Abstract:
:Members of the ras gene family are activated as oncogenes in many different human cancers. To systematically determine the frequency at which such genes might be involved in the neoplastic process affecting a specific target tissue, urothelial cells, we surveyed a large series of urinary tract tumors for ras oncogenes by DNA transfection and by molecular genetic analysis. Harvey (Ha)-ras oncogenes were detected in 2 of 38 tumors by transfection, molecularly cloned in biologically active form, and shown to contain single base changes at codon 61 leading to substitutions of arginine and leucine, respectively, for glutamine at this position. One additional Ha-ras oncogene was identified in a bladder carcinoma by restriction polymorphisms at codon 12. In one of 21 tumors, we observed a 40-fold amplification of the Kirsten (Ki)-ras gene. No amplification of other ras genes was detected in any of the tumors analyzed. Our findings strengthen the conclusion that codons 12 and 61 are the major "hot spots" of ras oncogene activation and suggest that quantitative alterations in expression due to gene amplification may provide an alternative mechanism for ras gene activation in primary human tumors.
journal_name
Proc Natl Acad Sci U S Aauthors
Fujita J,Srivastava SK,Kraus MH,Rhim JS,Tronick SR,Aaronson SAdoi
10.1073/pnas.82.11.3849subject
Has Abstractpub_date
1985-06-01 00:00:00pages
3849-53issue
11eissn
0027-8424issn
1091-6490journal_volume
82pub_type
杂志文章abstract::Intrinsically disordered proteins (IDPs) are involved in a wide range of regulatory processes in the cell. Owing to their flexibility, their conformations are expected to be particularly sensitive to the crowded cellular environment. Here we use single-molecule Förster resonance energy transfer to quantify the effect ...
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.1322611111
更新日期:2014-04-01 00:00:00
abstract::The effect of 6 days' s.c. infusions of angiotensin II at increasing doses was determined on the uptake of rat or human low density lipoprotein (LDL) and of human fibrinogen by aorta in normal and spontaneously hypertensive rats. Rat or human LDL or human fibrinogen was injected i.v. 5 days after the start of infusion...
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.91.8.3285
更新日期:1994-04-12 00:00:00
abstract::Experimental intramolecular vibrational dephasing transients for several large organic molecules are reanalyzed. Fits to the experimental data, as well as full numerical quantum calculations with a factorized potential surface for all active degrees of freedom of fluorene indicate that power law decays, not exponentia...
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.95.11.5965
更新日期:1998-05-26 00:00:00
abstract::The c-myc oncogene has been implicated in a wide spectrum of B-cell neoplasias. In normal cells, the level of expression of the c-myc gene correlates with growth status. In the present study, we examined the effect of receptor-mediated inhibition of growth on c-myc expression in a B-cell lymphoma. The murine lymphoma ...
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.81.17.5546
更新日期:1984-09-01 00:00:00
abstract::Climate warming is expected to mobilize northern permafrost and peat organic carbon (PP-C), yet magnitudes and system specifics of even current releases are poorly constrained. While part of the PP-C will degrade at point of thaw to CO2 and CH4 to directly amplify global warming, another part will enter the fluvial ne...
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.1811797116
更新日期:2019-05-21 00:00:00
abstract::We demonstrate theoretically and experimentally the spontaneous clustering of solitons in partially coherent wavefronts during the final stages of pattern formation initiated by modulation instability and noise. ...
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.072287299
更新日期:2002-04-16 00:00:00
abstract::The charge-stabilization effect associated with alpha-helices in proteins has been reexamined by microscopic calculations without any a priori assumptions about the dielectric constant of the protein. The calculations reproduce the observed charge stabilization effect of a helix in two well-defined test cases: a histi...
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.88.5.2026
更新日期:1991-03-01 00:00:00
abstract::The organization and allelic recombination of the merozoite surface protein-1 gene of Plasmodium vivax (PvMsp-1), the most widely prevalent human malaria parasite, were evaluated in complete nucleotide sequences of 40 isolates from various geographic areas. Alignment of 31 distinct alleles revealed the mosaic organiza...
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.252348999
更新日期:2002-12-10 00:00:00
abstract::The fluxes of arginine and citrulline through plasma and the rate of conversion of labeled citrulline to arginine were estimated in two pilot studies (with a total of six adult subjects) and in a dietary study with five healthy young men. These latter subjects received an L-amino acid-based diet that was arginine-rich...
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.90.16.7749
更新日期:1993-08-15 00:00:00
abstract::Phosphatidylinositol (3,4,5)-triphosphate (PtdInsP(3)) mediates intracellular signaling for directional sensing and pseudopod extension at the leading edge of migrating cells during chemotaxis. How this PtdInsP(3) signal is translated into remodeling of the actin cytoskeleton is poorly understood. Here, using a proteo...
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.1006153107
更新日期:2010-06-29 00:00:00
abstract::Activation of eukaryotic class II gene expression involves the formation of a transcription initiation complex that includes RNA polymerase II, general transcription factors, and SRB components of the holoenzyme. Negative regulators of transcription have been described, but it is not clear whether any are general repr...
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.94.7.3145
更新日期:1997-04-01 00:00:00
abstract::This study uses a multiisotope (carbon, nitrogen, oxygen, and strontium) approach to examine early animal management in the Maya region. An analysis of faunal specimens across almost 2,000 years (1000 BC to AD 950) at the site of Ceibal, Guatemala, reveals the earliest evidence for live-traded dogs and possible captiv...
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.1713880115
更新日期:2018-04-03 00:00:00
abstract::This is a multinanosecond molecular dynamics study of a bio-nano complex formed by a carbon nanoparticle, a buckyball C(60), and a biological molecule, an antibody, with high binding affinity and specificity. In the simulation, the ball is completely desolvated by the binding site of the antibody by means of a nearly ...
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.022532599
更新日期:2002-04-30 00:00:00
abstract::Although anatomy is often the first step in assigning functions to neural structures, it is not always clear whether architecturally distinct regions of the brain correspond to operational units. Whereas neuroarchitecture remains relatively static, functional connectivity may change almost instantaneously according 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.1514415112
更新日期:2015-10-06 00:00:00
abstract::We report the molecular cloning of the first beta-1,3 glucanase from animal tissue. Three peptide sequences were obtained from beta-1,3 glucanase that had been purified from eggs of the sea urchin Strongylocentrotus purpuratus and the gene was cloned by PCR using oligonucleotides deduced from the peptide sequences. Th...
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.93.13.6808
更新日期:1996-06-25 00:00:00
abstract::The absence of tools for mapping the forces that drive morphogenetic movements in embryos has impeded our understanding of animal development. Here we describe a unique approach, video force microscopy (VFM), that allows detailed, dynamic force maps to be produced from time-lapse images. The forces at work in an embry...
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.1006591107
更新日期:2010-12-21 00:00:00
abstract::NaeI is a remarkable type II restriction endonuclease. It must bind two recognition sequences to cleave DNA, forms a covalent protein-DNA intermediate, and is only 1 aa change away from topoisomerase and recombinase activity. The latter activities apparently derive from reactivation of a cryptic DNA ligase active site...
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.95.7.3531
更新日期:1998-03-31 00:00:00
abstract::Clustered DNA damage induced by ionizing radiation is refractory to repair and may trigger carcinogenic events for reasons that are not well understood. Here, we used an in situ method to directly monitor induction and repair of clustered DNA lesions in individual cells. We showed, consistent with biophysical modeling...
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.1016045108
更新日期:2011-05-17 00:00:00
abstract::In the mammalian visual system, the terminal arbors of retinal ganglion cell axons from the two eyes are restricted to mutually exclusive territories within their thalamic target, the lateral geniculate nucleus (LGN). Here we have investigated some of the factors that determine the adult morphology of terminal arbors ...
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.85.19.7361
更新日期:1988-10-01 00:00:00
abstract::The endometrial epithelium of the uterus regenerates periodically. The cellular source of newly regenerated endometrial epithelia during a mouse estrous cycle or a human menstrual cycle is presently unknown. Here, I have used single-cell lineage tracing in the whole mouse uterus to demonstrate that epithelial stem cel...
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.1814597116
更新日期:2019-04-02 00:00:00
abstract::Without sufficient greenhouse gases in the atmosphere, the early Earth would have become a permanently frozen planet because the young Sun was less luminous than it is today. Several resolutions to this faint young Sun-frozen Earth paradox have been proposed, with an atmosphere rich in CO2 being the one generally favo...
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.91.4.1248
更新日期:1994-02-01 00:00:00
abstract::Ring-shaped hexameric helicases and translocases support essential DNA-, RNA-, and protein-dependent transactions in all cells and many viruses. How such systems coordinate ATPase activity between multiple subunits to power conformational changes that drive the engagement and movement of client substrates is a fundame...
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.1616745113
更新日期:2016-11-29 00:00:00
abstract::Hepatocytes polarize by forming functionally distinct sinusoidal (basolateral) and canalicular (apical) plasma membrane domains. Two distinct routes are used for delivery of membrane proteins to the canaliculus. Proteins having glycosylphosphatidylinositol anchors or single transmembrane domains are targeted to the si...
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.0503702102
更新日期:2005-10-18 00:00:00
abstract::Gene III protein of bacteriophage f1 is inserted into the host cell membrane where it is assembled into phage particles. A truncated form of gene III protein, encoded by a recombinant plasmid and lacking the carboxyl terminus, does not remain in the membrane but instead appears to slip through it. Fusion of a hydropho...
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.79.17.5200
更新日期:1982-09-01 00:00:00
abstract::We find that the transcription of various ribosomal proteins can be differentially affected by polyamines and by changes in growth rates. Using strain MG1655 of Escherichia coli K-12 (F-, lambda-), we have determined the effects of polyamines and changes in growth rate on the transcription of several ribosomal genes 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.87.9.3464
更新日期:1990-05-01 00:00:00
abstract::Purified human platelet-derived growth factor (PDGF) induces an increase in amino acid uptake via system A in quiescent human diploid fibroblasts. Cells must be exposed to PDGF for 45 min to obtain maximum transport stimulation. Transport stimulation requires protein synthesis. Transient exposure to PDGF, alone, in th...
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.79.10.3203
更新日期:1982-05-01 00:00:00
abstract::The complex biomechanical events associated with embryo development are investigated in vivo, by using femtosecond laser pulse-induced ablation combined with multimodal nonlinear microscopy. We demonstrate controlled intravital ablations preserving local cytoskeleton dynamics and resulting in the modulation of specifi...
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.0405316102
更新日期:2005-01-25 00:00:00
abstract::Successful implementation of bone marrow transplantation for hematopoietic reconstitution is limited by the lack of suitably HLA-matched donors and by the occurrence of graft-versus-host disease that frequently accompanies this procedure. Recent clinical reports have implied that the use of umbilical cord blood as a 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.89.21.10006
更新日期:1992-11-01 00:00:00
abstract::One of the issues currently being debated in the ongoing discussion of the pros and cons of today's globalization concerns the effects of greater world trade as well as of the changes in technology on a country's internal distribution of income, especially on skilled versus unskilled wage rates. In this article, I att...
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.1733335100
更新日期:2003-09-16 00:00:00
abstract::Twenty-four hours after rats receive choline chloride (20 mmol/kg, by stomach tube) the activity of tyrosine hydroxylase [tyrosine 3-monooxygenase; L-tyrosine, tetrahydropteridine:oxygen oxidoreductase (3-hydroxylating), EC 1.14.16.2] increases by 31% within adrenomedullary chromaffin cells. This treatment also causes...
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.74.2.798
更新日期:1977-02-01 00:00:00