Abstract:
:The membrane currents of chicken embryo fibroblasts (CEFs) transformed by Rous sarcoma virus (RSV) were compared with the currents of their nontransformed counterparts by using the whole-cell patch-clamp technique. In nontransformed CEFs, the main membrane current is a delayed outward K+ current that is sensitive to tetraethylammonium ion but insensitive to 4-aminopyridine. This K+ current is almost independent of the intracellular Ca2+ concentration and becomes completely inactivated at positive membrane potentials with a time constant of about 10 s at +30 mV. In contrast, transformed CEFs exhibit a noninactivating K+ current that strongly depends on the intracellular Ca2+ concentration. This Ca(2+)-dependent K+ current is blocked by the scorpion toxin charybdotoxin with an IC50 value of 19 nM, whereas the K+ current of normal CEFs is insensitive to charybdotoxin (up to 300 nM). The K+ current properties of transformed CEFs were also found after microinjection of purified, enzymatically active pp60v-src into normal CEFs but not after infection of CEFs with the Rous-associated virus RAV5, which lacks the v-src oncogene. Our results suggest that the oncogene product pp60v-src modulates existing K+ channel proteins, leading to profound electrophysiological and pharmacological alterations of the K+ current properties in RSV-transformed CEFs. Furthermore, our experiments identify for the first time K+ channels as possible substrates of pp60v-src.
journal_name
Proc Natl Acad Sci U S Aauthors
Repp H,Draheim H,Ruland J,Seidel G,Beise J,Presek P,Dreyer Fdoi
10.1073/pnas.90.8.3403subject
Has Abstractpub_date
1993-04-15 00:00:00pages
3403-7issue
8eissn
0027-8424issn
1091-6490journal_volume
90pub_type
杂志文章abstract::Imbalances between proinflammatory and proresolving mediators can lead to chronic inflammatory diseases. The balance of arachidonic acid-derived mediators in leukocytes is thought to be achieved through intracellular localization of 5-lipoxygenase (5-LOX): nuclear 5-LOX favors the biosynthesis of proinflammatory leuko...
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.1410851111
更新日期:2014-10-07 00:00:00
abstract::August-Copenhagen-Irish (ACI) rats are unique in that the ovary-intact females develop high incidence of mammary cancers induced solely by hormones upon prolonged exposure to high levels of estrogen alone. Studies have also shown that such prolonged exposure to high-dose estrogen results in human-like aneuploid mammar...
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.0710535105
更新日期:2008-03-04 00:00:00
abstract::We show in climate model experiments that large-scale afforestation in northern mid-latitudes warms the Northern Hemisphere and alters global circulation patterns. An expansion of dark forests increases the absorption of solar energy and increases surface temperature, particularly in regions where the land surface is ...
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.1116706108
更新日期:2012-01-17 00:00:00
abstract::Autoimmune regulator (aire) is a transcription factor that controls the self-reactivity of the T cell repertoire. Although previous results indicate that it exerts this function in part by promoting ectopic expression of a battery of peripheral-tissue antigens in epithelial cells of the thymic medulla, recent data arg...
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.0502670102
更新日期:2005-05-17 00:00:00
abstract::Transposition is a multistep process in which a transposable element DNA sequence moves from its original genetic location to a new site. Early steps in this process include the formation of a transposition complex in which the end sequences of the transposable element are brought together in a structurally precise fa...
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.91.23.10834
更新日期:1994-11-08 00:00:00
abstract::In a field study, we show that a young song sparrow (i) selects his songs from three or four older birds who have neighboring territories, (ii) preferentially learns song types that these tutor neighbors share, and (iii) ultimately sets up his territory next to, or replaces, one of these tutor neighbors. The consequen...
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.91.4.1450
更新日期:1994-02-15 00:00:00
abstract::The regional chromosomal location of the human gene for plasminogen activator inhibitor type 1 (PAI1) was determined by three independent methods of gene mapping. PAI1 was localized first to 7cen-q32 and then to 7q21.3-q22 by Southern blot hybridization analysis of a panel of human and mouse somatic cell hybrids with ...
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.84.23.8548
更新日期:1987-12-01 00:00:00
abstract::Temporal dynamics of urban warming have been extensively studied at the diurnal scale, but the impact of background climate on the observed seasonality of surface urban heat islands (SUHIs) remains largely unexplored. On seasonal time scales, the intensity of urban-rural surface temperature differences ([Formula: see ...
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.1917554117
更新日期:2020-03-31 00:00:00
abstract::Creatine kinase from rabbit muscle has been specifically labeled with a derivative of a nitroxide free radical on the two essential sulfhydryl groups, one per active site. The conformation in the environment of the enzyme-bound free radical and the change in conformation induced upon binding of the substrate, metal ad...
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.64.1.219
更新日期:1969-09-01 00:00:00
abstract::CD4 can physically associate with the CD3-T-cell receptor complex as visualized in cocapping experiments. This association occurs when the T-cell receptor is cross-linked by certain anti-variable region antibodies that appear to induce a conformational change in the receptor such that it associate with CD4. Similar as...
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.86.9.3311
更新日期:1989-05-01 00:00:00
abstract::The Ten-Eleven-Translocation 2 (TET2) gene encodes a member of TET family enzymes that alters the epigenetic status of DNA by oxidizing 5-methylcytosine to 5-hydroxymethylcytosine (5hmC). Somatic loss-of-function mutations of TET2 are frequently observed in patients with diverse myeloid malignancies, including myelody...
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.1112317108
更新日期:2011-08-30 00:00:00
abstract::The fluorescent vital dye rhodamine 123 (Rh-123), which preferentially accumulates in mitochondrial membranes, can be used as a probe to indicate mitochondrial and hence cellular activity. In this study, mouse bone marrow hematopoietic stem cells were subdivided into Rh-123lo, Rh-123med, and Rh-123hi populations. 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.87.19.7433
更新日期:1990-10-01 00:00:00
abstract::Sponges (Porifera), the simplest and earliest multicellular organisms, are thought to have evolved from their unicellular ancestors about 1 billion years ago by developing cell-recognition and adhesion mechanisms to discriminate against "non-self." Consequently, they are used as models for investigating recognition ph...
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.151111298
更新日期:2001-07-31 00:00:00
abstract::Changes in external light patterns can alter cell activities in peripheral tissues through slow entrainment of the central clock in suprachiasmatic nucleus (SCN). It remains unclear whether cells in otherwise photo-insensitive tissues can achieve rapid responses to changes in external light. Here we show that light 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.1719548115
更新日期:2018-07-17 00:00:00
abstract::Horse heart cytochrome c can be split with cyanogen bromide into a heme peptide (residues 1-65) and a nonheme peptide (residues 66-104). In a process involving (i) complex formation between the two fragments and (ii) restoration of the severed peptide linkage, a fully active cytochrome c preparation can be re-formed. ...
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.74.10.4248
更新日期:1977-10-01 00:00:00
abstract::Snakes are limbless predators, and many species use venom to help overpower relatively large, agile prey. Snake venoms are complex protein mixtures encoded by several multilocus gene families that function synergistically to cause incapacitation. To examine venom evolution, we sequenced and interrogated the genome 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.1314702110
更新日期:2013-12-17 00:00:00
abstract::The sterol regulatory element-binding protein (SREBP) family of transcription factors controls the biosynthesis of cholesterol and other lipids, and lipid synthesis is critical for cell growth and proliferation. We were, therefore, interested in the expression and activity of SREBPs during the cell cycle. We found tha...
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.0501494102
更新日期:2005-08-16 00:00:00
abstract::The natural history of follicular lymphoma (FL) is frequently characterized by transformation to a more aggressive diffuse large B cell lymphoma (DLBCL). We compared the gene-expression profiles between transformed DLBCL and their antecedent FL. No genes were observed to increase or decrease their expression in all 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.132253599
更新日期:2002-06-25 00:00:00
abstract::The matrix of second derivatives of 21 apparent local energy minima of deca-L-alanine has been computed. The results show that all these conformations are true local energy minima and, therefore, potentially stable conformations for this peptide. Calculations of the relative statistical weights of these conformations ...
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.63.2.242
更新日期:1969-06-01 00:00:00
abstract::The 1H NMR signal from oxymyoglobin, a low-concentration diamagnetic protein, is visible in myocardial tissue. The methyl group of the Val-E11 resonates in a clear spectral region at -2.76 ppm and responds to dynamic changes in cellular oxygenation. With CO, the signal shifts to -2.4 ppm. The Val-E11 peak assignment 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.89.10.4731
更新日期:1992-05-15 00:00:00
abstract::Recent work with prion diseases and synucleinopathies indicates that accurate diagnostic methods for protein-folding diseases can be based on the ultrasensitive, amplified measurement of pathological aggregates in biospecimens. A better understanding of the physicochemical factors that control the seeded polymerizatio...
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.1909322116
更新日期:2019-11-12 00:00:00
abstract::This study demonstrates that significantly shortened telomeres are a hallmark of cardiomyocytes (CMs) from individuals with end-stage hypertrophic cardiomyopathy (HCM) or dilated cardiomyopathy (DCM) as a result of heritable defects in cardiac proteins critical to contractile function. Positioned at the ends of chromo...
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.1714538115
更新日期:2018-09-11 00:00:00
abstract::The formation of several acyl groups and an amide group of Taxol is catalyzed by regioselective CoA thioester-dependent acyltransferases. Several full-length acyltransferase sequences, obtained from a cDNA library constructed from mRNA isolated from Taxus cuspidata cells induced for Taxol production with methyl jasmon...
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.082115799
更新日期:2002-07-09 00:00:00
abstract::A cell line has been developed from the imaginal wing discs of the lepidopteran insect Trichoplusia ni (Hübner). The cells grow in suspension as fluid-filled, multicellular vesicles. The cell line has been designated IAL-TND1. Two-dimensional electrophoresis (isoelectric focusing and sodium dodecyl sulfate/polyacrylam...
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.79.8.2589
更新日期:1982-04-01 00:00:00
abstract::T cells transferred into severe lymphopenic hosts undergo rapid proliferation known as "endogenous proliferation" that are distinct from conventional homeostatic proliferation. Unlike homeostatic proliferation, cytokines, such as IL-7 are dispensable, yet TCR:MHC interaction is essential for this process to occur. How...
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.0909954106
更新日期:2009-12-01 00:00:00
abstract::The tumor suppressor activity of p53 is regulated by interactions with the ubiquitin ligase HDM2 and the general transcriptional coactivators CBP and p300. Using NMR spectroscopy and isothermal titration calorimetry, we have dissected the binding interactions between the N-terminal transactivation domain (TAD) of p53,...
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.0811023106
更新日期:2009-04-21 00:00:00
abstract::Advanced personalized medical diagnostics depend on the availability of high-quality biological samples. These are typically biofluids, such as blood, saliva, or urine; and their collection and storage is critical to obtain reliable results. Without proper temperature regulation, protein biomarkers in particular can 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.1602493113
更新日期:2016-05-24 00:00:00
abstract::Fragility is an empirical property that describes how abruptly a glass-forming material solidifies upon supercooling. The degree of fragility carries important implications for the functionality and processability of a material, as well as for our fundamental understanding of the glass transition. However, the microst...
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.1912571116
更新日期:2019-12-10 00:00:00
abstract::The uncatalyzed reactions of O(2) (S = 1) with organic substrates (S = 0) are thermodynamically favorable but kinetically slow because they are spin-forbidden and the one-electron reduction potential of O(2) is unfavorable. In nature, many of these important O(2) reactions are catalyzed by metalloenzymes. In the case ...
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.0704191104
更新日期:2007-11-20 00:00:00
abstract::Current theory indicates that mitochondria were obtained 1.5 billion years ago from an ancient prokaryote. The mitochondria provided the capacity for aerobic respiration, the creation of the eukaryotic cell, and eventually complex multicellular organisms. Recent reports have found that mitochondria play essential role...
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.0510511103
更新日期:2006-01-31 00:00:00