Enteroendocrine precursors differentiate independently of Wnt and form serotonin expressing adenomas in response to active beta-catenin.

abstract：:Wnt/beta-catenin signaling controls various cell fates in metazoan development and is misregulated in several cancers and developmental disorders. Binding of a Wnt ligand to its transmembrane coreceptors inhibits phosphorylation and degradation of the transcriptional coactivator beta-catenin, which then translocates t...

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

authors： Cselenyi CS,Jernigan KK,Tahinci E,Thorne CA,Lee LA,Lee E

更新日期：2008-06-10 00:00:00

abstract：:Saccharomyces cerevisiae translation initiation factor eIF-4A, an RNA helicase of the Asp-Glu-Ala-Asp (DEAD) box protein family, was mutated in the putative ATP binding site and expressed in Escherichia coli. Mutant proteins with alanine at position 66 replaced by glycine [eIF-4A(A66G)] or valine [eIF-4A(A66V)] were p...

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

authors： Blum S,Schmid SR,Pause A,Buser P,Linder P,Sonenberg N,Trachsel H

更新日期：1992-08-15 00:00:00

abstract：:Nonribosomal peptide synthetases (NRPSs) usually catalyze the biosynthesis of peptide natural products by sequential selection, activation, and condensation of amino acid precursors. It was reported that some fatty acids, α-ketoacids, and α-hydroxyacids originating from amino acid metabolism as well as polyketide-deri...

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

authors： Peng C,Pu JY,Song LQ,Jian XH,Tang MC,Tang GL

更新日期：2012-05-29 00:00:00

abstract：:p53 is a master regulatory, sequence-specific transcription factor that directly controls expression of over 100 genes in response to various stress signals. Transactivation is generally considered to occur through p53 binding to a consensus response element (RE) composed of two 5'-RRRCWWGYYY-3' decamers. Recently, st...

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

authors： Menendez D,Inga A,Resnick MA

更新日期：2010-01-26 00:00:00

abstract：:To study the permanency of response to selection for a quantitative character in finite populations and the nature of the genetic effects that contribute to this response, we have used the covariance between ancestors and descendents within populations. Effects and variances are defined for an initial equilibrium rand...

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

authors： Cockerham CC,Tachida H

更新日期：1988-03-01 00:00:00

abstract：:This article discusses some of the similarities between work being done by economists and by physicists seeking to contribute to economics. We also mention some of the differences in the approaches taken and seek to justify these different approaches by developing the argument that by approaching the same problem from...

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

authors： Stanley HE,Amaral LA,Buldyrev SV,Gopikrishnan P,Plerou V,Salinger MA

更新日期：2002-02-19 00:00:00

abstract：:Incorporation and conversion of icosapentaenoic acid (20:5, n - 3) by human polymorphonuclear leukocytes were studied in volunteers (n = 6) ingesting a normal Western diet supplemented with icosapentaenoic acid (approximately equal to 4 g daily). Ingestion of icosapentaenoic acid leads to formation of biologically les...

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

authors： Strasser T,Fischer S,Weber PC

更新日期：1985-03-01 00:00:00

abstract：:Proteases constitute the largest enzyme family, yet their biological roles are obscured by our rudimentary understanding of their cellular substrates. There are 12 human caspases that play crucial roles in inflammation and cell differentiation and drive the terminal stages of cell death. Recent N-terminomics technolog...

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

authors： Julien O,Zhuang M,Wiita AP,O'Donoghue AJ,Knudsen GM,Craik CS,Wells JA

更新日期：2016-04-05 00:00:00

abstract：:Horizontal cells of the carp retina possess dopamine receptors linked to adenylate cyclase. Isolated, intact horizontal cells respond to micromolar concentrations of dopamine, whereas nanomolar concentrations of haloperidol, (+)-butaclamol, and flupenthixol block the dopamine response. Preincubation in Ringer's soluti...

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

authors： Van Buskirk R,Dowling JE

更新日期：1982-05-01 00:00:00

abstract：:Interactions between swimming cells and surfaces are essential to many microbiological processes, from bacterial biofilm formation to human fertilization. However, despite their fundamental importance, relatively little is known about the physical mechanisms that govern the scattering of flagellated or ciliated cells ...

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

authors： Kantsler V,Dunkel J,Polin M,Goldstein RE

更新日期：2013-01-22 00:00:00

abstract：:A high-pressure investigation of the Xe*H(2)O chemical system was conducted by using diamond-anvil cell techniques combined with in situ Raman spectroscopy, synchrotron x-ray diffraction, and laser heating. Structure I xenon clathrate was observed to be stable up to 1.8 GPa, at which pressure it transforms to a new Xe...

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

authors： Sanloup C,Mao Hk HK,Hemley RJ

更新日期：2002-01-08 00:00:00

abstract：:Intergroup conflict is a persistent feature of many human societies yet little is known about why individuals participate when doing so imposes a mortality risk. To evaluate whether participation in warfare is associated with reproductive benefits, we present data on participation in small-scale livestock raids among ...

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

authors： Glowacki L,Wrangham R

更新日期：2015-01-13 00:00:00

abstract：:Alzheimer beta/A4 amyloid precursor protein (APP) has been suggested to play a central role in the pathogenesis of Alzheimer disease. We have measured the content of different species of APP holoprotein and carboxyl-terminal fragments in human brains from young individuals, nondemented aged individuals, and aged indiv...

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

authors： Nordstedt C,Gandy SE,Alafuzoff I,Caporaso GL,Iverfeldt K,Grebb JA,Winblad B,Greengard P

更新日期：1991-10-15 00:00:00

abstract：:We have used the 1.1 kilobases of the 5' upstream region of the platelet factor four (PF4) gene coupled to the prokaryotic beta-galactosidase gene to generate two lines of transgenic mice that express this construct. Studies of blood, bone marrow, spleen, and thymus reveal that platelets are the only circulating blood...

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

authors： Ravid K,Beeler DL,Rabin MS,Ruley HE,Rosenberg RD

更新日期：1991-02-15 00:00:00

abstract：:Four mouse POU domain genomic DNA clones--Brain-1, Brain-2, Brain-4, and Scip--and Brain-2 cDNA, which are expressed in adult brain, were cloned and the coding and noncoding regions of the genes were sequenced. The amino acid sequences of the four POU domains are highly conserved; sequences in other regions of the pro...

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

authors： Hara Y,Rovescalli AC,Kim Y,Nirenberg M

更新日期：1992-04-15 00:00:00

abstract：:Protein-DNA interactions were studied in vivo at the region containing a human DNA replication origin, located at the 3' end of the lamin B2 gene and partially overlapping the promoter of another gene, located downstream. DNase I treatment of nuclei isolated from both exponentially growing and nonproliferating HL-60 c...

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

authors： Dimitrova DS,Giacca M,Demarchi F,Biamonti G,Riva S,Falaschi A

更新日期：1996-02-20 00:00:00

abstract：:Plant mortality and birth rates are critical components of plant life history affecting the stability of plant populations and the ecosystems they form. Although allometric theory predicts that both plant birth and mortality rates should be size-dependent, this prediction has not yet been tested across plants ranging ...

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

authors： Marbà N,Duarte CM,Agustí S

更新日期：2007-10-02 00:00:00

abstract：:Photoperiodic control of flowering time is believed to affect latitudinal distribution of plants. The blue light receptor CRY2 regulates photoperiodic flowering in the experimental model plant Arabidopsis thaliana. However, it is unclear whether genetic variations affecting cryptochrome activity or expression is broad...

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

authors： Zhang Q,Li H,Li R,Hu R,Fan C,Chen F,Wang Z,Liu X,Fu Y,Lin C

更新日期：2008-12-30 00:00:00

abstract：:Membrane contact sites (MCSs) in eukaryotic cells are hotspots for lipid exchange, which is essential for many biological functions, including regulation of membrane properties and protein trafficking. Lipid transfer proteins anchored at membrane contact sites (LAMs) contain sterol-specific lipid transfer domains [StA...

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

authors： Tong J,Manik MK,Im YJ

更新日期：2018-01-30 00:00:00

abstract：:We previously found that a minor fraction of single-stranded DNA (ss-DNA) isolated from native nuclear DNA of normal chicken embryonic cells and cells of other species hybridized with bulk nuclear DNA or cellular RNA in great excess. At least one-third of ss-DNA belonging to the nonrepetitious part of the cell genome ...

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

authors： Leibovitch SA,Tapiero H,Harel J

更新日期：1977-09-01 00:00:00

abstract：:The effect of reflex splanchnic nerve stimulation on proenkephalin A biosynthesis was investigated in the rat adrenal medulla. Tissue levels of native [Met5]enkephalin-like immunoreactivity (IR) (measured by direct RIA of tissue extracts), cryptic [Met5]enkephalin-like IR (calculated as the increase in [Met5]enkephali...

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

authors： Kanamatsu T,Unsworth CD,Diliberto EJ Jr,Viveros OH,Hong JS

更新日期：1986-12-01 00:00:00

abstract：:Copper is an essential micronutrient that plays a central role for a broad range of biological processes. Although there is compelling evidence that the intracellular milieu does not contain any free copper ions, the rapid kinetics of copper uptake and release suggests the presence of a labile intracellular copper poo...

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

authors： Yang L,McRae R,Henary MM,Patel R,Lai B,Vogt S,Fahrni CJ

更新日期：2005-08-09 00:00:00

abstract：:Sensitive optical signal detection can often be confounded by the presence of a significant background, and, as such, predetection background suppression is substantively important for weak signal detection. In this paper, we present a novel optical structure design, termed surface-wave-enabled darkfield aperture (SWE...

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

authors： Zheng G,Cui X,Yang C

更新日期：2010-05-18 00:00:00

abstract：:Previous findings of intact remote autobiographical memory in patients with medial temporal lobe damage have been questioned on the grounds that the narrative recollections were impoverished and fact-like and that the methods were not sufficiently sensitive to detect an impairment. We adopted a newer method, the Autob...

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

authors： Kirwan CB,Bayley PJ,Galván VV,Squire LR

更新日期：2008-02-19 00:00:00

abstract：:Certain complex phenotypes appear repeatedly across diverse species due to processes of evolutionary conservation and convergence. In some contexts like developmental body patterning, there is increased appreciation that common molecular mechanisms underlie common phenotypes; these molecular mechanisms include highly ...

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

authors： Rittschof CC,Bukhari SA,Sloofman LG,Troy JM,Caetano-Anollés D,Cash-Ahmed A,Kent M,Lu X,Sanogo YO,Weisner PA,Zhang H,Bell AM,Ma J,Sinha S,Robinson GE,Stubbs L

更新日期：2014-12-16 00:00:00

abstract：:Focal adhesion kinase (FAK) is a nonreceptor tyrosine kinase involved in development and human disease, including cancer. It is currently thought that the four-point one, ezrin, radixin, moesin (FERM)-kinase domain linker, which contains autophosphorylation site tyrosine (Y) 397, is not required for in vivo FAK functi...

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

authors： Heim JB,Squirewell EJ,Neu A,Zocher G,Sominidi-Damodaran S,Wyles SP,Nikolova E,Behrendt N,Saunte DM,Lock-Andersen J,Gaonkar KS,Yan H,Sarkaria JN,Krendel M,van Deursen J,Sprangers R,Stehle T,Böttcher RT,Lee JH,Ordog T

更新日期：2017-04-11 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 maximum rate of expression of the lac operon is severely reduced in lac promoter mutants. Revertants of these mutations which produce higher levels of enzyme were isolated. Some of these revertants had lost sensitivity to catabolite repression and transient repression. The mutations responsible for these losses to...

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

authors： Silverstone AE,Arditti RR,Magasanik B

更新日期：1970-07-01 00:00:00

abstract：:Conformationally compromised oncogenic mutants of the tumor suppressor protein p53 can, in principle, be rescued by small molecules that bind the native, but not the denatured state. We describe a strategy for the rational search for such molecules. A nine-residue peptide, CDB3, which was derived from a p53 binding pr...

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

authors： Friedler A,Hansson LO,Veprintsev DB,Freund SM,Rippin TM,Nikolova PV,Proctor MR,Rüdiger S,Fersht AR

更新日期：2002-01-22 00:00:00

abstract：:The zinc finger protein LMO4 is overexpressed in a high proportion of breast carcinomas. Here, we report that overexpression of a mouse mammary tumor virus (MMTV)-Lmo4 transgene in the mouse mammary gland elicits hyperplasia and mammary intraepithelial neoplasia or adenosquamous carcinoma in two transgenic strains wit...

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

authors： Sum EY,Segara D,Duscio B,Bath ML,Field AS,Sutherland RL,Lindeman GJ,Visvader JE

更新日期：2005-05-24 00:00:00