Colloquium paper: working toward a synthesis of archaeological, linguistic, and genetic data for inferring African population history.

abstract：:Polypeptide chains of 19 previously studied Escherichia coli aminoacyl-tRNA synthetases are as large as 951 amino acids and, depending on the enzyme, have quaternary structures of alpha, alpha 2, alpha 2 beta 2, and alpha 4. These enzymes have been organized into two classes which are defined by sequence motifs that a...

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

authors： Hou YM,Shiba K,Mottes C,Schimmel P

更新日期：1991-02-01 00:00:00

abstract：:A diverse range of neural cell types is generated from a pool of dividing stem and progenitor cells in an orderly manner during development. Little is known of the molecular and cellular biology underpinning the intrinsic control of this process. We have used a nonbiased method to purify populations of neural progenit...

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

authors： Livesey FJ,Young TL,Cepko CL

更新日期：2004-02-03 00:00:00

abstract：:Placental abnormalities occur frequently in cloned animals. Here, we attempted to isolate trophoblast stem (TS) cells from mouse blastocysts produced by somatic cell nuclear transfer (NT) at the blastocyst stage (NT blastocysts). Despite the predicted deficiency of the trophoblast cell lineage, we succeeded in isolati...

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

authors： Oda M,Tanaka S,Yamazaki Y,Ohta H,Iwatani M,Suzuki M,Ohgane J,Hattori N,Yanagimachi R,Wakayama T,Shiota K

更新日期：2009-09-22 00:00:00

abstract：:The temperature dependence of migration rate and of the thermotactic sensitivity of pseudoplasmodia of Dictyostelium discoideum has been measured. Migration rate increases with temperature to 20 degrees, is temperature insensitive from 20 degrees to 27.5 degrees, and decreases with temperature to 29 degrees, above whi...

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

authors： Poff KL,Skokut M

更新日期：1977-05-01 00:00:00

abstract：:The identification of genes contributing to the adaptation of local populations is of great biological interest. In an attempt to characterize functionally important differences among African and non-African Drosophila melanogaster populations, we surveyed neutral microsatellite variation in an 850-kb genomic sequence...

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

authors： Harr B,Kauer M,Schlötterer C

更新日期：2002-10-01 00:00:00

abstract：:Epidemics, flame propagation, and cardiac rhythms are classic examples of reaction-diffusion waves that describe a switch from one alternative state to another. Only two types of waves are known: pulled, driven by the leading edge, and pushed, driven by the bulk of the wave. Here, we report a distinct class of semipus...

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

authors： Birzu G,Hallatschek O,Korolev KS

更新日期：2018-04-17 00:00:00

abstract：:In confluent fibroblast monolayers, an increase in the selective uptake of free cholesterol (FC) from plasma low density lipoprotein (LDL) was accompanied by an increase in FC efflux. The rate of FC efflux was proportional to the FC content of the cell surface caveolae and to mRNA levels of caveolin, an FC-binding pro...

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

authors： Fielding CJ,Bist A,Fielding PE

更新日期：1997-04-15 00:00:00

abstract：:Seasonal epidemics and periodic worldwide pandemics caused by influenza A viruses are of continuous concern. The viral nonstructural (NS1) protein is a multifunctional virulence factor that antagonizes several host innate immune defenses during infection. NS1 also directly stimulates class IA phosphoinositide 3-kinase...

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

authors： Hale BG,Kerry PS,Jackson D,Precious BL,Gray A,Killip MJ,Randall RE,Russell RJ

更新日期：2010-02-02 00:00:00

abstract：:DNA synthesized in vitro from a phage M13 template has been cleaved at either guanine, adenine, or cytosine residues by ribosubstitution techniques. Fingerprints of the fragments obtained suggest that DNA sequencing will be possible with this technique. ...

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

authors： Salser W,Fry K,Brunk C,Poon R

更新日期：1972-01-01 00:00:00

abstract：:One of the defining trends of the Holocene has been the emergence of complex societies. Two essential features of complex societies are intensive resource use and sociopolitical hierarchy. Although it is widely agreed that these two phenomena are associated cross-culturally and have both contributed to the rise of com...

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

authors： Sheehan O,Watts J,Gray RD,Atkinson QD

更新日期：2018-04-03 00:00:00

abstract：:An increasing amount of investment has been devoted to protecting and restoring ecosystem services worldwide. The efficiency of conservation investments, including payments for ecosystem services (PES), has been found to be affected by biological, political, economic, demographic, and social factors, but little is kno...

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

authors： Chen X,Lupi F,He G,Liu J

更新日期：2009-07-14 00:00:00

abstract：:Human and murine MHC nonclassical class Ib-restricted invariant T (iT) cell subsets, such as invariant natural killer T cells (iNKT) and mucosal-associated invariant T cells, have specialized functions early in immune responses, especially in modulating subsequent adaptive immune responses. Here, we characterize a pro...

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

authors： Edholm ES,Albertorio Saez LM,Gill AL,Gill SR,Grayfer L,Haynes N,Myers JR,Robert J

更新日期：2013-08-27 00:00:00

abstract：:Egg activation is the process in which mature oocytes are released from developmental arrest and gain competency for embryonic development. In Drosophila and other arthropods, eggs are activated by mechanical pressure in the female reproductive tract, whereas in most other species, eggs are activated by fertilization....

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

authors： Hu Q,Wolfner MF

更新日期：2019-09-17 00:00:00

abstract：:NifEN is a key player in the biosynthesis of nitrogenase MoFe protein. It not only shares a considerable degree of sequence homology with the MoFe protein, but also contains clusters that are homologous to those found in the MoFe protein. Here we present an investigation of the catalytic activities of NifEN. Our data ...

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

authors： Hu Y,Yoshizawa JM,Fay AW,Lee CC,Wiig JA,Ribbe MW

更新日期：2009-10-06 00:00:00

abstract：:A gradual loss of telomeric repeat sequences with aging previously has been noted in normal adult tissues, and this process has been implicated in cell senescence. No data exist that address the rate of telomere shortening in normal human cells within families or early in life. To address these questions, we measured ...

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

authors： Frenck RW Jr,Blackburn EH,Shannon KM

更新日期：1998-05-12 00:00:00

abstract：:Monoclonal antibodies penetrate bulky tumors poorly after intravenous administration, in part because of specific binding to the target antigen. Experiments presented here demonstrate an analogous phenomenon in micrometastases; poor antibody penetration, attributable to a "binding-site barrier" phenomenon, can be seen...

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

authors： Saga T,Neumann RD,Heya T,Sato J,Kinuya S,Le N,Paik CH,Weinstein JN

更新日期：1995-09-12 00:00:00

abstract：:The Eastern Arc Mountains of Tanzania and the Atlantic Forest of Brazil are two of the most fragmented biodiversity hotspots. Species-area relationships predict that their habitat fragments will experience a substantial loss of species. Most of these extinctions will occur over an extended time, and therefore, reconne...

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

authors： Newmark WD,Jenkins CN,Pimm SL,McNeally PB,Halley JM

更新日期：2017-09-05 00:00:00

abstract：:Cardiac myosin-binding protein C (cMyBP-C) is an accessory protein of striated muscle sarcomeres that is vital for maintaining regular heart function. Its 4 N-terminal regulatory domains, C0-C1-m-C2 (C0C2), influence actin and myosin interactions, the basic contractile proteins of muscle. Using neutron contrast variat...

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

authors： Whitten AE,Jeffries CM,Harris SP,Trewhella J

更新日期：2008-11-25 00:00:00

abstract：:The commitment of differentiating cells to a specialized fate is fundamental to the correct assembly of tissues within a multicellular organism. Because commitment is often irreversible, entry into and progression through this phase of development must be tightly regulated. Under nitrogen-limiting conditions, the mult...

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

authors： Videau P,Rivers OS,Hurd K,Ushijima B,Oshiro RT,Ende RJ,O'Hanlon SM,Cozy LM

更新日期：2016-11-08 00:00:00

abstract：:Schaftoside and isoschaftoside are bioactive natural products widely distributed in higher plants including cereal crops and medicinal herbs. Their biosynthesis may be related with plant defense. However, little is known on the glycosylation biosynthetic pathway of these flavonoid di-C-glycosides with different sugar ...

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

authors： Wang ZL,Gao HM,Wang S,Zhang M,Chen K,Zhang YQ,Wang HD,Han BY,Xu LL,Song TQ,Yun CH,Qiao X,Ye M

更新日期：2020-12-01 00:00:00

abstract：:We visualized synchronous dynamic brain networks by using prewhitened (stationary) magnetoencephalography signals. Data were acquired from 248 axial gradiometers while 10 subjects fixated on a spot of light for 45 s. After fitting an autoregressive integrative moving average model and taking the residuals, all pairwis...

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

authors： Langheim FJ,Leuthold AC,Georgopoulos AP

更新日期：2006-01-10 00:00:00

abstract：:We used a high-titer recombinant adeno-associated virus (rAAV) vector to express WT or mutant human alpha-synuclein in the substantia nigra of adult marmosets. The alpha-synuclein protein was expressed in 90-95% of all nigral dopamine neurons and distributed by anterograde transport throughout their axonal and dendrit...

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

authors： Kirik D,Annett LE,Burger C,Muzyczka N,Mandel RJ,Björklund A

更新日期：2003-03-04 00:00:00

abstract：:Bioluminescence-based imaging of living cells has become an important tool in biological and medical research. However, many bioluminescence imaging applications are limited by the requirement of an externally provided luciferin substrate and the low bioluminescence signal which restricts the sensitivity and spatiotem...

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

authors： Gregor C,Pape JK,Gwosch KC,Gilat T,Sahl SJ,Hell SW

更新日期：2019-12-02 00:00:00

abstract：:The baculovirus Autographa californica nuclear polyhedrosis virus (AcMNPV, which is representative of the MNPV subtype in which the virions may contain many nucleocapsids within a single viral envelope) encodes a protein, v-ubi, that has 76% identity with the eukaryotic protein ubiquitin. Transcriptional mapping indic...

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

authors： Guarino LA

更新日期：1990-01-01 00:00:00

abstract：:The rates of spontaneous mutation to 6-thioguanine resistance were determined in fibroblasts derived from normal and two Bloom syndrome individuals (GM 2548 and GM 1492). Two methods were utilized to determine the rates. Method I obtained the spontaneous mutation rate from the increase in the mutation frequency of a c...

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

authors： Warren ST,Schultz RA,Chang CC,Wade MH,Trosko JE

更新日期：1981-05-01 00:00:00

abstract：:Congenital defects, trauma, and disease can compromise the integrity and functionality of the skeletal system to the extent requiring implantation of bone grafts. Engineering of viable bone substitutes that can be personalized to meet specific clinical needs represents a promising therapeutic alternative. The aim of o...

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

authors： de Peppo GM,Marcos-Campos I,Kahler DJ,Alsalman D,Shang L,Vunjak-Novakovic G,Marolt D

更新日期：2013-05-21 00:00:00

abstract：:The extracellular hemoglobin of Ascaris has an extremely high oxygen affinity (P50 = 0.004 mmHg). It consists of eight identical subunits of molecular weight 40,600. Their sequence, determined by protein chemistry, shows two tandemly linked globin-like sequences and an 18-residue C-terminal extension. Two N-linked gly...

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

authors： De Baere I,Liu L,Moens L,Van Beeumen J,Gielens C,Richelle J,Trotman C,Finch J,Gerstein M,Perutz M

更新日期：1992-05-15 00:00:00

abstract：:Bacteria have evolved the ability to produce a wide range of structurally complex natural products historically called "secondary" metabolites. Although some of these compounds have been identified as bacterial communication cues, more frequently natural products are scrutinized for antibiotic activities that are rele...

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

authors： Bleich R,Watrous JD,Dorrestein PC,Bowers AA,Shank EA

更新日期：2015-03-10 00:00:00

abstract：:Synapse formation at the neuromuscular junction (NMJ) requires an alternatively spliced variant of agrin (Z(+) agrin) that is produced only by neurons. Here, we show that Nova1 and Nova2, neuron-specific splicing factors identified as targets in autoimmune motor disease, are essential regulators of Z(+) agrin. Nova1/N...

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

authors： Ruggiu M,Herbst R,Kim N,Jevsek M,Fak JJ,Mann MA,Fischbach G,Burden SJ,Darnell RB

更新日期：2009-03-03 00:00:00

abstract：:Normal rat mast cells were stimulated by antibodies against IgE receptors (anti-RBL) or by anti-IgE, and [3H]methyl group incorporation into phospholipids, 45Ca uptake, and histamine release were examined. Anti-RBL or its F(ab')2 fragments and anti-IgE induced an increase in the incorporation of [3H]methyl into phosph...

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

authors： Ishizaka T,Hirata F,Ishizaka K,Axelrod J

更新日期：1980-04-01 00:00:00