Niche conservatism above the species level.

abstract：:In colloidal systems, the interplay between the short range attraction and long-range repulsion can lead to a low density associated state consisting of clusters of individual particles. Recently, such an equilibrium cluster phase was also reported for concentrated solutions of lysozyme at low ionic strength and close...

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

authors： Shukla A,Mylonas E,Di Cola E,Finet S,Timmins P,Narayanan T,Svergun DI

更新日期：2008-04-01 00:00:00

abstract：:Niemann-Pick C1 (NPC1) and NPC2 proteins are indispensable for the export of LDL-derived cholesterol from late endosomes. Mutations in these proteins result in Niemann-Pick type C disease, a lysosomal storage disease. Despite recent reports of the NPC1 structure depicting its overall architecture, the function of its ...

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

authors： Li X,Lu F,Trinh MN,Schmiege P,Seemann J,Wang J,Blobel G

更新日期：2017-08-22 00:00:00

abstract：:An enzyme that reduces methionine sulfoxide [Met(O)] residues in proteins [peptide Met(O) reductase (MsrA), EC 1.8.4.6; originally identified in Escherichia coli] was purified from bovine liver, and the cDNA encoding this enzyme was cloned and sequenced. The mammalian homologue of E. coli msrA (also called pmsR) cDNA ...

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

authors： Moskovitz J,Weissbach H,Brot N

更新日期：1996-03-05 00:00:00

abstract：:Tumor necrosis factor alpha (TNF-alpha), also known as cachectin, was demonstrated to induce the expression of human immunodeficiency virus (HIV) in a chronically infected T-cell clone (ACH-2). Concentrations of recombinant TNF-alpha as low as 50 pg/ml induced a significant increase over background of HIV expression i...

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

authors： Folks TM,Clouse KA,Justement J,Rabson A,Duh E,Kehrl JH,Fauci AS

更新日期：1989-04-01 00:00:00

abstract：:Mouse lymphocytic cells of the established line GF-14 were allowed to accumulate intracellular 3H-labeled aminoisobutyric acid (AIB), frozen, and stored over liquid N2. After internal radiation had reduced survival to 1 in 10(4), survivors were plated and tested for their ability to transport AIB. Out of 200 clones te...

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

authors： Finkelstein MC,Slayman CW,Adelberg EA

更新日期：1977-10-01 00:00:00

abstract：:Translesion synthesis at replication-blocking lesions requires the induction of proteins that are controlled by the SOS system in Escherichia coli. Of the proteins identified so far, UmuD', UmuC, and RecA* were shown to facilitate replication across UV-light-induced lesions, yielding both error-free and mutagenic tran...

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

authors： Fuchs RP,Napolitano RL

更新日期：1998-10-27 00:00:00

abstract：:We propose a phylogeny for the evolution of tRNA that is based on the ubiquity and conservation of tRNA-like structures in the replication of contemporary genomes. This phylogeny is unique in suggesting that the function of tRNA in replication dates back to the very beginnings of life on earth, before the advent of te...

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

authors： Maizels N,Weiner AM

更新日期：1994-07-19 00:00:00

abstract：:Growth hormone (GH) has previously been implicated in T-cell development, and here we test its efficacy in promoting T-lymphocyte engraftment in mice with severe combined immune deficiency (SCID). SCID mice receiving syngeneic thymocytes and treated with recombinant human GH (rhGH) had significantly better T-cell engr...

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

authors： Murphy WJ,Durum SK,Longo DL

更新日期：1992-05-15 00:00:00

abstract：:To test whether a 30S ribosomal subunitformylmethionyl-tRNA-mRNA complex is an obligatory intermediate in protein synthesis, 70S ribosomes from Escherichia coli were crosslinked with the bifunctional imidoester, dimethylsuberimidate. Crosslinked ribosomes contained covelently joined 30S and 50S subunits, as judged by ...

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

authors： Slobin LI

更新日期：1972-12-01 00:00:00

abstract：:"Functional connectivity" techniques are commonplace tools for studying brain organization. A critical element of these analyses is to distinguish variance due to neurobiological signals from variance due to nonneurobiological signals. Multiecho fMRI techniques are a promising means for making such distinctions based ...

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

authors： Power JD,Plitt M,Gotts SJ,Kundu P,Voon V,Bandettini PA,Martin A

更新日期：2018-02-27 00:00:00

abstract：:Questions that still surround the origin and early dispersals of maize (Zea mays L.) result in large part from the absence of information on its early history from the Balsas River Valley of tropical southwestern Mexico, where its wild ancestor is native. We report starch grain and phytolith data from the Xihuatoxtla ...

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

authors： Piperno DR,Ranere AJ,Holst I,Iriarte J,Dickau R

更新日期：2009-03-31 00:00:00

abstract：:There is considerable interest in engineering plant cell wall components, particularly lignin, to improve forage quality and biomass properties for processing to fuels and bioproducts. However, modifying lignin content and/or composition in transgenic plants through down-regulation of lignin biosynthetic enzymes can i...

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

authors： Gallego-Giraldo L,Liu C,Pose-Albacete S,Pattathil S,Peralta AG,Young J,Westpheling J,Hahn MG,Rao X,Knox JP,De Meester B,Boerjan W,Dixon RA

更新日期：2020-02-11 00:00:00

abstract：:DNA polymerases from Xenopus laevis oocytes, unfertilized eggs, and kidney cells grown in culture have been characterized. The same three major DNA polymerase activities are present in all cell types examined. We attempt to relate the characteristics of amphibian enzymes to those of mammalian polymerases. ...

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

authors： Tatò F,Gandini DA,Tocchini-Valentini GP

更新日期：1974-09-01 00:00:00

abstract：:Excited electronic states created by UV excitation of the diribonucleoside monophosphates ApA, ApG, ApC, ApU, and CpG were studied by the femtosecond transient-absorption technique. Bleach recovery signals recorded at 252 nm show that long-lived excited states are formed in all five dinucleosides. The lifetimes of the...

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

authors： Takaya T,Su C,de La Harpe K,Crespo-Hernández CE,Kohler B

更新日期：2008-07-29 00:00:00

abstract：:Previous studies have shown that the helical RecA nucleoprotein filament formed on a circular single strand of DNA causes the progressive, directional transfer of a complementary strand from naked linear duplex DNA to the nucleoprotein filament, even when the duplex contains a sizable heterologous insertion. Since Rec...

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

authors： Jwang B,Radding CM

更新日期：1992-08-15 00:00:00

abstract：:High-entropy alloys are made from random mixtures of principal elements on simple lattices, stabilized by a high mixing entropy. The recently discovered body-centered cubic (BCC) Ta-Nb-Hf-Zr-Ti high-entropy alloy superconductor appears to display properties of both simple crystalline intermetallics and amorphous mater...

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

authors： von Rohr F,Winiarski MJ,Tao J,Klimczuk T,Cava RJ

更新日期：2016-11-15 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：:Activator-dependent recruitment of TFIID initiates formation of the transcriptional preinitiation complex. TFIID binds core promoter DNA elements and directs the assembly of other general transcription factors, leading to binding of RNA polymerase II and activation of RNA synthesis. How TATA box-binding protein (TBP) ...

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

authors： Wright KJ,Marr MT 2nd,Tjian R

更新日期：2006-08-15 00:00:00

abstract：:Male infertility, affecting as many as 10% of the adult population, is an extremely prevalent disorder. In most cases, the cause of the condition is unknown, and genetic factors that might affect male fertility, other than some sequences on the Y chromosome, have not been identified. We report here that male mice hete...

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

authors： Huang LS,Voyiaziakis E,Chen HL,Rubin EM,Gordon JW

更新日期：1996-10-01 00:00:00

abstract：:Carbonic anhydrases (CAs; EC 4.2.1.1) are metalloenzymes present in mammals with 16 isoforms that differ in terms of catalytic activity as well as cellular and tissue distribution. CAs catalyze the conversion of CO2 to bicarbonate and protons and are involved in various physiological processes, including learning and ...

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

authors： Schmidt SD,Costa A,Rani B,Godfried Nachtigall E,Passani MB,Carta F,Nocentini A,de Carvalho Myskiw J,Furini CRG,Supuran CT,Izquierdo I,Blandina P,Provensi G

更新日期：2020-07-07 00:00:00

abstract：:This investigation was undertaken to determine the possible role of growth hormone (GH) in the hormonal regulation of hepatic low density lipoprotein (LDL) receptor expression. Treatment of normal rats with estrogen (ethynylestradiol, 5 mg/kg per day) increased the number of hepatic LDL receptors, and the LDL receptor...

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

authors： Rudling M,Norstedt G,Olivecrona H,Reihnér E,Gustafsson JA,Angelin B

更新日期：1992-08-01 00:00:00

abstract：:Endocytic protein trafficking is directed by sorting signals on cargo molecules that are recognized by cytosolic adaptor proteins. However, the steps necessary to segregate the variety of cargoes during endocytosis remain poorly defined. Using Caenorhabditis elegans, we demonstrate that multiple plasma membrane endocy...

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

authors： Mayers JR,Wang L,Pramanik J,Johnson A,Sarkeshik A,Wang Y,Saengsawang W,Yates JR 3rd,Audhya A

更新日期：2013-07-16 00:00:00

abstract：:Calmodulin (CaM) is a second messenger protein that has evolved to bind tightly to a variety of targets and, as such, exhibits low binding specificity. We redesigned CaM by using a computational protein design algorithm to improve its binding specificity for one of its targets, smooth muscle myosin light chain kinase ...

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

authors： Shifman JM,Mayo SL

更新日期：2003-11-11 00:00:00

abstract：:mAbs against tumor-associated carbohydrate antigens have the potential to play a prominent role in cancer immunotherapy. However, it has not been possible to fully exploit the clinical utility of such antibodies primarily, because those of adequate affinity could be derived only from murine sources. To address this pr...

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

authors： Mao S,Gao C,Lo CH,Wirsching P,Wong CH,Janda KD

更新日期：1999-06-08 00:00:00

abstract：:Polyploidy, which results from whole genome duplication (WGD), has shaped the long-term evolution of eukaryotic genomes in all kingdoms. Polyploidy is also implicated in adaptation, domestication, and speciation. Yet when WGD newly occurs, the resulting neopolyploids face numerous challenges. A particularly pernicious...

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

authors： Morgan C,Zhang H,Henry CE,Franklin FCH,Bomblies K

更新日期：2020-04-21 00:00:00

abstract：:Cultured skin fibroblasts from patients with Menkes disease, an X-linked disorder involving a defect in copper metabolism, were analyzed for copper concentration by means of atomic absorption spectrophotometry. These cultures consistently exhibited elevated copper concentrations (mean = 335.5 ng of copper per mg of pr...

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

authors： Goka TJ,Stevenson RE,Hefferan PM,Howell RR

更新日期：1976-02-01 00:00:00

abstract：:Systemic inflammation occurring around the course of tumor progression and treatment are often correlated with adverse oncological outcomes. As such, it is suspected that neutrophils, the first line of defense against infection, may play important roles in linking inflammation and metastatic seeding. To decipher the d...

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

authors： Chen MB,Hajal C,Benjamin DC,Yu C,Azizgolshani H,Hynes RO,Kamm RD

更新日期：2018-07-03 00:00:00

abstract：:Dead and dying cells release nucleic acids. These extracellular RNAs and DNAs can be taken up by inflammatory cells and activate multiple nucleic acid-sensing toll-like receptors (TLR3, 7, 8, and 9). The inappropriate activation of these TLRs can engender a variety of inflammatory and autoimmune diseases. The redundan...

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

authors： Lee J,Sohn JW,Zhang Y,Leong KW,Pisetsky D,Sullenger BA

更新日期：2011-08-23 00:00:00

abstract：:Since their discovery as key regulators of early animal development, microRNAs now are recognized as widespread regulators of gene expression. Despite their abundance, little is known regarding the regulation of microRNA biogenesis. We show that three highly conserved muscle-specific microRNAs, miR-1, miR-133 and miR-...

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

authors： Rao PK,Kumar RM,Farkhondeh M,Baskerville S,Lodish HF

更新日期：2006-06-06 00:00:00

abstract：:Groups of subjects with different degrees of glucose intolerance were examined in order to determine, first, the capacity of the beta cells to release insulin upon glucose stimulation and, second, sensitivity to insulin. The groups were selected on the basis of fasting blood glucose value and tolerances to oral and in...

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

authors： Efendić S,Wajngot A,Cerasi E,Luft R

更新日期：1980-12-01 00:00:00