Ancient helium and tungsten isotopic signatures preserved in mantle domains least modified by crustal recycling.

abstract：:Theories of density-dependent natural selection predict that evolution should favor those genotypes with the highest per capita rates of population growth under the current density conditions. These theories are silent about the mechanisms that may give rise to these increases in density-dependent growth rates. We hav...

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

authors： Guo PZ,Mueller LD,Ayala FJ

更新日期：1991-12-01 00:00:00

abstract：:Kelp forests (Order Laminariales) form key biogenic habitats in coastal regions of temperate and Arctic seas worldwide, providing ecosystem services valued in the range of billions of dollars annually. Although local evidence suggests that kelp forests are increasingly threatened by a variety of stressors, no comprehe...

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

authors： Krumhansl KA,Okamoto DK,Rassweiler A,Novak M,Bolton JJ,Cavanaugh KC,Connell SD,Johnson CR,Konar B,Ling SD,Micheli F,Norderhaug KM,Pérez-Matus A,Sousa-Pinto I,Reed DC,Salomon AK,Shears NT,Wernberg T,Anderson RJ,Barre

更新日期：2016-11-29 00:00:00

abstract：:We determined the crystal structure of the Escherichia coli nucleoid-associated HUalphabeta protein by x-ray diffraction and observed that the heterodimers form multimers with octameric units in three potential arrangements, which may serve specialized roles in different DNA transaction reactions. It is of special imp...

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

authors： Guo F,Adhya S

更新日期：2007-03-13 00:00:00

abstract：:Amputation of the zebrafish caudal fin stimulates regeneration of the dermal skeleton and reexpression of sonic hedgehog (shh)-signaling pathway genes. Expression patterns suggest a role for shh signaling in the secretion and patterning of the regenerating dermal bone, but a direct role has not been demonstrated. We e...

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

authors： Quint E,Smith A,Avaron F,Laforest L,Miles J,Gaffield W,Akimenko MA

更新日期：2002-06-25 00:00:00

abstract：:Cytochrome c oxidase (COX) is a 13-subunit protein complex that catalyzes the last step in mitochondrial electron transfer in mammals. Of the 10 subunits encoded by nuclear DNA (three are mtDNA products), some are expressed as tissue- and/or development-specific isoforms. For COX subunit VIII, previous work showed tha...

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

authors： Goldberg A,Wildman DE,Schmidt TR,Huttemann M,Goodman M,Weiss ML,Grossman LI

更新日期：2003-05-13 00:00:00

abstract：:A way to assess specific CD8+ T-cell activity in a skin test analogous to the conventional delayed-type hypersensitivity (DTH) reaction for CD4+ T cells is presented. Local injection of viral class I binding peptides caused a specific CD8+ T-cell-mediated DTH in footpads of virally infected mice. The DTH was inducible...

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

authors： Kündig TM,Althage A,Hengartner H,Zinkernagel RM

更新日期：1992-08-15 00:00:00

abstract：:A defect in the yeast GEF1 gene, a CLC chloride channel homolog leads to an iron requirement and cation sensitivity. The iron requirement is due to a failure to load Cu2+ onto a component of the iron uptake system, Fet3. This process, which requires both Gef1 and the Menkes disease Cu2+-ATPase yeast homolog Ccc2, occu...

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

authors： Gaxiola RA,Yuan DS,Klausner RD,Fink GR

更新日期：1998-03-31 00:00:00

abstract：:Pseudoxanthoma elasticum (PXE) is an autosomal recessive disease characterized by progressive ectopic mineralization of the skin, eyes, and arteries, for which no effective treatment exists. PXE is caused by inactivating mutations in the gene encoding ATP-binding cassette sub-family C member 6 (ABCC6), an ATP-dependen...

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

authors： Jansen RS,Küçükosmanoglu A,de Haas M,Sapthu S,Otero JA,Hegman IE,Bergen AA,Gorgels TG,Borst P,van de Wetering K

更新日期：2013-12-10 00:00:00

abstract：:The promoter of the bean PAL2 gene (encoding phenylalanine ammonia-lyase; EC 4.3.1.5) is a model for studies of tissue-restricted gene expression in plants. Petal epidermis is one of the tissues in which this promoter is activated in tobacco. Previous work suggested that a major factor establishing the pattern of PAL2...

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

authors： Sablowski RW,Baulcombe DC,Bevan M

更新日期：1995-07-18 00:00:00

abstract：:A common challenge in pathogen discovery by deep sequencing approaches is to recognize viral or subviral pathogens in samples of diseased tissue that share no significant homology with a known pathogen. Here we report a homology-independent approach for discovering viroids, a distinct class of free circular RNA subvir...

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

authors： Wu Q,Wang Y,Cao M,Pantaleo V,Burgyan J,Li WX,Ding SW

更新日期：2012-03-06 00:00:00

abstract：:The bacterio-opsin gene was introduced into a "blind" Halobacterium salinarium mutant that (i) lacked all the four retinal proteins [bacteriorhodopsin (BR), halorhodopsin, and sensory rhodopsins (SRs) I and II] and the transducer protein for SRI and (ii) showed neither attractant response to long wavelength light nor ...

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

authors： Bibikov SI,Grishanin RN,Kaulen AD,Marwan W,Oesterhelt D,Skulachev VP

更新日期：1993-10-15 00:00:00

abstract：:Natural killer (NK) cells form three functionally distinct populations of effectors: competent cytolytic effectors able to bind and kill target cells and two subsets of nonlytic effectors, one able and the other unable to bind target cells. A flow cytometric method was developed, based on size and two-color fluorescen...

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

authors： Lebow LT,Bonavida B

更新日期：1990-08-01 00:00:00

abstract：:We developed a helper-dependent adenoviral vector for cystic fibrosis lung gene therapy. The vector expresses cystic fibrosis transmembrane conductance regulator (Cftr) using control elements from cytokeratin 18. The vector expressed properly localized CFTR in cultured cells and in the airway epithelia of mice. Cftr R...

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

authors： Koehler DR,Sajjan U,Chow YH,Martin B,Kent G,Tanswell AK,McKerlie C,Forstner JF,Hu J

更新日期：2003-12-23 00:00:00

abstract：:The binding of 125I-labeled wheat germ agglutinin (WGA) to parental and three distinct WGA-resistant Chinese hamster ovary cell lines possessing modified cell surface carbohydrate structures has been examined over a 10(6)-fold range of WGA concentrations. The Scatchard plot for WGA binding to parental cells was comple...

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

authors： Stanley P,Carver JP

更新日期：1977-11-01 00:00:00

abstract：:The protein-protein interaction (PPI) network is crucial for cellular information processing and decision-making. With suitable inputs, PPI networks drive the cells to diverse functional outcomes such as cell proliferation or cell death. Here, we characterize the structural controllability of a large directed human PP...

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

authors： Vinayagam A,Gibson TE,Lee HJ,Yilmazel B,Roesel C,Hu Y,Kwon Y,Sharma A,Liu YY,Perrimon N,Barabási AL

更新日期：2016-05-03 00:00:00

abstract：:The mid-winter development of refractoriness to melatonin (Mel) triggers recrudescence of the atrophied reproductive apparatus of rodents. As a consequence, over-wintering animals become reproductively competent just before the onset of spring conditions favorable for breeding. The neural target tissues that cease to ...

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

authors： Freeman DA,Zucker I

更新日期：2001-05-22 00:00:00

abstract：:The human gut is home to trillions of microbes, thousands of bacterial phylotypes, as well as hydrogen-consuming methanogenic archaea. Studies in gnotobiotic mice indicate that Methanobrevibacter smithii, the dominant archaeon in the human gut ecosystem, affects the specificity and efficiency of bacterial digestion of...

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

authors： Samuel BS,Hansen EE,Manchester JK,Coutinho PM,Henrissat B,Fulton R,Latreille P,Kim K,Wilson RK,Gordon JI

更新日期：2007-06-19 00:00:00

abstract：:The inositol 1,4,5-trisphosphate receptor (IP3R) in the endoplasmic reticulum mediates calcium signaling that impinges on intracellular processes. IP3Rs are allosteric proteins comprising four subunits that form an ion channel activated by binding of IP3 at a distance. Defective allostery in IP3R is considered crucial...

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

authors： Hamada K,Terauchi A,Nakamura K,Higo T,Nukina N,Matsumoto N,Hisatsune C,Nakamura T,Mikoshiba K

更新日期：2014-09-23 00:00:00

abstract：:Low-barrier hydrogen bonds (LBHBs) have been proposed to play roles in protein functions, including enzymatic catalysis and proton transfer. Transient formation of LBHBs is expected to stabilize specific reaction intermediates. However, based on experimental results and theoretical considerations, arguments against th...

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

authors： Yamaguchi S,Kamikubo H,Kurihara K,Kuroki R,Niimura N,Shimizu N,Yamazaki Y,Kataoka M

更新日期：2009-01-13 00:00:00

abstract：:Asexual freshwater planarians reproduce by tearing themselves into two pieces by a process called binary fission. The resulting head and tail pieces regenerate within about a week, forming two new worms. Understanding this process of ripping oneself into two parts poses a challenging biomechanical problem. Because pla...

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

authors： Malinowski PT,Cochet-Escartin O,Kaj KJ,Ronan E,Groisman A,Diamond PH,Collins ES

更新日期：2017-10-10 00:00:00

abstract：:The Hawaiian Islands are renowned for some of the most spectacular species radiations in the world. Most of these radiations have been attributed to single colonization events, although the evidence supporting monophyletic origins is often poorly resolved and/or ambiguous. Without a concrete understanding of the origi...

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

authors： Gillespie RG,Croom HB,Palumbi SR

更新日期：1994-03-15 00:00:00

abstract：:Protein kinases are important mediators of much of the signal transduction that occurs in eukaryotic cells. Unfortunately, the identification of protein kinase substrates has proven to be a difficult task, and we generally know few, if any, of the physiologically relevant targets of any particular kinase. Here, we des...

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

authors： Budovskaya YV,Stephan JS,Deminoff SJ,Herman PK

更新日期：2005-09-27 00:00:00

abstract：:We developed a microfluidics-based model to quantify cell-level processes modulating the pathophysiology of sickle cell disease (SCD). This in vitro model enabled quantitative investigations of the kinetics of cell sickling, unsickling, and cell rheology. We created short-term and long-term hypoxic conditions to simul...

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

authors： Du E,Diez-Silva M,Kato GJ,Dao M,Suresh S

更新日期：2015-02-03 00:00:00

abstract：:The hydrodynamic properties of the detergent-solubilized, terminal membrane complex of serum complement components C5-C9 [C5b-9(m)] were studied to obtain an estimate of its molecular weight. In a solution of Triton X-100/deoxycholate, the protein complex binds 17% Triton X-100 and 11% deoxycholate by weight. The sedi...

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

authors： Bhakdi S,Tranum-Jensen J

更新日期：1981-03-01 00:00:00

abstract：:The recently evolved Hawaiian species Drosophila silvestris has a subdivided population structure and shows great spatial heterogeneity in chromosome inversion distributions and frequencies within its extremely limited geographic range. Pattern analysis of the 11 chromosomal polymorphisms in the context of the recentl...

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

authors： Craddock EM,Carson HL

更新日期：1989-06-01 00:00:00

abstract：:Melanocyte stimulating hormone coupled to Sepharose effects an increase in tryosinase (EC 1.14.18.1; monophenol monoxygenase) activity of cultivated mouse melanoma cells. Synchronized cells are found to respond to melanocyte stimulating hormone only in the G2 phase of the cell cycle, although their response to cyclic ...

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

authors： Varga JM,Dipasquale A,Pawelek J,McGuire JS,Lerner AB

更新日期：1974-05-01 00:00:00

abstract：:The chemotherapeutic drug Taxol is known to interact within a specific site on beta-tubulin. Although the general location of the site has been defined by photoaffinity labeling and electron crystallography, the original data were insufficient to make an absolute determination of the bound conformation. We have now co...

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

authors： Snyder JP,Nettles JH,Cornett B,Downing KH,Nogales E

更新日期：2001-04-24 00:00:00

abstract：:Using a comprehensive transcriptome analysis, a Z chromosome-linked chicken homolog of hemogen (cHEMGN) was identified and shown to be specifically involved in testis differentiation in early chicken embryos. Hemogen [Hemgn in mice, EDAG (erythroid differentiation-associated gene protein) in humans] was recently chara...

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

authors： Nakata T,Ishiguro M,Aduma N,Izumi H,Kuroiwa A

更新日期：2013-02-26 00:00:00

abstract：:Pronounced bright and dark bands are seen at the bright and dark edges of half-shadows and similar distributions of illumination. These are the so-called Mach bands. A pair of vertical Mach bands was generated with a ramp pattern in the central strip of a horizontal tripartite oscilloscope display. This pattern consis...

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

authors： Ratliff F,Milkman N,Rennert N

更新日期：1983-07-01 00:00:00

abstract：:Transcriptionally silent genes are maintained in inaccessible chromatin. Accessibility of these genes requires their modification by chromatin remodeling complexes (CRCs), which are recruited to promoters by sequence-specific DNA-binding proteins. Early B-cell factor (EBF), which is crucial for B-cell lineage specific...

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

authors： Gao H,Lukin K,Ramírez J,Fields S,Lopez D,Hagman J

更新日期：2009-07-07 00:00:00