00:00:00

abstract：:An increasing amount of investment has been devoted to protecting and restoring ecosystem services worldwide. The efficiency of conservation investments, including payments for ecosystem services (PES), has been found to be affected by biological, political, economic, demographic, and social factors, but little is kno...

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

authors： Chen X,Lupi F,He G,Liu J

更新日期：2009-07-14 00:00:00

abstract：:The study of the metabolome presents numerous challenges, first among them being the cataloging of its constituents. A step in this direction will be the development of tools to identify metabolites that share common structural features. The importance of sulfated molecules in cell-cell communication motivated us to d...

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

authors： Mougous JD,Leavell MD,Senaratne RH,Leigh CD,Williams SJ,Riley LW,Leary JA,Bertozzi CR

更新日期：2002-12-24 00:00:00

abstract：:A Chinese hamster ovary cell (CHO) mutant (strain 58), defective in CDP-choline synthetase (cholinephosphate cytidylyltransferase; CTP:cholinephosphate cytidylyltransferase, EC 2.7.7.15), is temperature sensitive for growth and contains less than half of the normal amount of phosphatidylcholine under nonpermissive con...

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

authors： Esko JD,Nishijima M,Raetz CR

更新日期：1982-03-01 00:00:00

abstract：:From within an albino melanocyte line grown in vitro we identified and cloned cells that apparently had reverted to wild type. We sequenced a part of the tyrosinase gene, encompassing a candidate mutation, from wild-type, albino, and revertant cell DNAs. The revertant cells contain, on one chromosome, a perfect base r...

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

authors： Jackson IJ,Bennett DC

更新日期：1990-09-01 00:00:00

abstract：:Although antibodies to HLA play a role in the pathogenesis of diseases processes such as rejection of transplanted organs, the precise mechanisms by which antibodies cause tissue injury are not completely understood. We hypothesized that antibodies to host tissues cause inflammation in part by activating endothelial e...

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

authors： Yamakuchi M,Kirkiles-Smith NC,Ferlito M,Cameron SJ,Bao C,Fox-Talbot K,Wasowska BA,Baldwin WM 3rd,Pober JS,Lowenstein CJ

更新日期：2007-01-23 00:00:00

abstract：:Fluctuations in resting-state functional connectivity occur but their behavioral significance remains unclear, largely because correlating behavioral state with dynamic functional connectivity states (DCS) engages probes that disrupt the very behavioral state we seek to observe. Observing spontaneous eyelid closures f...

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

authors： Wang C,Ong JL,Patanaik A,Zhou J,Chee MW

更新日期：2016-08-23 00:00:00

abstract：:Aberrant transcription of the pericentromeric human satellite II (HSATII) repeat is present in a wide variety of epithelial cancers. In deriving experimental systems to study its deregulation, we observed that HSATII expression is induced in colon cancer cells cultured as xenografts or under nonadherent conditions in ...

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

authors： Bersani F,Lee E,Kharchenko PV,Xu AW,Liu M,Xega K,MacKenzie OC,Brannigan BW,Wittner BS,Jung H,Ramaswamy S,Park PJ,Maheswaran S,Ting DT,Haber DA

更新日期：2015-12-08 00:00:00

abstract：:In everyday life, a macroscopic valve is a device with a movable control element that regulates the flow of gases or liquids by blocking and opening passageways. Construction of such a device on the nanoscale level requires (i) suitably proportioned movable control elements, (ii) a method for operating them on demand,...

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

authors： Nguyen TD,Tseng HR,Celestre PC,Flood AH,Liu Y,Stoddart JF,Zink JI

更新日期：2005-07-19 00:00:00

abstract：:We have evaluated two synthetic epothilone analogues lacking the 12,13-epoxide functionality, 12,13-desoxyepothilone B (dEpoB), and 12,13-desoxyepothilone F (dEpoF). The concentrations required for 50% growth inhibition (IC(50)) for a variety of anticancer agents were measured in CCRF-CEM/VBL1000 cells (2,048-fold res...

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

authors： Chou TC,O'Connor OA,Tong WP,Guan Y,Zhang ZG,Stachel SJ,Lee C,Danishefsky SJ

更新日期：2001-07-03 00:00:00

abstract：:The conservation of developmental functions exerted by Antp-class homeoproteins in protostomes and deuterostomes suggested that homologs with related functions are present in diploblastic animals. Our phylogenetic analyses showed that Antp-class homeodomains belong either to non-Hox or to Hox/paraHox families. Among t...

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

authors： Gauchat D,Mazet F,Berney C,Schummer M,Kreger S,Pawlowski J,Galliot B

更新日期：2000-04-25 00:00:00

abstract：:microRNAs comprise a few percent of animal genes and have been recognized as important regulators of a diverse range of biological processes. Understanding the biological functions of miRNAs requires effective means to identify their targets. Combined efforts from computational prediction, miRNA over-expression or dep...

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

authors： Hong X,Hammell M,Ambros V,Cohen SM

更新日期：2009-09-01 00:00:00

abstract：:The DNA of functional cis-regulatory modules displays extensive sequence conservation in comparisons of genomes from modestly distant species. Patches of sequence that are several hundred base pairs in length within these modules are often seen to be 80-95% identical, although the flanking sequence cannot even be alig...

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

authors： Cameron RA,Chow SH,Berney K,Chiu TY,Yuan QA,Krämer A,Helguero A,Ransick A,Yun M,Davidson EH

更新日期：2005-08-16 00:00:00

abstract：:This paper describes a variety of statistical methods for obtaining precise quantitative estimates of the similarities and differences in the structures of semantic domains in different languages. The methods include comparing mean correlations within and between groups, principal components analysis of interspeaker c...

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

authors： Romney AK,Moore CC,Batchelder WH,Hsia TL

更新日期：2000-01-04 00:00:00

abstract：:ERK6, a mitogen-activated protein (MAP) kinase-related serine/threonine kinase, is highly expressed in human skeletal muscle and appears to function as a signal transducer during differentiation of myoblasts to myotubes. In transfected 293 cells, activation of the 45-kDa enzyme results in tyrosine-phosphorylated 46- a...

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

authors： Lechner C,Zahalka MA,Giot JF,Møller NP,Ullrich A

更新日期：1996-04-30 00:00:00

abstract：:In the United States, the iconic groundfish fishery for Gulf of Maine cod has endured several dramatic reductions in annual catch limits and been federally declared an economic disaster. Using a repeated cross-sectional survey of fishing captains to assess potential social impacts of the fishery failure, we found that...

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

authors： Scyphers SB,Picou JS,Grabowski JH

更新日期：2019-11-12 00:00:00

abstract：:Fibronectin mediates the adhesion of cells to collagen by first binding to the collagen substrate, followed by attachment of the cells to the fibronectin-collagen complex. Bovine brain gangliosides were found to block fibronectin-mediated cell adhesion to collagen in a concentration-dependent manner. The gangliosides ...

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

authors： Kleinman HK,Martin GR,Fishman PH

更新日期：1979-07-01 00:00:00

abstract：:The discovery of high-temperature superconductivity in iron pnictides raised the possibility of an unconventional superconducting mechanism in multiband materials. The observation of Fermi-surface (FS)-dependent nodeless superconducting gaps suggested that inter-FS interactions may play a crucial role in superconducti...

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

authors： Terashima K,Sekiba Y,Bowen JH,Nakayama K,Kawahara T,Sato T,Richard P,Xu YM,Li LJ,Cao GH,Xu ZA,Ding H,Takahashi T

更新日期：2009-05-05 00:00:00

abstract：:Cytoplasmic dynein is a microtubule-based motor protein complex that plays important roles in a wide range of fundamental cellular processes, including vesicular transport, mitosis, and cell migration. A single major form of cytoplasmic dynein associates with membranous organelles, mitotic kinetochores, the mitotic an...

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

authors： Williams JC,Roulhac PL,Roy AG,Vallee RB,Fitzgerald MC,Hendrickson WA

更新日期：2007-06-12 00:00:00

abstract：:This study quantifies sex differences in the diurnal and circadian variation of sleep and waking while controlling for menstrual cycle phase and hormonal contraceptive use. We compared the diurnal and circadian variation of sleep and alertness of 8 women studied during two phases of the menstrual cycle and 3 women stu...

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

authors： Boivin DB,Shechter A,Boudreau P,Begum EA,Ng Ying-Kin NM

更新日期：2016-09-27 00:00:00

abstract：:The 20S proteasome core particle (20S CP) plays an integral role in cellular homeostasis by degrading proteins no longer required for function. The process is, in part, controlled via gating residues localized to the ends of the heptameric barrel-like CP structure that occlude substrate entry pores, preventing unregul...

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

authors： Huang R,Pérez F,Kay LE

更新日期：2017-11-14 00:00:00

abstract：:Purified NADPH:cytochrome c (P-450) reductase (FpT; NADPH-ferrihemoprotein oxidoreductase, EC 1.6.2.4) can reductively activate mitomycin antibiotics through a one-electron reduction to species that alkylate DNA. To assess the involvement of FpT in the intracellular activation of the mitomycins, transfectants overexpr...

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

authors： Belcourt MF,Hodnick WF,Rockwell S,Sartorelli AC

更新日期：1996-01-09 00:00:00

abstract：:Saposin A, a heat-stable 16-kDa glycoprotein, was isolated from Gaucher disease spleen and purified to homogeneity. Chemical sequencing from its amino terminus and of peptides obtained by digestion with protease from Staphylococcus aureus strain V-8 demonstrated that saposin A is derived from proteolytic processing of...

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

authors： Morimoto S,Martin BM,Yamamoto Y,Kretz KA,O'Brien JS,Kishimoto Y

更新日期：1989-05-01 00:00:00