Abstract:
:Real-time visualization of intracellular calcium concentration ([Ca2+]i) changes in mammalian Purkinje cells in vitro, utilizing the dye Fura-2, indicates that calcium action potentials are generated in the dendritic tree and follow a particular activation sequence. During spontaneous oscillations or after direct current injection, dendritic spikes are initiated as slow and graded plateau potentials at the level of the tertiary or spiny branchlets of the dendrite. As the plateau potentials become sufficiently high to reach the firing threshold for full dendritic spike generation, calcium entry is observed at the more proximal branches of the dendritic tree. These action potentials are then conducted orthodromically toward the soma and may invade other branches in the arbor antidromically. Simultaneous recording of the intracellular electrical activity and the Fura-2 fluorescent signal indicates that the intracellular calcium transients are accompanied by a very rapid increase in intracellular calcium concentration. This increase in [Ca2+]i exhibits an almost equally fast return to baseline after the termination of the action potential, indicating the presence of very efficient calcium sequestering and extruding mechanisms in the dendrites. Iontophoretic application of glutamate at the dendritic level provided a further demonstration of the spatial separation of plateau potentials from dendritic spikes and gives further insights into the details of dendritic integration in this neuron.
journal_name
Proc Natl Acad Sci U S Aauthors
Sugimori M,Llinás RRdoi
10.1073/pnas.87.13.5084subject
Has Abstractpub_date
1990-07-01 00:00:00pages
5084-8issue
13eissn
0027-8424issn
1091-6490journal_volume
87pub_type
杂志文章abstract::The mammalian protein ZnT3 resides on synaptic vesicle membranes of zinc-containing neurons, suggesting its possible role in vesicular zinc transport. We show here that histochemically reactive zinc, corresponding to the zinc found within synaptic vesicles, was undetectable in the brains of mice with targeted disrupti...
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.96.4.1716
更新日期:1999-02-16 00:00:00
abstract::The gluconate (gnt) operon of Bacillus subtilis consists of four gnt genes; the second and third genes code for gluconate kinase (gluconokinase, EC 2.7.1.12) and gluconate permease, respectively. A fragment carrying the promoter of this operon (gnt promoter) and the first gene (gntR) was subcloned into a promoter prob...
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.84.13.4524
更新日期:1987-07-01 00:00:00
abstract::ChIP coupled with microarray provides a powerful tool to determine in vivo binding profiling of transcription factors to deduce regulatory circuitries in mammalian cells. Aiming at improving the specificity and sensitivity of such analysis, we developed a new technology called ChIP-DSL using the DNA selection and liga...
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.0700715104
更新日期:2007-03-20 00:00:00
abstract::Antibodies from three different lines of monoclonal hybridomas crossreact with both the beta subunit of spectrin and the 90-kDa peptide present in highly purified preparations of the heme-controlled eIF-2 alpha (initiation factor 2 alpha-subunit) kinase from rabbit reticulocytes. Antibodies from two of the three lines...
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.82.16.5332
更新日期:1985-08-01 00:00:00
abstract::To explore protein space from a global perspective, we consider 9,710 SCOP (Structural Classification of Proteins) domains with up to 70% sequence identity and present all similarities among them as networks: In the "domain network," nodes represent domains, and edges connect domains that share "motifs," i.e., signifi...
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.1403395111
更新日期:2014-08-12 00:00:00
abstract::Glucocorticoids play an important biphasic role in modulating neural plasticity; low doses enhance neural plasticity and spatial memory behavior, whereas chronic, higher doses produce inhibition. We found that 3 independent measures of mitochondrial function-mitochondrial oxidation, membrane potential, and mitochondri...
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.0812671106
更新日期:2009-03-03 00:00:00
abstract::Although nanoparticle-protein conjugates have been synthesized for numerous applications, bioconjugation remains a challenge, often resulting in denaturation or loss of protein function. This is partly because the protein-nanoparticle interface is poorly understood, which impedes the use of nanoparticles in nanomedici...
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.0807299106
更新日期:2009-03-17 00:00:00
abstract::Gap junctions are specialized membrane regions that seem to mediate intercellular communication. They appear to contain closely packed arrays of equally sized particles all of which, upon freeze-cleaving, remain attached to one membrane leaflet and not to the other. One gap junction cleavage face, therefore, always 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.69.5.1318
更新日期:1972-05-01 00:00:00
abstract::We have determined the nucleotide sequence of the dihydrofolate reductase-thymidylate synthetase (DHFR-TS) gene of the protozoan parasite Leishmania major (dihydrofolate reductase, EC 1.5.1.3 and thymidylate synthase, EC 2.1.1.45). The DHFR-TS protein is encoded by a single 1560-base-pair open reading frame within gen...
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.83.8.2584
更新日期:1986-04-01 00:00:00
abstract::The fluorescence of the supposedly buried tryptophan in ribonuclease T1 has been found to be collisionally quenched by acrylamide with a rate constant of 3 X 10(8) M--1 sec--1. Only a slight decrease in the quenching rate is observed upon a 5-fold increase in the viscosity of the solution. For this to be the case, 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.72.9.3290
更新日期:1975-09-01 00:00:00
abstract::During the last 15 years several laboratories have attempted to generate rabbit monoclonal antibodies, mainly because rabbits recognize antigens and epitopes that are not immunogenic in mice or rats, two species from which monoclonal antibodies are usually generated. Monoclonal antibodies from rabbits could not be gen...
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.92.20.9348
更新日期:1995-09-26 00:00:00
abstract::The Arabidopsis thaliana AtHKT1 protein, a Na(+)/K(+) transporter, is capable of mediating inward Na(+) currents in Xenopus laevis oocytes and K(+) uptake in Escherichia coli. HKT1 proteins are members of a superfamily of K(+) transporters. These proteins have been proposed to contain eight transmembrane segments 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.101556598
更新日期:2001-05-22 00:00:00
abstract::Hybridomas producing human monoclonal IgM antibodies (mAbs) against bacterial lipopolysaccharide (LPS) were generated by fusion of B lymphocytes from sensitized human spleen with heteromyeloma cells. The splenocytes were from patients undergoing splenectomy during staging for Hodgkin disease after vaccination with 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.82.6.1790
更新日期:1985-03-01 00:00:00
abstract::During heat shock, structural changes in proteins and membranes may lead to cell death. While GroE and other chaperone proteins are involved in the prevention of stress-induced protein aggregation and in the recovery of protein structures, a mechanism for short-term membrane stabilization during stress remains to be 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.94.6.2192
更新日期:1997-03-18 00:00:00
abstract::LINEs are transposable elements found in various eukaryotes such as plants, protists, insects, and mammals. Their transposition is usually difficult to study, particularly in humans, where some diseases have been shown to result from LINE insertion mutations. This is due to the fact that most copies of any particular ...
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.88.11.4907
更新日期:1991-06-01 00:00:00
abstract::Alzheimer's disease is a neurodegenerative disorder characterized by the accumulation of amyloid plaques in the brain. This amyloid primarily contains amyloid-beta (Abeta), a 39- to 43-aa peptide derived from the proteolytic cleavage of the endogenous amyloid precursor protein. The 42-residue-length Abeta peptide (Abe...
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.0901085106
更新日期:2009-03-24 00:00:00
abstract::The TATA box-binding activity of transcription factor IID (TFIID) is autoinhibited by the N-terminal domain of the Drosophila TATA box-binding protein- (TBP) associated factor 230/yeast TBP-associated factor 145 subunit, which binds to the TATA box-binding domain of TBP by mimicking the TATA box structure. Here, we pr...
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.120074297
更新日期:2000-06-20 00:00:00
abstract::The single-pass transmembrane domains (TMDs) of the syndecan family of cell surface adhesion molecules have been implicated in functional protein-protein interactions. Although each paralog contains a conserved GxxxG dimerization motif, we show here that the syndecan-1 TMD dimerizes weakly, the syndecan-3 and syndecan...
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.0708909105
更新日期:2007-12-26 00:00:00
abstract::Fluorescence of quinacrine in the presence of different polynucleotides was studied to attempt to identify the specific nucleotides responsible for the fluorescence of stained chromosome preparations. A marked enhancement of fluorescence was seen in the presence of bihelical polynucleotides, such as poly(dA-dT), poly(...
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.69.3.629
更新日期:1972-03-01 00:00:00
abstract::We have screened about 1.4 million colonies of Escherichia coli K-12 for their ability to grow on nutrient agar at 30 degrees and 41 degrees. Among the 2266 temperature-sensitive mutants found, 110 were defective in DNA synthesis but not in protein synthesis at 41 degrees. Three of these dna mutations mapped at two pr...
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.74.8.3485
更新日期:1977-08-01 00:00:00
abstract::The Toll/IL-1 receptor (TIR) domains are crucial signaling modules during innate immune responses involving the Toll-like receptors (TLRs) and IL-1 receptor (IL-1R). Myeloid differential factor 88 (MyD88) is a central TIR domain-containing adapter molecule responsible for nearly all TLR-mediated signaling and is targe...
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.1215770110
更新日期:2013-04-23 00:00:00
abstract::It has recently been recognized that human serum contains a protein that specifically binds human growth hormone (hGH). This protein has the same restricted specificity for hGH as the membrane-bound GH receptor. To determine whether the GH-binding protein is a derivative of, or otherwise related to, the GH receptor, 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.84.13.4636
更新日期:1987-07-01 00:00:00
abstract::Transcription initiation is a dynamic process in which RNA polymerase (RNAP) and promoter DNA act as partners, changing in response to one another, to produce a polymerase/promoter open complex (RPo) competent for transcription. In Escherichia coli RNAP, region 1.1, the N-terminal 100 residues of sigma(70), is thought...
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.0808133106
更新日期:2009-01-20 00:00:00
abstract::Split GFPs have been widely applied for monitoring protein-protein interactions by expressing GFPs as two or more constituent parts linked to separate proteins that only fluoresce on complementing with one another. Although this complementation is typically irreversible, it has been shown previously that light acceler...
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.1618087114
更新日期:2017-03-14 00:00:00
abstract::Endosymbiotic acquisition of bacteria by a protist, with subsequent evolution of the bacteria into mitochondria and plastids, had a transformative impact on eukaryotic biology. Reconstructing events that created a stable association between endosymbiont and host during the process of organellogenesis--including establ...
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.1118800109
更新日期:2012-04-03 00:00:00
abstract::Cyclooxygenase (COX)-2, a rate-limiting enzyme of prostaglandin (PG) production, is overexpressed in colorectal adenomas and adenocarcinomas, and its inhibition by nonsteroidal antiinflammatory drugs protects against colorectal cancer. Mechanisms of cancer promotion by COX-2 are not fully understood, but signaling thr...
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.1533221100
更新日期:2003-07-22 00:00:00
abstract::Lantibiotics are ribosomally synthesized, posttranslationally modified peptide antibiotics. The biosynthetic gene cluster for microbisporicin, a potent lantibiotic produced by the actinomycete Microbispora corallina containing chlorinated tryptophan and dihydroxyproline residues, was identified by genome scanning 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.1008285107
更新日期:2010-07-27 00:00:00
abstract::Ribonuclease H (EC 3.1.4.34) has been used to remove selectively much of the 3'-terminal poly(adenylic acid) [poly(A)] from poliovirus RNA by treating the RNA with the enzyme in the presence of poly(dT). Over 80% of the poly(A) could be removed and the residuum was found as oligo(A) stretches attached to many or all o...
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.71.8.2983
更新日期:1974-08-01 00:00:00
abstract::We have developed an in vitro transcription system that uses nuclei isolated from Lemna gibba G-3. The in vitro transcripts include sequences homologous to hybridization probes for the small subunit of ribulose-1,5-bisphosphate carboxylase [3-phospho-D-glycerate carboxy-lyase (dimerizing), EC 4.1.1.39], the light-harv...
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.81.4.1112
更新日期:1984-02-01 00:00:00
abstract::Cultural and linguistic groups are often expected to represent genetic populations. In this article, we tested the hypothesis that the hierarchical classification of languages proposed by J. Greenberg [(1987) Language in the Americas (Stanford Univ. Press, Stanford, CA)] also represents the genetic structure of Native...
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.0409301102
更新日期:2005-02-01 00:00:00