Abstract:
:Leaflets of Samanea saman open and close rhythmically, driven by an endogenous circadian clock. Light has a rapid, direct effect on the movements and also rephases the rhythm. We investigated whether light signals might be mediated by increased inositolphospholipid turnover, a mechanism for signal transduction that is widely utilized in animal systems. Samanea motor organs (pulvini) labeled with [(3)H]inositol were irradiated briefly (5-30 sec) with white light, and membrane-localized phosphatidylinositol phosphates and their aqueous breakdown products, the inositol phosphates, were examined. After a 15-sec or longer light pulse, labeled phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate decreased and their labeled metabolic products inositol 1,4-bisphosphate and inositol 1,4,5-trisphosphate increased, changes characteristic of inositolphospholipid turnover. We conclude that inositolphospholipid turnover may act as a phototransduction mechanism in Samanea pulvini in a manner that is similar to that reported in animal systems.
journal_name
Proc Natl Acad Sci U S Aauthors
Morse MJ,Crain RC,Satter RLdoi
10.1073/pnas.84.20.7075subject
Has Abstractpub_date
1987-10-01 00:00:00pages
7075-8issue
20eissn
0027-8424issn
1091-6490journal_volume
84pub_type
杂志文章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::Global demand for agricultural products such as food, feed, and fuel is now a major driver of cropland and pasture expansion across much of the developing world. Whether these new agricultural lands replace forests, degraded forests, or grasslands greatly influences the environmental consequences of expansion. Althoug...
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.0910275107
更新日期:2010-09-21 00:00:00
abstract::To understand the pathogenesis that may be induced by human adenovirus type 12 (Ad12), we have generated transgenic mice carrying the Ad12 early region 1 under control of the mouse mammary tumor virus long terminal repeat. Eleven of 11 male founder mice, but only 2 of 12 females, died between 3 to 4 mo of age. Death 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.86.14.5615
更新日期:1989-07-01 00:00:00
abstract::We have developed a procedure for purifying highly specific polyclonal antibodies against 5-methylcytosine. These antibodies were used to probe the distribution of 5-methylcytosine among fractionated nucleosomes of mouse cell chromatin. Our results demonstrate that at least 80% of the 5-methylcytosine is localized in ...
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.80.18.5490
更新日期:1983-09-01 00:00:00
abstract::2-Isopropylmalate synthase (EC 4.1.3.12) of yeast is a mitochondrial enzyme. We now provide evidence showing that a large part of the 2-isopropylmalate synthase activity that is associated with the mitochondria is located in the mitochondrial matrix. In vitro translation of total yeast RNA followed by immunoprecipitat...
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.80.5.1270
更新日期:1983-03-01 00:00:00
abstract::Control of the establishment of cell polarity is an essential function in tissue morphogenesis and renewal that depends on spatial cues provided by the extracellular environment. The molecular role of cell-cell or cell-extracellular matrix (ECM) contacts on the establishment of cell polarity has been well characterize...
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.0609267103
更新日期:2006-12-26 00:00:00
abstract::Using defined oligomers of IgE, our group previously studied the quantitative relationship between the aggregation of the high affinity receptors for IgE (Fc epsilonRI) and the earliest signals initiated by such aggregation: the phosphorylation of tyrosines on the receptor. Notably, at certain doses of the oligomers 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.94.4.1372
更新日期:1997-02-18 00:00:00
abstract::Exposure of Chinese hamster cells to reduced oxygen partial pressure results in a marked enhancement in the frequency of methotrexate resistance and dihydrofolate reductase gene amplification. The frequency of enhanced resistance is a function of the length of exposure to hypoxic conditions and the time after recovery...
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.83.16.5978
更新日期:1986-08-01 00:00:00
abstract::The conservation of developmental functions exerted by Antp-class homeoproteins in protostomes and deuterostomes suggested that homologs with related functions are present in diploblastic animals. Our phylogenetic analyses showed that Antp-class homeodomains belong either to non-Hox or to Hox/paraHox families. Among 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.97.9.4493
更新日期:2000-04-25 00:00:00
abstract::We examined the interaction of ethanol with the gamma-aminobutyric acid (GABA)ergic system in neurons of slices of the rat central amygdala nucleus (CeA), a brain region thought to be critical for the reinforcing effects of ethanol. Brief superfusion of 11-66 mM ethanol significantly increased GABA type A (GABA(A)) re...
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.0437926100
更新日期:2003-02-18 00:00:00
abstract::Single-copy transgenes in Caenorhabditis elegans can be subjected to a potent, irreversible silencing process termed small RNA-induced epigenetic silencing (RNAe). RNAe is promoted by the Piwi Argonaute protein PRG-1 and associated Piwi-interacting RNAs (piRNAs), as well as by proteins that promote and respond to seco...
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.1501979112
更新日期:2015-05-19 00:00:00
abstract::The energetics of the TiO(2) polymorphs (rutile, anatase, and brookite) were studied by high temperature oxide melt drop solution calorimetry. Relative to bulk rutile, bulk brookite is 0.71 +/- 0.38 kJ/mol (6) and bulk anatase is 2.61 +/- 0.41 kJ/mol higher in enthalpy. The surface enthalpies of rutile, brookite, 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.251534898
更新日期:2002-04-30 00:00:00
abstract::Nipah virus (NiV) and Hendra virus are the type species of the highly pathogenic paramyxovirus genus Henipavirus, which can cause severe respiratory disease and fatal encephalitis infections in humans, with case fatality rates approaching 75%. NiV contains two envelope glycoproteins, the receptor-binding G glycoprotei...
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.0804797105
更新日期:2008-07-22 00:00:00
abstract::Astrocytes purified from primary cultures of neonatal rat cerebrum can now be grown in a synthetic medium supplemented with putrescine, prostaglandin F2 alpha, insulin, fibroblast growth factor, and hydrocortisone. These five supplements have a marked synergistic effect on growth when used in combination but have litt...
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.78.11.7205
更新日期:1981-11-01 00:00:00
abstract::By affinity chromatography on heparin-Sepharose, two classes of lipoproteins were separated from high density lipoproteins (HDL) isolated from patients with primary or secondary lecithin:cholesterol acyltransferase (LCATase; EC 2.3.1.43) deficiency and from normal subjects. The unretained fraction, HDL(A), was charact...
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.77.5.2969
更新日期:1980-05-01 00:00:00
abstract::Tight junctions (TJs) play a key role in mediating paracellular ion reabsorption in the kidney. The paracellular pathway in the collecting duct of the kidney is a predominant route for transepithelial chloride reabsorption that determines the extracellular NaCl content and the blood pressure. However, the molecular me...
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.1009399107
更新日期:2010-10-19 00:00:00
abstract::Unit electrical activity was recorded from single neurons in the isolated lumbo-sacral spinal cord of 14- to 19-day chick embryos, in situ. Spinal cord transection was combined with transection of all lumbo-sacral dorsal roots. The spontaneous discharge of cells is confined, for the most part, to the lower two thirds ...
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.66.1.40
更新日期:1970-05-01 00:00:00
abstract::The mechanisms that regulate the ubiquitin (Ub)-proteasome system's own components, although critically important, are largely unknown. Ub, a principal component of the system, must be maintained at adequate levels to support cellular homeostasis under basal and stressed conditions. It was suggested that Ub is degrade...
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.0905746106
更新日期:2009-07-21 00:00:00
abstract::Lines containing two third-chromosome inversions (Arrowhead and Pikes Peak) of Drosophila pseudoobscura selected for fast and slow mating speed were crossed to a multichromosomal, dominant marker inversion stock, and strains with various combinations of chromosomal derivation were tested for their mating activity. Whe...
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.70.2.459
更新日期:1973-02-01 00:00:00
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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.0437965100
更新日期:2003-02-18 00:00:00
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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.0707190104
更新日期:2007-09-25 00:00:00
abstract::Sirtuin 2 (SIRT2) is a sirtuin family deacetylase that directs acetylome signaling, protects genome integrity, and is a murine tumor suppressor. We show that SIRT2 directs replication stress responses by regulating the activity of cyclin-dependent kinase 9 (CDK9), a protein required for recovery from replication arres...
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.1301463110
更新日期:2013-08-13 00:00:00
abstract::The size of virus-specific RNA synthesized in cultured mouse kidney cells infected with polyoma virus was estimated by electrophoresis and sedimentation analysis of RNA extracts from whole cells. Newly synthesized "late" polyoma-specific RNA appears as "giant" molecules of heterogeneous size, up to several times large...
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.68.9.2231
更新日期:1971-09-01 00:00:00
abstract::After five decades of largely serendipitous (albeit formidable) progress, catalyst design in Ziegler-Natta olefin polymerization, i.e., the rational implementation of new active species to target predetermined polyolefin architectures, has ultimately become a realistic ambition, thanks to a much deeper fundamental und...
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.0602856103
更新日期:2006-10-17 00:00:00
abstract::Huntington's disease is caused by the expansion of a polyglutamine (polyQ) tract in the N-terminal exon of huntingtin (HttEx1), but the cellular mechanisms leading to neurodegeneration remain poorly understood. Here we present in situ structural studies by cryo-electron tomography of an established yeast model system ...
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.1717978115
更新日期:2018-04-10 00:00:00
abstract::Models of the Fv portion (containing the variable regions of the heavy and light chains) of two monoclonal anti-alpha (1----6)dextran antibodies, W3129 and 19.1.2, were constructed from amino acid sequences and the known three-dimensional structures of the Fv portions of McPC603 and J539. The modeled combining site 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.85.18.6885
更新日期:1988-09-01 00:00:00
abstract::By the use of a rapid radioautographic screening procedure, two mutants of Bacillus brevis ATCC 8185 that have lost the ability to produce gramicidin have been isolated. These mutants produced normal levels of tyrocidine and sporulated at the same frequency as the parent strain. Their spores, however, were more heat-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.74.2.780
更新日期:1977-02-01 00:00:00
abstract::We have synthesized pulmonary surfactant apoprotein SP-B peptides by solid-phase chemistry and demonstrated their ability to enhance the surface-active properties of synthetic lipid mixtures. The synthetic peptides were reactive with antiserum generated against the native bovine surfactant peptide. Both peptides confe...
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.87.7.2633
更新日期:1990-04-01 00:00:00
abstract::Hypophosphatasia is a heritable form of rickets/osteomalacia with extremely variable clinical expression. Severe forms are inherited in an autosomal recessive fashion; the mode of transmission of mild forms is uncertain. The biochemical hallmark of hypophosphatasia is deficient activity of the tissue-nonspecific isozy...
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.89.20.9924
更新日期:1992-10-15 00:00:00
abstract::Bones from a stratified sedimentary deposit in the Puu Naio Cave site on Maui, Hawaiian Islands, reveal the late Holocene extinction of 19 species of birds. The age of the sediment and associated fauna was determined by direct radiocarbon dating (tandem particle accelerator-mass spectrometer; TAMS) of amino acids extr...
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.84.8.2350
更新日期:1987-04-01 00:00:00