Search results for "Gene expression"
showing 10 items of 4085 documents
Coordinated Sumoylation and Ubiquitination Modulate EGF Induced EGR1 Expression and Stability
2011
Background Human early growth response-1 (EGR1) is a member of the zing-finger family of transcription factors induced by a range of molecular and environmental stimuli including epidermal growth factor (EGF). In a recently published paper we demonstrated that integrin/EGFR cross-talk was required for Egr1 expression through activation of the Erk1/2 and PI3K/Akt/Forkhead pathways. EGR1 activity and stability can be influenced by many different post-translational modifications such as acetylation, phosphorylation, ubiquitination and the recently discovered sumoylation. The aim of this work was to assess the influence of sumoylation on EGF induced Egr1 expression and/or stability. Methods We …
Comprehensive transcriptional analysis of the oxidative response in yeast
2008
The oxidative stress response in Saccharomyces cerevisiae has been analyzed by parallel determination of mRNA levels and transcription rates for the entire genome. A mathematical algorithm has been adapted for a dynamic situation such as the response to stress, to calculate theoretical mRNA decay rates from the experimental data. Yeast genes have been grouped into 25 clusters according to mRNA level and transcription rate kinetics, and average mRNA decay rates have been calculated for each cluster. In most of the genes, changes in one or both experimentally determined parameters occur during the stress response. 24% of the genes are transcriptionally induced without an increase inmRNAlevels…
Robust dynamical pattern formation from a multifunctional minimal genetic circuit.
2010
Abstract Background A practical problem during the analysis of natural networks is their complexity, thus the use of synthetic circuits would allow to unveil the natural mechanisms of operation. Autocatalytic gene regulatory networks play an important role in shaping the development of multicellular organisms, whereas oscillatory circuits are used to control gene expression under variable environments such as the light-dark cycle. Results We propose a new mechanism to generate developmental patterns and oscillations using a minimal number of genes. For this, we design a synthetic gene circuit with an antagonistic self-regulation to study the spatio-temporal control of protein expression. He…
Persistent episomal transgene expression in liver following delivery of a scaffold/matrix attachment region containing non-viral vector
2008
An ideal gene therapy vector should enable persistent transgene expression without limitations of safety and reproducibility. Here we report the development of a non-viral episomal plasmid DNA (pDNA) vector that appears to fulfil these criteria. This pDNA vector combines a scaffold/matrix attachment region (S/MAR) with a human liver-specific promoter (alpha1-antitrypsin (AAT)) in such a way that long-term expression is enabled in murine liver following hydrodynamic injection. Long-term expression is demonstrated by monitoring the longitudinal luciferase expression profile for up to 6 months by means of in situ bioluminescent imaging. All relevant control pDNA constructs expressing luciferas…
Oxidative stress responses and lipid peroxidation damage are induced during dehydration in the production of dry active wine yeasts.
2009
The tolerance of the yeast Saccharomyces cerevisiae to desiccation is important for the use of this microorganism in the wine industry, since active dry wine yeast is routinely used as starter for must fermentations. Many studies have shown the complexity of the cellular effects caused by water loss, including oxidative injuries on macromolecular components. However the technological interest of yeast drying was not addressed in those studies, and the dehydration conditions were far from the industrial practice. In the present study a molecular approach was used to characterize the relevant injuring conditions during pilot plant dehydrations under two different drying temperatures (i.e., 35…
D2R striatopallidal neurons inhibit both locomotor and drug reward processes.
2009
The specific functions of dopamine D(2) receptor-positive (D(2)R) striatopallidal neurons remain poorly understood. Using a genetic mouse model, we found that ablation of D(2)R neurons in the entire striatum induced hyperlocomotion, whereas ablation in the ventral striatum increased amphetamine conditioned place preference. Thus D(2)R striatopallidal neurons limit both locomotion and, unexpectedly, drug reinforcement.
A complete set of nascent transcription rates for yeast genes
2010
The amount of mRNA in a cell is the result of two opposite reactions: transcription and mRNA degradation. These reactions are governed by kinetics laws, and the most regulated step for many genes is the transcription rate. The transcription rate, which is assumed to be exercised mainly at the RNA polymerase recruitment level, can be calculated using the RNA polymerase densities determined either by run-on or immunoprecipitation using specific antibodies. The yeast Saccharomyces cerevisiae is the ideal model organism to generate a complete set of nascent transcription rates that will prove useful for many gene regulation studies. By combining genomic data from both the GRO (Genomic Run-on) a…
Genome-wide studies of mRNA synthesis and degradation in eukaryotes
2012
In recent years, the use of genome-wide technologies has revolutionized the study of eukaryotic transcription producing results for thousands of genes at every step of mRNA life. The statistical analyses of the results for a single condition, different conditions, different transcription stages, or even between different techniques, is outlining a totally new landscape of the eukaryotic transcription process. Although most studies have been conducted in the yeast Saccharomyces cerevisiae as a model cell, others have also focused on higher eukaryotes, which can also be comparatively analyzed. The picture which emerges is that transcription is a more variable process than initially suspected,…
Transcriptional targeting of dendritic cells for gene therapy using the promoter of the cytoskeletal protein fascin.
2003
Strong cell-type-specific promoters are basic tools in gene therapy allowing for novel applications and focused strategies by transcriptionally targeting gene expression to selected cells. In immunotherapy, dendritic cells (DC) are of central importance, since they represent the principal inducers of immune responses. Here we describe isolation and use of the promoter of the murine actin-bundling protein fascin to target transcriptionally gene expression to cutaneous DC. Using the reporter gene enhanced green fluorescent protein (EGFP), we demonstrate that the fascin promoter mediates a strong antigen expression that is restricted to mature DC. DNA vaccination with antigen-encoding expressi…
Stability of phospholipase D in primary astrocytes.
2002
Induction of expression and proteolytic breakdown of phospholipase D (PLD) isoforms in primary astrocyte cultures have been investigated. Astrocytes express both PLD1 and 2 and are dependent on PLD activity for cell proliferation [K. Kotter, J. Klein, J. Neurochem. 73 (1999) 2517]. Competitive RT-PCR analysis demonstrated a higher level of PLD1 mRNA than PLD2 mRNA (8.9 vs. 0.9amol/microg RNA, respectively). Treatment of astroglial cultures with the phorbol ester, 4beta-phorbol-12beta,13alpha-dibutyrate (0.1 microM), for 24-48h selectively induced PLD1b but not PLD1a or 2 expression as shown by PCR and Western blot; the effect was sensitive to Go 6976. In cells transiently permeabilized with…