Abstract:
:Accumulation of (45)Ca(++) was found to occur in membrane vesicles of E. coli prepared by lysis with a French pressure cell. The uptake occurs by active transport, requiring an energy source. Substrates of the electron transport chain, including D-lactate, reduced phenazine methosulfate, and NADH, stimulated accumulation, but this effect was blocked by the addition of cyanide. ATP could also stimulate accumulation, and this effect was blocked by dicyclohexylcarbodiimide. Uncouplers of oxidative phosphorylation inhibited the accumulation driven by either type of energy source. Accumulation of calcium is rapid, reaching the steady-state plateau within 1 min. Addition of phosphate to the assay buffer results in a prolongation of the reaction, allowing for the time-dependent accumulation of calcium for as long as 30 min. Vesicles prepared by lysis with a French pressure cell exhibit almost no ability to accumulate proline, while vesicles prepared by the method of Kaback transport proline but exhibit little energy-dependent transport of calcium. It is suggested that the accumulation of calcium in these vesicles, which are believed to be inverted, reflects a system that in vivo is responsible for the active extrusion of calcium from the cells.
journal_name
Proc Natl Acad Sci U S Aauthors
Rosen BP,McClees JSdoi
10.1073/pnas.71.12.5042subject
Has Abstractpub_date
1974-12-01 00:00:00pages
5042-6issue
12eissn
0027-8424issn
1091-6490journal_volume
71pub_type
杂志文章abstract::Mouse myeloma cells were pulse-labeled in vitro with (3)H-D-glucosamine and (14)C-L-leucine. Analysis on sucrose gradients revealed incorporation of both isotopes into polyribosomes and release of most of such radioactivity after treatment of labeled cells in vitro with puromycin. A mixing experiment excluded the in v...
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.64.1.381
更新日期:1969-09-01 00:00:00
abstract::The peroxisome biogenesis disorders (PBDs), including Zellweger syndrome (ZS) and neonatal adrenoleukodystrophy (NALD), are autosomal recessive diseases caused by defects in peroxisome assembly, for which at least 10 complementation groups have been reported. We have isolated a human PEX1 cDNA (HsPEX1) by functional c...
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.95.8.4350
更新日期:1998-04-14 00:00:00
abstract::The H2O2-requiring ligninase of the basidiomycete Phanerochaete chrysosporium oxidatively cleaves both lignin and lignin model compounds between C alpha and C beta (C-1 and C-2) of their aliphatic side chains. Previous work has demonstrated a reaction mechanism by which ligninase oxidizes aromatic substrates to their ...
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.83.11.3708
更新日期:1986-06-01 00:00:00
abstract::All cell functions that involve membrane deformation or a change in cell shape (e.g., endocytosis, exocytosis, cell motility, and cytokinesis) are regulated by membrane tension. While molecular contacts between the plasma membrane and the underlying actin cytoskeleton are known to make significant contributions to mem...
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.0901641106
更新日期:2009-07-21 00:00:00
abstract::The pattern of neurodegeneration in Alzheimer's disease (AD) is very distinctive: neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau selectively affect pyramidal neurons of the aging association cortex that interconnect extensively through glutamate synapses on dendritic spines. In contrast, primary se...
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.1322360111
更新日期:2014-04-01 00:00:00
abstract::Amber suppressor tRNA genes were constructed by site-specific mutagenesis of the anticodons of human lysine-inserting tRNA (tRNA(Lys)) and glutamine-inserting tRNA (tRNA(Gln)) genes, and a Xenopus laevis tyrosine-inserting tRNA (tRNA(Tyr)) gene. As previous in vitro studies in prokaryotes have shown that substitution ...
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.84.8.2185
更新日期:1987-04-01 00:00:00
abstract::Among the earliest and most important stages during tumorigenesis is the activation of the angiogenic process, an event that is termed the "switch to the angiogenic phenotype." We have developed an in vivo system that can reliably recapitulate the stages in tumor development that represent this transition. Using this ...
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.97.8.3884
更新日期:2000-04-11 00:00:00
abstract::Twenty years after their discovery, knots in proteins are now quite well understood. They are believed to be functionally advantageous and provide extra stability to protein chains. In this work, we go one step further and search for links-entangled structures, more complex than knots, which consist of several compone...
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.1615862114
更新日期:2017-03-28 00:00:00
abstract::Mucolipidosis type IV is an autosomal recessive lysosomal storage disease of unknown etiology that causes severe neurological and ophthalmological abnormalities. In an attempt to obtain insight into the nature of the metabolic abnormality in this disorder, we prospectively evaluated 15 consecutive patients, aged 2 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.95.3.1207
更新日期:1998-02-03 00:00:00
abstract::Ca(2+) is essential for physiological depolarization-evoked synchronous neurotransmitter release. But, whether Ca(2+) influx or another factor controls release initiation is still under debate. The time course of ACh release is controlled by a presynaptic inhibitory G protein-coupled autoreceptor (GPCR), whose agonist...
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.0708540105
更新日期:2008-03-18 00:00:00
abstract::Helodermin is a vasoactive intestinal peptide-like peptide in the salivary gland venom of the lizard Heloderma suspectum. Helodermin-like immunofluorescence was observed in the parafollicular (C) cells in several mammals and in the C cell homologues of the chicken ultimobranchial gland. Thus, helodermin-like peptides ...
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.86.4.1357
更新日期:1989-02-01 00:00:00
abstract::Nitrogen limitation imposes a major transition in the lifestyle of nondiazotrophic cyanobacteria that is controlled by a complex interplay of regulatory factors involving the pervasive signal processor PII Immediately upon nitrogen limitation, newly fixed carbon is redirected toward glycogen synthesis. How the metabol...
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.2019988118
更新日期:2021-02-09 00:00:00
abstract::Novel organismal structures in metazoans are often undergirded by complex gene regulatory networks; as such, understanding the emergence of new structures through evolution requires reconstructing the series of evolutionary steps leading to these underlying networks. Here, we reconstruct the step-by-step assembly of 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.1012333108
更新日期:2011-03-29 00:00:00
abstract::In bacteria, the first two steps of gene expression-transcription and translation-are spatially and temporally coupled. Uncoupling may lead to the arrest of transcription through RNA polymerase backtracking, which interferes with replication forks, leading to DNA double-stranded breaks and genomic instability. How tra...
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.1919985117
更新日期:2020-04-14 00:00:00
abstract::Fms-like tyrosine kinase 1 (Flt1)/vascular endothelial growth factor (VEGF) receptor 1, a receptor for VEGF-A and placental growth factor, is expressed in the spongiotrophoblast layer that segregates the maternal and fetal vasculature in the mouse placenta. A soluble form of Flt1 (sFlt1) produced in the mouse and huma...
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.2635424100
更新日期:2003-12-23 00:00:00
abstract::Natural antimicrobial peptides (AMPs) provide prototypes for the design of unconventional antimicrobial agents. Existing bulk assays measure AMP activity but do not provide details of the growth-halting mechanism. We use fluorescence microscopy to directly observe the attack of the human antimicrobial peptide LL-37 on...
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.1101130108
更新日期:2011-04-19 00:00:00
abstract::Fas, a member of the tumor necrosis factor receptor family, can induce apoptosis when activated by Fas ligand binding or anti-Fas antibody crosslinking. Genetic studies have shown that a defect in Fas-mediated apoptosis resulted in abnormal development and function of the immune system in mice. A point mutation in 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.92.25.11894
更新日期:1995-12-05 00:00:00
abstract::Recombination is unknown in natural populations of Rivulus marmoratus, a selfing hermaphrodite, and genetic variation is likely due to mutation alone. DNA fingerprinting with an array of microsatellite [e.g., (CT)9] and minisatellite (e.g., the 33.15 core sequence) probes reveals very high clonal diversity within samp...
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.89.22.10643
更新日期:1992-11-15 00:00:00
abstract::Psychostimulant use is an ever-increasing socioeconomic burden, including a dramatic rise during pregnancy. Nevertheless, brain-wide effects of psychostimulant exposure are incompletely understood. Here, we performed Fos-CreERT2-based activity mapping, correlated for pregnant mouse dams and their fetuses with amphetam...
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.1904006116
更新日期:2019-12-17 00:00:00
abstract::Metal-inducible transcription of metallothionein (MT) genes involves the interaction of metal-responsive trans-acting factors with specific promoter DNA sequence elements. In this report, we present a genetic selection using the baker's yeast, Saccharomyces cerevisiae, to clone a gene from Candida glabrata encoding a ...
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.88.14.6112
更新日期:1991-07-15 00:00:00
abstract::In liquids realm, surface tension and capillarity are the key forces driving the formation of the shapes pervading the nature. The steady dew drops appearing on plant leaves and spider webs result from the minimization of the overall surface energy [Zheng Y, et al. (2010) Nature 463:640-643]. Thanks to the surface ten...
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.1110676108
更新日期:2011-09-13 00:00:00
abstract::Near-zero-index (NZI) supercoupling, the transmission of electromagnetic waves inside a waveguide irrespective of its shape, is a counterintuitive wave effect that finds applications in optical interconnects and engineering light-matter interactions. However, there is a limited knowledge on the local properties 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.2008143117
更新日期:2020-09-29 00:00:00
abstract::Previous reconstructions of marine fishing fleets have aggregated data without regard to the artisanal and industrial sectors. Engine power has often been estimated from subsets of the developed world, leading to inflated results. We disaggregated data into three sectors, artisanal (unpowered/powered) and industrial, ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 历史文章,杂志文章
doi:10.1073/pnas.1820344116
更新日期:2019-06-18 00:00:00
abstract::The expression of a number of genes encoding products involved in copper ion uptake in yeast is specifically inhibited by copper ions. We show here that copper metalloregulation occurs through Cu-dependent repression of the transactivation activity of Mac1p. A segment of the yeast transcription factor Mac1p was identi...
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.94.11.5550
更新日期:1997-05-27 00:00:00
abstract::Wnt/beta-catenin signaling controls various cell fates in metazoan development and is misregulated in several cancers and developmental disorders. Binding of a Wnt ligand to its transmembrane coreceptors inhibits phosphorylation and degradation of the transcriptional coactivator beta-catenin, which then translocates 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.0803025105
更新日期:2008-06-10 00:00:00
abstract::Nerve growth factor has been quantified by both bioassay and radial immunodiffusion in mouse saliva elicited by several secretagogues. The concentrations by bioassay of nerve growth factor in both epinephrine- and norepinephrine-induced saliva (3400 and 900 mug/ml, respectively) are higher than reported in any other s...
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.73.11.4210
更新日期:1976-11-01 00:00:00
abstract::Superoxide dismutases (SODs; superoxide: superoxide oxidoreductase, EC 1.15.1.1) play a key role in protection against oxygen radicals, and SOD gene expression is highly induced during environmental stress. To determine the conditions of SOD induction, the promoter of the cytosolic copper/zinc SOD (Cu/ZnSODcyt) gene w...
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.90.7.3108
更新日期:1993-04-01 00:00:00
abstract::Therapy-related acute myeloid leukemias (t-AML) with translocations of the MLL gene are associated with the use of topoisomerase II inhibitors. We established the emergence of the malignant clone in a child who developed t-AML with a t(11;19) (q23;p13.3) during treatment for acute lymphoblastic leukemia (ALL). The MLL...
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.181199898
更新日期:2001-08-28 00:00:00
abstract::Junctions that mediate excitation-contraction (e-c) coupling are formed between the sarcoplasmic reticulum (SR) and either the surface membrane or the transverse (T) tubules in normal skeletal muscle. Two structural components of the junctions, the feet of the SR and the tetrads of T tubules, have been identified resp...
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.92.8.3381
更新日期:1995-04-11 00:00:00
abstract::Fast-atom bombardment mass spectrometry was used to follow the time course of disulfide bond formation during in vitro refolding of recombinant human macrophage-colony-stimulating factor. The content of iodoacetamide-alkylated half-cystines in proteolytic peptides of trapped refolding intermediates collected at 0, 6, ...
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.91.13.5868
更新日期:1994-06-21 00:00:00