spoT-dependent accumulation of guanosine tetraphosphate in response to fatty acid starvation in Escherichia coli.

abstract：:Telomerase is an RNA-directed DNA polymerase, composed of RNA and protein subunits, that replicates the telomere ends of linear eukaryotic chromosomes. Using a genetic strategy described here, we identify the product of the EST2 gene, Est2p, as a subunit of telomerase in the yeast Saccharomyces cerevisiae. Est2p is re...

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

authors： Counter CM,Meyerson M,Eaton EN,Weinberg RA

更新日期：1997-08-19 00:00:00

abstract：:Adaptive radiation is the evolution of ecological and phenotypic diversity within a rapidly multiplying lineage. Recent studies have identified general patterns in adaptive radiation and inferred that resource competition is a primary factor driving phenotypic divergence. The role and importance of other processes, su...

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

authors： Nosil P,Crespi BJ

更新日期：2006-06-13 00:00:00

abstract：:Complementary DNA (cDNA) specific for chick globin mRNA sequences fails to hybridize to total RNA extracted from chicken fibroblasts. After infection by Rous sarcoma virus, RNA complementary to globin cDNA is detectable in 100-500 copies per cell. Infection of fibroblasts with the transformation defective (td) deletio...

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

authors： Groudine M,Weintraub H

更新日期：1975-11-01 00:00:00

abstract：:From the types of ring chromosomes induced in x-irradiated Chinese hamster ovary (CHO) cells, we deduce the existence of switches in the polarity of chromosomal DNA; if there is a continuous DNA double helix along the full length of the chromosome then the polarity switches imply 3'-3' and 5'-5' phosphodiester linkage...

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

authors： Wolff S,Lindsley DL,Peacock WJ

更新日期：1976-03-01 00:00:00

abstract：:The activated human Ha-ras oncogene was subjected to the control of the promoter region of the murine whey acidic protein (Wap) gene, which is expressed in mammary epithelial cells in response to lactogenic hormones. The Wap-ras gene was stably introduced into the mouse germ line of five transgenic mice (one male and ...

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

authors： Andres AC,Schönenberger CA,Groner B,Hennighausen L,LeMeur M,Gerlinger P

更新日期：1987-03-01 00:00:00

abstract：:For the purpose of clarifying the magneto-orientation mechanism of several biological membrane systems, xylene-suspended thin-layered single crystals of lecithin, which is a major component of membranes, were subjected to magnetic fields of various strengths, and the orientation behavior of the crystals was analyzed. ...

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

authors： Sakurai I,Kawamura Y,Ikegami A,Iwayanagi S

更新日期：1980-12-01 00:00:00

abstract：:Accurate and timely surface precipitation measurements are crucial for water resources management, agriculture, weather prediction, climate research, as well as ground validation of satellite-based precipitation estimates. However, the majority of the land surface of the earth lacks such data, and in many parts of the...

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

authors： Overeem A,Leijnse H,Uijlenhoet R

更新日期：2013-02-19 00:00:00

abstract：:The N-methyl-D-aspartate (NMDA) receptor, a subtype of excitatory amino acid receptor, mediates synaptic responses in many regions of the central nervous system. This receptor plays a critical role in the mechanisms of both synaptic plasticity and excitotoxicity. Although these receptors were generally thought to be a...

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

authors： Monaghan DT,Olverman HJ,Nguyen L,Watkins JC,Cotman CW

更新日期：1988-12-01 00:00:00

abstract：:Experiments were designed with the aim of understanding the mechanism whereby the lambda repressor inhibits messenger RNA synthesis. Complexes containing lambda DNA and RNA polymerase were isolated from repressed and derepressed lysogens and analyzed for the relative amounts of RNA polymerase per phage genome. The dat...

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

authors： Hayward WS,Green MH

更新日期：1969-11-01 00:00:00

abstract：:With continued debate over the functional significance of adult neurogenesis, identifying an in vivo correlate of neurogenesis has become an important goal. Here we rely on the coupling between neurogenesis and angiogenesis and test whether MRI measurements of cerebral blood volume (CBV) provide an imaging correlate o...

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

authors： Pereira AC,Huddleston DE,Brickman AM,Sosunov AA,Hen R,McKhann GM,Sloan R,Gage FH,Brown TR,Small SA

更新日期：2007-03-27 00:00:00

abstract：:The female germ cell stage of primary importance in radiation genetic hazards is the immature, arrested oocyte. In the mouse, this stage has a near zero or zero sensitivity to mutation induction by radiation. However, the application of these mouse results to women has been questioned on the ground that the mouse arre...

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

authors： Russell WL

更新日期：1977-08-01 00:00:00

abstract：:Fertilization and certain later stages in mammalian embryonic development require fusion between membranes of individual cells. The mechanism of eukaryotic cell-cell fusion is unknown, and no surface molecules required for this process have been unequivocally identified. The role of the sperm surface protein fertilin ...

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

authors： Myles DG,Kimmel LH,Blobel CP,White JM,Primakoff P

更新日期：1994-05-10 00:00:00

abstract：:It is widely accepted that the heavily glycosylated glycoprotein gp120 on the surface of HIV-1 shields peptide epitopes from recognition by the immune system and may promote infection in vivo by interaction with dendritic cells and transport to tissue rich in CD4(+) T cells such as lymph nodes. A conserved cluster of ...

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

authors： Wang SK,Liang PH,Astronomo RD,Hsu TL,Hsieh SL,Burton DR,Wong CH

更新日期：2008-03-11 00:00:00

abstract：:We measured the superconducting transition temperature of (6)Li between 16 and 26 GPa, and report the lightest system to exhibit superconductivity to date. The superconducting phase diagram of (6)Li is compared with that of (7)Li through simultaneous measurement in a diamond anvil cell (DAC). Below 21 GPa, Li exhibits...

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

authors： Schaeffer AM,Temple SR,Bishop JK,Deemyad S

更新日期：2015-01-06 00:00:00

abstract：:Three enzyme reactions have been reported to catalyze the synthesis of phosphoribosylamine in eukaryotic cells. These activities are glutamine phosphoribosylpyrophosphate (P-Rib-P-P) amidotransferase [amidophosphoribosyl-transferase; 5-phosphoribosylamine: pyrophosphate phosphoribosyltransferase (glutamate-amidating) ...

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

authors： Holmes EW,King GL,Leyva A,Singer SC

更新日期：1976-07-01 00:00:00

abstract：:Multiple studies have established that microRNAs (miRNAs) are involved in the initiation and progression of cancer. Notably, miR-155 is one of the most overexpressed miRNAs in several solid and hematological malignancies. Ectopic miR-155 expression in mice B cells (Eμ-miR-155 transgenic mice) has been shown to induce ...

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

authors： Sandhu SK,Volinia S,Costinean S,Galasso M,Neinast R,Santhanam R,Parthun MR,Perrotti D,Marcucci G,Garzon R,Croce CM

更新日期：2012-12-04 00:00:00

abstract：:The amounts of mRNAs encoding alpha 1, alpha 6, beta 2, beta 3, gamma 2, and delta subunits of gamma-aminobutyrate type A (GABAA) receptors and the gold immunolabeling density of their translation products were monitored during the growth of neonatal rat granule cells in primary culture. We investigated possible corre...

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

authors： Zheng TM,Zhu WJ,Puia G,Vicini S,Grayson DR,Costa E,Caruncho HJ

更新日期：1994-11-08 00:00:00

abstract：:Meningococcal meningitis remains a substantial cause of mortality and morbidity worldwide. Until recently, countries in the African meningitis belt were susceptible to devastating outbreaks, largely attributed to serogroup A Neisseria meningitidis (MenA). Vaccination with glycoconjugates of MenA capsular polysaccharid...

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

authors： Henriques P,Dello Iacono L,Gimeno A,Biolchi A,Romano MR,Arda A,Bernardes GJL,Jimenez-Barbero J,Berti F,Rappuoli R,Adamo R

更新日期：2020-11-24 00:00:00

abstract：:In an investigation to determine how proteins are localized within the nucleus of a cell, we demonstrate that the restriction endonuclease EcoRI is able to enter and function within the nucleus of Saccharomyces cerevisiae when this prokaryotic protein is synthesized in vivo. The EcoRI endonuclease was produced in yeas...

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

authors： Barnes G,Rine J

更新日期：1985-03-01 00:00:00

abstract：:Inherited deficiencies of the enzymes adenosine deaminase (adenosine aminohydrolase; EC 3.5.4.4) and purine nucleoside phosphorylase (purine-nucleoside:orthophosphate ribosyltransferase; EC 2.4.2.1) preferentially interfere with lymphocyte development while sparing most other organ systems. Previous experiments have s...

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

authors： Carson DA,Kaye J,Seegmiller JE

更新日期：1977-12-01 00:00:00

abstract：:Effects of temperature on biological processes are complex. Diffusion is less affected than the diverse enzymatic reactions that have distinct individual temperature profiles. Hence thermal fluctuations pose a formidable challenge to ectothermic organisms in which body temperature is largely dictated by the ambient te...

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

authors： Radermacher PT,Myachina F,Bosshardt F,Pandey R,Mariappa D,Müller HA,Lehner CF

更新日期：2014-04-15 00:00:00

abstract：:The 4D organization of the interphase nucleus, or the 4D Nucleome (4DN), reflects a dynamical interaction between 3D genome structure and function and its relationship to phenotype. We present initial analyses of the human 4DN, capturing genome-wide structure using chromosome conformation capture and 3D imaging, and f...

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

authors： Chen H,Chen J,Muir LA,Ronquist S,Meixner W,Ljungman M,Ried T,Smale S,Rajapakse I

更新日期：2015-06-30 00:00:00

abstract：:We previously demonstrated that the primary region of factor IX and IXa responsible for saturable specific binding to bovine aortic endothelial cells resides in residues 3-11 at the amino terminus of factor IX. We also demonstrated that mutations of lysine to alanine at residue 5, factor IX K5A, or valine to lysine at...

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

authors： Cheung WF,van den Born J,Kühn K,Kjellén L,Hudson BG,Stafford DW

更新日期：1996-10-01 00:00:00

abstract：:Nonsyndromic clefting of the lip and palate in humans has a highly complex etiology, with both multiple genetic loci and exposure to teratogens influencing susceptibility. Previous studies using mouse models have examined only very small portions of the genome. Here we report the findings of a genome-wide search for s...

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

authors： Diehl SR,Erickson RP

更新日期：1997-05-13 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：:Donor DNA molecules carrying Tn1 or Tn3 deletion mutants do not need to replicate in order to participate in replicon fusion recombination events during which the Tn1/Tn3 element is duplicated. We have assayed Tn1 delta Ap-mediated replicon fusion events involving plasmid R388 and the bacteriophage lambda-derived plas...

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

authors： Muster CJ,Shapiro JA,MacHattie LA

更新日期：1983-04-01 00:00:00

abstract：:Operating rooms (ORs) are inhabited by hierarchical, mixed-gender clinical teams that are often prone to conflict. In evolutionary terms, one expects more within- than between-gender rivalries, especially since the OR is a place where all sorts of social interactions occur, not merely technical communications. To docu...

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

authors： Jones LK,Jennings BM,Higgins MK,de Waal FBM

更新日期：2018-07-17 00:00:00

abstract：:Macrophages use phagocytosis to control the spread of pathogens in the body, to clear apoptotic cells, and to aid in tissue remodeling. The phagosomal membrane is traditionally thought to originate from the plasmalemma and then go through a series of maturation steps involving sequential fusion with endosomal compartm...

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

authors： Rogers LD,Foster LJ

更新日期：2007-11-20 00:00:00

abstract：:Human embryonic stem cells have the potential to differentiate into various cell types and, thus, may be useful as a source of cells for transplantation or tissue engineering. We describe here the differentiation steps of human embryonic stem cells into endothelial cells forming vascular-like structures. The human emb...

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

authors： Levenberg S,Golub JS,Amit M,Itskovitz-Eldor J,Langer R

更新日期：2002-04-02 00:00:00

abstract：:We are interested in using recombinant adeno-associated viral vectors in the treatment of hemophilia A. Because of the size constraints of recombinant adeno-associated viral vectors, we delivered the heavy and light chains of the human factor 8 (hFVIII) cDNA independently by using two separate vectors. Recombinant AAV...

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

authors： Burton M,Nakai H,Colosi P,Cunningham J,Mitchell R,Couto L

更新日期：1999-10-26 00:00:00