Abstract:
:The pH gradient (delta pH) across the membrane of bovine neurohypophysial granules was estimated by using the [14C]methylamine partition technique. The granule membrane showed high permeability to sugars such as sucrose or sorbitol and to cations. Granules suspended in sucrose medium showed an acidic internal delta pH that decreased with external pH from 1.0 pH unit at pH 7.5 to 0 at pH 4.5. High ionic strength of the external medium destroyed the delta pH, indicating that it originated from a Donnan equilibrium. In a medium constituted to simulate cytoplasm, the delta pH was approximately 0.5 pH unit. Aged neurosecretory granules were more acidic inside than were newly formed granules. The results are discussed in relationship to the nature and the duration of maturation and degradation process of the granule matrix.
journal_name
Proc Natl Acad Sci U S Aauthors
Scherman D,Nordmann JJdoi
10.1073/pnas.79.2.476subject
Has Abstractpub_date
1982-01-01 00:00:00pages
476-9issue
2eissn
0027-8424issn
1091-6490journal_volume
79pub_type
杂志文章abstract::Antagonists of growth hormone-releasing hormone (GH-RH) inhibit the growth of various tumors through mechanisms that involve the suppression of the insulin-like growth factor I and/or insulin-like growth factor II levels or secretion. In the present study, we tested the hypothesis that the tumor inhibition is associat...
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.96.1.226
更新日期:1999-01-05 00:00:00
abstract::Intracellular Ca(2+) release in many types of cells is mediated by ryanodine receptor Ca(2+) release channels (RyRCs) that are assembled into two-dimensional paracrystalline arrays in the endoplasmic/sarcoplasmic reticulum. However, the in situ operating mechanism of the RyRC array is unknown. Here, we found that 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.0306157101
更新日期:2004-03-16 00:00:00
abstract::The tumor suppressor Smad4/Dpc4 is a transcription activator that binds specific DNA sequences and whose nuclear localization is induced after exposure to type beta transforming growth factor-like cytokines. We explored an inducible system in which Smad4 protein is activated by translocation to the nucleus when cell l...
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.96.4.1427
更新日期:1999-02-16 00:00:00
abstract::Transfection of cells with the H-2Kk gene lacking the transmembrane and cytoplasmic segments resulted in secretion of the H-2Kk protein, as determined by immunoprecipitation with monoclonal anti-H-2Kk antibodies. Transgenic (H-2b X H-2d)F1 mice were established carrying integrated copies of the modified H-2Kk gene. Ex...
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.85.7.2269
更新日期:1988-04-01 00:00:00
abstract::Saccharomyces cerevisiae strains harboring a nonreciprocal, bridge-induced translocation (BIT) between chromosomes VIII and XV exhibited an abnormal phenotype comprising elongated buds and multibudded, unevenly nucleated pseudohyphae. In these cells, we found evidence of molecular effects elicited by the translocation...
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.0800464105
更新日期:2008-07-15 00:00:00
abstract::These studies sought to determine if neurons in the estrogen receptor-alpha knockout (ERalphaKO) mouse brain concentrated 16alpha-[125I]iodo-11beta-methoxy-17beta-estradiol (125I-estrogen), and if so, whether estrogen binding augmented the expression of progesterone receptor (PR) mRNA. Mice were injected with 125I-est...
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.94.20.11008
更新日期:1997-09-30 00:00:00
abstract::In organisms from insects to vertebrates, Toll-like receptors (TLRs) are primary pathogen detectors that activate downstream pathways, specifically those that direct expression of innate immune effector genes. TLRs also have roles in development in many species. The sea anemone Nematostella vectensis is a useful cnida...
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.1711530114
更新日期:2017-11-21 00:00:00
abstract::In aqueous solution, aldehydes, and to a lesser extent ketones, hydrate to form geminal diols. We investigate the hydration of methylglyoxal (MG) in the gas phase, a process not previously considered to occur in water-restricted environments. In this study, we spectroscopically identified methylglyoxal diol (MGD) 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.0912121107
更新日期:2010-04-13 00:00:00
abstract::Cold-water conditions have excluded durophagous (skeleton-breaking) predators from the Antarctic seafloor for millions of years. Rapidly warming seas off the western Antarctic Peninsula could now facilitate their return to the continental shelf, with profound consequences for the endemic fauna. Among the likely first ...
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.1513962112
更新日期:2015-10-20 00:00:00
abstract::Rotaviruses are the single most common cause of fatal and severe childhood diarrheal illness worldwide (>125 million cases annually). Rotavirus shares structural and functional features with many viruses, such as the presence of segmented double-stranded RNA genomes selectively and tightly packed with a conserved numb...
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.1220345110
更新日期:2013-07-16 00:00:00
abstract::A method using PCR amplification and primer extension with fluorescent oligonucleotides was developed to analyze T-cell repertoires. The sizes of the hypervariable CDR3-like regions of the murine T-cell antigen receptor beta chains were measured for all possible V beta-J beta combinations. This analysis shows that bet...
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.90.9.4319
更新日期:1993-05-01 00:00:00
abstract::The voltage-gated proton channel Hv1 plays a critical role in the fast proton translocation that underlies a wide range of physiological functions, including the phagocytic respiratory burst, sperm motility, apoptosis, and metastatic cancer. Both voltage activation and proton conduction are carried out by a voltage-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.1515043112
更新日期:2015-11-03 00:00:00
abstract::In pulmonary arterial hypertension (PAH), antiapoptotic, proliferative, and inflammatory diatheses converge to create an obstructive vasculopathy. A selective down-regulation of the Kv channel Kv1.5 has been described in human and animal PAH. The resultant increase in intracellular free Ca(2+) ([Ca(2+)](i)) and K(+) (...
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.0610467104
更新日期:2007-07-03 00:00:00
abstract::The use of computers to simulate the functions of complex biological macromolecules is essential to achieve a microscopic description of biological processes and to model and interpret experimental data. Here we apply theoretical computational approaches to investigate the fidelity of T7 DNA polymerase, divided into d...
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.0408173102
更新日期:2005-05-10 00:00:00
abstract::Heteroduplex molecules of pneumococcal DNA, prepared by cross-annealing resolved complementary strands, have been used as donors in transformation. A number of pairs of genetic markers are situated exclusively in the trans configuration in these heteroduplexes. Insertion of two markers from trans configuration into op...
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.69.2.466
更新日期:1972-02-01 00:00:00
abstract::Mixed synthetic oligonucleotides encoding sequences conserved among tyrosine-specific protein kinases were used to probe the genome of the budding yeast Saccharomyces cerevisiae. Two genes with homology to protein kinases were isolated and characterized by DNA sequence analysis. These genes, designated KIN1 and KIN2, ...
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.84.17.6035
更新日期:1987-09-01 00:00:00
abstract::Mutations in the DAX-1 [dosage-sensitive sex reversal-adrenal hypoplasia congenita (AHC) critical region on the X chromosome; NR0B1] gene cause X-linked AHC associated with hypogonadotropic hypogonadism. DAX-1 encodes an unusual orphan member of the nuclear hormone receptor superfamily, acting as a transcriptional rep...
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.122044099
更新日期:2002-06-11 00:00:00
abstract::An array of photoreceptors including cryptochromes, phototropin, and phytochromes regulates various light responses in plants. Among these photoreceptors, phytochromes perceive red and far-red light by switching between two interconvertible spectral forms (Pr and Pfr). The Pfr form promotes light responses partly by d...
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.1109683109
更新日期:2012-01-24 00:00:00
abstract::Sonic hedgehog (Shh) plays an integral role in both the anterior-posterior (A-P) patterning and expansion of developing vertebrate limbs through a feedback loop involving Fgfs, Bmps, and Gremlin. In bat limbs A-P patterning and the size of the digital field are unique. The posterior digits of the forelimb are elongate...
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.0805308105
更新日期:2008-11-04 00:00:00
abstract::Apis mellifera originated in Africa and extended its range into Eurasia in two or more ancient expansions. In 1956, honey bees of African origin were introduced into South America, their descendents admixing with previously introduced European bees, giving rise to the highly invasive and economically devastating "Afri...
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.0800107105
更新日期:2008-03-04 00:00:00
abstract::Reactive oxygen species, the by-products of oxidative energy metabolism, are considered a main proximate cause of aging. Accordingly, overexpression of the enzyme Cu-Zn superoxide dismutase 1 (SOD1) can lengthen lifespan of Drosophila melanogaster in the laboratory. However, the role of SOD1 as a main determinant of l...
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.0400222101
更新日期:2004-03-09 00:00:00
abstract::cDNA libraries were constructed from pathogenic (HM-1:IMSS) and nonpathogenic (SAW 1734) isolates of Entamoeba histolytica. A cDNA clone (cEH-P1) specific for pathogenic amoebae was identified by screening with a pool of sera from patients with invasive amoebiasis that had been absorbed with nonpathogenic amoebae. Thi...
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.86.13.5118
更新日期:1989-07-01 00:00:00
abstract::Excessive activation of calmodulin kinase II (CaMKII) causes arrhythmias and heart failure, but the cellular mechanisms for CaMKII-targeted proteins causing disordered cell membrane excitability and myocardial dysfunction remain uncertain. Failing human cardiomyocytes exhibit increased CaMKII and voltage-gated Ca(2+) ...
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.0913760107
更新日期:2010-03-16 00:00:00
abstract::The auditory cortex is critical for perceiving a sound's location. However, there is no topographic representation of acoustic space, and individual auditory cortical neurons are often broadly tuned to stimulus location. It thus remains unclear how acoustic space is represented in the mammalian cerebral cortex and how...
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.0901023106
更新日期:2009-04-07 00:00:00
abstract::We have previously described an antigen-specific I-Ad-restricted T-cell hybridoma, A1.1, that constitutively releases an antigen-specific immunoregulatory activity into supernatants. Using retrovirally mediated gene transfer, we have found that transfer of the T-cell receptor alpha chain (TCR alpha) gene from A1.1 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.88.19.8475
更新日期:1991-10-01 00:00:00
abstract::Site-directed mutagenesis of selected residues of mammalian protein phosphatase 1 (PP-1) has been carried out to further define the mechanism of catalysis, activation by divalent cations, and inhibition by toxins and inhibitory proteins. Mutation of active site residues predicted to bind metals (N124D and H248N) resul...
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.94.8.3530
更新日期:1997-04-15 00:00:00
abstract::Ionotropic alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors (iGluRs) mediate the majority of excitatory synaptic transmission in the CNS and are essential for the induction and maintenance of long-term potentiation and long-term depression, two cellular models of learning and memory. We 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.0708699104
更新日期:2007-11-13 00:00:00
abstract::Cell membrane proteins synthesized after infection of Escherichia coli B with wild-type phage T4 and rIIA mutants were analyzed by dodecyl sulfate-polyacrylamide gel electrophoresis. A protein with an approximate molecular weight of 74,000 is present in membranes isolated from T4r(+)-infected cells, but is not found 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.70.5.1468
更新日期:1973-05-01 00:00:00
abstract::We explored the detection of genome-wide hypomethylation in plasma using shotgun massively parallel bisulfite sequencing as a marker for cancer. Tumor-associated copy number aberrations (CNAs) could also be observed from the bisulfite DNA sequencing data. Hypomethylation and CNAs were detected in the plasma DNA of pat...
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.1313995110
更新日期:2013-11-19 00:00:00
abstract::Brefeldin A, a fungal metabolite that inhibits membrane transport, induces the mono(ADP-ribosyl)ation of two cytosolic proteins of 38 and 50 kDa as judged by SDS/PAGE. The 38-kDa substrate has been previously identified as glyceraldehyde-3-phosphate dehydrogenase (GAPDH). We report that the 50-kDa BFA-induced ADP-ribo...
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.92.15.7065
更新日期:1995-07-18 00:00:00