Abstract:
:The origin of the two-phase (cap, no cap) macroscopic kinetic model of the end of a microtubule is reviewed. The model is then applied to a new theoretical problem, namely, the Mitchison-Kirschner [Mitchison, T. & Kirschner, M. W. (1984) Nature (London) 312, 237-242] experiment in which aggregated microtubules in solution spontaneously decrease in number (shorten to disappearance) while the surviving microtubules increase in length. The model fits the experiments without difficulty.
journal_name
Proc Natl Acad Sci U S Aauthors
Chen Y,Hill TLdoi
10.1073/pnas.82.12.4127subject
Has Abstractpub_date
1985-06-01 00:00:00pages
4127-31issue
12eissn
0027-8424issn
1091-6490journal_volume
82pub_type
杂志文章abstract::Ouabain-sensitive uncoupled Na+ efflux has been studied in human, pig, and rat red cells and in vesicles containing reconstituted kidney Na+/K+ pumps obtained from these same species. The red cells from the different species gave qualitatively similar results; the uncoupled Na+ efflux was 15-30% of the Na+/K+ exchange...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.91.21.9881
更新日期:1994-10-11 00:00:00
abstract::Here, using further optimized 3D culture that allows highly selective induction and long-term growth of human ES cell (hESC)-derived cortical neuroepithelium, we demonstrate unique aspects of self-organization in human neocorticogenesis. Self-organized cortical tissue spontaneously forms a polarity along the dorsocaud...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1315710110
更新日期:2013-12-10 00:00:00
abstract::Granulocytes generate a "respiratory burst" of NADPH oxidase-dependent superoxide anion (O(2)(-*)) production that is required for efficient clearance of bacterial pathogens. Hv1 mediates a voltage-gated H(+) channel activity that is proposed to serve a charge-balancing role in granulocytic phagocytes such as neutroph...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0902761106
更新日期:2009-05-05 00:00:00
abstract::One of the earliest detectable events during plant-pathogen interaction is a rapid increase in ethylene biosynthesis. This gaseous plant stress hormone may be a signal for plants to activate defense mechanisms against invading pathogens such as bacteria, fungi, and viruses. The effect of ethylene on four plant genes i...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.84.15.5202
更新日期:1987-08-01 00:00:00
abstract::Dopamine is believed to contribute to the degeneration of dopamine-containing neurons in the brain. However, whether dopamine affects the survival of other neuronal populations has remained unclear. Here we document that mice with persistently elevated extracellular dopamine, resulting from inactivation of the dopamin...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1831768100
更新日期:2003-09-16 00:00:00
abstract::The majority of outer membrane proteins (OMPs) from gram-negative bacteria and many of mitochondria and chloroplasts are β-barrels. Insertion and assembly of these proteins are catalyzed by the Omp85 protein family in a seemingly conserved process. All members of this family exhibit a characteristic N-terminal polypep...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1108626108
更新日期:2011-08-16 00:00:00
abstract::Seep sediments are dominated by intensive microbial sulfate reduction coupled to the anaerobic oxidation of methane (AOM). Through geochemical measurements of incubation experiments with methane seep sediments collected from Hydrate Ridge, we provide insight into the role of iron oxides in sulfate-driven AOM. Seep sed...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1412269111
更新日期:2014-10-07 00:00:00
abstract::The E6 protein of the high-risk human papillomaviruses inactivates the tumor suppressor protein p53 by stimulating its ubiquitinylation and subsequent degradation. Ubiquitinylation is a multistep process involving a ubiquitin-activating enzyme, one of many distinct ubiquitin-conjugating enzymes, and in certain cases, ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.92.8.3264
更新日期:1995-04-11 00:00:00
abstract::Apicomplexan parasites replicate within a protective organelle, called the parasitophorous vacuole (PV). The Toxoplasma gondii PV is filled with a network of tubulated membranes, which are thought to facilitate trafficking of effectors and nutrients. Despite being critical to parasite virulence, there is scant mechani...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1816161116
更新日期:2019-03-26 00:00:00
abstract::Alterations in serotonin (5-hydroxytriptamine, 5-HT), norepinephrine, and gamma-aminobutyric acid have been linked to the pathophysiology of anxiety and depression, and medications that modulate these neurotransmitters are widely used to treat mood disorders. Recently, the neuropeptide substance P (SP) and its recepto...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.041596398
更新日期:2001-02-13 00:00:00
abstract::A "supercooled" liquid develops when a fluid does not crystallize upon cooling below its ordering temperature. Instead, the microscopic relaxation times diverge so rapidly that, upon further cooling, equilibration eventually becomes impossible and glass formation occurs. Classic supercooled liquids exhibit specific id...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1511006112
更新日期:2015-07-14 00:00:00
abstract::Total chemical synthesis was used to prepare the mirror image (D-protein) form of the angiogenic protein vascular endothelial growth factor (VEGF-A). Phage display against D-VEGF-A was used to screen designed libraries based on a unique small protein scaffold in order to identify a high affinity ligand. Chemically syn...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1210483109
更新日期:2012-09-11 00:00:00
abstract::DNA-membrane attachment in cultures of E. coli B/r is found to depend on the pattern of DNA synthesis, (a) When the number of replication points increases, the fraction of the DNA that is membrane bound also increases. The relationship between the amount of DNA-membrane attachment and the number of replication points ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.72.6.2446
更新日期:1975-06-01 00:00:00
abstract::Delta5 and Delta6 fatty acid desaturases are critical enzymes in the pathways for the biosynthesis of the polyunsaturated fatty acids arachidonic, eicosapentaenoic, and docosahexaenoic acids. They are encoded by distinct genes in mammals and Caenorhabditis elegans. This paper describes a cDNA isolated from zebrafish (...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.251516598
更新日期:2001-12-04 00:00:00
abstract::The photosystem II (PSII) subunit S (PsbS) plays a key role in nonphotochemical quenching, a photoprotective mechanism for dissipation of excess excitation energy in plants. The precise function of PsbS in nonphotochemical quenching is unknown. By reconstituting PsbS together with the major light-harvesting complex of...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1205561110
更新日期:2013-04-02 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
pub_type: 杂志文章
doi:10.1073/pnas.1722531115
更新日期:2018-03-06 00:00:00
abstract::Germ-line mutations of the BRCA2 tumor suppressor gene greatly increase the risk of developing breast and ovarian cancers. Here, we show that wild-type BRCA2, but not a tumor-specific truncated mutant BRCA2, synergizes with the nuclear receptor coactivator p160 GRIP1 to enhance transcriptional activation by androgen r...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1132020100
更新日期:2003-06-10 00:00:00
abstract::It has often been suggested that the frequently observed Watson-Crick base-pair compensatory substitutions in RNA helical structures occur mainly through a slightly deleterious G.U intermediate state. We have scored base substitutions in a set of 82 related Drosophila species for the D1 and D2 variable domains of the ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.22.10032
更新日期:1991-11-15 00:00:00
abstract::We have used expression cloning in Xenopus oocytes to isolate two different cDNAs encoding functional N-methyl-D-aspartate (NMDA) receptor subunits. The two receptors (NMDA-R1A and -R1B) display different pharmacologic properties as a consequence of alternative exon addition within the putative ligand-binding domain. ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.89.18.8552
更新日期:1992-09-15 00:00:00
abstract::Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19, employs two key host proteins to gain entry and replicate within cells, angiotensin-converting enzyme 2 (ACE2) and the cell surface transmembrane protease serine 2 (TMPRSS2). TMPRSS2 was first characterized as an androgen...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.2021450118
更新日期:2020-12-11 00:00:00
abstract::Certain chemical systems which differ greatly in many of their chemical properties may nevertheless exhibit stereochemically isomorphic behavior, i.e., they may be stereochemically correspondent. Two such systems are spirocyclic pentacoordinate molecules and molecules of the type Ar(2)ZX. The consequences of stereoche...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.70.12.3445
更新日期:1973-12-01 00:00:00
abstract::Pokeweed antiviral protein (PAP), a 29-kDa protein isolated from Phytolacca americana, inhibits translation by catalytically removing a specific adenine residue from the large rRNA of the 60S subunit of eukaryotic ribosomes. In addition to its ribosome-inactivating ability, PAP has potent antiviral activity against ma...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.8.3866
更新日期:1997-04-15 00:00:00
abstract::Homeostasis of intravascular volume, Na(+), Cl(-), and K(+) is interdependent and determined by the coordinated activities of structurally diverse mediators in the distal nephron and the distal colon. The behavior of these flux pathways is regulated by the renin-angiotensin-aldosterone system; however, the mechanisms ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0611727104
更新日期:2007-03-06 00:00:00
abstract::The population genetic consequences of nearest-neighbor pollination in an outcrossing plant species were investigated through computer simulations. The genetic system consisted of two alleles at a single locus in a self-incompatible plant that mates by random pollen transfer from a neighboring individual. Beginning wi...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.79.1.203
更新日期:1982-01-01 00:00:00
abstract::Type 2 diabetes is preceded by the development of insulin resistance, in which the action of insulin is impaired, largely in skeletal muscles. Caveolin-3 (Cav3) is a muscle-specific subtype of caveolin, an example of a scaffolding protein found within membranes. Cav is also known as growth signal inhibitor, although i...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0402053101
更新日期:2004-08-24 00:00:00
abstract::We are investigating the feasibility of using the positive-strand RNA virus Sindbis virus and its defective interfering (DI) particles as vectors for introducing foreign genes into cells. In previous work we showed by deletion mapping of a cloned cDNA derived from one of the DI RNAs that only nucleotides at the 3' and...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.84.14.4811
更新日期:1987-07-01 00:00:00
abstract::Many "workers" in north temperate colonies of the eusocial paper wasp Polistes fuscatus disappear within a few days of eclosion. We provide evidence that these females are pursuing an alternative reproductive strategy, i.e., dispersing to overwinter and become nest foundresses the following spring, instead of helping ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.95.23.13737
更新日期:1998-11-10 00:00:00
abstract::The serum thymic factor (FTS) utilized in its synthetic or natural form loses its biological activity in a rosette assay after treatment with a metal ion-chelating agent, Chelex 100. This activity is restored by the addition of Zn salts and, to a lesser extent, certain other metal salts. FTS activation is secondary to...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.79.17.5370
更新日期:1982-09-01 00:00:00
abstract::The signal recognition particle (SRP) is a ribonucleoprotein composed of an Alu domain and an S domain. The S domain contains unique sequence SRP RNA and four SRP proteins: SRP19, SRP54, SRP68, and SRP72. SRP interacts with ribosomes to bring translating membrane and secreted proteins to the endoplasmic reticulum (ER)...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.97.1.55
更新日期:2000-01-04 00:00:00
abstract::Molecular genetic analyses of the young pseudogenes of the immunoglobulin C epsilon genes were carried out to obtain qualitative evidence for the phylogenetic branching pattern of hominoid primates. We found that Old World monkeys had two C epsilon genes, one of which was processed. Among the hominoids examined only t...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.11.3712
更新日期:1985-06-01 00:00:00