Genetic regulatory mechanisms and the ecological niche of Escherichia coli.

abstract：:Echolocating big brown bats (Eptesicus fuscus) broadcast ultrasonic frequency-modulated (FM) biosonar sounds (20-100 kHz frequencies; 10-50 microseconds periods) and perceive target range from echo delay. Knowing the acuity for delay resolution is essential to understand how bats process echoes because they perceive t...

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

authors： Simmons JA,Ferragamo MJ,Moss CF

更新日期：1998-10-13 00:00:00

abstract：:T cells are activated physiologically by triggering the T-cell receptor-CD3 complex. There is evidence that invariant accessory molecules on the T-cell membrane (CD8 and CD4) are involved in the major histocompatibility complex-restricted recognition process. Moreover, binding and crosslinking of these accessory molec...

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

authors： Samstag Y,Emmrich F,Staehelin T

更新日期：1988-12-01 00:00:00

abstract：:Calcicludine (CaC) is a 60-amino acid polypeptide from the venom of Dendroaspis angusticeps. It is structurally homologous to the Kunitz-type protease inhibitor, to dendrotoxins, which block K+ channels, and to the protease inhibitor domain of the amyloid beta protein that accumulates in Alzheimer disease. Voltage-cla...

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

authors： Schweitz H,Heurteaux C,Bois P,Moinier D,Romey G,Lazdunski M

更新日期：1994-02-01 00:00:00

abstract：:Infective stages of the protozoan parasite Leishmania spp. accumulate a class of beta-1,2-mannan oligosaccharides as their major carbohydrate reserve material. Here, we describe the biosynthesis of Leishmania mannan. Mannan precursors were identified by metabolic labeling of Leishmania mexicana promastigotes with [(3)...

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

authors： Sernee MF,Ralton JE,Dinev Z,Khairallah GN,O'Hair RA,Williams SJ,McConville MJ

更新日期：2006-06-20 00:00:00

abstract：:Proper regulation of the intracellular ion concentration is essential to maintain life and is achieved by ion transporters that transport their substrates across the membrane in a strictly regulated manner. MgtE is a Mg(2+) transporter that may function in the homeostasis of the intracellular Mg(2+) concentration. A r...

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

authors： Ishitani R,Sugita Y,Dohmae N,Furuya N,Hattori M,Nureki O

更新日期：2008-10-07 00:00:00

abstract：:The polypeptide chain initiation factor 2 (eIF-2) binds phospholipid (PL) and becomes a potent inhibitor of translation in hemin-supplemented reticulocyte lysates. This binding is markedly reduced by prior treatment of eIF-2 with N-ethylmaleimide. Although PL is probably bound by all three eIF-2 subunits, our results ...

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

authors： de Haro C,de Herreros AG,Ochoa S

更新日期：1986-09-01 00:00:00

abstract：:The constant heavy chain (CH1) domain affects antibody affinity and fine specificity, challenging the paradigm that only variable regions contribute to antigen binding. To investigate the role of the CH1 domain, we constructed IgA2 from the broadly neutralizing anti-HIV-1 2F5 IgG1, and compared 2F5 IgA2 and IgG bindin...

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

authors： Tudor D,Yu H,Maupetit J,Drillet AS,Bouceba T,Schwartz-Cornil I,Lopalco L,Tuffery P,Bomsel M

更新日期：2012-07-31 00:00:00

abstract：:We have used X-ray diffraction on the rhombohedral phospholipid phase to reconstruct stalk structures in different pure lipids and lipid mixtures with unprecedented resolution, enabling a quantitative analysis of geometry, as well as curvature and hydration energies. Electron density isosurfaces are used to study shap...

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

authors： Aeffner S,Reusch T,Weinhausen B,Salditt T

更新日期：2012-06-19 00:00:00

abstract：:Establishment of functional synaptic connections in a selective manner is essential for nervous system operation. In mammalian retinas, rod and cone photoreceptors form selective synaptic connections with different classes of bipolar cells (BCs) to propagate light signals. While there has been progress in elucidating ...

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

authors： Cao Y,Wang Y,Dunn HA,Orlandi C,Shultz N,Kamasawa N,Fitzpatrick D,Li W,Zeitz C,Hauswirth W,Martemyanov KA

更新日期：2020-09-22 00:00:00

abstract：:Toll-like receptors (TLRs) have been shown to participate in the recognition of pathogens by the innate immune system, but it is not clear how a restricted family of receptors has the capacity to recognize the wide spectrum of TLR stimuli known to exist. We report here that two members of the TLR family, TLR2 and TLR6...

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

authors： Ozinsky A,Underhill DM,Fontenot JD,Hajjar AM,Smith KD,Wilson CB,Schroeder L,Aderem A

更新日期：2000-12-05 00:00:00

abstract：:Studies on contact-inhibited mouse embryo fibroblast 3T3 cells and 3T3 cells transformed by oncogenic RNA and DNA viruses and by a chemical carcinogen have demonstrated differences in plasma membrane architecture. Spin-label and freeze-fracture ultrastructural studies have shown that contact-inhibited cells have order...

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

authors： Barnett RE,Furcht LT,Scott RE

更新日期：1974-05-01 00:00:00

abstract：:We have identified, cultured, characterized, and propagated adult pluripotent stem cells (PSC) from a subset of human peripheral blood monocytes. These cells, which in appearance resemble fibroblasts, expand in the presence of macrophage colony-stimulating factor and display monocytic and hematopoietic stem cell marke...

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

authors： Zhao Y,Glesne D,Huberman E

更新日期：2003-03-04 00:00:00

abstract：:Hyperphosphorylated α-synuclein in Lewy bodies and Lewy neurites is a characteristic neuropathological feature of Parkinson's disease (PD) and Dementia with Lewy bodies (DLB). The catalytic subunit of the specific phosphatase, protein phosphatase 2A (PP2A) that dephosphorylates α-synuclein, is hypomethylated in these ...

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

authors： Yan R,Zhang J,Park HJ,Park ES,Oh S,Zheng H,Junn E,Voronkov M,Stock JB,Mouradian MM

更新日期：2018-12-18 00:00:00

abstract：:Increasing interest in the role of the frontal lobe in relation to psychiatric and neurologic disorders has popularized tests of frontal function. One of these is the antisaccade task, in which both frontal lobe patients and schizophrenics are impaired despite normal performance on (pro)saccadic tasks. We used positio...

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

authors： O'Driscoll GA,Alpert NM,Matthysse SW,Levy DL,Rauch SL,Holzman PS

更新日期：1995-01-31 00:00:00

abstract：:The coding sequence for Anabaena 7120 glutamine synthetase [L-glutamate:ammonia ligase (ADP-forming), EC 6.3.1.1] are shown to be contained within a 7.5-kilobase-pair (kbp) HindIII fragment that has been cloned by plaque hybridization. The hybridization probe for the cyanobacterial gene was a recombinant plasmid conta...

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

authors： Fisher R,Tuli R,Haselkorn R

更新日期：1981-06-01 00:00:00

abstract：:Symbiotic microbes impact the severity of a variety of diseases through regulation of T-cell development. However, little is known regarding the molecular mechanisms by which this is accomplished. Here we report that a secreted factor, Erdr1, is regulated by the microbiota to control T-cell apoptosis. Erdr1 expression...

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

authors： Soto R,Petersen C,Novis CL,Kubinak JL,Bell R,Stephens WZ,Lane TE,Fujinami RS,Bosque A,O'Connell RM,Round JL

更新日期：2017-05-23 00:00:00

abstract：:Despite the widespread occurrence of spliceosomal introns in the genomes of higher eukaryotes, their origin remains controversial. One model proposes that the duplication of small genomic portions could have provided the boundaries for new introns. If this mechanism has occurred recently, the 5' and 3' boundaries of e...

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

authors： Zhuo D,Madden R,Elela SA,Chabot B

更新日期：2007-01-16 00:00:00

abstract：:In the mitochondrial genome of the hemichordate Balanoglossus carnosus, the codon AAA, which is assigned to lysine in most metazoans but to asparagine in echinoderms, is absent. Furthermore, the lysine tRNA gene carries an anticodon substitution that renders its gene product unable to decode AAA codons, whereas the as...

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

authors： Castresana J,Feldmaier-Fuchs G,Pääbo S

更新日期：1998-03-31 00:00:00

abstract：:While cells within tissues generate and sense 3D states of strain, the current understanding of the mechanics of fibrous extracellular matrices (ECMs) stems mainly from uniaxial, biaxial, and shear tests. Here, we demonstrate that the multiaxial deformations of fiber networks in 3D cannot be inferred solely based on t...

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

authors： Ban E,Wang H,Franklin JM,Liphardt JT,Janmey PA,Shenoy VB

更新日期：2019-04-02 00:00:00

abstract：:The human retinoic acid receptor (hRAR) is a member of the nuclear receptor superfamily that regulates the transcription of target genes in a ligand-dependent manner. The three hRAR isotypes are targets for retinoids that are used in the treatment of various diseases, including breast cancer and skin diseases. Drug ef...

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

authors： Klaholz BP,Mitschler A,Belema M,Zusi C,Moras D

更新日期：2000-06-06 00:00:00

abstract：:Engagement of high-affinity IgE receptors leads to activation of tyrosine and serine/threonine kinases and the immediate phosphorylation of receptor beta (serine and tyrosine) and gamma (threonine and tyrosine) chains. Receptor disengagement leads to dephosphorylation of beta and gamma chains via the action of undefin...

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

authors： Paolini R,Numerof R,Kinet JP

更新日期：1992-11-15 00:00:00

abstract：:Normal as well as Rous sarcoma virus-infected chicken pectoral and chicken embryo fibroblasts proliferate actively in a plasma containing medium of physiological ion concentrations (Ca2+, 1.2 mM; Mg2+, 0.7 mM). Reduction of medium calcium and magnesium concentrations is necessary to achieve selective quiescence of nor...

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

authors： Balk SD

更新日期：1980-11-01 00:00:00

abstract：:The cerebral cortex of mammals differentiates into functionally distinct areas that exhibit unique cytoarchitecture, connectivity, and molecular characteristics. Molecular specification of cells fated for limbic cortical areas, based on the expression of the limbic system-associated membrane protein (LAMP), occurs dur...

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

authors： Barbe MF,Levitt P

更新日期：1992-05-01 00:00:00

abstract：:Targeted ablation of the surfactant protein D (SP-D) gene caused chronic inflammation, emphysema, and fibrosis in the lungs of SP-D (-/-) mice. Although lung morphology was unperturbed during the first 2 weeks of life, airspace enlargement was observed by 3 weeks and progressed with advancing age. Inflammation consist...

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

authors： Wert SE,Yoshida M,LeVine AM,Ikegami M,Jones T,Ross GF,Fisher JH,Korfhagen TR,Whitsett JA

更新日期：2000-05-23 00:00:00

abstract：:Seven morphologically nontransformed (flat) revertants with reduced tumorigenicity in vivo have been isolated from populations of Kirsten sarcoma virus-transformed NIH 3T3 cells transfected with a cDNA expression library of normal human fibroblasts. Each revertant harbors 1-10 recombinant plasmids per cell and retains...

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

authors： Noda M,Kitayama H,Matsuzaki T,Sugimoto Y,Okayama H,Bassin RH,Ikawa Y

更新日期：1989-01-01 00:00:00

abstract：:The crystal structure of fructose-1,6-bisphosphatase (EC 3.1.3.11) complexed with fructose 6-phosphate, AMP, and Mg2+ has been solved by the molecular replacement method and refined at 2.5-A resolution to a R factor of 0.215, with root-mean-square deviations of 0.013 A and 3.5 degrees for bond lengths and bond angles,...

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

authors： Ke HM,Zhang YP,Lipscomb WN

更新日期：1990-07-01 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：:Although mathematical models and laboratory experiments have shown that species interactions can generate chaos, field evidence of chaos in natural ecosystems is rare. We report on a pristine rocky intertidal community located in one of the world's oldest marine reserves that has displayed a complex cyclic succession ...

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

authors： Benincà E,Ballantine B,Ellner SP,Huisman J

更新日期：2015-05-19 00:00:00

abstract：:As 3D culture has become central to investigation of tissue biology, mammary epithelial organoids have emerged as powerful tools for investigation of epithelial cell polarization and carcinogenesis. However, most current protocols start from single cells suspended in Matrigel, which can also restrict cell differentiat...

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

authors： Florian S,Iwamoto Y,Coughlin M,Weissleder R,Mitchison TJ

更新日期：2019-06-04 00:00:00

abstract：:Mouse tumor C1300 has been established in tissue culture. The cells have a round cell morphology in both the subcutaneous tumor and in suspension culture. However, when given a surface on which to attach, they send out processes up to 3 mm in length and assume the morphology of mature neurons. The attached cells are s...

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

authors： Schubert D,Humphreys S,Baroni C,Cohn M

更新日期：1969-09-01 00:00:00