Search results for "ACTIVATOR"
showing 10 items of 488 documents
<title>Spatial correlation of latent image centers active in photostimulable luminescence of irradiated doped alkali halides</title>
2001
Changes in the photostimulated luminescence (PSL) spectrum of an electron irradiated KBr:Tl single crystal in relation to the A-luminescence spectrum upon direct activator ion excitation in the A-absorption band (AL) are found. Based on the view about the spatial correlation between F and activator hole centers, it is suggested that anion vacancy is an additional perturbing factor fot he activator (Tl+) excited (p-electron) state which is already subject to the dynamical Jahn-Teller effect. Dependences of the PSL efficiency on activator (In+) concentration in KBr:In samples irradiated by UV-light (6.30-6.45 eV), X-rays (30 keV or electrons (5.6 keV), are compared. The possible role of 6.45 …
Binding of Tat Protein to TAR Region of Human Immunodeficiency Virus Type 1 Blocks TAR-Mediated Activation of (2′-5′)Oligoadenylate Synthetase
1990
The TAR sequence of the 5' leader of HIV-1 long terminal repeat-directed mRNA was found to be able to bind to and to activate double-stranded RNA-dependent (2'-5')A synthetase. Binding of TAR to the purified synthetase in vitro was abolished by addition of HIV-1 Tat protein, which binds to this sequence with a high affinity. Inhibition of TAR-mediated activation of (2'-5')A synthetase by Tat was prevented in the presence of the Zn2+ and Cd2+ chelators o-phenanthroline and penicillamine, which did not impair TAR-synthetase interaction. Transient expression assays of bacterial chloramphenicol acetyltransferase (CAT) gene in HeLa cells revealed that the levels of both CAT mRNA and CAT protein …
Enhancer blocking activity located near the 3′ end of the sea urchin early H2A histone gene
1997
The sea urchin early histone repeating unit contains one copy of each of the five histone genes whose coordinate expression during development is regulated by gene-specific elements. To learn how within the histone repeating unit a gene-specific activator can be prevented to communicate with the heterologous promoters, we searched for domain boundaries by using the enhancer blocking assay. We focused on the region near the 3′ end of the H2A gene where stage-specific nuclease cleavage sites appear upon silencing of the early histone genes. We demonstrated that a DNA fragment of 265 bp in length, defined as sns (for silencing nucleoprotein structure), blocked the enhancer activity of the H2A…
Cabut/dTIEG associates with the transcription factor Yorkie for growth control
2015
The Drosophila transcription factor Cabut/dTIEG (Cbt) is a growth regulator, whose expression is modulated by different stimuli. Here, we determine Cbt association with chromatin and identify Yorkie (Yki), the transcriptional co-activator of the Hippo (Hpo) pathway as its partner. Cbt and Yki co-localize on common gene promoters, and the expression of target genes varies according to changes in Cbt levels. Down-regulation of Cbt suppresses the overgrowth phenotypes caused by mutations in expanded (ex) and yki overexpression, whereas its up-regulation promotes cell proliferation. Our results imply that Cbt is a novel partner of Yki that is required as a transcriptional co-activator in growth…
Metabolomics of the effect of AMPK activation by AICAR on human umbilical vein endothelial cells
2011
AMP-activated protein kinase (AMPK) is a metabolic master switch expressed in a great number of cells and tissues. AMPK is thought to modulate the cellular response to different stresses that increase cellular AMP concentration. The adenosine analog, 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR) is an AMPK activator used in many studies to assess the effects of AMPK activation on cellular metabolism and function. However, the effect of AICAR on cell metabolism reaches many different pathways and metabolites, some of which do not seem to be fully related to AMPK activation. We have now for the first time used NMR metabolomics on human umbilical vein endothelial cells (HUVEC) fo…
International consensus and practical guidelines on the gynecologic and obstetric management of female patients with hereditary angioedema caused by …
2012
Background There are a limited number of publications on the management of gynecologic/obstetric events in female patients with hereditary angioedema caused by C1 inhibitor deficiency (HAE-C1-INH). Objective We sought to elaborate guidelines for optimizing the management of gynecologic/obstetric events in female patients with HAE-C1-INH. Methods A roundtable discussion took place at the 6th C1 Inhibitor Deficiency Workshop (May 2009, Budapest, Hungary). A review of related literature in English was performed. Results Contraception : Estrogens should be avoided. Barrier methods, intrauterine devices, and progestins can be used. Pregnancy : Attenuated androgens are contraindicated and should …
Possible mechanism of energy storage in optically stimulable materials: doped alkali halides
1997
Radiation-induced effects in doped alkali halides, mainly in KBr:In, are studied by the luminescence technique. The activator luminescence during a 10 s under UV-light or electron irradiation and, after it, the pulsed photostimulated luminescence on a phosphorescence background were investigated. The obtained results allow us to conclude that the main host lattice excitation relevant to both the luminescence processes mentioned above is a very mobile excitonic excitation including a photon phase and the self- trapped exciton in its composition. The photon phase, as we suppose, represents a free exciton luminescence at room temperature. In this phase, via multiple reabsorption in the low-ene…
Hemocyanin conformational changes associated with SDS-induced phenol oxidase activation.
2007
The enzymatic activity of phenoloxidase is assayed routinely in the presence of SDS. Similar assay conditions elicit phenoloxidase activity in another type 3 copper protein, namely hemocyanin, which normally functions as an oxygen carrier. The nature of the conformational changes induced in type 3 copper proteins by the denaturant SDS is unknown. This comparative study demonstrates that arthropod hemocyanins can be converted from being an oxygen carrier to a form which exhibits phenoloxidase activity by incubation with SDS, with accompanying changes in secondary and tertiary structure. Structural characterisation, using various biophysical methods, suggests that the micellar form of SDS is …
Ikaros-1 couples cell cycle arrest of late striatal precursors with neurogenesis of enkephalinergic neurons
2010
et al.
LrhA as a new transcriptional key regulator of flagella, motility and chemotaxis genes in Escherichia coli
2002
The function of the LysR-type regulator LrhA of Escherichia coli was defined by comparing whole-genome mRNA profiles from wild-type E. coli and an isogenic lrhA mutant on a DNA microarray. In the lrhA mutant, a large number (48) of genes involved in flagellation, motility and chemotaxis showed relative mRNA abundances increased by factors between 3 and 80. When a representative set of five flagellar, motility and chemotaxis genes was tested in lacZ reporter gene fusions, similar factors for derepression were found in the lrhA mutant. In gel retardation experiments, the LrhA protein bound specifically to flhD and lrhA promoter DNA (apparent K-D approximate to 20 nM), whereas the promoters of…