Search results for "EXPRESSION"
showing 10 items of 5168 documents
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…
Human umbilical cord expresses several vasoactive peptides involved in the local regulation of vascular tone: protein and gene expression of Orphanin…
2011
Full-term human umbilical cord contains three blood vessels: two arteries coiled around a vein and surrounded by Wharton’s jelly, a mucous tissue with few mesenchymal stromal cells and abundant extracellular matrix. Umbilical vessels lack innervations, thus endothelial cells must play a role in the control of blood flow. The aim of this study was to investigate in human umbilical cord the expression of five peptides that could be involved in the regulation of vascular tone: Orphanin FQ, Oxytocin, Atrial Natriuretic Peptide (ANP), endothelial Nitric Oxide Synthase (eNOS) and inducible Nitric Oxide Synthase (iNOS). The expression of these molecules in full-term human umbilical cord …
Expression of Cyclooxygenase-1 and Cyclooxygenase-2 in normal and pathological human oral mucosa
2011
Abstract: Cyclooxigenase (COX) is the rate-limiting enzyme for the conversion of arachidonic acid (AA) to prostaglandins (PGs). Two isoforms of COX have been identified: COX-1 is constitutively expressed in many cells and is involved in cell homeostasis, angiogenesis and cell-cell signalling; COX-2 is not expressed in normal condition however it is strongly expressed in inflammation. The oral cavity is costantly exposed to physical and chemical trauma that could lead to mucosal reactions such as hyperplasia, dysplasia and cancer. Early diagnosis is the most important issue to address for a positive outcome of oral cancer; therefore it would be useful to identify molecular markers whose expr…
Immunohistochemical and transcriptional expression of matrix metalloproteinases in full-term human umbilical cord and Human Umbilical Vein Endothelia…
2010
Matrix metalloproteinases (MMPs) are extracellular zinc-dependent endopeptidases involved in the degradation and remodelling of extracellular matrix in physiological and pathological processes. MMPs also have a role on cell proliferation, migration, differentiation, angiogenesis and apoptosis. Umbilical cord is a special organ subjected to many changes during pre-natal life and whose cells can maintain a certain degree of plasticity also in post-natal period; for example recently they have been used as a source of stem cells. In this work we investigated the expression of MMPs in human umbilical cord and Human Umbilical Vein Endothelial Cells (HUVEC) though immunohistochemistry, RT-PCR and …
Identification of a prognostic gene signature associated with MBP-1 expression in ErbB2-negative breast carcinomas
2014
The ENO1 transcript, which encodes the glycolitic enzyme alpha-enolase, can be translated into a shorter nuclear protein called Myc-promoter Binding Protein-1 (MBP-1) by using an alternative translation start site. MBP-1 acts as a negative regulator of c-Myc, ErbB2 and Cox2 genes (1). Several evidences indicate that MBP-1 acts as a tumor suppressor in breast carcinoma and prostate cancer and its expression results in a reduced invasive ability (2). In our previous studies, we showed that MBP-1 is expressed and easily detectable in normal breast epithelial cells, but a loss of expression occurs in most primary invasive ductal carcinomas (IDC) of the breast. Furthermore, in these tumors MBP-1…