Analysis of a Drosophila amplicon in follicle cells highlights the diversity of metazoan replication origins.

abstract：:Plant phylogenetic estimates are most likely to be reliable when congruent evidence is obtained independently from the mitochondrial, plastid, and nuclear genomes with all methods of analysis. Here, results are presented from separate and combined genomic analyses of new and previously published data, including six an...

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

authors： Barkman TJ,Chenery G,McNeal JR,Lyons-Weiler J,Ellisens WJ,Moore G,Wolfe AD,dePamphilis CW

更新日期：2000-11-21 00:00:00

abstract：:Distinct subsets of thymic epithelial cells (TECs) support T-cell development and selection. Isolated TECs contain multicellular complexes that enclose many viable thymocytes. However, the functions of those TECs, termed thymic nurse cells (TNCs), are unclear and the idea that TNCs are present in vivo is questioned. H...

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

authors： Nakagawa Y,Ohigashi I,Nitta T,Sakata M,Tanaka K,Murata S,Kanagawa O,Takahama Y

更新日期：2012-12-11 00:00:00

abstract：:Studies to elucidate the mode of action of aldosterone have been carried out in the amphibian urinary bladder. The following previously reported hypotheses were evaluated: (1) aldosterone stimulates sodium transport by increasing the amount of sodium available to the sodium pump; (2) aldosterone enhances energy produc...

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

authors： Goodman DB,Allen JE,Rasmussen H

更新日期：1969-09-01 00:00:00

abstract：:Plants sense phosphate (Pi) deficiency and initiate signaling that controls adaptive responses necessary for Pi acquisition. Herein, evidence establishes that AtSIZ1 is a plant small ubiquitin-like modifier (SUMO) E3 ligase and is a focal controller of Pi starvation-dependent responses. T-DNA insertional mutated allel...

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

authors： Miura K,Rus A,Sharkhuu A,Yokoi S,Karthikeyan AS,Raghothama KG,Baek D,Koo YD,Jin JB,Bressan RA,Yun DJ,Hasegawa PM

更新日期：2005-05-24 00:00:00

abstract：:Fibrocytes are collagen-type-I-producing cells that arise at low frequency from hematopoietic cells. We have analyzed in mice which leukocyte subsets are required for generation of fibrocytes and show that murine fibrocytes develop from the subpopulation of CD11b(+) CD115(+) Gr1(+) monocytes under the control of CD4(+...

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

authors： Niedermeier M,Reich B,Rodriguez Gomez M,Denzel A,Schmidbauer K,Göbel N,Talke Y,Schweda F,Mack M

更新日期：2009-10-20 00:00:00

abstract：:The Kell blood group is a major antigenic system in human erythrocytes. Kell antigens reside on a 93-kDa membrane glycoprotein that is surface-exposed and associated with the underlying cytoskeleton. We isolated tryptic peptides and, based on the amino acid sequence of one of the peptides and by using the PCR, prepare...

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

authors： Lee S,Zambas ED,Marsh WL,Redman CM

更新日期：1991-07-15 00:00:00

abstract：:Alternative ribosome subunit proteins are prevalent in the genomes of diverse bacterial species, but their functional significance is controversial. Attempts to study microbial ribosomal heterogeneity have mostly relied on comparing wild-type strains with mutants in which subunits have been deleted, but this approach ...

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

authors： Chen YX,Xu ZY,Ge X,Sanyal S,Lu ZJ,Javid B

更新日期：2020-08-11 00:00:00

abstract：:Three components of differentiated muscle membrane, the acetylcholine receptor, acetylcholinesterase (EC 3.1.1.7; acetylcholine hydrolase), and adenylate cyclase [EC 4.6.1.1; ATP pyrophosphate-lyase (cyclizing)], appear simultaneously during myogenesis in cultures of embryonic chick muscle, after the main period of ra...

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

authors： Prives JM,Paterson BM

更新日期：1974-08-01 00:00:00

abstract：:We use the inverse scattering method to determine the weak limit of solutions of the Korteweg-deVries equation as dispersion tends to zero. The limit, valid for all time, is characterized in terms of a quadratic programming problem which can be solved with the aid of function theoretic methods. For large t, the soluti...

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

authors： Lax PD,Levermore CD

更新日期：1979-08-01 00:00:00

abstract：:Cancers frequently arise as a result of an acquired genomic instability and the subsequent clonal evolution of neoplastic cells with variable patterns of genetic aberrations. Thus, the presence and behaviors of distinct clonal populations in each patient's tumor may underlie multiple clinical phenotypes in cancers. We...

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

authors： Ruiz C,Lenkiewicz E,Evers L,Holley T,Robeson A,Kiefer J,Demeure MJ,Hollingsworth MA,Shen M,Prunkard D,Rabinovitch PS,Zellweger T,Mousses S,Trent JM,Carpten JD,Bubendorf L,Von Hoff D,Barrett MT

更新日期：2011-07-19 00:00:00

abstract：:Frame-shift mutations at microsatellites occur as a time-dependent function of polymerase errors followed by failure of postreplicational mismatch repair. A cell-culture system was developed that allows identification of intermediate mutant cells that carry the mutation on a single DNA strand after the initial DNA pol...

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

authors： Gasche C,Chang CL,Natarajan L,Goel A,Rhees J,Young DJ,Arnold CN,Boland CR

更新日期：2003-02-18 00:00:00

abstract：:A 6.1-kilobase insertion into the rudimentary (r) gene was cloned and partially sequenced. The insertion consists of a 703-base-pair (bp) P element next to a 5.4-kilobase single-copy sequence. The normal position of the single-copy sequence is near the tip of the X chromosome. Upon insertion into the r gene, this chim...

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

authors： Tsubota SI,Huong DV

更新日期：1991-02-01 00:00:00

abstract：:Eleven amino acid positions in the helix-turn-helix of lambda repressor have been mutagenized by using a combinatorial method in which alanine is substituted at each position with a probability of 0.5. Approximately 25% of the 2048 proteins in the resulting binomial library are active, including some variants with as ...

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

authors： Gregoret LM,Sauer RT

更新日期：1993-05-01 00:00:00

abstract：:Glutaredoxins (GRXs), also known as thioltransferases, use glutathione as a cofactor for reduction of disulfides in prokaryotes and eukaryotes. We demonstrate that the vaccinia virus O2L open reading frame encodes a functional GRX, as predicted by Johnson et al. [Johnson, G. P., Goebel, S. J., Perkus, M. E., Davis, S....

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

authors： Ahn BY,Moss B

更新日期：1992-08-01 00:00:00

abstract：:Circadian timekeeping by intracellular molecular clocks is evident widely in prokaryotes and eukaryotes. The clockworks are driven by autoregulatory feedback loops that lead to oscillating levels of components whose maxima are in fixed phase relationships with one another. These phase relationships are the key metric ...

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

authors： Mirsky HP,Liu AC,Welsh DK,Kay SA,Doyle FJ 3rd

更新日期：2009-07-07 00:00:00

abstract：:Dystrophic or ectopic mineral deposition occurs in many pathologic conditions, including atherosclerosis. Calcium mineral deposits that frequently accompany atherosclerosis are readily quantifiable radiographically, serve as a surrogate marker for the disease, and predict a higher risk of myocardial infarction and dea...

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

authors： Doherty TM,Asotra K,Fitzpatrick LA,Qiao JH,Wilkin DJ,Detrano RC,Dunstan CR,Shah PK,Rajavashisth TB

更新日期：2003-09-30 00:00:00

abstract：:The ability of beta cells to endure assaults may be relevant in the development of insulin-dependent diabetes mellitus. This study examines the susceptibility of human pancreatic islets to agents that are cytotoxic for rodent beta cells--i.e., sodium nitroprusside (NP, a nitric oxide donor), streptozotocin (SZ), or al...

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

authors： Eizirik DL,Pipeleers DG,Ling Z,Welsh N,Hellerström C,Andersson A

更新日期：1994-09-27 00:00:00

abstract：:A half-century's worth of research has established the existence of numerous event-related potential components measuring different cognitive operations in humans including the selection of stimuli by covert attention mechanisms. Surprisingly, it is unknown whether nonhuman primates exhibit homologous electrophysiolog...

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

authors： Woodman GF,Kang MS,Rossi AF,Schall JD

更新日期：2007-09-18 00:00:00

abstract：:IFN-gamma is well known as the signature cytokine of CD4+ T helper 1, CD8+, and natural killer cells, but recent studies demonstrate that antigen-presenting cells, in particular dendritic cells (DCs), are another potent source for this proinflammatory cytokine. T-bet, a transcription factor that controls IFN-gamma exp...

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

authors： Lugo-Villarino G,Maldonado-Lopez R,Possemato R,Penaranda C,Glimcher LH

更新日期：2003-06-24 00:00:00

abstract：:The type II cell of the alveolar epithelium of adult rats has been studied by electron microscopy to determine its ability to endocytose electron-dense tracers of differing molecular charge and size. The tracers studied were native (anionic) ferritin, cationic ferritin, 70-kilodalton dextran, and colloidal carbon. Alv...

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

authors： Williams MC

更新日期：1984-10-01 00:00:00

abstract：:A mol of creatine kinase (EC 2.7.3.2), an enzyme with two identical subunits can be titrated very rapidly and stoichiometrically with 2 mol of 2-chloromercuri-4-nitrophenol, an environmentally sensitive chromophoric probe specific for thiols. Chemical modification does not inactivate the enzyme nor can the reaction be...

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

authors： Quiocho FE,Thomson JW

更新日期：1973-10-01 00:00:00

abstract：:Granulocyte-colony stimulating factor (G-CSF) induces differentiation of M1 murine myeloid leukemia cells into mature granulocytes/macrophages and also causes accumulation of the cells in the G1 phase of the cell cycle. We examined, therefore, whether synchronization of M1 cells in the G1 phase could affect G-CSF-indu...

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

authors： Tsuda H,Neckers LM,Pluznik DH

更新日期：1986-06-01 00:00:00

abstract：:The mechanism of contrast enhancement of tumors using magnetic resonance imaging was investigated in MCF7 human breast cancer implanted in nude mice. Dynamic contrast-enhanced images recorded at high spatial resolution were analyzed by an image analysis method based on a physiological model, which included the blood c...

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

authors： Furman-Haran E,Margalit R,Grobgeld D,Degani H

更新日期：1996-06-25 00:00:00

abstract：:Experimental exclusion of the Andean flamingo (Phoenicoparrus andinus) from shallow water areas of a salt lake in the Bolivian Andes caused large increases in the biomass of microorganisms inhabiting the surface sediments, especially a large diatom (Surirella wetzeli), amebas, ciliates, and nematodes. This is a conser...

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

authors： Hurlbert SH,Chang CC

更新日期：1983-08-01 00:00:00

abstract：:Because of the rise in atmospheric oxygen 2.3 billion years ago (Gya) and the subsequent changes in oceanic redox state over the last 2.3-1 Gya, trace metal bioavailability in marine environments has changed dramatically. Although theorized to have influenced the biological usage of metals leaving discernable genomic ...

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

authors： Dupont CL,Yang S,Palenik B,Bourne PE

更新日期：2006-11-21 00:00:00

abstract：:Siderophores are essential factors for iron (Fe) acquisition in bacteria during colonization and infection of eukaryotic hosts, which restrain iron access through iron-binding protein, such as lactoferrin and transferrin. The synthesis of siderophores by Escherichia coli is considered to be fully regulated at the tran...

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

authors： Salvail H,Lanthier-Bourbonnais P,Sobota JM,Caza M,Benjamin JA,Mendieta ME,Lépine F,Dozois CM,Imlay J,Massé E

更新日期：2010-08-24 00:00:00

abstract：:Classification within the genus Pistacia has been based on leaf morphology and geographical distribution. Molecular genetic tools (PCR amplification followed by restriction analysis of a 3.2-kb region of variable chloroplast DNA, and restriction fragment length polymorphism analysis of the Pistacia cpDNA with tobacco ...

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

authors： Parfitt DE,Badenes ML

更新日期：1997-07-22 00:00:00

abstract：:The extracellular hemoglobin of Ascaris has an extremely high oxygen affinity (P50 = 0.004 mmHg). It consists of eight identical subunits of molecular weight 40,600. Their sequence, determined by protein chemistry, shows two tandemly linked globin-like sequences and an 18-residue C-terminal extension. Two N-linked gly...

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

authors： De Baere I,Liu L,Moens L,Van Beeumen J,Gielens C,Richelle J,Trotman C,Finch J,Gerstein M,Perutz M

更新日期：1992-05-15 00:00:00

abstract：:We have compared the behavior in solution of the synthetic polynucleotide poly(dG-m5dC).poly(dG-m5dC) with that of the unmethylated polynucleotide poly(dG-dC).poly(dG-dC). In solutions containing high concentrations of salt, poly(dG-dC).poly(dG-dC) is known to exhibit altered circular dichroic and absorption spectra c...

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

authors： Behe M,Felsenfeld G

更新日期：1981-03-01 00:00:00

abstract：:Intrinsically disordered proteins (IDPs) are involved in a wide range of regulatory processes in the cell. Owing to their flexibility, their conformations are expected to be particularly sensitive to the crowded cellular environment. Here we use single-molecule Förster resonance energy transfer to quantify the effect ...

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

authors： Soranno A,Koenig I,Borgia MB,Hofmann H,Zosel F,Nettels D,Schuler B

更新日期：2014-04-01 00:00:00