Abstract:
:Integration of viral DNA into the host nuclear genome, although not unusual in bacterial and animal systems, has surprisingly not been reported for plants. We have discovered geminvirus-related DNA (GRD) sequences, in the form of distinct sets of multiple direct repeats comprising three related repeat classes, situated in a unique locus in the Nicotiana tabacum (tobacco) nuclear genome. The organization of these sequences is similar or identical in eight different tobacco cultivars we have examined. DNA sequence analysis reveals that each repeat has sequences most resembling those of the New World geminiviral DNA replication origin plus the adjacent AL1 gene, encoding the viral replication protein. We believe these GRD sequences originated quite recently in Nicotiana evolution through integration of geminiviral DNA by some combination of the processes of illegitimate recombination, amplification, deletions, and rearrangements. These events must have occurred in plant tissue that was subsequently able to contribute to meristematic tissue yielding gametes. GRD may have been retained in tobacco by selection or by random fixation in a small evolving population. Although we cannot detect transcription of these sequences, this does not exclude the possibility that they may originally have been expressed.
journal_name
Proc Natl Acad Sci U S Aauthors
Bejarano ER,Khashoggi A,Witty M,Lichtenstein Cdoi
10.1073/pnas.93.2.759subject
Has Abstractpub_date
1996-01-23 00:00:00pages
759-64issue
2eissn
0027-8424issn
1091-6490journal_volume
93pub_type
杂志文章abstract::The corticotropin-releasing factor (CRF) ligand family has diverse effects on the CNS, including the modulation of the stress response. The ligands' effects are mediated by binding to CRF G protein-coupled receptors. We have determined the 3D NMR structure of the N-terminal extracellular domain (ECD1) of the mouse CRF...
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.0404702101
更新日期:2004-08-31 00:00:00
abstract::Although melanomas with mutant v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) can now be effectively targeted, there is no molecular target for most melanomas expressing wild-type BRAF. Here, we show that the activation of Pleckstrin homology domain-interacting protein (PHIP), promotes melanoma metastasis, can ...
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.1119949109
更新日期:2012-05-01 00:00:00
abstract::The myocardin family proteins (myocardin, MRTF-A, and MRTF-B) are serum response factor (SRF) cofactors and potent transcription activators. Gene-ablation studies have indicated important developmental functions for myocardin family proteins primarily in regulation of cardiac and smooth muscle development. Using Xenop...
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.0703918105
更新日期:2008-02-05 00:00:00
abstract::Human T lymphotropic virus type 1 (HTLV-1) -associated myelopathy/tropic spastic paraparesis is a demyelinating inflammatory neurologic disease associated with HTLV-1 infection. HTLV-1 Tax11-19-specific cytotoxic T cells have been isolated from HLA-A2-positive patients. We have used a peptide-loaded soluble HLA-A2-Ig ...
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.95.13.7568
更新日期:1998-06-23 00:00:00
abstract::The extinction of a species is inevitably preceded by the extirpation of a series of local populations. Ecological theory predicts that vulnerability to extirpation varies between populations and is ultimately linked to environmental heterogeneity. If populations of a species are present in multiple regions separated ...
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.1015097108
更新日期:2011-03-08 00:00:00
abstract::Non-human primates (NHP) provide crucial research models. Their strong similarities to humans make them particularly valuable for understanding complex behavioral traits and brain structure and function. We report here the genetic mapping of an NHP nervous system biologic trait, the cerebrospinal fluid (CSF) concentra...
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.0707640104
更新日期:2007-10-02 00:00:00
abstract::A 1-hr exposure of bovine lenses in organ culture to H2O2 concentrations in the range found in the aqueous fluid of patients with cataracts inhibits 86Rb+ influx. At 1 mM H2O2, complete inhibition was observed and further investigated. Membrane permeability is slightly decreased. Although lactate concentrations increa...
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.80.7.2044
更新日期:1983-04-01 00:00:00
abstract::A near-full-length casbene synthase cDNA clone, pCS7, was isolated by using a partial cDNA clone, pCS4, to probe a lambda gt10 library constructed from poly(A)+ RNA from elicited castor bean seedlings. The cDNA insert had a length of 1983 bases with a polyadenylate tail of 19 bases. Translation of the cDNA sequence 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.91.18.8497
更新日期:1994-08-30 00:00:00
abstract::Selective lodgement or homing of transplanted hemopoietic stem cells in the recipient's bone marrow (BM) is a critical step in the establishment of long-term hemopoiesis after BM transplantation. However, despite its biologic and clinical significance, little is understood about the process of homing. In the present 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.92.21.9647
更新日期:1995-10-10 00:00:00
abstract::Congenital defects, trauma, and disease can compromise the integrity and functionality of the skeletal system to the extent requiring implantation of bone grafts. Engineering of viable bone substitutes that can be personalized to meet specific clinical needs represents a promising therapeutic alternative. The aim of 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.1301190110
更新日期:2013-05-21 00:00:00
abstract::We have studied the effects of specific ligands of the receptor for the IgG Fc fragment (FcR) on the membrane potential (delta psi) of the macrophage cell line J774 by the [3H]tetraphenylphosphonium ion equilibration technique. We observe a membrane depolarization with binding of FcR ligands that is dependent on the 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.80.5.1357
更新日期:1983-03-01 00:00:00
abstract::One of the advantages of the production of monoclonal antibodies by tissue culture methods is that they can be internally labeled by using appropriate radioactive amino acid in the culture fluid. Thus, radioactive immunological probes of high specific activity can be prepared. Here we report applications of these inte...
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.79.2.665
更新日期:1982-01-01 00:00:00
abstract::Targeted gene modification mediated by single-stranded oligonucleotides (SSOs) holds great potential for widespread use in a number of biological and biomedical fields, including functional genomics and gene therapy. By using this approach, specific genetic changes have been created in a number of prokaryotic and euka...
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.0406991102
更新日期:2005-02-15 00:00:00
abstract::(3)H-actinomycin D, a guanine-binding agent, labels fixed human chromosomes nonrandomly. Actinomycin D added in G2 inhibits secondary constrictions and breaks chromosomes. There is some tendency for label to be concentrated at the ends of chromosomes and near the centromere. Labeling with (3)H-thymidine in the late st...
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.65.3.585
更新日期:1970-03-01 00:00:00
abstract::Mach bands, the illusory brightness maxima and minima perceived at the initiation and termination of luminance gradients, respectively, are generally considered a direct perceptual manifestation of lateral inhibitory interactions among retinal or other lower order visual neurons. Here we examine an alternative explana...
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.96.9.5239
更新日期:1999-04-27 00:00:00
abstract::Chimeric receptors containing different portions of the homologous human insulin receptor, insulin-like growth factor I receptor, and insulin receptor-related receptor were utilized to identify the epitopes recognized by various anti-insulin receptor antibodies. The antibodies studied included 12 monoclonal antibodies...
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.88.21.9858
更新日期:1991-11-01 00:00:00
abstract::The class of neurons within the visual cortex of normal adult cats that has the smallest receptive fields (less than or equal to 2.25 degrees2) and that responds only to low rates of stimulus motion (less than or equal to 50 degrees / sec) responds preferentially to lines oriented about either the horizontal axis (+/-...
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.74.3.1272
更新日期:1977-03-01 00:00:00
abstract::Direct structural insights on the fundamental mechanisms of permeation, selectivity, and gating remain unavailable for the Na(+) and Ca(2+) channel families. Here, we report the spectroscopic structural characterization of the isolated Voltage-Sensor Domain (VSD) of the prokaryotic Na(+) channel NaChBac in a lipid bil...
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.0914109107
更新日期:2010-03-23 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.1006546107
更新日期:2010-10-19 00:00:00
abstract::Prion protein consists of an ensemble of glycosylated variants or glycoforms. The enzymes that direct oligosaccharide processing, and hence control the glycan profile for any given glycoprotein, are often exquisitely sensitive to other events taking place within the cell in which the glycoprotein is expressed. Alterat...
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.96.23.13044
更新日期:1999-11-09 00:00:00
abstract::Historical scenarios of evolution of avian plumage coloration have been called into question with the discoveries that most birds can see UV light (which normal humans cannot), and that UV-reflecting plumages are widespread in birds. Several examples of sexual dichromatism not detectable with human visual capabilities...
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.0501891102
更新日期:2005-08-02 00:00:00
abstract::A surprising example of interspecies competition is the production by certain bacteria of hydrogen peroxide at concentrations that are lethal for others. A case in point is the displacement of Staphylococcus aureus by Streptococcus pneumoniae in the nasopharynx, which is of considerable clinical significance. How it 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.0809600106
更新日期:2009-01-27 00:00:00
abstract::Complete inactivation of the human retinoblastoma gene (RB) is believed to be an essential step in tumorigenesis of several different cancers. To provide a framework for understanding inactivation mechanisms, the structure of RB was delineated. The RB transcript is encoded in 27 exons dispersed over about 200 kilobase...
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.86.14.5502
更新日期:1989-07-01 00:00:00
abstract::Selenophosphate, an activated form of selenium that can serve as a selenium donor, is generated by the selD gene product, selenophosphate synthetase (SPS). Selenophosphate is required by several bacteria and by mammals for the specific synthesis of Secys-tRNA, the precursor of selenocysteine in selenoenzymes. Although...
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.0409042102
更新日期:2005-01-25 00:00:00
abstract::The 72-kDa spleen tyrosine kinase (Syk) and Src-family kinase p53/56Lyn (Lyn) contribute to signaling via the B-cell antigen receptor complex. Here we show that Syk and Lyn from human B lymphocytes can interact directly. Syk and Lyn coimmunoprecipitated from mature and activated B-cell lines, and gel-purified Syk 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.92.2.359
更新日期:1995-01-17 00:00:00
abstract::Monoclonal antibodies provide an attractive alternative to small-molecule therapies for a wide range of diseases. Given the importance of G protein-coupled receptors (GPCRs) as pharmaceutical targets, there has been an immense interest in developing therapeutic monoclonal antibodies that act on GPCRs. Here we present ...
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.1700891114
更新日期:2017-08-01 00:00:00
abstract::We have detected a variant species of bovine growth hormone mRNA in bovine pituitary tissue and in a stably transfected bovine growth hormone-producing cell line. Analysis of this variant mRNA indicated that the last intervening sequence (intron D) had not been removed by splicing. Inspection of the sequence of intron...
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.84.9.2673
更新日期:1987-05-01 00:00:00
abstract::Neither the structure nor the function of alpha-bungarotoxin (alpha Bgtx) binding molecules in the nervous system have yet been completely defined, although it is known that some of these molecules are related to cation channels and some are not. Using an improved method of affinity chromatography, we have isolated 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.88.8.3258
更新日期:1991-04-15 00:00:00
abstract::Cotransfection assays were used to show that the members of the GTP-binding protein Gq class of alpha subunits could activate phospholipase C (PLC) beta 2. Similar experiments also demonstrated that G beta 1 gamma 1, G beta 1 gamma 5, and G beta 2 gamma 5 could activate the beta 2 isoform of PLC but not the beta 1 iso...
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.90.11.5297
更新日期:1993-06-01 00:00:00
abstract::Neuronal signal integration as well as synaptic transmission and plasticity highly depend on the morphology of dendrites and their spines. Nogo-A is a membrane protein enriched in the adult central nervous system (CNS) myelin, where it restricts the capacity of axons to grow and regenerate after injury. Nogo-A is also...
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.1214255110
更新日期:2013-01-15 00:00:00