A complex history of rearrangement in an orthologous region of the maize, sorghum, and rice genomes.

abstract：:Most natural populations are affected by seasonal changes in temperature, rainfall, or resource availability. Seasonally fluctuating selection could potentially make a large contribution to maintaining genetic polymorphism in populations. However, previous theory suggests that the conditions for multilocus polymorphis...

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

authors： Wittmann MJ,Bergland AO,Feldman MW,Schmidt PS,Petrov DA

更新日期：2017-11-14 00:00:00

abstract：:gamma-Aminobutyric acid type A (GABA-A) receptors are a major mediator of inhibitory neurotransmission in the mammalian central nervous system, and the site of action of a number of clinically important drugs. These receptors exist as a family of subtypes with distinct temporal and spatial patterns of expression and d...

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

authors： Bonnert TP,McKernan RM,Farrar S,le Bourdellès B,Heavens RP,Smith DW,Hewson L,Rigby MR,Sirinathsinghji DJ,Brown N,Wafford KA,Whiting PJ

更新日期：1999-08-17 00:00:00

abstract：:Human P-glycoprotein (Pgp) confers multidrug resistance to cancer cells by ATP-dependent extrusion of a great many structurally dissimilar hydrophobic compounds. The manner in which Pgp recognizes these different substrates is unknown. The protein shows internal homology between its N- and C-terminal halves, each comp...

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

authors： Dey S,Ramachandra M,Pastan I,Gottesman MM,Ambudkar SV

更新日期：1997-09-30 00:00:00

abstract：:The reactions catalyzed by Mo enzymes each find the product differing from the substrate by two electrons and two protons (or some multiple thereof). The coordination chemistry of Mo suggests that there is a distinct relationship between acid-base and redox properties of Mo complexes, and that a coupled electron-proto...

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

authors： Stiefel EI

更新日期：1973-04-01 00:00:00

abstract：:The insulin signaling pathway is of pivotal importance in metabolic diseases, such as diabetes, and in cellular processes, such as aging. Insulin activates a tyrosine phosphorylation cascade that branches to create a complex network affecting multiple biological processes. To understand the full spectrum of the tyrosi...

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

authors： Krüger M,Kratchmarova I,Blagoev B,Tseng YH,Kahn CR,Mann M

更新日期：2008-02-19 00:00:00

abstract：:In a posterior silk gland extract, covalently closed circular (ccc) DNA is in a superhelical state that supports more transcription of fibroin gene than does linear DNA. A HeLa cell extract showed neither the supercoiling activity nor the preference for the transcription of ccc DNA over linear DNA. These activities co...

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

authors： Hirose S,Suzuki Y

更新日期：1988-02-01 00:00:00

abstract：:Molecular recognition by proteins is fundamental to molecular biology. Dissection of the thermodynamic energy terms governing protein-ligand interactions has proven difficult, with determination of entropic contributions being particularly elusive. NMR relaxation measurements have suggested that changes in protein con...

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

authors： Caro JA,Harpole KW,Kasinath V,Lim J,Granja J,Valentine KG,Sharp KA,Wand AJ

更新日期：2017-06-20 00:00:00

abstract：:COVID-19 has emerged as one of the deadliest and most disruptive events in recent human history. Drawing from political science and psychological theories, we examine the effects of daily confirmed cases in a country on citizens' support for the political leader through the first 120 d of 2020. Using three unique data...

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

authors： Yam KC,Jackson JC,Barnes CM,Lau J,Qin X,Lee HY

更新日期：2020-10-13 00:00:00

abstract：:Eccentricity, obliquity, and precession are cyclic parameters of the Earth's orbit whose climatic implications have been widely demonstrated on recent and short time intervals. Amplitude modulations of these parameters on million-year time scales induce "grand orbital cycles," but the behavior and the paleoenvironment...

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

authors： Martinez M,Dera G

更新日期：2015-10-13 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：:Aerosols impact climate, human health, and the chemistry of the atmosphere, and aerosol pH plays a major role in the physicochemical properties of the aerosol. However, there remains uncertainty as to whether aerosols are acidic, neutral, or basic. In this research, we show that the pH of freshly emitted (nascent) sea...

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

authors： Angle KJ,Crocker DR,Simpson RMC,Mayer KJ,Garofalo LA,Moore AN,Mora Garcia SL,Or VW,Srinivasan S,Farhan M,Sauer JS,Lee C,Pothier MA,Farmer DK,Martz TR,Bertram TH,Cappa CD,Prather KA,Grassian VH

更新日期：2021-01-12 00:00:00

abstract：:The serological properties of the gag gene products p15 and p12 of N- and B-tropic viruses of C57BL mice have been examined. Although these viruses were serologically identical by competition assays for proteins gp71 and p30, they were readily distinguishable in competition assays for proteins p15 and p12. Two isolate...

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

authors： Benade LE,Ihle JN,Declève A

更新日期：1978-09-01 00:00:00

abstract：:Let t --> gamma(t) be a homogeneous curve in R(n). For suitable f, define [unk](f)(x) = sup(h > 0)|(1/h) [unk](0) (h)f(x - gamma(t)) dt|. Then parallel[unk](f) parallel(p)

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

authors： Stein EM

更新日期：1976-07-01 00:00:00

abstract：:Helper-dependent adenoviral vectors deleted of all viral coding sequences have shown an excellent gene expression profile in a variety of animal models, as well as a reduced toxicity after systemic delivery. What is still unclear is whether long-term expression and therapeutic dosages of these vectors can be obtained ...

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

authors： Maione D,Della Rocca C,Giannetti P,D'Arrigo R,Liberatoscioli L,Franlin LL,Sandig V,Ciliberto G,La Monica N,Savino R

更新日期：2001-05-22 00:00:00

abstract：:In previous studies we showed that 5 days of treatment with granulocyte colony-stimulating factor (G-CSF) and stem cell factor (SCF) mobilized murine repopulating cells to the peripheral blood (PB) and that these cells could be efficiently transduced with retroviral vectors. We also found that, 7-14 days after cytokin...

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

authors： Dunbar CE,Seidel NE,Doren S,Sellers S,Cline AP,Metzger ME,Agricola BA,Donahue RE,Bodine DM

更新日期：1996-10-15 00:00:00

abstract：:The molecular mechanism of desensitization of soluble guanylyl cyclase (sGC), the NO receptor, has long remained unresolved. Posttranslational modification and redox state have been postulated to affect sGC sensitivity to NO but evidence has been lacking. We now show that sGC can be S-nitrosylated in primary aortic sm...

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

authors： Sayed N,Baskaran P,Ma X,van den Akker F,Beuve A

更新日期：2007-07-24 00:00:00

abstract：:Wild-type Escherichia coli cells grow normally in 95% O(2)/5% CO(2). In contrast, cells that cannot make polyamines because of mutations in the biosynthetic pathway are rapidly killed by incubation in 95% O(2)/5% CO(2). Addition of polyamines prevents the toxic effect of oxygen, permitting cell survival and optimal gr...

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

authors： Chattopadhyay MK,Tabor CW,Tabor H

更新日期：2003-03-04 00:00:00

abstract：:The herpes simplex virus DNA polymerase consists of two subunits--a catalytic subunit and an accessory subunit, UL42, that increases processivity. Mutations affecting the extreme C terminus of the catalytic subunit specifically disrupt subunit interactions and ablate virus replication, suggesting that new antiviral dr...

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

authors： Digard P,Williams KP,Hensley P,Brooks IS,Dahl CE,Coen DM

更新日期：1995-02-28 00:00:00

abstract：:RNA viruses are notorious for their genetic plasticity and propensity to exploit new host-range opportunities, which can lead to the emergence of human disease epidemics such as severe acute respiratory syndrome, AIDS, dengue, and influenza. However, the mechanisms of host-range change involved in most of these viral ...

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

authors： Anishchenko M,Bowen RA,Paessler S,Austgen L,Greene IP,Weaver SC

更新日期：2006-03-28 00:00:00

abstract：:The ability to grow the marine molluse Aplysia under laboratory conditions allows a detailed study of the formation of the nervous system and of the development of specific identified cells. I have found that the ganglia develop in a specific temporal order. Cerebral and pedal ganglia develop at hatching, the abdomina...

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

authors： Kriegstein AR

更新日期：1977-01-01 00:00:00

abstract：:Acanthamoeba castellanii contains two enzymes, myosins IA and IB, that exhibit the catalytic properties of a myosin but possess very unusual physical properties, the most striking of which are their single, low molecular weight heavy chain, their globular shape, and their inability to form bipolar filaments. We have n...

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

authors： Hammer JA 3rd,Jung G,Korn ED

更新日期：1986-07-01 00:00:00

abstract：:Changes in cyclic nucleotide metabolism similar to those characteristic of the chronic forms of hypertension were observed in an acute neurogenic form of hypertension in rats produced by electrolytic lesions of the nucleus tractus solitarii. These changes that were evident 2 hr after the lesions were made included dec...

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

authors： Amer MS,Doba N,Reis DJ

更新日期：1975-06-01 00:00:00

abstract：:Production of mature erythrocytes requires multiple growth factors, but we do not know how their actions are coordinated. Here we show that erythroid progenitors from erythropoietin receptor (Epo-R)-/- fetal livers, infected in vitro with a retrovirus expressing the wild-type Epo-R, require addition of both Epo and st...

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

authors： Wu H,Klingmüller U,Acurio A,Hsiao JG,Lodish HF

更新日期：1997-03-04 00:00:00

abstract：:Helicobacter pylori is a Gram-negative bacterial pathogen with a small genome of 1.64-1.67 Mb. More than 20 putative DNA restriction-modification (R-M) systems, comprising more than 4% of the total genome, have been identified in the two completely sequenced H. pylori strains, 26695 and J99, based on sequence similari...

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

authors： Lin LF,Posfai J,Roberts RJ,Kong H

更新日期：2001-02-27 00:00:00

abstract：:Targeting and innervation of the cerebral cortex by thalamic afferents is a key event in the specification of cortical areas. The molecular targets of thalamic regulation, however, have remained elusive. We now demonstrate that thalamic afferents regulate the expression of gamma-aminobutyric acid type A (GABAA) recept...

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

authors： Paysan J,Kossel A,Bolz J,Fritschy JM

更新日期：1997-06-24 00:00:00

abstract：:We have previously observed the spontaneous, pH-dependent insertion of a water-soluble peptide to form a helix across lipid bilayers [Hunt, J. F., Rath, P., Rothschild, K. J. & Engelman, D. M. (1997) Biochemistry 36, 15177-15192]. We now use a related peptide, pH (low) insertion peptide, to translocate cargo molecules...

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

authors： Reshetnyak YK,Andreev OA,Lehnert U,Engelman DM

更新日期：2006-04-25 00:00:00

abstract：:An increasing number of protein structures are found to encompass multiple folding nuclei, allowing their structures to be formed by several competing pathways. A typical example is the ribosomal protein S6, which comprises two folding nuclei (sigma1 and sigma2) defining two competing pathways in the folding energy la...

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

authors： Haglund E,Lind J,Oman T,Ohman A,Mäler L,Oliveberg M

更新日期：2009-12-22 00:00:00

abstract：:There has been much confusion recently about the relative merits of different approaches, osmotic stress, preferential interaction, and crowding, to describe the indirect effect of solutes on macromolecular conformations and reactions. To strengthen all interpretations of measurements and to forestall further unnecess...

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

authors： Parsegian VA,Rand RP,Rau DC

更新日期：2000-04-11 00:00:00

abstract：:The specificity of human skin collagenase and of an enzyme from an invasive tumor were studied by using types I, II, III, IV, and V (AB) collagen as substrates. Human skin collagenase degraded types I, II, and III collagen, producing the characteristic 3/4 and 1/4 cleavage products, but failed to degrade type IV or V ...

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

authors： Liotta LA,Abe S,Robey PG,Martin GR

更新日期：1979-05-01 00:00:00

abstract：:When deprived of D-glucose for 24 hr, chicken embryo fibroblasts exhibit a marked increase in hexose transport activity compared with that of control cells. Scatchard analysis of [3H]cytochalasin B binding to starved cell plasma membranes (46 pmol/mg) indicated a six-fold increase compared with fed cell plasma membran...

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

authors： Pessin JE,Tillotson LG,Yamada K,Gitomer W,Carter-Su C,Mora R,Isselbacher KJ,Czech MP

更新日期：1982-04-01 00:00:00