Search results for " EXPRESSION"
showing 10 items of 4731 documents
Melanoma cells release extracellular vesicles which contain RNA-binding proteins able to bind the mRNA encoding histone H1°
2015
Extracellular vesicles (EVs) are produced by most prokaryotic and eukaryotic cells; tumour cells, however, release much higher amounts of EVs, which contain cancer-specific proteins and RNAs. Molecules carried by EVs are captured by surrounding cells, which then undergo profound phenotypic modifications. G26/24 oligodendroglioma cells release, for example, EVs containing FasL and TRAIL, which induce apoptosis in rat cortical neurons and astrocytes in culture. By metabolic labelling of cells, EV-mediated horizontal transfer of radioactive proteins was clearly demonstrated. Among the proteins present in EVs produced by oligodendroglioma cells, extracellular matrix remodelling proteases, and t…
RNA as a carrier of epigenetic information
2017
Both prokaryotic and eukaryotic cells release into the extracellular matrix membrane-bound structures of different sizes, origin and composition, collectively called extracellular vesicles (EVs) [1]. Tumor cells, in particular, use EVs to transfer both nucleic acids and proteins to the surrounding normal cells, thus inducing in them transformed behaviours or killing them. G26/24 oligodendroglioma cells, for example, transfer by EVs pro-apoptotic proteins, such as TRAIL and Fas-Ligand [2], extracellular matrix remodelling proteases (such as ADAMTS) [3], and even the H1.0 histone protein [4]. Another tumour cell line, with a different tissue origin (A375 melanoma cells) releases into the medi…
Extracellular vesicles released from melanoma cells contain H1° mRNA-binding proteins, one of which is (probably) MYEF2.
2015
Release of extracellular vesicles (EVs) is a process conserved from prokaryotes to eucaryotes. Although EVs are produced from both normal and cancer cells, malignant cells release a much higher amount of EVs, which contain tumour-specific proteins and RNAs. We previously found that G26/24 oligodendroglioma cells shed EVs that contain the pro-apoptotic factors FasL and TRAIL and are able to inhibit neurite outgrowth, and induce apoptosis in about 75% of rat cortical neurons [1] and 40% of astrocytes [2] in culture. By labelling proteins synthesized in one cell type, we also demonstrated EV-mediated horizontal transfer of proteins among brain cells. Interestingly, G2624 release, via EVs, extr…
Functional antagonism between histone H3K4 demethylases in vivo
2011
Dynamic regulation of histone modifications is critical during development, and aberrant activity of chromatin-modifying enzymes has been associated with diseases such as cancer. Histone demethylases have been shown to play a key role in eukaryotic gene transcription; however, little is known about how their activities are coordinated in vivo to regulate specific biological processes. In Drosophila, two enzymes, dLsd1 (Drosophila ortholog of lysine-specific demethylase 1) and Lid (little imaginal discs), demethylate histone H3 at Lys 4 (H3K4), a residue whose methylation is associated with actively transcribed genes. Our studies show that compound mutation of Lid and dLsd1 results in increa…
Metallothionein genes in sea urchin embryos and their induction by cadmium
2012
Metallothioneins (MTs) are proteins that play a major role in metal homeostasis and as a reservoir. The MT gene/protein systems of sea urchins are an invaluable model for the study of gene expression regulation and MT isoform-specific functionality of these proteins. We isolated five paralogous MT isogenes and we studied their expression in the sea urchin embryo Paracentrotus lividus. The Cadmium-dependent transcriptional activation of the five isogenes was assessed using quantitative Real Time PCR. Two of the five P. lividus MT (MT-7 and MT-8) isogenes appeared to be constitutively expressed and upregulated upon cadmium treatment. Three isogenes (MT-4/MT-6) are not transcribed in control e…
Dorsal/Ventral asymmetric expression of nodal in the early sea urchin embryo relies on specific suppression in dorsal cells by the Hbox12 homeodomain…
2014
Dorsal/Ventral (DV) polarization of the sea urchin embryo is directed by a Nodal-expressing signaling centre located on the ventral side. The initial breaking of the symmetry and positioning of the organizer are unclear. We show that, in Paracentrotus lividus embryos, the Hbox12 homeodomaincontaining repressor is expressed on the opposite side and precedes the onset of nodal transcription. Hbox12 misexpression provokes DV abnormalities, attenuating nodal and nodal-dependent gene transcription. Reciprocally, clonal hbox12 loss-of-function imposed by blastomere transplantation or gene transfer assays disrupts DV polarization and allows ectopic expression of nodal. Remarkably, the localized kn…
The sea urchin histone H2A enhancer-binding protein MBF-1 is needed for maximal expression also for the H3 gene, while is buffered by the sns5 insula…
2009
Enhancers are DNA elements which increase the transcription of associated gene in a position and distance independent manner relative to the transcription initiation site. Molecular mechanisms must operate to direct enhancers to specific promoters in complex genetic loci. The sea urchin a-histone genes are organized in several hundred tandem repeated units, each containing one copy of the five histone genes in the order 5’-H4-H2B-H3-H2A-H1-3’. Transcription is limited to the early cleavage and reaches its maximum at morula stage. After hatching these genes are repressed and maintained in the silenced state for whole life cycle of the animal. In Paracentrotus lividus, the MBF-1 activator bin…
Combined effect of cadmium and sulfonamides on sea urchin development
2013
Echinoderms play a key role in the maintenance of the integrity of the ecosystem where they live. They are constantly exposed to pollutants, particularly in their early planktonic life stages. Sulfamethoxazole with trimethoprim (TMP/SMX) is a fixed antibiotic combination whose concentration is significantly increasing in the coastal waters due to human medicine and also intensive husbandry and aquaculture activities. Previously, we studied the defense strategies activated by P. lividus embryos in response to sublethal doses of CdCl2. Although toxic effects of cadmium on embryo development are not morphologically detectable before 24 hours of exposure, we found upregulation in mRNAs related …
Downregulation of myogenic microRNAs in sub-chronic but not in sub-acute model of daunorubicin-induced cardiomyopathy
2016
Cardiac muscle-related microRNAs play important roles in cardiac development and disease by translational silencing of mRNAs, the dominant mechanism of microRNA action. To test whether they could be involved in daunorubicin-associated cardiomyopathy (DACM), we determined expression patterns of myomiRs in two distinct models of DACM. We used 10â12 weeks old male Wistar rats. In the sub-acute model, rats were administered with six doses of daunorubicin (DAU-A, 3Â mg/kg, i.p., every 48Â h). Rats were sacrificed two days after the last dose. In the sub-chronic model, anaesthetized rats were administered a single dose of daunorubicin (15Â mg/kg, i.v., DAU-C). Age-matched controls (CON) receive…
Matrix metalloproteinase-2 matrix metalloproteinase-9 and inducible nitric oxide synthase in oral leukoplakia: Immunohistochemistry and RT-PCR analys…
2008
Oral leukoplakia is the most common and potentially malignant disorder of the oral mucosa. The definition of leukoplakia given by the World Health Organization is "a white plaque that cannot be characterized either from a clinical or from a histopathological point of view", thus the diagnosis of leukoplakia is based on the exclusion of other lesions of the oral mucosa. We believe it is necessary to identify molecular and immunohistochemical parameters that can contribute to discriminating between the different leukoplakia clinical subtypes coded by the epidemiology. In the present work we show the preliminary results of this research project. We investigated the expression of matrix metallo…