Search results for "SoMe"

Nucleosome-specific, Time-dependent Changes in Histone Modifications during Activation of the Early Growth Response 1 (Egr1) Gene

2014

Histone post-translational modifications and nucleosome remodeling are coordinate events involved in eukaryotic transcriptional regulation. There are relatively few data on the time course with which these events occur in individual nucleosomes. As a contribution to fill this gap, we first describe the nature and time course of structural changes in the nucleosomes -2, -1, and +1 of the murine Egr1 gene upon induction. To initiate the transient activation of the gene, we used the stimulation of MLP29 cells with phorbol esters and the in vivo activation after partial hepatectomy. In both models, nucleosomes -1 and +1 are partially evicted, whereas nucleosomes +1 and -2 slide downstream durin…

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…

α-Synuclein expression levels do not significantly affect proteasome function and expression in mice and stably transfected PC12 cell lines

2004

α-Synuclein (α-syn) is a small protein of unknown function that is found aggregated in Lewy bodies, the histopathological hallmark of sporadic Parkinson disease and other synucleinopathies. Mutations in the α-syn gene and a triplication of its gene locus have been identified in early onset familial Parkinson disease. α-Syn turnover can be mediated by the proteasome pathway. A survey of published data may lead to the suggestion that overexpression of α-syn wild type, and/or their variants (A53T and A30P), may produce a decrease in proteasome activity and function, contributing to α-syn aggregation. To investigate the relationship between synuclein expression and proteasome function we have s…

Proteasome comprising a beta1 inducible subunit acts as a negative regulator of NADPH oxidase during elicitation of plant defense reactions.

2005

Elicitation of defense reactions in tobacco by cryptogein, triggered a production of active oxygen species (AOS) via the NADPH oxidase, NtrbohD, and an accumulation of beta1din, a defense induced beta-type subunit of 20S proteasome. The proteasome inhibitor, MG132, stimulated this AOS production. Tobacco cells transformed with sense constructs of beta1din showed an inhibition of the AOS production following elicitin treatment, whereas the antisense transformed cells showed a strongly enhanced AOS production. In cells transformed with sense construct of beta1din, the NtrbohD transcripts failed to be induced by cryptogein as observed in control and antisense transformed cells. Conversely, in …

Sintesi di nuovi derivati 1,2,5-ossadiazolici della Rebeccamicina ad attività antitumorale.

Acrylamide catalytically inhibits topoisomerase II in V79 cells.

2010

The vinyl monomer acrylamide is characterized by the presence of an alpha,beta-unsaturated carbonyl group that makes it reactive towards thiol, hydroxyl or amino groups and towards the nucleophilic centers in DNA. The ability of acrylamide to chemically modify protein thiols has prompted us to consider topoisomerase II as one possible target of acrylamide, since agents targeting protein sulfhydryl groups act as either catalytic inhibitors or poisons of topoisomerase II. Nuclear extracts from V79 Chinese hamster cells incubated with acrylamide reduced topoisomerase II activity as inferred by an inability to convert kinetoplast DNA to the decatenated form. Nuclear extracts incubated with acry…

Clarkson-McCarthy inequalities with unitary and isometry orbits

2020

Abstract A refinement of a trace inequality of McCarthy establishing the uniform convexity of the Schatten p-classes for p > 2 is proved: if A , B are two n-by-n matrices, then there exists some pair of n-by-n unitary matrices U , V such that U | A + B 2 | p U ⁎ + V | A − B 2 | p V ⁎ ≤ | A | p + | B | p 2 . A similar statement holds for compact Hilbert space operators. Another improvement of McCarthy's inequality is given via the new operator parallelogramm law, | A + B | 2 ⊕ | A − B | 2 = U 0 ( | A | 2 + | B | 2 ) U 0 ⁎ + V 0 ( | A | 2 + | B | 2 ) V 0 ⁎ for some pair of 2n-by-n isometry matrices U 0 , V 0 .

Utilisation of natural carotenoids from Momordica cochinchinensis (gac) as health compounds : extraction and bioactvity depending on the origin and o…

2014

The aril of Momordica cochinchinensis (gac), plant from the Cucurbitaceae family, is the richest source of lycopene and β-carotene, which are a strong antioxidant and a pro-vitamin A, respectively, interesting for health-complements. First, a process of soft extraction-fractionation was developed for extracting effectively the natural carotenoids from gac without loss of their original quality. Then, the lycopene and β-carotene extracted from gac were analyzed and characterized. At least 95% of the extracts were composed of the all-trans isomer. They were not degraded during the heat-treatment mimicking formulation processing. Their thermal stereo-mutation was evaluated. Lycopene is more an…

Excitability regulation in the dorsomedial prefrontal cortex during sustained instructed fear responses: a TMS-EEG study

2018

AbstractBackgroundThreat detection is essential for protecting individuals from precarious situations. Early studies suggested a network of amygdala, limbic regions and dorsomedial prefrontal cortex (dmPFC) involved in fear processing. Excitability regulation in the dmPFC might be crucial for physiological fear processing, while an abnormal excitability pattern could lead to mental illness. Non-invasive paradigms to measure excitability regulation during fear processing in humans are missing.MethodsWe adapted an experimental approach of excitability characterization using electroencephalography (EEG) recordings and transcranial magnetic stimulation (TMS) over the dmPFC during an instructed …