A soluble domain of the membrane-anchoring chain of influenza virus hemagglutinin (HA2) folds in Escherichia coli into the low-pH-induced conformation.

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：:Improving global yields of important agricultural crops is a complex challenge. Enhancing yield and resource use by engineering improvements to photosynthetic carbon assimilation is one potential solution. During the last 40 million years C(4) photosynthesis has evolved multiple times, enabling plants to evade the cat...

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

authors： Whitney SM,Sharwood RE,Orr D,White SJ,Alonso H,Galmés J

更新日期：2011-08-30 00:00:00

abstract：:Soybean plants and Rhizobium japonicum 122 DES, a hydrogen uptake-positive strain, were cultured in media purified to remove Ni. Supplemental Ni had no significant effect on the dry matter or total N content of plants. However, the addition of Ni to both nitrate-grown and symbiotically grown plants resulted in a 7- to...

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

authors： Klucas RV,Hanus FJ,Russell SA,Evans HJ

更新日期：1983-04-01 00:00:00

abstract：:The polyomavirus enhancer is composed of multiple DNA sequence elements serving as binding sites for proteins present in mouse nuclear extracts that activate transcription and DNA replication. We have identified three such proteins and their binding sites and correlate them with enhancer function. Mutation of nucleoti...

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

authors： Martin ME,Piette J,Yaniv M,Tang WJ,Folk WR

更新日期：1988-08-01 00:00:00

abstract：:Most current gene transfer methods function satisfactorily in specialized systems involving established cell lines but are often not applicable with nonadherent, primary hematopoietic cells, which are notoriously difficult to transfect. To approach this problem, we have investigated an alternative method of gene trans...

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

authors： Zenke M,Steinlein P,Wagner E,Cotten M,Beug H,Birnstiel ML

更新日期：1990-05-01 00:00:00

abstract：:Infection during the neonatal period commonly induces apnea episodes, and the proinflammatory cytokine IL-1beta may serve as a critical mediator between these events. To determine the mechanism by which IL-1beta depresses respiration, we examined a prostaglandin E(2) (PGE(2))-dependent pathway in newborn mice and huma...

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

authors： Hofstetter AO,Saha S,Siljehav V,Jakobsson PJ,Herlenius E

更新日期：2007-06-05 00:00:00

abstract：:The exemplary search capabilities of flying insects have established them as one of the most diverse taxa on Earth. However, we still lack the fundamental ability to quantify, represent, and predict trajectories under natural contexts to understand search and its applications. For example, flying insects have evolved ...

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

authors： Kaushik PK,Renz M,Olsson SB

更新日期：2020-06-02 00:00:00

abstract：:Class I major histocompatibility complex (MHC) antigens are confronted with an apparently insurmountable dilemma. Each should show a binding preference to a common enough variety of nonapeptides, so that one relevant nonapeptide can be found in at least every other viral protein to provoke a cytotoxic T-cell response....

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

authors： Ohno S

更新日期：1992-05-15 00:00:00

abstract：:Soret-excited resonance Raman spectroscopy yields direct information regarding the iron-carbon bonding interactions in the cyanomet and carbonmonoxy complexes of hemoglobin III from Chironomus thummi thummi (CTT III) in solution. By isotope exchange in cyanide (13CN-, C15N-, and 13C15N-) and carbon monoxide (13CO, C18...

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

authors： Yu NT,Benko B,Kerr EA,Gersonde K

更新日期：1984-08-01 00:00:00

abstract：:The maximum rate of expression of the lac operon is severely reduced in lac promoter mutants. Revertants of these mutations which produce higher levels of enzyme were isolated. Some of these revertants had lost sensitivity to catabolite repression and transient repression. The mutations responsible for these losses to...

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

authors： Silverstone AE,Arditti RR,Magasanik B

更新日期：1970-07-01 00:00:00

abstract：:The transcription of genes encoding gluconeogenic enzymes is tightly regulated during the perinatal period. These genes are induced by glucagon (cAMP) and glucocorticoids and repressed by insulin. To address the role of cAMP and glucocorticoids in the physiological activation of genes encoding gluconeogenic enzymes in...

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

authors： Montoliu L,Blendy JA,Cole TJ,Schütz G

更新日期：1995-05-09 00:00:00

abstract：:Despite high predation pressure, planktonic copepods remain one of the most abundant groups on the planet. Their escape response provides one of most effective mechanisms to maximize evolutionary fitness. Owing to their small size (100 µm) compared with their predators (>1 mm), increasing viscosity is believed to have...

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

authors： Gemmell BJ,Sheng J,Buskey EJ

更新日期：2013-03-19 00:00:00

abstract：:Photonic materials with positionally ordered structure can interact strongly with light to produce brilliant structural colors. Here, we found that the nonperiodic nematic liquid crystals of nanoplates can also display structural color with only significant orientational order. Owing to the loose stacking of the nemat...

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

authors： Zeng M,King D,Huang D,Do C,Wang L,Chen M,Lei S,Lin P,Chen Y,Cheng Z

更新日期：2019-09-10 00:00:00

abstract：:Jasmonoyl-isoleucine (JA-Ile), the active form of the plant hormone jasmonate (JA), is sensed by the F-box protein CORONATINE INSENSITIVE 1 (COI1), a component of a functional Skp-Cullin-F-box E3 ubiquitin ligase complex. Sensing of JA-Ile by COI1 rapidly triggers genome-wide transcriptional changes that are largely r...

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

authors： An C,Li L,Zhai Q,You Y,Deng L,Wu F,Chen R,Jiang H,Wang H,Chen Q,Li C

更新日期：2017-10-17 00:00:00

abstract：:Attention to a stimulus enhances both neuronal responses and gamma frequency synchrony in visual area V4, both of which should increase the impact of attended information on downstream neurons. To determine whether gamma synchrony is common throughout the ventral stream, we recorded from neurons in the superficial and...

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

authors： Buffalo EA,Fries P,Landman R,Buschman TJ,Desimone R

更新日期：2011-07-05 00:00:00

abstract：:A previous study demonstrated that the translational inhibitor from lysates of heme-deficient rabbit reticulocytes is associated with a protein kinase activity. Chromatography of this inhibitor preparation on phosphocellulose yields two distinct protein kinase activities, PC1 and PC2. PC1, which consitutes about 90% o...

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

authors： Levin D,Ranu RS,Ernst V,London IM

更新日期：1976-09-01 00:00:00

abstract：:We have isolated a major integral membrane protein from Golgi-derived coatomer-coated vesicles. This 24-kDa protein, p24, defines a family of integral membrane proteins with homologs present in yeast and humans. In addition to sequence similarity, all p24 family members contain a motif with the characteristic heptad r...

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

authors： Stamnes MA,Craighead MW,Hoe MH,Lampen N,Geromanos S,Tempst P,Rothman JE

更新日期：1995-08-15 00:00:00

abstract：:Transport of L-glutamine and of the chloroketone glutamine analog L-2-amino-4-oxo-5-chloropentanoate into lymphoid cells is mediated by the same system. Arginine and a number of other amino acids (e.g., glutamate, aspartate, and lysine) are transported to a much lesser extent by this system. However, after uptake of t...

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

authors： Novogrodsky A,Nehring RE Jr,Meister A

更新日期：1979-10-01 00:00:00

abstract：:The strong consistency of least squares estimates in multiple regression models with independent errors is obtained under minimal assumptions on the design and weak moment conditions on the errors. ...

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

authors： Lai TL,Robbins H,Wei CZ

更新日期：1978-07-01 00:00:00

abstract：:Retinoblastoma-related (RBR) genes inhibit the cell cycle primarily by repressing adenovirus E2 promoter binding factor (E2F) transcription factors, which drive the expression of numerous genes required for DNA synthesis and cell cycle progression. The RBR-E2F pathway is conserved in plants, but cereals such as maize ...

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

authors： Sabelli PA,Hoerster G,Lizarraga LE,Brown SW,Gordon-Kamm WJ,Larkins BA

更新日期：2009-03-10 00:00:00

abstract：:During protein synthesis, elongation factor G (EF-G) binds to the ribosome and promotes the step of translocation, a process in which tRNA moves from the A to the P site of the ribosome and the mRNA is advanced by one codon. By using three-dimensional cryo-electron microscopy, we have visualized EF-G in a ribosome-EF-...

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

authors： Agrawal RK,Penczek P,Grassucci RA,Frank J

更新日期：1998-05-26 00:00:00

abstract：:In Salmonella typhimurium, the CobU, CobS, CobT, and CobC proteins have been proposed to catalyze the late steps in adenosylcobalamin biosynthesis, which define the nucleotide loop assembly pathway. This paper reports the in vitro assembly of the nucleotide loop of adenosylcobalamin from its precursors adenosylcobinam...

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

authors： Maggio-Hall LA,Escalante-Semerena JC

更新日期：1999-10-12 00:00:00

abstract：:Apoptotic cells contain nuclear autoantigens that may initiate a systemic autoimmune response. To explore the mechanism of antibody binding to apoptotic cells, 3H9, a murine autoantibody with dual specificity for phospholipids and DNA, was used. H chain mutants of 3H9 were constructed, expressed as single-chain Fv (sc...

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

authors： Cocca BA,Seal SN,D'Agnillo P,Mueller YM,Katsikis PD,Rauch J,Weigert M,Radic MZ

更新日期：2001-11-20 00:00:00

abstract：:It is shown that, under certain standard assumptions, such as extended Riemann hypotheses, the scattering matrix varphi(s) for generic Gamma

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

authors： Deshouillers JM,Iwaniec H,Phillips RS,Sarnak P

更新日期：1985-06-01 00:00:00

abstract：:Recent experimental data on the equilibrium binding of myosin subfragment 1 (S-1) to regulated actin filaments in the presence and in the absence of Ca(2+) are analyzed by using a linear Ising model. In the model, each tropomyosin-troponin unit (including seven sites on the actin filament) can be in one of two possibl...

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

authors： Hill TL,Eisenberg E,Greene L

更新日期：1980-06-01 00:00:00

abstract：:Complementation of the plasmin fragments of reduced-carbamoylmethylated (Cam) human somatotropin (hGH) with those of reduced-carbamoylmethylated human chorionic somatomammotropin (hCS) have been investigated. It was found that the recombinant obtained by noncovalent interaction of [Cys(Cam)53]hGH-(1-134) with [Cys(Cam...

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

authors： Li CH

更新日期：1978-04-01 00:00:00

abstract：:A constitutively active form of mitogen-activated protein kinase kinase (MEK1) was synthesized under control of a zinc-inducible promoter in NIH 3T3 fibroblasts. Zinc treatment of serum-starved cells activated extracellular signal-regulated protein kinases (ERKs) and induced expression of cyclin D1. Newly synthesized ...

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

authors： Cheng M,Sexl V,Sherr CJ,Roussel MF

更新日期：1998-02-03 00:00:00

abstract：:It has been recently shown that malignant activation of the c-has/bas proto-oncogene in T24 human bladder carcinoma cells was mediated by a single point mutation. A deoxyguanosine located at position 35 of the first exon of this proto-oncogene was substituted by thymidine. These findings predicted that the resulting o...

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

authors： Santos E,Reddy EP,Pulciani S,Feldmann RJ,Barbacid M

更新日期：1983-08-01 00:00:00

abstract：:Iron-sulfur (Fe-S) proteins are key players in vital processes involving energy homeostasis and metabolism from the simplest to most complex organisms. We report a 1.5 A x-ray crystal structure of the first identified outer mitochondrial membrane Fe-S protein, mitoNEET. Two protomers intertwine to form a unique dimeri...

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

authors： Paddock ML,Wiley SE,Axelrod HL,Cohen AE,Roy M,Abresch EC,Capraro D,Murphy AN,Nechushtai R,Dixon JE,Jennings PA

更新日期：2007-09-04 00:00:00

abstract：:We have shown previously that hydroxyl radicals (HO*) can be produced by H2O2 and halogenated quinones, independent of transition metal ions; however, the underlying molecular mechanism is still unclear. In the present study, using the electron spin resonance secondary radical spin-trapping method, we found that tetra...

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

authors： Zhu BZ,Kalyanaraman B,Jiang GB

更新日期：2007-11-06 00:00:00