Science, health, and cultural literacy in a rapidly changing communications landscape.

abstract：:Metagenomics is expanding our knowledge of the gene content, functional significance, and genetic variability in natural microbial communities. Still, there exists limited information concerning the regulation and dynamics of genes in the environment. We report here global analysis of expressed genes in a naturally oc...

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

authors： Frias-Lopez J,Shi Y,Tyson GW,Coleman ML,Schuster SC,Chisholm SW,Delong EF

更新日期：2008-03-11 00:00:00

abstract：:We developed a method for rapidly generating thermostable enzyme variants. Our strategy is to introduce the gene coding for a given enzyme from a mesophilic organism into a thermophile, Bacillus stearothermophilus. Variants that retain the enzymatic activity at the higher growth temperatures of the thermophile are the...

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

authors： Liao H,McKenzie T,Hageman R

更新日期：1986-02-01 00:00:00

abstract：:The DNA-binding domain of c-Myb consists of three homologous tandem repeats of 52 amino acids. The structure of the third (C-terminal) repeat obtained by NMR analysis has a conformation related to the helix-turn-helix motif. To identify the role of each repeat in the sequence recognition of DNA, we analyzed specific i...

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

authors： Tanikawa J,Yasukawa T,Enari M,Ogata K,Nishimura Y,Ishii S,Sarai A

更新日期：1993-10-15 00:00:00

abstract：:Previous studies have established that humans and monkeys with damage to striate cortex are able to detect and localize bright targets within the resultant scotoma. Electrophysiological evidence in monkeys suggests that residual vision also might include sensitivity to direction of visual motion. We tested whether mac...

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

authors： Moore T,Rodman HR,Gross CG

更新日期：2001-01-02 00:00:00

abstract：:I summarize recent computational and experimental work that addresses the inherent variability in the synaptic and intrinsic conductances in normal healthy brains and shows that multiple solutions (sets of parameters) can produce similar circuit performance. I then discuss a number of issues raised by this observation...

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

authors： Marder E

更新日期：2011-09-13 00:00:00

abstract：:We investigate the problem of learning to play the game of rock-paper-scissors. Each player attempts to improve her/his average score by adjusting the frequency of the three possible responses, using reinforcement learning. For the zero sum game the learning process displays Hamiltonian chaos. Thus, the learning traje...

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

authors： Sato Y,Akiyama E,Farmer JD

更新日期：2002-04-02 00:00:00

abstract：:Zn2+ is critical for the functional and structural integrity of cells and contributes to a number of important processes including gene expression. It has been shown that NO exogenously applied via NO donors resulting in nitrosative stress leads to cytoplasmic Zn2+ release from the zinc storing protein metallothionein...

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

authors： Spahl DU,Berendji-Grün D,Suschek CV,Kolb-Bachofen V,Kröncke KD

更新日期：2003-11-25 00:00:00

abstract：:Calcium oxalate monohydrate (COM), which plays a functional role in plant physiology, is a source of chronic human disease, forming the major inorganic component of kidney stones. Understanding molecular mechanisms of biological control over COM crystallization is central to development of effective stone disease ther...

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

authors： Qiu SR,Wierzbicki A,Orme CA,Cody AM,Hoyer JR,Nancollas GH,Zepeda S,De Yoreo JJ

更新日期：2004-02-17 00:00:00

abstract：:The betaalpha barrel is the common protein fold of numerous enzymes and was proposed recently to be the result of gene duplication and fusion of an ancient half-barrel. The initial enzyme of shikimate biosynthesis possesses the additional feature of feedback regulation. The crystal structure and kinetic studies on chi...

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

authors： Hartmann M,Schneider TR,Pfeil A,Heinrich G,Lipscomb WN,Braus GH

更新日期：2003-02-04 00:00:00

abstract：:Recent studies have shown that the genes of the gibberellin (GA) biosynthesis pathway in the fungus Gibberella fujikuroi are organized in a cluster of at least seven genes. P450-1 is one of four cytochrome P450 monooxygenase genes in this cluster. Disruption of the P450-1 gene in the GA-producing wild-type strain IMI ...

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

authors： Rojas MC,Hedden P,Gaskin P,Tudzynski B

更新日期：2001-05-08 00:00:00

abstract：:B-1a cells reside in both the peritoneal cavity and the spleen. LPS stimulates splenic B-1a to differentiate to plasma cells producing natural IgM specific for microbial and self antigens. However, there are conflicting views as to whether the B-1a cells divide before this differentiation occurs, and hence how the res...

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

authors： Yang Y,Tung JW,Ghosn EE,Herzenberg LA,Herzenberg LA

更新日期：2007-03-13 00:00:00

abstract：:When histones in chromatin core particles were crosslinked with dimethylsuberimidate, the resulting particles had properties closely similar to those of native core particles. A crosslinked octameric histone complex was isolated from these particles under nondenaturing conditions. Upon reaction with DNA, this octameri...

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

authors： Stein A,Bina-Stein M,Simpson RT

更新日期：1977-07-01 00:00:00

abstract：:Methods are described for the removal of the sporophytic pollen grain coating of Brassica oleracea and for the isolation of coat polypeptides. The coat contains a small number of proteins ranging from 6 to 45 kDa. Many of the larger proteins are glycosylated, while all carry high positive charges resulting in pI value...

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

authors： Doughty J,Hedderson F,McCubbin A,Dickinson H

更新日期：1993-01-15 00:00:00

abstract：:An invariant substructure that forms two interlocked pairs of neighboring beta-strands occurs in essentially all known sandwich-like proteins. Eight conserved positions in these strands were recently shown to act as structural determinants. To test whether the residues at these invariant positions are conserved for me...

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

authors： Wilson CJ,Wittung-Stafshede P

更新日期：2005-03-15 00:00:00

abstract：:Maintenance of genomic stability is essential for normal organismal development and is vital to prevent diseases such as cancer. As genetic information is packaged into chromatin, it has become increasingly clear that the chromatin environment plays an important role in DNA damage response. However, how DNA repair is ...

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

authors： Li X,Liu L,Yang S,Song N,Zhou X,Gao J,Yu N,Shan L,Wang Q,Liang J,Xuan C,Wang Y,Shang Y,Shi L

更新日期：2014-05-13 00:00:00

abstract：:Coagulation factor V is a high molecular weight plasma glycoprotein that participates as a cofactor in the conversion of prothrombin to thrombin by factor Xa. A phage lambda gt11 Hep G2 cell cDNA expression library was screened by using an affinity-purified antibody to human factor V, and 11 positive clones were isola...

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

authors： Kane WH,Davie EW

更新日期：1986-09-01 00:00:00

abstract：:Two additional peptides with inhibin-like activity have been isolated from human seminal plasma. One consists of 52 amino acids and the other, 92 amino acids. They are designated alpha-inhibin-52 and alpha-inhibin-92. Sequence analyses show that the NH2-terminal 31 amino acids of alpha-inhibin-52 are identical to the ...

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

authors： Li CH,Hammonds RG Jr,Ramasharma K,Chung D

更新日期：1985-06-01 00:00:00

abstract：:The Notch signaling pathway is essential for many aspects of development, cell fate determination, and tissue homeostasis. Notch signaling can be modulated by posttranslational modifications to the Notch receptor, which are known to alter both ligand binding and receptor activation. We have modified the ligand-binding...

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

authors： Taylor P,Takeuchi H,Sheppard D,Chillakuri C,Lea SM,Haltiwanger RS,Handford PA

更新日期：2014-05-20 00:00:00

abstract：:Viperin is an IFN-inducible radical S-adenosylmethionine (SAM) enzyme that inhibits viral replication. We determined crystal structures of an anaerobically prepared fragment of mouse viperin (residues 45-362) complexed with S-adenosylhomocysteine (SAH) or 5'-deoxyadenosine (5'-dAdo) and l-methionine (l-Met). Viperin c...

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

authors： Fenwick MK,Li Y,Cresswell P,Modis Y,Ealick SE

更新日期：2017-06-27 00:00:00

abstract：:Parasitic plants share a common anatomical feature, the haustorium. Haustoria enable both infection and nutrient transfer, which often leads to growth penalties for host plants and yield reduction in crop species. Haustoria also reciprocally transfer substances, such as RNA and proteins, from parasite to host, but the...

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

authors： Spallek T,Melnyk CW,Wakatake T,Zhang J,Sakamoto Y,Kiba T,Yoshida S,Matsunaga S,Sakakibara H,Shirasu K

更新日期：2017-05-16 00:00:00

abstract：:Single molecule studies, at constant force, of the separation of double-stranded DNA into two separated single strands may provide information relevant to the dynamics of DNA replication. At constant applied force, theory predicts that the unzipped length as a function of time is characterized by jumps during which th...

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

authors： Danilowicz C,Coljee VW,Bouzigues C,Lubensky DK,Nelson DR,Prentiss M

更新日期：2003-02-18 00:00:00

abstract：:2-[4-(3,4-Dichlorophenylureido)phenoxy]-2-methylpropionic acid, LR16, combines with two symmetrically related sites in the central cavity of deoxyhemoglobin, 20 A away from the binding site of 2,3-bisphosphoglycerate, and acts as an allosteric effector synergistic with 2,3-bisphosphoglycerate. LR16 (1 mM) raises P50, ...

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

authors： Lalezari I,Rahbar S,Lalezari P,Fermi G,Perutz MF

更新日期：1988-08-01 00:00:00

abstract：:With the increased popularity of zebrafish (Danio rerio) for mutagenesis studies, efficient methods for manipulation of its genome are needed. One approach is the use of a transposable element as a vector for gene transfer in this species. We report here the transformation of zebrafish and germ-line transmission of th...

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

authors： Fadool JM,Hartl DL,Dowling JE

更新日期：1998-04-28 00:00:00

abstract：:Patent ductus arteriosus (PDA) is a common congenital heart disease that results when the ductus arteriosus, a muscular artery, fails to remodel and close after birth. A syndromic form of this disorder, Char syndrome, is caused by mutation in TFAP2B, the gene encoding a neural crest-derived transcription factor. Estab...

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

authors： Mani A,Radhakrishnan J,Farhi A,Carew KS,Warnes CA,Nelson-Williams C,Day RW,Pober B,State MW,Lifton RP

更新日期：2005-02-22 00:00:00

abstract：:Tropical forest degradation emits carbon at a rate of approximately 0.5 Pgxy(-1), reduces biodiversity, and facilitates forest clearance. Understanding degradation drivers and patterns is therefore crucial to managing forests to mitigate climate change and reduce biodiversity loss. Putative patterns of degradation aff...

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

authors： Ahrends A,Burgess ND,Milledge SA,Bulling MT,Fisher B,Smart JC,Clarke GP,Mhoro BE,Lewis SL

更新日期：2010-08-17 00:00:00

abstract：:RNA transcription in Euglena gracilis chloroplasts has been characterized by hybridization of RNA from cells at different stages of chloroplast development to (3)H-labeled chloroplast DNA restriction endonuclease fragments. Chloroplast DNA was digested into five fragments of 53,000, 35,000, 25,000, 10,000, and 6900 ba...

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

authors： Chelm BK,Hallick RB,Gray PW

更新日期：1979-05-01 00:00:00

abstract：:Astrocyte-elevated gene-1 (AEG-1) expression is increased in multiple cancers and plays a central role in Ha-ras-mediated oncogenesis through the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Additionally, overexpression of AEG-1 protects primary and transformed human and rat cells from serum starvation-...

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

authors： Emdad L,Lee SG,Su ZZ,Jeon HY,Boukerche H,Sarkar D,Fisher PB

更新日期：2009-12-15 00:00:00

abstract：:The plasma iron turnover was measured in 19 normal subjects. A correlation was found between plasma iron concentration and plasma iron turnover. In addition to the turnover of 55Fe at normal plasma iron concentration (predominantly monoferric transferrin), a second turnover in which the labeled plasma was saturated wi...

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

authors： Skarberg K,Eng M,Huebers H,Marsaglia G,Finch C

更新日期：1978-03-01 00:00:00

abstract：:Large mandibular defects are clinically challenging to reconstruct due to the complex anatomy of the jaw and the limited availability of appropriate tissue for repair. We envision leveraging current advances in fabrication and biomaterials to create implantable devices that generate bone within the patients themselves...

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

authors： Tatara AM,Koons GL,Watson E,Piepergerdes TC,Shah SR,Smith BT,Shum J,Melville JC,Hanna IA,Demian N,Ho T,Ratcliffe A,van den Beucken JJJP,Jansen JA,Wong ME,Mikos AG

更新日期：2019-04-02 00:00:00

abstract：:Matrix metalloprotease type 9 (MMP-9) has been functionally implicated in VEGF activation, the induction and maintenance of chronic angiogenesis, and early stage tumor growth in a number of mouse models of cancer. In this article, we have identified two inflammatory cell types that are major sources of MMP-9 in the an...

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

authors： Nozawa H,Chiu C,Hanahan D

更新日期：2006-08-15 00:00:00