Murine leukemia virus morphogenesis: cleavage of P70 in vitro can be accompanied by a shift from a concentrically coiled internal strand ("immature") to a collapsed ("mature") form of the virus core.

abstract：:Scientific and engineering innovation is vital for American competitiveness, quality of life, and national security. However, too few American students, especially women, pursue these fields. Although this problem has attracted enormous attention, rigorously tested interventions outside artificial laboratory settings ...

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

authors： Dennehy TC,Dasgupta N

更新日期：2017-06-06 00:00:00

abstract：:The DnaE intein in Synechocystis sp. strain PCC6803 is the first and only naturally split intein that has been identified so far. It is capable of catalyzing a protein trans-splicing mechanism to assemble a mature protein from two separate precursors. Therefore, it is a powerful tool for protein modification and engin...

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

authors： Yang J,Fox GC Jr,Henry-Smith TV

更新日期：2003-03-18 00:00:00

abstract：:Lineage plasticity is a prominent feature of pancreatic ductal adenocarcinoma (PDA) cells, which can occur via deregulation of lineage-specifying transcription factors. Here, we show that the zinc finger protein ZBED2 is aberrantly expressed in PDA and alters tumor cell identity in this disease. Unexpectedly, our epig...

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

authors： Somerville TDD,Xu Y,Wu XS,Maia-Silva D,Hur SK,de Almeida LMN,Preall JB,Koo PK,Vakoc CR

更新日期：2020-05-26 00:00:00

abstract：:Despite the importance of mitotic cell rounding in tissue development and cell proliferation, there remains a paucity of approaches to investigate the mechanical robustness of cell rounding. Here we introduce ion beam-sculpted microcantilevers that enable precise force-feedback-controlled confinement of single cells w...

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

authors： Cattin CJ,Düggelin M,Martinez-Martin D,Gerber C,Müller DJ,Stewart MP

更新日期：2015-09-08 00:00:00

abstract：:Lipoproteins are emulsion particles that consist of lipids and apolipoproteins. Their natural function is to transport lipids and/or cholesterol to different tissues. We have taken advantage of the hydrophobic interior of these natural emulsions to solubilize DNA. Negatively charged DNA was first complexed with cation...

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

authors： Hara T,Tan Y,Huang L

更新日期：1997-12-23 00:00:00

abstract：:Genomes exhibit diverse patterns of species-specific GC content, GC and AT skews, codon bias, and mutation bias. Despite intensive investigations and the rapid accumulation of sequence data, the causes of these a priori different genome biases have not been agreed on and seem multifactorial and idiosyncratic. We show ...

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

authors： Vetsigian K,Goldenfeld N

更新日期：2009-01-06 00:00:00

abstract：:Recent scholarship suggests that the genomes of those around us affect our own phenotypes. Much of the empirical evidence for such "metagenomic" effects comes from animal studies, where the socio-genetic environment can be easily manipulated. Among humans, it is more difficult to identify such effects given the nonran...

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

authors： Sotoudeh R,Harris KM,Conley D

更新日期：2019-08-13 00:00:00

abstract：:A number of recent studies have shown that iron dissolution in Fe-containing dust aerosol can be linked to source material (mineral or anthropogenic), mineralogy, and iron speciation. All of these factors need to be incorporated into atmospheric chemistry models if these models are to accurately predict the impact of ...

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

authors： Rubasinghege G,Lentz RW,Scherer MM,Grassian VH

更新日期：2010-04-13 00:00:00

abstract：:Memory stretches over a lifetime. In controlled laboratory settings, the hippocampus and other medial temporal lobe brain structures have been shown to represent space and time on the scale of meters and seconds. It remains unclear whether the hippocampus also represents space and time over the longer scales necessary...

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

authors： Nielson DM,Smith TA,Sreekumar V,Dennis S,Sederberg PB

更新日期：2015-09-01 00:00:00

abstract：:An assay has been developed to test the hypothesis that neurons from a limited area of the retina will adhere preferentially to that part of the optic tectum near their normal synaptic termini. The method measures the adherence of (32)P-labeled cell bodies from either the dorsal or ventral half of the neural retina of...

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

authors： Barbera AJ,Marchase RB,Roth S

更新日期：1973-09-01 00:00:00

abstract：:Invasive organisms pose a global threat and are exceptionally difficult to eradicate after they become abundant in their new habitats. We report a successful multitactic strategy for combating the pink bollworm (Pectinophora gossypiella), one of the world's most invasive pests. A coordinated program in the southwester...

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

authors： Tabashnik BE,Liesner LR,Ellsworth PC,Unnithan GC,Fabrick JA,Naranjo SE,Li X,Dennehy TJ,Antilla L,Staten RT,Carrière Y

更新日期：2021-01-05 00:00:00

abstract：:The primitive neurohypophyseal nonapeptide oxytocin (OXT) has established functions in parturition, lactation, appetite, and social behavior. We have shown that OXT has direct actions on the mammalian skeleton, stimulating bone formation by osteoblasts and modulating the genesis and function of bone-resorbing osteocla...

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

authors： Sun L,Lizneva D,Ji Y,Colaianni G,Hadelia E,Gumerova A,Ievleva K,Kuo TC,Korkmaz F,Ryu V,Rahimova A,Gera S,Taneja C,Khan A,Ahmad N,Tamma R,Bian Z,Zallone A,Kim SM,New MI,Iqbal J,Yuen T,Zaidi M

更新日期：2019-12-16 00:00:00

abstract：:Murine mammary tumor virus (MMTV) expression is analyzed in a T-lymphoid cell line (T1M1) sensitive to the killing effect of glucocorticoids and in two of its variants, one resistant (T1M1r) and one supersensitive (T1M1ss) to glucocorticoid-induced lymphocytolysis. In the T1M1 line, MMTV is expressed and induced appro...

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

authors： Mermod JJ,Bourgeois S,Defer N,Crépin M

更新日期：1983-01-01 00:00:00

abstract：:The positions of transition states along reaction coordinates (r++) for simple chemical reactions are often estimated from Leffler alpha values, the slope of plots of DeltaG++ (activation energy) versus DeltaG(0) (equilibrium free energy) for a series of structural variants. Protein folding is more complex than simple...

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

authors： Fersht AR

更新日期：2004-10-05 00:00:00

abstract：:By examining many alternative arrangements of cortical areas, we have found that the arrangement actually present in the brain minimizes the volume of the axons required for interconnecting the areas. Our observations support the notion that the organization of cortical areas has evolved to optimize interareal connect...

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

authors： Klyachko VA,Stevens CF

更新日期：2003-06-24 00:00:00

abstract：:The testis-determining gene Sry is located on the short arm of the mouse Y chromosome in a region known to have undergone duplications and rearrangements in comparison with the equivalent portion of the human Y chromosome. Detailed analysis of the Sry genomic locus reveals a further difference in that the mouse Sry op...

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

authors： Gubbay J,Vivian N,Economou A,Jackson D,Goodfellow P,Lovell-Badge R

更新日期：1992-09-01 00:00:00

abstract：:Adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] activity of purified secretory vesicle membranes from the adrenal medulla is inhibited by I-isoproterenol and I-epinephrine, as well as by nerve growth factor (NGF). The effect of these agents was found to be dose-dependent and, in the case of the cat...

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

authors： Nikodijevic O,Nikodijevic B,Zinder O,Yu MY,Guroff G,Pollard HB

更新日期：1976-03-01 00:00:00

abstract：:The preferential inactivation of the paternal X chromosome in extraembryonic cells during early mouse development is an example of parental imprinting, but it has not been studied at the transcriptional level because standard methods of measuring RNA levels do not allow detection of allele-specific RNAs in individual ...

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

authors： Singer-Sam J,Chapman V,LeBon JM,Riggs AD

更新日期：1992-11-01 00:00:00

abstract：:Dimyristoyl lecithin liposomes, containing cytochrome b5 reductase (NADH:ferricytochrome b5 oxidoreductase, EC 1.6.2.2) and varying amounts of cytochrome b5, were used to measure flavoprotein catalysis alone and catalysis requiring electron transfer between the reductase and cytochrome as a function of temperature. Wh...

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

authors： Strittmatter P,Rogers MJ

更新日期：1975-07-01 00:00:00

abstract：:During CsCl isopycnic centrifugation at 20 mM Mg(++), Escherichia coli 30S ribosomal subunits specifically lose proteins S1, S2, S3, S5, S9, S10, and S14. The resultant 30S core is unable to stimulate the GTPase activity of EF-G in the presence of 50S subunits. Activity could be restored to a small extent by adding ba...

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

authors： Marsh RC,Parmeggiani A

更新日期：1973-01-01 00:00:00

abstract：:Tomato plants overexpressing a prosystemin gene that encodes the precursor of a mobile wound signal called systemin have been shown previously to constitutively synthesize extraordinarily high levels of two defensive proteinase inhibitor proteins in leaves in the absence of wounding. We herein report that leaves of th...

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

authors： Constabel CP,Bergey DR,Ryan CA

更新日期：1995-01-17 00:00:00

abstract：:When yeast from the early stages of meiosis are transferred from sporulation to growth medium, they can reenter the mitotic cell cycle directly. In contrast, cells from later stages of meiosis (after the initiation of the first nuclear division) will complete meiosis and sporulation despite the shift to growth medium,...

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

authors： Honigberg SM,Esposito RE

更新日期：1994-07-05 00:00:00

abstract：:How did language evolve? A popular approach points to the similarities between the ontogeny and phylogeny of language. Young children's language and nonhuman primates' signing both appear formulaic with limited syntactic combinations, thereby suggesting a degree of continuity in their cognitive abilities. To evaluate ...

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

authors： Yang C

更新日期：2013-04-16 00:00:00

abstract：:Particular major histocompatibility complex (MHC) class II alleles clearly contribute to T cell-mediated autoimmune type 1 diabetes (T1D) in both humans and nonobese diabetic (NOD) mice. However, studies in NOD mice indicate MHC class I-restricted T cell responses are also essential to T1D development. In humans, epid...

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

authors： Marron MP,Graser RT,Chapman HD,Serreze DV

更新日期：2002-10-15 00:00:00

abstract：:The alternative adaptive immune system of jawless vertebrates is based on different isotypes of variable lymphocyte receptors (VLRs) that are composed of leucine-rich repeats (LRRs) and expressed by distinct B- and T-like lymphocyte lineages. VLRB is expressed by B-like cells, whereas VLRA and VLRC are expressed by tw...

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

authors： Holland SJ,Gao M,Hirano M,Iyer LM,Luo M,Schorpp M,Cooper MD,Aravind L,Mariuzza RA,Boehm T

更新日期：2014-10-14 00:00:00

abstract：:In many naturally occurring habitats, bacteria live in micrometer-size confined spaces. Although bacterial growth and motility in such constrictions is of great interest to fields as varied as soil microbiology, water purification, and biomedical research, quantitative studies of the effects of confinement on bacteria...

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

authors： Männik J,Driessen R,Galajda P,Keymer JE,Dekker C

更新日期：2009-09-01 00:00:00

abstract：:Genome packaging is an essential step in virus replication and a potential drug target. Single-stranded RNA viruses have been thought to encapsidate their genomes by gradual co-assembly with capsid subunits. In contrast, using a single molecule fluorescence assay to monitor RNA conformation and virus assembly in real ...

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

authors： Borodavka A,Tuma R,Stockley PG

更新日期：2012-09-25 00:00:00

abstract：:We compared students' self-reported perception of learning with their actual learning under controlled conditions in large-enrollment introductory college physics courses taught using 1) active instruction (following best practices in the discipline) and 2) passive instruction (lectures by experienced and highly rated...

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

authors： Deslauriers L,McCarty LS,Miller K,Callaghan K,Kestin G

更新日期：2019-09-24 00:00:00

abstract：:We have isolated three classes of monoclonal antibodies against Drosophila cell-surface antigens that are expressed with positional specificity in imaginal discs. Comparison of immunofluorescence patterns with the wing-disc fate map reveals that expression of the antigens is not directly related to the specific type o...

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

authors： Brower DL,Wilcox M,Piovant M,Smith RJ,Reger LA

更新日期：1984-12-01 00:00:00

abstract：:Quinate:NAD(+) 3-oxidoreductase (EC 1.1.1.24) from carrot cell suspension cultures has previously been shown to be activated by phosphorylation and inactivated by dephosphorylation. Here it is shown that the reactivation of the inactivated quinate:NAD(+) oxidoreductase is an enzyme-mediated process that requires ATP a...

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

authors： Ranjeva R,Refeno G,Boudet AM,Marmé D

更新日期：1983-09-01 00:00:00