Evidence that an amoeba acquired a chloroplast by retaining part of an engulfed eukaryotic alga.

abstract：:The medial prefrontal cortex (mPFC) plays an essential role in regulating emotion, including inhibiting fear when danger has passed. The extinction of fear, however, is labile and a number of factors, including stress, cause extinguished fear to relapse. Here we show that fear relapse in rats limits single-unit activi...

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

authors： Giustino TF,Fitzgerald PJ,Ressler RL,Maren S

更新日期：2019-04-23 00:00:00

abstract：:Signaling through beta-arrestins is a recently appreciated mechanism used by seven-transmembrane receptors. Because G protein-coupled receptor kinase (GRK) phosphorylation of such receptors is generally a prerequisite for beta-arrestin binding, we studied the roles of different GRKs in promoting beta-arrestin-mediated...

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

authors： Ren XR,Reiter E,Ahn S,Kim J,Chen W,Lefkowitz RJ

更新日期：2005-02-01 00:00:00

abstract：:The T-box transcription factor TBX5 plays essential roles in cardiac and limb development. Various mutations in the TBX5 gene have been identified in patients with Holt-Oram syndrome, which is characterized by congenital defects in the heart and upper extremities. In this study, we identified a WW-domain-containing tr...

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

authors： Murakami M,Nakagawa M,Olson EN,Nakagawa O

更新日期：2005-12-13 00:00:00

abstract：:There is significant variation in the reported magnitude and even the sign of [Formula: see text] shifts in thin polymer films with nominally the same chemistry, film thickness, and supporting substrate. The implicit assumption is that methods used to estimate [Formula: see text] in bulk materials are relevant for inf...

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

authors： Zhang W,Douglas JF,Starr FW

更新日期：2018-05-29 00:00:00

abstract：:Linear double-stranded molecules of the circularly permuted and terminally redundant DNA of Salmonella bacteriophage P22 have been converted to oligomeric products in the presence of polynucleotide ligase coded for by the coliphage T4. The reaction has been monitored by sucrose density-gradient centrifugation and elec...

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

authors： Sgaramella V

更新日期：1972-11-01 00:00:00

abstract：:In insulin resistant states such as type 2 diabetes, there is a high demand on the β-cell to synthesize and secrete insulin, which challenges the ability of the endoplasmic reticulum (ER) to synthesize and fold nascent proteins. This creates a state of ER stress that triggers a coordinated program referred to as the u...

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

authors： Winnay JN,Dirice E,Liew CW,Kulkarni RN,Kahn CR

更新日期：2014-01-21 00:00:00

abstract：:The effect of metabolic depletion on the maturation-associated loss of membrane functions has been studied by using sheep reticulocytes incubated in vitro at 37 degrees C for periods up to 41 hr. ATP was either maintained with glucose, adenosine plus inosine, or depleted with 2-deoxyglucose plus arsenate. Two membrane...

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

authors： Weigensberg AM,Blostein R

更新日期：1983-08-01 00:00:00

abstract：:DNA from phi X174 is replicated in vitro with a fidelity similar to that found genetically. A mutation of TAG leads to TGG may be induced, however, by varying the concentrations of deoxynucleoside triphosphates, with a frequency proportional to [dGTP]2/[dATP]. This complex concentration dependence is consistent with t...

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

authors： Fersht AR

更新日期：1979-10-01 00:00:00

abstract：:Kss1, a yeast mitogen-activated protein kinase (MAPK), in its unphosphorylated (unactivated) state binds directly to and represses Ste12, a transcription factor necessary for expression of genes whose promoters contain filamentous response elements (FREs) and genes whose promoters contain pheromone response elements (...

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

authors： Bardwell L,Cook JG,Zhu-Shimoni JX,Voora D,Thorner J

更新日期：1998-12-22 00:00:00

abstract：:By Southern blotting and hybridization analysis using 32P-labeled poly(dT-dG) . poly(dC-dA) as a probe, we have found, in eukaryotic genomes, a huge number of stretches of dT-dG alternating sequence, a sequence that has been shown to adopt the Z-DNA conformation under some conditions. This sequence was found in all eu...

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

authors： Hamada H,Petrino MG,Kakunaga T

更新日期：1982-11-01 00:00:00

abstract：:Colloidal and sol-gel procedures have been used to prepare heterogeneous catalysts consisting of platinum metal particles with narrow size distributions and well defined shapes dispersed on high-surface-area silica supports. The overall procedure was developed in three stages. First, tetrahedral and cubic colloidal me...

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

authors： Lee I,Morales R,Albiter MA,Zaera F

更新日期：2008-10-07 00:00:00

abstract：:Plant germ cells develop in specialized haploid structures, termed gametophytes. The female gametophyte patterns of flowering plants are diverse, with often unknown adaptive value. Here we present the Arabidopsis fiona mutant, which forms a female gametophyte that is structurally and functionally reminiscent of a phyl...

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

authors： Kägi C,Baumann N,Nielsen N,Stierhof YD,Gross-Hardt R

更新日期：2010-12-21 00:00:00

abstract：:A sensitive in vitro crosslinking technique using a photoactive derivative of the chimeric activator LexA-E2F-1 was used to identify yeast proteins that might influence the response of RNA polymerase II to transcriptional activators. We found that a novel yeast protein, Xtc1p, could be covalently crosslinked to the ac...

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

authors： Emili A,Kobayashi R,Ingles CJ

更新日期：1998-09-15 00:00:00

abstract：:We report the direct measurement of thermodynamic properties of colloidal hard spheres by optical microscopy. By using confocal microscopy, we obtain three-dimensional snapshots of a colloidal hard-sphere suspension over a wide range of densities. From these snapshots, the available volume to insert an additional sphe...

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

authors： Dullens RP,Aarts DG,Kegel WK

更新日期：2006-01-17 00:00:00

abstract：:Oncogene-induced senescence (OIS) is an initial barrier to tumor development. Reactive oxygen species (ROS) is critical for oncogenic Ras OIS, but the downstream effectors to mediate ROS signaling are still relatively elusive. Senescent cells develop a senescence-associated secretory phenotype (SASP). However, the mec...

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

authors： Wang P,Han L,Shen H,Wang P,Lv C,Zhao G,Niu J,Xue L,Wang QJ,Tong T,Chen J

更新日期：2014-05-27 00:00:00

abstract：:The repeatability of evolutionary change is difficult to quantify because only a single outcome can usually be observed for any precise set of circumstances. In this study, however, we have quantified the frequency of parallel and divergent genetic changes in 12 initially identical populations of Escherichia coli that...

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

authors： Woods R,Schneider D,Winkworth CL,Riley MA,Lenski RE

更新日期：2006-06-13 00:00:00

abstract：:The total amount of noncoding sequences on chromosomes of contemporary organisms varies significantly from species to species. We propose a hypothesis for the origin of these noncoding sequences that assumes that (i) an approximately equal to 0.55-kilobase (kb)-long reading frame composed the primordial gene and (ii) ...

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

authors： Naora H,Miyahara K,Curnow RN

更新日期：1987-09-01 00:00:00

abstract：:Cellular metabolism alters patterns of gene expression through a variety of mechanisms, including alterations in histone modifications and transcription factor activity. Nicotinamide adenine dinucleotide (NAD)-dependent proteins such as poly(ADP ribose) polymerases (PARPs) and sirtuin deacetylases play important roles...

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

authors： Chang J,Zhang B,Heath H,Galjart N,Wang X,Milbrandt J

更新日期：2010-12-14 00:00:00

abstract：:Depending on the cellular context, BCL2-like proteins promote mitochondrial fusion or fission. What determines which of these two opposing processes they promote has so far been unknown. Furthermore, the mechanisms through which BCL2-like proteins affect mitochondrial dynamics remain to be fully understood. The BCL2-l...

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

authors： Lu Y,Rolland SG,Conradt B

更新日期：2011-10-11 00:00:00

abstract：:Nerve growth factor has been quantified by both bioassay and radial immunodiffusion in mouse saliva elicited by several secretagogues. The concentrations by bioassay of nerve growth factor in both epinephrine- and norepinephrine-induced saliva (3400 and 900 mug/ml, respectively) are higher than reported in any other s...

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

authors： Wallace LJ,Partlow LM

更新日期：1976-11-01 00:00:00

abstract：:Whereas the importance of macrophages in chronic inflammatory diseases is well recognized, there is an increasing awareness that neutrophils may also play an important role. In addition to the well-documented heterogeneity of macrophage phenotypes and functions, neutrophils also show remarkable phenotypic diversity am...

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

authors： Weiss M,Byrne AJ,Blazek K,Saliba DG,Pease JE,Perocheau D,Feldmann M,Udalova IA

更新日期：2015-09-01 00:00:00

abstract：:Tc1-like transposable elements from teleost fish have been phylogenetically examined to determine the mechanisms involved in their evolution and conserved domains of function. We identified two new functional domains in these elements. The first is a bipartite nuclear localization signal, indicating that transposons c...

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

authors： Ivics Z,Izsvak Z,Minter A,Hackett PB

更新日期：1996-05-14 00:00:00

abstract：:By use of the indirect peroxidase-antiperoxidase complex immunocytochemical technique, antibody to purified human renal renin was applied to formalin-fixed paraffin sections of human cadaver brain. Immune reaction products were observed in most nerve cells in all areas of the brain examined; staining was limited to th...

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

authors： Slater EE,Defendini R,Zimmerman EA

更新日期：1980-09-01 00:00:00

abstract：:Heparin is the most widely prescribed biopharmaceutical in production globally. Its potent anticoagulant activity and safety makes it the drug of choice for preventing deep vein thrombosis and pulmonary embolism. In 2008, adulterated material was introduced into the heparin supply chain, resulting in several hundred d...

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

authors： Weiss RJ,Spahn PN,Toledo AG,Chiang AWT,Kellman BP,Li J,Benner C,Glass CK,Gordts PLSM,Lewis NE,Esko JD

更新日期：2020-04-28 00:00:00

abstract：:The current epidemic of infections caused by antibiotic-resistant gram-positive bacteria requires the discovery of new drug targets and the development of new therapeutics. Lipoteichoic acid (LTA), a cell wall polymer of gram-positive bacteria, consists of 1,3-polyglycerol-phosphate linked to glycolipid. LTA synthase ...

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

authors： Richter SG,Elli D,Kim HK,Hendrickx AP,Sorg JA,Schneewind O,Missiakas D

更新日期：2013-02-26 00:00:00

abstract：:Loss or reduction in function of tumor suppressor genes contributes to tumorigenesis. Here, by allelic DNA copy number analysis using single-nucleotide polymorphism genotyping array and mass spectrometry, we report homozygous deletion in glioblastoma multiformes at chromosome 13q21, where DACH1 gene is located. We fou...

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

authors： Watanabe A,Ogiwara H,Ehata S,Mukasa A,Ishikawa S,Maeda D,Ueki K,Ino Y,Todo T,Yamada Y,Fukayama M,Saito N,Miyazono K,Aburatani H

更新日期：2011-07-26 00:00:00

abstract：:Endothelium-derived relaxing factor (EDRF) activity has been attributed to the highly labile nitric oxide radical (NO). In view of the fact that the plasma and cellular milieux contain reactive species that can rapidly inactivate NO, it has been postulated that NO is stabilized by a carrier molecule that preserves its...

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

authors： Stamler JS,Simon DI,Osborne JA,Mullins ME,Jaraki O,Michel T,Singel DJ,Loscalzo J

更新日期：1992-01-01 00:00:00

abstract：:MicroRNAs (miRNAs) are a class of small noncoding RNAs that have important regulatory roles in multicellular organisms. The public miRNA database contains 321 human miRNA sequences, 234 of which have been experimentally verified. To explore the possibility that additional miRNAs are present in the human genome, we hav...

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

authors： Cummins JM,He Y,Leary RJ,Pagliarini R,Diaz LA Jr,Sjoblom T,Barad O,Bentwich Z,Szafranska AE,Labourier E,Raymond CK,Roberts BS,Juhl H,Kinzler KW,Vogelstein B,Velculescu VE

更新日期：2006-03-07 00:00:00

abstract：:The thymus lacks self-renewing hematopoietic cells, and thymopoiesis fails rapidly when the migration of progenitor cells to the thymus ceases. Hence, the process of thymus homing is an essential step for T-cell development and cellular immunity. Despite decades of research, the molecular details of thymus homing have...

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

authors： Calderón L,Boehm T

更新日期：2011-05-03 00:00:00

abstract：:E2F is a heterodimeric transcription factor that regulates the expression of genes at the G1/S boundary and is composed of two related but distinct families of proteins, E2F and DP. E2F/DP heterodimers form complexes with the retinoblastoma (Rb) protein, the Rb-related proteins p107 and p130, and cyclins/cdks in a cel...

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

authors： Rogers KT,Higgins PD,Milla MM,Phillips RS,Horowitz JM

更新日期：1996-07-23 00:00:00