Reversion of recombinant toxoids: mutations in diphtheria toxin that partially compensate for active-site deletions.

abstract：:Despite their relative simplicity, bacteria have complex anatomy at the subcellular level. At the cell poles of Caulobacter crescentus, a 177-amino acid (aa) protein called PopZ self-assembles into 3D polymeric superstructures. Remarkably, we find that this assemblage interacts directly with at least eight different p...

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

authors： Holmes JA,Follett SE,Wang H,Meadows CP,Varga K,Bowman GR

更新日期：2016-11-01 00:00:00

abstract：:All cells are unavoidably exposed to chemicals that can alkylate DNA to form genotoxic damage. Among the various DNA lesions formed, O(6)-alkylguanine lesions can be highly cytotoxic, and we recently demonstrated that O(6)-methylguanine (O(6)MeG) and O(6)-chloroethylguanine (O(6)CEG) specifically initiate apoptosis in...

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

authors： Hickman MJ,Samson LD

更新日期：1999-09-14 00:00:00

abstract：:R. A. Fisher's 1930 "reproductive value" is defined as the contribution made by a population's initial age elements to its asymptotically dominating exponential growth mode. For the Leslie discrete-time model, it is the characteristic row vector of the Leslie matrix, and for the integral-equation model of Lotka the si...

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

authors： Samuelson PA

更新日期：1977-11-01 00:00:00

abstract：:Blue mold of tobacco is caused by the fungus Peronospora tabacina. Its spores are released in the morning when the relative humidity falls, but they require free water for germination. Traditionally, the walls of the shade tents are raised to control the pathogen by drying leaves. We show that raising the walls does n...

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

authors： Aylor DE,Taylor GS

更新日期：1982-01-01 00:00:00

abstract：:Discovering the visual features and representations used by the brain to recognize objects is a central problem in the study of vision. Recently, neural network models of visual object recognition, including biological and deep network models, have shown remarkable progress and have begun to rival human performance in...

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

authors： Ullman S,Assif L,Fetaya E,Harari D

更新日期：2016-03-08 00:00:00

abstract：:Thymopoietin, a polypeptide hormone of the thymus that has pleiotropic actions on the immune, endocrine, and nervous systems, potently interacts with the neuromuscular nicotinic acetylcholine receptor. Thymopoietin binds to the nicotinic alpha-bungarotoxin (alpha-BGT) receptor in muscle and, like alpha-BGT, inhibits c...

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

authors： Quik M,Babu U,Audhya T,Goldstein G

更新日期：1991-03-15 00:00:00

abstract：:Melanomas occur mainly in sunlight-exposed skin. Xeroderma pigmentosum (XP) patients have 1,000-fold higher incidence of melanoma, suggesting that sunlight-induced "bulky" photoproducts are responsible for melanomagenesis. Sunlight induces a high level of reactive oxygen species in melanocytes (MCs); oxidative DNA dam...

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

authors： Wang HT,Choi B,Tang MS

更新日期：2010-07-06 00:00:00

abstract：:Posttranslational modifications (PTMs) are important physiological means to regulate the activities and structures of central regulatory proteins in health and disease. Small GTPases have been recognized as important molecules that are targeted by PTMs during infections of mammalian cells by bacterial pathogens. The e...

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

authors： Barthelmes K,Ramcke E,Kang HS,Sattler M,Itzen A

更新日期：2020-03-17 00:00:00

abstract：:Cancer vaccines genetically engineered to produce interleukin 2 have been investigated intensively in a series of animal models and are at the point of entering into clinical trials. In this study we demonstrate a strong correlation between the rate of interleukin 2 production and the protection efficiency of murine S...

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

authors： Schmidt W,Schweighoffer T,Herbst E,Maass G,Berger M,Schilcher F,Schaffner G,Birnstiel ML

更新日期：1995-05-09 00:00:00

abstract：:In that salmonellae have been implicated in an unprecedented array of diseases, sequences found to be specific to this species are often thought to be involved in the virulence attributes not seen in other enteric bacteria. To identify the molecular, genetic, and phenotypic characteristics that differentiate bacterial...

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

authors： Groisman EA,Sturmoski MA,Solomon FR,Lin R,Ochman H

更新日期：1993-02-01 00:00:00

abstract：:Mammalian reproductive function depends upon a neuroendocrine circuit that evokes the pulsatile release of gonadotropin hormones (luteinizing hormone and follicle-stimulating hormone) from the pituitary. This reproductive circuit is sensitive to metabolic perturbations. When challenged with starvation, insufficient en...

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

authors： Padilla SL,Qiu J,Nestor CC,Zhang C,Smith AW,Whiddon BB,Rønnekleiv OK,Kelly MJ,Palmiter RD

更新日期：2017-02-28 00:00:00

abstract：:Microcin B17 (MccB17) is a 3.1-kDa Escherichia coli antibiotic that contains thiazole and oxazole heterocycles in a peptide backbone. MccB17 inhibits its cellular target, DNA gyrase, by trapping the enzyme in a complex that is covalently bound to double-strand cleaved DNA, in a manner similar to the well-known quinolo...

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

authors： Zamble DB,Miller DA,Heddle JG,Maxwell A,Walsh CT,Hollfelder F

更新日期：2001-07-03 00:00:00

abstract：:Genetic screens have been performed to identify mutants with altered auxin homeostasis in Arabidopsis. A tagged allele of the auxin-overproducing mutant sur2 was identified within a transposon mutagenized population. The SUR2 gene was cloned and shown to encode the CYP83B1 protein, which belongs to the large family of...

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

authors： Barlier I,Kowalczyk M,Marchant A,Ljung K,Bhalerao R,Bennett M,Sandberg G,Bellini C

更新日期：2000-12-19 00:00:00

abstract：:RNA-binding motif protein 4 (RBM4) plays a regulatory role in alternative splicing of precursor mRNA. We show here that cell stress such as arsenite exposure induces phosphorylation of RBM4 at serine 309 and also drives its cytoplasmic accumulation and targeting to stress granule via the MKK(3/6)-p38 signaling pathway...

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

authors： Lin JC,Hsu M,Tarn WY

更新日期：2007-02-13 00:00:00

abstract：:To elucidate the molecular mechanism of frameshift suppression by the SUF2 gene of yeast, the sequences of DNA fragments carrying the SUF2-1 and suf2+ alleles of the gene and surrounding regions have been determined. Comparison of the suppressor and wild-type sequences indicates that the SUF2 gene product is a proline...

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

authors： Cummins CM,Donahue TF,Culbertson MR

更新日期：1982-06-01 00:00:00

abstract：:One of the fundamental events in metamorphosis in insects is the replacement of larval tissues by imaginal tissues. Shortly after pupariation the imaginal discs evaginate to assume their positions at the surface of the prepupal animal. This is a very precise process that is only beginning to be understood. In Drosophi...

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

authors： Martin-Blanco E,Pastor-Pareja JC,Garcia-Bellido A

更新日期：2000-07-05 00:00:00

abstract：:Oxidants, such as those generated by metabolically activated phagocytes in inflammation, have been implicated in the metabolic activation of carcinogens, and in this study we demonstrate that the interaction of (+/-)-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (BP 7,8-dihydrodiol) with phorbol ester-stimulated polym...

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

authors： Trush MA,Seed JL,Kensler TW

更新日期：1985-08-01 00:00:00

abstract：:The conformational effects of different amino acid substitutions (lysine, serine, proline, and D-valine) for glycine at position 12 in the p21 oncogene-encoded proteins have been investigated by using conformational energy calculations. The normal cellular gene codes for a glycine at position 12 in the amino acid sequ...

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

authors： Pincus MR,Brandt-Rauf PW

更新日期：1985-06-01 00:00:00

abstract：:When spores of the anaerobic bacterium Clostridium novyi-NT are systemically injected into animals, they germinate exclusively within the hypoxic regions of cancers. The germinated bacteria destroy adjacent tumor cells but spare a rim of well oxygenated tumor cells that subsequently expand. Surprisingly, we found that...

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

authors： Agrawal N,Bettegowda C,Cheong I,Geschwind JF,Drake CG,Hipkiss EL,Tatsumi M,Dang LH,Diaz LA Jr,Pomper M,Abusedera M,Wahl RL,Kinzler KW,Zhou S,Huso DL,Vogelstein B

更新日期：2004-10-19 00:00:00

abstract：:Like many other social phenomena, prostitution is increasingly coordinated over the Internet. The online behavior affects the offline activity; the reverse is also true. We investigated the reported sexual contacts between 6,624 anonymous escorts and 10,106 sex buyers extracted from an online community from its beginn...

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

authors： Rocha LE,Liljeros F,Holme P

更新日期：2010-03-30 00:00:00

abstract：:The study of development has relied primarily on the isolation of mutations in genes with specific functions in development and on the comparison of their expression patterns in normal and mutant phenotypes. Comparative evolutionary analyses can complement these approaches. Phylogenetic analyses of Sonic hedgehog (Shh...

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

authors： Zardoya R,Abouheif E,Meyer A

更新日期：1996-11-12 00:00:00

abstract：:Vaccination has been used to control the spread of seasonal flu; however, the virus continues to evolve and escape from host immune response through mutation and increasing glycosylation. Efforts have been directed toward development of a universal vaccine with broadly protective activity against multiple influenza st...

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

authors： Liao HY,Wang SC,Ko YA,Lin KI,Ma C,Cheng TR,Wong CH

更新日期：2020-07-28 00:00:00

abstract：:Most HLA haplotypes carry two expressed DR beta-chain genes; in the DR4 haplotype, the polymorphic locus has been called DR beta 1 and the apparently nonpolymorphic locus has been called DR beta 2. We have isolated nearly full-length DR beta-chain cDNA clones representing each of these two loci from a cell line homozy...

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

authors： Curtsinger JM,Hilden JM,Cairns JS,Bach FH

更新日期：1987-01-01 00:00:00

abstract：:Misalignment between internal circadian rhythmicity and externally imposed behavioral schedules, such as occurs in shift workers, has been implicated in elevated risk of metabolic disorders. To determine underlying mechanisms, it is essential to assess whether and how peripheral clocks are disturbed during shift work ...

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

authors： Skene DJ,Skornyakov E,Chowdhury NR,Gajula RP,Middleton B,Satterfield BC,Porter KI,Van Dongen HPA,Gaddameedhi S

更新日期：2018-07-24 00:00:00

abstract：:Integrin-dependent adhesions mediate reciprocal exchange of force and information between the cell and the extracellular matrix. These effects are attributed to the "focal adhesion clutch," in which moving actin filaments transmit force to integrins via dynamic protein interactions. To elucidate these processes, we me...

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

authors： Driscoll TP,Ahn SJ,Huang B,Kumar A,Schwartz MA

更新日期：2020-12-22 00:00:00

abstract：:DsRed, a brilliantly red fluorescent protein, was recently cloned from Discosoma coral by homology to the green fluorescent protein (GFP) from the jellyfish Aequorea. A core question in the biochemistry of DsRed is the mechanism by which the GFP-like 475-nm excitation and 500-nm emission maxima of immature DsRed are r...

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

authors： Gross LA,Baird GS,Hoffman RC,Baldridge KK,Tsien RY

更新日期：2000-10-24 00:00:00

abstract：:Cell adhesion molecules (CAMs) are cell surface glycoproteins that may play a variety of roles in morphogenesis and histogenesis, particularly in defining borders of discrete cell populations. To examine the influence of CAM expression on such cell segregation events in vitro, we have transfected cells with cDNAs codi...

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

authors： Friedlander DR,Mège RM,Cunningham BA,Edelman GM

更新日期：1989-09-01 00:00:00

abstract：:The eyes of some aquatic animals form images through reflective optics. Shrimp, lobsters, crayfish, and prawns possess reflecting superposition compound eyes, composed of thousands of square-faceted eye units (ommatidia). Mirrors in the upper part of the eye (the distal mirror) reflect light collected from many ommati...

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

authors： Palmer BA,Hirsch A,Brumfeld V,Aflalo ED,Pinkas I,Sagi A,Rosenne S,Oron D,Leiserowitz L,Kronik L,Weiner S,Addadi L

更新日期：2018-03-06 00:00:00

abstract：:In this study, we quantified 249 mature micro-RNA (miRNA) transcripts in estrogen receptor-positive (ER(+)) primary breast tumors of patients with lymph node-negative (LNN) disease to identify miRNAs associated with metastatic capability. In addition, the prognostic value of the candidate miRNAs was determined in ER(-...

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

authors： Foekens JA,Sieuwerts AM,Smid M,Look MP,de Weerd V,Boersma AW,Klijn JG,Wiemer EA,Martens JW

更新日期：2008-09-02 00:00:00

abstract：:Knowledge of the mechanisms by which a cell detects exogenous DNA is important for controlling pathogen infection, because most pathogens entail the presence of exogenous DNA in the cytosol, as well as for understanding the cell's response to artificially transfected DNA. The cellular response to pathogen invasion has...

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

authors： Kobayashi S,Koujin T,Kojidani T,Osakada H,Mori C,Hiraoka Y,Haraguchi T

更新日期：2015-06-02 00:00:00