Abstract:
:In a medium without Na+, gamma-aminobutyric acid (GABA) binds at 0 degrees to freshly prepared crude synaptic membranes from rat cerebral cortex with an apparent dissociation constant of 218 nM. An endogenous inhibitor of the Na+-independent GABA binding was removed from these membranes by freezing and thawing and by repeated washing with Tris citrate buffer (50 mM, pH 7.1) containing 0.01% Triton X-100. As a result, the crude synaptic membranes bind GABA at 0 degrees with two dissociation constants, 20 nM and 111 nM. The endogenous inhibitor is a thermostable (95 degrees for 15 min) acidic protein of approximately 1.5 X 10(4) daltons. It was purified (about 500-fold) with a series of procedures including gel chromatography on Sephadex G-100 and ion exchange chromatography on Dowex 50W-X8 (H+). Recombination of the purified endogenous inhibitor with crude synaptic membrane preparations deprived of the endogenous inhibitor showed that the purified inhibitor blocked noncompetitively the sites for high-affinity GABA binding. A role of this endogenous regulator in the functional of GABA-ergic synapses is discussed.
journal_name
Proc Natl Acad Sci U S Aauthors
Toffano G,Guidotti A,Costa Edoi
10.1073/pnas.75.8.4024subject
Has Abstractpub_date
1978-08-01 00:00:00pages
4024-8issue
8eissn
0027-8424issn
1091-6490journal_volume
75pub_type
杂志文章abstract::Cytoplasmic RNA extracted from human tissue culture cells infected with adenovirus type 2 was used to program protein synthesis in a cell-free system derived from mammalian cells. Analysis of the protein product by polyacrylamide gel electrophoresis revealed ten adenovirus-specific polypeptides. Five of these were fur...
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.71.7.2756
更新日期:1974-07-01 00:00:00
abstract::Microorganisms modify rates and mechanisms of chemical and physical weathering and clay growth, thus playing fundamental roles in soil and sediment formation. Because processes in soils are inherently complex and difficult to study, we employ a model based on the lichen-mineral system to identify the fundamental inter...
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.96.7.3404
更新日期:1999-03-30 00:00:00
abstract::The aryl hydrocarbon receptor nuclear translocator (ARNT) is a basic helix-loop-helix Period/ARNT/Single-minded (bHLH-PAS) protein that controls various biological pathways as part of dimeric transcriptional regulator complexes with other bHLH-PAS proteins. The two PAS domains within ARNT, PAS-A and PAS-B, are essenti...
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.0808270106
更新日期:2009-02-24 00:00:00
abstract::The rationale for genome-wide association study (GWAS) results is sequence variation in cis-regulatory elements (CREs) modulating a target gene's expression as the major cause of trait variation. To understand the complete molecular landscape of one of these GWAS loci, we performed in vitro reporter screens in cardiom...
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.1808734116
更新日期:2019-05-28 00:00:00
abstract::Silicate melts at the top of the transition zone and the core-mantle boundary have significant influences on the dynamics and properties of Earth's interior. MgSiO3-rich silicate melts were among the primary components of the magma ocean and thus played essential roles in the chemical differentiation of the early Eart...
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.0802667105
更新日期:2008-06-10 00:00:00
abstract::The precipitation and assembly of calcium carbonate skeletons by stony corals is a precisely controlled process regulated by the secretion of an ECM. Recently, it has been reported that the proteome of the skeletal organic matrix (SOM) contains a group of coral acid-rich proteins as well as an assemblage of adhesion 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.1408621111
更新日期:2014-09-02 00:00:00
abstract::Seed germination is regulated by endogenous hormonal cues and external environmental stimuli such as water, low temperature, and light. After germination, the young seedling must rapidly establish its root system and the photoautotrophic capability appropriate to its surrounding environment. Light and the phytohormone...
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.0710778105
更新日期:2008-03-18 00:00:00
abstract::Cytokines such as interleukin 4 (IL-4) play a key role in the regulation of immune responses, but little is known about how their multiple activities are regulated in vivo. In this report, we demonstrated that an IL-4-binding protein (IL-4BP) is constitutively present in the biological fluids of mice (serum, ascites, ...
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.87.11.4202
更新日期:1990-06-01 00:00:00
abstract::The possible role of guanosine 5'-triphosphate,3'-diphosphate (pppGpp) in protein synthesis by Escherichia coli ribosomes and protein factors was examined. Although pppGpp could effectively substitute for GTP in reactions catalyzed by initiation factor 2 (ribosomal binding of fMet-tRNA and formation of N-formylmethion...
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.70.11.3250
更新日期:1973-11-01 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::The adenovirus (Ad) early region 3 (E3) genes code for at least four proteins that inhibit the host immune responses mediated by cytotoxic T lymphocytes and tumor necrosis factor alpha. To evaluate the potential use of these immunoregulatory viral functions in facilitating allogeneic cell transplantation, the Ad E3 ge...
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.92.15.6947
更新日期:1995-07-18 00:00:00
abstract::An understanding of the division of labor in different societies, and especially how it evolved in the human species, is fundamental to most analyses of social, political, and economic systems. The ability to reconstruct how labor was organized, however, especially in ancient societies that left behind few material re...
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.1901367116
更新日期:2019-06-18 00:00:00
abstract::Cellular membranes are a heterogeneous mix of lipids, proteins and small molecules. Special groupings enriched in saturated lipids and cholesterol form liquid-ordered domains, known as "lipid rafts," thought to serve as platforms for signaling, trafficking and material transport throughout the secretory pathway. Quest...
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.0903825106
更新日期:2009-08-11 00:00:00
abstract::Pentamidine, diminazene aceturate (Berenil), isometamidium chloride (Samorin), and ethidium bromide, which are important antitrypanosomal drugs, promote linearization of Trypanosoma equiperdum minicircle DNA (the principal component of kinetoplast DNA, the mitochondrial DNA in these parasites). This effect occurs at 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.87.3.950
更新日期:1990-02-01 00:00:00
abstract::L-Asparaginase (EC 3.5.1.1) inhibited respiration in sensitive, but not resistant, lines of murine lymphoma 6C3HED. Glucose, in these tumor lines, was principally converted to lactate, and very little was oxidized in the citric acid cycle or hexose monophosphate shunt. The cells derived 70-80% of their respiratory CO(...
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.71.10.3993
更新日期:1974-10-01 00:00:00
abstract::We have analyzed the level of intraindividual sequence variability (heteroplasmy) of mtDNA in human brain by denaturing gradient gel electrophoresis and sequencing. Single base substitutions, as well as insertions or deletions of single bases, were numerous in the noncoding control region (D-loop), and 35-45% of the m...
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.93.22.12382
更新日期:1996-10-29 00:00:00
abstract::Synthesis of normal human hemoglobin A, alpha 2 beta 2, is based upon balanced expression of genes in the alpha-globin gene cluster on chromosome 16 and the beta-globin gene cluster on chromosome 11. Full levels of erythroid-specific activation of the beta-globin cluster depend on sequences located at a considerable 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.87.23.9431
更新日期:1990-12-01 00:00:00
abstract::A new common cell-surface antigen associated with murine and feline C-type RNA leukemia viruses was demonstrated by the use of rabbit antiserum against feline leukemia virus and the indirect membrane immunofluorescence test. Common cell-surface antigen was found in all leukemias of all strains of mice tested, in norma...
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.70.6.1878
更新日期:1973-06-01 00:00:00
abstract::Antigen-specific activation of T lymphocytes, via stimulation of the T-cell antigen receptor (TCR) complex, is marked by a rapid and sustained increase in the concentration of cytoplasmic free Ca2+ ([Ca2+]i). It has been suggested that the second messenger inositol 1,4,5-trisphosphate (IP3) produced after TCR stimulat...
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.92.13.6007
更新日期:1995-06-20 00:00:00
abstract::Both mammals and birds use the interaural time difference (ITD) for localization of sound in the horizontal plane. They may localize either real or phantom sound sources, when the signal consists of a narrow frequency band. This ambiguity does not occur with broadband signals. A plot of impulse rates or amplitude of e...
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.97.22.11787
更新日期:2000-10-24 00:00:00
abstract::We study the dynamic network of e-mail traffic and find that it develops self-organized coherent structures similar to those appearing in many nonlinear dynamic systems. Such structures are uncovered by a general information theoretic approach to dynamic networks based on the analysis of synchronization among trios 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.0405728101
更新日期:2004-10-05 00:00:00
abstract::The chromatin core particle DNA conformation deduced in broad outline by Finch et al. [Finch, J. T., Lutter, L. C., Rhodes, D., Brown, R. S., Rushton, B., Levitt, M. & Klug, A. (1977) Nature 269, 29-36] can be described in detail using other available experimental results. Histone binding sites compatible with the 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.75.8.3649
更新日期:1978-08-01 00:00:00
abstract::Early B cell factor (EBF)1 is essential for B lineage specification. Previously, we demonstrated the synergistic activation of Cd79a (mb-1) genes by EBF1 and its functional partner, RUNX1. Here, we identified consequences of Ebf1 haploinsufficiency together with haploinsufficiency of Runx1 genes in mice. Although 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.1003525107
更新日期:2010-04-27 00:00:00
abstract::Double-positive (DP) thymocytes respond to intrathymic T-cell receptor (TCR) signals by undergoing positive selection and lineage differentiation into single-positive (SP) mature cells. Concomitant with these well-characterized events is the acquisition of a mature T-cell gene expression program characterized by the 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.1617669114
更新日期:2017-01-03 00:00:00
abstract::Many synthetic or natural fibers are produced via the transformation of a liquid solution into a solid filament, which allows the wet processing of high molecular weight polymers, proteins, or inorganic particles. Synthetic wet-spun fibers are used in our everyday life from clothing to composite reinforcement applicat...
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.1003302107
更新日期:2010-10-26 00:00:00
abstract::In the retina, dopamine plays a central role in neural adaptation to light. Progress in the study of dopaminergic amacrine (DA) cells has been limited because they are very few (450 in each mouse retina, 0.005% of retinal neurons). Here, we applied transgenic technology, single-cell global mRNA amplification, and cDNA...
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.0400913101
更新日期:2004-04-06 00:00:00
abstract::Isochorismate synthase (ICS) converts chorismate to isochorismate for the biosynthesis of phylloquinone, an essential cofactor for photosynthetic electron transport. ICS is also required for salicylic acid (SA) synthesis during Arabidopsis defense. In several other species, including Populus, SA is derived primarily f...
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.0906869106
更新日期:2009-12-22 00:00:00
abstract::A key component of scientific communication is sufficient information for other researchers in the field to reproduce published findings. For computational and data-enabled research, this has often been interpreted to mean making available the raw data from which results were generated, the computer code that generate...
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.1708290115
更新日期:2018-03-13 00:00:00
abstract::The mammalian form of the protozoan parasite Leishmania mexicana contains high activity of a cysteine proteinase (LmCPb) encoded on a tandem array of 19 genes (lmcpb). Homozygous null mutants for lmcpb have been produced by targeted gene disruption. All life-cycle stages of the mutant can be cultured in vitro, demonst...
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.93.12.6008
更新日期:1996-06-11 00:00:00
abstract::Hitherto it has not been possible to obtain spore and stalk cell differentiation of the cellular slime molds in submerged cultures. It is shown here that cells, when placed in roller tubes under an atmosphere of oxygen, will form clumps and differentiate in 48-72 hr into mature spores and stalk cells. Although differe...
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.74.1.268
更新日期:1977-01-01 00:00:00