Genome of hepatitis B virus: restriction enzyme cleavage and structure of DNA extracted from Dane particles.

abstract：:The ability of bacteria to regulate gene expression in response to changes in cell density is termed quorum sensing. This behavior involves the synthesis and recognition of extracellular, hormone-like compounds known as autoinducers. Here we report the structure of an autoinducer synthase, LuxS from Bacillus subtilis,...

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

authors： Hilgers MT,Ludwig ML

更新日期：2001-09-25 00:00:00

abstract：:In the Burmese python (Python molurus), the rapid up-regulation of gastrointestinal (GI) function and morphology after feeding, and subsequent down-regulation on completing digestion, are expected to be mediated by GI hormones and neuropeptides. Hence, we examined postfeeding changes in plasma and tissue concentration...

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

authors： Secor SM,Fehsenfeld D,Diamond J,Adrian TE

更新日期：2001-11-20 00:00:00

abstract：:Negative cooperativity has been observed in CTP synthetase, an allosteric enzyme which contains a regulatory site. Thus, the same enzyme exhibits negative cooperativity for GTP (an effector) and glutamine (a substrate) and positive cooperativity for ATP and UTP (both substrates). In the process of the delineation of t...

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

authors： Levitzki A,Koshland DE Jr

更新日期：1969-04-01 00:00:00

abstract：:A highly purified fraction obtained from scrapie (263-K strain)-infected hamsters' brains by an alternative procedure without proteinase K treatment contained a protease-resistant form of the scrapie precursor protein (PrPSc) and infectivity of 9.9 +/- 0.7 log LD50/ml. Polyclonal antibodies produced against hamster sc...

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

authors： Safar J,Wang W,Padgett MP,Ceroni M,Piccardo P,Zopf D,Gajdusek DC,Gibbs CJ Jr

更新日期：1990-08-01 00:00:00

abstract：:Terrestrial solar UVB radiation ( approximately 295-320 nm) readily induces cyclobutane pyrimidine dimers (CPDs) in human skin DNA that result in characteristic mutations associated with nonmelanoma skin cancer. The proinflammatory cytokine TNFalpha is important in mouse skin chemical carcinogenesis and is thought to ...

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

authors： Walker SL,Young AR

更新日期：2007-11-27 00:00:00

abstract：:Albatrosses (Diomedeidae) do not occur in the North Atlantic Ocean today except as vagrants, although five species were present in the early Pliocene. No fossil breeding sites of albatrosses were known previously. The timing of extinction of albatrosses in the North Atlantic was likewise unknown. Deposits that formed ...

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

authors： Olson SL,Hearty PJ

更新日期：2003-10-28 00:00:00

abstract：:Brief visual experience causes rapid physiological changes in the visual cortex during early postnatal development. A possible mediator of these effects is the immediate early genes whose protein products are involved in the rapid response of neurons to transsynaptic stimulation. Here we report evidence that the level...

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

authors： Rosen KM,McCormack MA,Villa-Komaroff L,Mower GD

更新日期：1992-06-15 00:00:00

abstract：:The mechanisms regulating expression of mouse mammary tumor virus (MMTV)-encoded superantigens from the viral sag gene are largely unknown, due to problems with detection and quantification of these low-abundance proteins. To study the expression and regulation of the MMTV sag gene, we have developed a sensitive and q...

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

authors： Reuss FU,Coffin JM

更新日期：1995-09-26 00:00:00

abstract：:The apparatus of photosynthetic energy conversion in chloroplasts is quite well characterized with respect to structure and function. Light-driven electron transport in the thylakoid membrane is coupled to synthesis of ATP, used to drive energy-dependent metabolic processes in the stroma and the outer surface of the t...

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

authors： Spetea C,Hundal T,Lundin B,Heddad M,Adamska I,Andersson B

更新日期：2004-02-03 00:00:00

abstract：:The rapid worldwide spread of severe acute respiratory syndrome demonstrated the potential threat an infectious disease poses in a closely interconnected and interdependent world. Here we introduce a probabilistic model that describes the worldwide spread of infectious diseases and demonstrate that a forecast of the g...

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

authors： Hufnagel L,Brockmann D,Geisel T

更新日期：2004-10-19 00:00:00

abstract：:Nitroxyl anion (HNONO(-)), the one-electron reduced form of nitric oxide (NO), induces positive cardiac inotropy and selective venodilation in the normal in vivo circulation. Here we tested whether HNO/NO(-) augments systolic and diastolic function of failing hearts, and whether contrary to NO/nitrates such modulation...

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

authors： Paolocci N,Katori T,Champion HC,St John ME,Miranda KM,Fukuto JM,Wink DA,Kass DA

更新日期：2003-04-29 00:00:00

abstract：:Degeneracy, the ability of elements that are structurally different to perform the same function or yield the same output, is a well known characteristic of the genetic code and immune systems. Here, we point out that degeneracy is a ubiquitous biological property and argue that it is a feature of complexity at geneti...

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

authors： Edelman GM,Gally JA

更新日期：2001-11-20 00:00:00

abstract：:In a search for a model cell system that might allow studies of the function of the Rho-related GTPase CDC42Hs in human cells, we measured the content and distribution of CDC42Hs in monocytes that were differentiating into macrophages. The total content of this protein increased 5- to 6-fold in phorbol ester-treated h...

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

authors： Aepfelbacher M,Vauti F,Weber PC,Glomset JA

更新日期：1994-05-10 00:00:00

abstract：:The mechanism by which antifreeze proteins (AFPs) irreversibly bind to ice has not yet been resolved. The ice-binding site of an AFP is relatively hydrophobic, but also contains many potential hydrogen bond donors/acceptors. The extent to which hydrogen bonding and the hydrophobic effect contribute to ice binding has ...

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

authors： Garnham CP,Campbell RL,Davies PL

更新日期：2011-05-03 00:00:00

abstract：:Xenopus laevis oocytes were injected with poly(A)+-mRNA isolated from chorionating follicular epithelium of the domesticated silk moth (Bombyx mori). On two-dimensional gel electrophoresis, the resultant translation products comigrated with authentic, secreted, chorion standards, demonstrating that the frog oocyte sys...

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

authors： Bock SC,Tiemeier DC,Mester K,Wu M,Goldsmith MR

更新日期：1982-02-01 00:00:00

abstract：:Bovine proinsulin has been crystallized under a variety of conditions at both neutral and acid pH. Microtechniques were employed with sample weights of about 200 mug and volumes of 5-20 mul. The crystalline preparations all differ from each other morphologically.X-ray photographs of one form, tetragonal bipyramids gro...

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

authors： Fullerton WW,Potter R,Low BW

更新日期：1970-08-01 00:00:00

abstract：:Formulas are derived for the effect of size on a free-swimming microbe's ability to follow chemical, light, or temperature stimuli or to disperse in random directions. The four main assumptions are as follows: (i) the organisms can be modeled as spheres, (ii) the power available to the organism for swimming is proport...

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

authors： Dusenbery DB

更新日期：1997-09-30 00:00:00

abstract：:The NMR structures of three single-amino acid variants of the C-terminal domain of the human prion protein, hPrP(121-230), are presented. In hPrP(M166V) and hPrP(R220K) the substitution is with the corresponding residue in murine PrP, and in hPrP(S170N) it is with the corresponding Syrian hamster residue. All three su...

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

authors： Calzolai L,Lysek DA,Guntert P,von Schroetter C,Riek R,Zahn R,Wüthrich K

更新日期：2000-07-18 00:00:00

abstract：:Classical studies suggest that high-level cognitive decisions (e.g., choosing between financial options) are suboptimal. In contrast, low-level decisions (e.g., choosing where to put your feet on a rocky ridge) appear near-optimal: the perception-cognition gap. Moreover, in classical tasks, people appear to put too mu...

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

authors： Jarvstad A,Hahn U,Rushton SK,Warren PA

更新日期：2013-10-01 00:00:00

abstract：:We demonstrate that the receptor binding moiety of Escherichia coli heat-labile enterotoxin (EtxB) can completely prevent autoimmune disease in a murine model of arthritis. Injection of male DBA/1 mice at the base of the tail with type II collagen in the presence of complete Freund's adjuvant normally leads to arthrit...

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

authors： Williams NA,Stasiuk LM,Nashar TO,Richards CM,Lang AK,Day MJ,Hirst TR

更新日期：1997-05-13 00:00:00

abstract：:Phage phi 29 DNA cannot be phosphorylated with polynucleotide kinase and [gamma-32P]ATP because of the presence of a viral protein covalently linked to the 5' termini. The 5' ends can, however, be made susceptible to phosphorylation by treatment with alkali and alkaline phosphatase. Restriction fragments Hpa II C and ...

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

authors： Escarmís C,Salas M

更新日期：1981-03-01 00:00:00

abstract：:The switch from membrane-bound to secreted IgM is accomplished by producing alternative forms of mRNA from a single mu heavy-chain gene. This process might be controlled at any of three steps--transcription termination, RNA splicing, or RNA cleavage/poly(A) addition. To distinguish between these possibilities, we have...

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

authors： Danner D,Leder P

更新日期：1985-12-01 00:00:00

abstract：:Complement receptors (CRs), expressed notably on myeloid and lymphoid cells, play an essential function in the elimination of complement-opsonized pathogens and apoptotic/necrotic cells. In addition, these receptors are crucial for the cross-talk between the innate and adaptive branches of the immune system. CR3 (also...

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

authors： Bajic G,Yatime L,Sim RB,Vorup-Jensen T,Andersen GR

更新日期：2013-10-08 00:00:00

abstract：:An increasing number of protein structures are found to encompass multiple folding nuclei, allowing their structures to be formed by several competing pathways. A typical example is the ribosomal protein S6, which comprises two folding nuclei (sigma1 and sigma2) defining two competing pathways in the folding energy la...

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

authors： Haglund E,Lind J,Oman T,Ohman A,Mäler L,Oliveberg M

更新日期：2009-12-22 00:00:00

abstract：:The Millennium Ecosystem Assessment (MA) introduced a new framework for analyzing social-ecological systems that has had wide influence in the policy and scientific communities. Studies after the MA are taking up new challenges in the basic science needed to assess, project, and manage flows of ecosystem services and ...

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

authors： Carpenter SR,Mooney HA,Agard J,Capistrano D,Defries RS,Díaz S,Dietz T,Duraiappah AK,Oteng-Yeboah A,Pereira HM,Perrings C,Reid WV,Sarukhan J,Scholes RJ,Whyte A

更新日期：2009-02-03 00:00:00

abstract：:The Ipl (Tssc3) gene lies in an extended imprinted region of distal mouse chromosome 7, which also contains the Igf2 gene. Expression of Ipl is highest in placenta and yolk sac, where its mRNA is derived almost entirely from the maternal allele. Ipl encodes a small cytoplasmic protein with a pleckstrin-homology (PH) d...

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

authors： Frank D,Fortino W,Clark L,Musalo R,Wang W,Saxena A,Li CM,Reik W,Ludwig T,Tycko B

更新日期：2002-05-28 00:00:00

abstract：:Evolutionary thinking can be applied to both cultural microevolution and macroevolution. However, much of the current literature focuses on cultural microevolution. In this article, we argue that the growing availability of large cross-cultural datasets facilitates the use of computational methods derived from evoluti...

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

authors： Gray RD,Watts J

更新日期：2017-07-25 00:00:00

abstract：:Recent genome-wide nucleosome mappings along with bioinformatics studies have confirmed that the DNA sequence plays a more important role in the collective organization of nucleosomes in vivo than previously thought. Yet in living cells, this organization also results from the action of various external factors like D...

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

authors： Milani P,Chevereau G,Vaillant C,Audit B,Haftek-Terreau Z,Marilley M,Bouvet P,Argoul F,Arneodo A

更新日期：2009-12-29 00:00:00

abstract：:Injection of antisense oligonucleotides was used to investigate the function of c-mos in murine oocytes. Oocytes injected with antisense c-mos oligonucleotides completed the first meiotic division but failed to initiate meiosis II. Instead, loss of c-mos function led to chromosome decondensation, reformation of a nucl...

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

authors： O'Keefe SJ,Wolfes H,Kiessling AA,Cooper GM

更新日期：1989-09-01 00:00:00

abstract：:The origins and consequences of a regulatory T cell (Treg) disorder in systemic lupus erythematosus (SLE) are poorly understood. In the (NZBxNZW) F(1) mouse model of lupus, we found that CD4(+)Foxp3(+) Treg failed to maintain a competitive pool size in the peripheral lymphoid organs resulting in a progressive homeosta...

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

authors： Humrich JY,Morbach H,Undeutsch R,Enghard P,Rosenberger S,Weigert O,Kloke L,Heimann J,Gaber T,Brandenburg S,Scheffold A,Huehn J,Radbruch A,Burmester GR,Riemekasten G

更新日期：2010-01-05 00:00:00