Search results for "regulation"
showing 10 items of 4463 documents
Urokinase activates macrophage PON2 gene transcription via the PI3K/ROS/MEK/SREBP-2 signalling cascade mediated by the PDGFR-β
2009
Aims We have recently shown that urokinase plasminogen activator (uPA) increases oxidative stress (OS), cholesterol biosynthesis, and paraoxonase 2 (PON2) expression in macrophages via binding to its receptor, the uPAR. Since PON2 is regulated by both OS and cholesterol content, we hypothesized that uPA elicits a cascade of signal transduction events shared by NADPH oxidase and cholesterol biosynthesis that culminates in PON2 gene expression. Here, we investigated the signalling pathway that leads to the expression of PON2 in macrophages in response to uPA. Methods and results The increase in macrophage PON2 mRNA levels in response to uPA was shown to depend on PON2 gene promoter activation…
TREND-DB—a transcriptome-wide atlas of the dynamic landscape of alternative polyadenylation
2020
AbstractAlternative polyadenylation (APA) profoundly expands the transcriptome complexity. Perturbations of APA can disrupt biological processes, ultimately resulting in devastating disorders. A major challenge in identifying mechanisms and consequences of APA (and its perturbations) lies in the complexity of RNA 3’end processing, involving poorly conserved RNA motifs and multi-component complexes consisting of far more than 50 proteins. This is further complicated in that RNA 3’end maturation is closely linked to transcription, RNA processing, and even epigenetic (histone/DNA/RNA) modifications. Here we present TREND-DB (http://shiny.imbei.uni-mainz.de:3838/trend-db), a resource cataloging…
Expression levels of a filament-specific transcriptional regulator are sufficient to determine Candida albicans morphology and virulence
2009
Candida albicans , the major human fungal pathogen, undergoes a reversible morphological transition from single yeast cells to pseudohyphal and hyphal filaments (elongated cells attached end-to-end). Because typical C. albicans infections contain a mixture of these morphologies it has, for many years, been difficult to assess the relative contribution of each form to virulence. In addition, the regulatory mechanisms that determine growth in pseudohyphal and hyphal morphologies are largely unknown. To address these questions we have generated a C. albicans strain that can be genetically manipulated to grow completely in the hyphal form under non-filament-inducing conditions in vitro. This w…
Developmental dynamics of PAFAH1B subunits during mouse brain development.
2012
Platelet-activating factor (PAF) mediates an array of biological processes in the mammalian central nervous system as a bioactive lipid messenger in synaptic function and dysfunction (plasticity, memory, and neurodegeneration). The intracellular enzyme that deacetylates the PAF (PAFAH1B) is composed of a tetramer of two catalytic subunits, ALPHA1 (PAFAH1B3) and ALPHA2 (PAFAH1B2), and a regulatory dimer of LIS1 (PAFAH1B1). We have investigated the mouse PAFAH1B subunit genes during brain development in normal mice and in mice with a hypomorphic allele for Lis1 (Lis1/sLis1; Cahana et al. [2001] Proc Natl Acad Sci U S A 98:6429–6434). We have analyzed quantitatively (by means of real-time poly…
mTOR Driven Gene Transcription Is Required for Cholesterol Production in Neurons of the Developing Cerebral Cortex
2021
AbstractDysregulated mammalian target of rapamycin (mTOR) activity is associated with various neurodevelopmental disorders ranging from idiopathic autism spectrum disorders to syndromes caused by single gene defects. This suggests that maintaining mTOR activity levels in a physiological range is essential for brain development and functioning. Upon activation, mTOR regulates a variety of cellular processes such as cell growth, autophagy and metabolism. On a molecular level, however, the consequences of mTOR activation in the brain are not well understood.Low levels of cholesterol are associated with a wide variety of neurodevelopmental disorders. We here describe numerous genes of the stero…
Regulation ofMUC1Expression in Human Mammary Cell Lines by the c-ErbB2 and Ras Signaling Pathways
2001
The MUC1 protein is a highly O-glycosylated transmembrane molecule that is expressed at the luminal surface of most glandular epithelial cells and is upregulated in carcinomas. Here, we report the effect of the activation of the c-ErbB2 --Ras pathway on the expression of the MUC1 gene in the nontumorigenic mammary cell lines MTSV1-7 and HB2 and in the malignant cell lines T47D and ZR75. Endogenous levels of MUC1 mRNA and protein in HB2 clones permanently overexpressing c-ErbB2 or V12-H-Ras were markedly reduced compared with levels in the parental cell lines. Furthermore, in transient transfection assays, the transcription of a CAT reporter construct driven by the MUC1 promoter was inhibite…
Characterization and DNA-binding properties of GRF, a novel monomeric binding orphan receptor related to GCNF and betaFTZ-F1
1999
0014-2956 (Print) Comparative Study Journal Article Research Support, Non-U.S. Gov't; A PCR approach has been used to isolate, from Bombyx mori, a cDNA encoding a novel orphan receptor (GRF) that is most closely related to Bombyx betaFTZ-F1 and to the vertebrate germ cell nuclear factor. The major GRF mRNA is detected in most tissues as an 8-kb transcript whose amount follows the circulating ecdysteroid concentration with a delay. The expression pattern of GRF is similar to that of the Bombyx homologue of the Drosophila early-late gene DHR3, and precedes that of betaFTZ-F1 in all stages and tissues examined. The GRF protein is thus likely to be required in many tissues, but in a temporally …
ADR1 and SNF1 Mediate Different Mechanisms in Transcriptional Regulation of Yeast POT1 Gene
1994
We studied the consequences of adr1 and snf1 mutations on POT1 gene expression in different growth conditions. The results obtained reveal that ADR1 and SNF1 genes affect POT1 transcription in different ways: ADR1 has a minor role in derepression in low concentration of glucose but is essential for activation in stationary phase whereas SNF1 is essential for derepression and activation, although it does not seem to be directly involved in the molecular mechanism of activation in stationary phase.
Genome-wide analysis of factors regulating gene expression in liver
2007
In recent decades, multiple individual genes have been studied with respect to their level of expression in liver tissue and in many cases substantial progress has been made in identifying individual factors promoting gene expression in liver. However, the overall picture is still undefined and general rules or factors regulating gene expression in liver have not yet been established. Thus, a genome-wide screen for factors regulating gene expression in liver is of high interest, as it may reveal common regulatory mechanisms for most genes highly expressed in liver. These factors represent potential new targets in liver disease associated with differential gene expression. Using a novel bioi…
A new glucose-repressible gene identified from the analysis of chromatin structure in deletion mutants of yeast SUC2 locus.
1991
We have previously shown that some changes occur in the chromatin structure of the 3' flank of the yeast SUC2 gene in going from a repressed to an active state. In an attempt to find out the causes of these changes, we have carried out experiments in which mutant copies of SUC2 locus lacking either 5' or 3' flanks have been analysed for their transcriptional activity and chromatin structure. These experiments allowed us to discard any relationship between SUC2 transcription and chromatin changes within its 3'flank. Sequencing of this flank and mRNA analysis, however, resulted in the location of a putative peroxisomal 3-oxoacyl-CoA thiolase gene (POT1), which is repressible by glucose. The d…