Search results for " EXPRESSION"
showing 10 items of 4731 documents
Peripheral T-cell lymphoma classification: the matter of cellular derivation.
2011
Peripheral T-cell lymphomas (PTCLs) represent approximately 12% of all non-Hodgkin's lymphomas in Western countries. They are quite heterogeneous as far as morphology and phenotype are concerned. Furthermore, until now, PTCLs could not be referred to specific normal counterparts, in contrast to B-cell-derived non-Hodgkin's lymphomas. In particular, in the last edition of the WHO classification of Tumors of the Hematopoietic and Lymphoid Tissues, for the majority of nodal PTCLs (including the not otherwise specified type and anaplastic large-cell lymphoma), the postulated cell of origin remained undefined. However, in the last few years, high-throughput genomic techniques, especially gene-ex…
Liver-primed memory T cells generated under noninflammatory conditions provide anti-infectious immunity.
2013
SummaryDevelopment of CD8+ T cell (CTL) immunity or tolerance is linked to the conditions during T cell priming. Dendritic cells (DCs) matured during inflammation generate effector/memory T cells, whereas immature DCs cause T cell deletion/anergy. We identify a third outcome of T cell priming in absence of inflammation enabled by cross-presenting liver sinusoidal endothelial cells. Such priming generated memory T cells that were spared from deletion by immature DCs. Similar to central memory T cells, liver-primed T cells differentiated into effector CTLs upon antigen re-encounter on matured DCs even after prolonged absence of antigen. Their reactivation required combinatorial signaling thro…
Diacylglycerol-containing oleic acid induces increases in [Ca(2+)](i) via TRPC3/6 channels in human T-cells.
2011
Though most of the studies have focused on the effects of free fatty acids on T-cell activation, fatty acids incorporated into plasma membrane phospholipids may also affect cell signaling via diacylglycerol (DAG), generally produced by phospholipid hydrolysis. In the present study, we have synthesized a DAG-containing oleic acid and studied its implication in the modulation of calcium signaling in human Jurkat T-cells. 1-palmitoyl-2-oleoyl-sn-glycerol (POG) induced a dose-dependent increase in [Ca(2+)](i). This effect was due to the presence of oleic acid at the sn-2 position as no differences were observed between POG and 1-stearoly-2-oleoyl-sn-glycerol (SOG). However, the substitution of …
Tolerance without clonal expansion: self-antigen-expressing B cells program self-reactive T cells for future deletion.
2008
Abstract B cells have been shown in various animal models to induce immunological tolerance leading to reduced immune responses and protection from autoimmunity. We show that interaction of B cells with naive T cells results in T cell triggering accompanied by the expression of negative costimulatory molecules such as PD-1, CTLA-4, B and T lymphocyte attenuator, and CD5. Following interaction with B cells, T cells were not induced to proliferate, in a process that was dependent on their expression of PD-1 and CTLA-4, but not CD5. In contrast, the T cells became sensitive to Ag-induced cell death. Our results demonstrate that B cells participate in the homeostasis of the immune system by abl…
Recombinant expression, in vitro refolding, and biophysical characterization of the N-terminal domain of T1R3 taste receptor
2012
Facteur d'impact (5 ans) : 1,617Notoriété à 2 ans : Acceptable (biochem.res.methods); The sweet taste receptor is a heterodimeric receptor composed of the T1R2 and T1R3 subunits, while T1R1 and T1R3 assemble to form the umami taste receptor. T1R receptors belong to the family of class C G-protein coupled receptors (GPCRs). In addition to a transmembrane heptahelical domain, class C GPCRs have a large extracellular N-terminal domain (NTD), which is the primary ligand-binding site. The T1R2 and T1R1 subunits have been shown to be responsible for ligand binding, via their NTDs. However, little is known about the contribution of T1R3-NTD to receptor functions. To enable biophysical characteriza…
Cloning and functional analyses of the mouse tapasin promoter
2003
The expression of tapasin is critical for an optimized MHC class I assembly and stable MHC class I surface expression. Thus, impaired MHC class I antigen expression of tumors can be attributable to tapasin downregulation. In order to understand the molecular mechanisms of deficient tapasin expression, the mouse tapasin promoter region and its 5'-flanking sequences were characterized. The mouse tapasin promoter lacks the TATA box and its transcription is initiated at multiple sites within a 51-nucleotide stretch. Sequence analyses revealed transcription factor binding motifs for NF-kappaB, GATA, E2F, p300, AP1, SP1 and IRF-1/2. Detailed analysis of deletion mutants and elimination of transcr…
In silico characterization of an Iroquois family-related homeodomain protein.
2005
Homeobox genes have been demonstrated to play important roles during cancer differentiation and embryonic development. The subset of Iroquois-related homeobox genes (IRXs) have furthermore been. demonstrated to be involved in several embryonic developmental processes such as patterning of the anterior-posterior and dorso-ventral axis, as well as specific regions of the central nervous system, and differentiation of the otic vesicle, branchial epithelium, and limbs. We have characterized a novel homeodomain protein and corresponding gene by means of computational biology. Since the protein sequence displayed high similarity to the human IRX proteins, the newly identified homeodomain protein …
Common gene expression strategies revealed by genome-wide analysis in yeast
2007
A comprehensive analysis of six variables characterizing gene expression in yeast, including transcription and translation, mRNA and protein amounts, reveals a general tendency for levels of mRNA and protein to be harmonized, and for functionally related genes to have similar values for these variables.
HNRNPR Variants that Impair Homeobox Gene Expression Drive Developmental Disorders in Humans
2019
The heterogeneous nuclear ribonucleoprotein (HNRNP) genes code for a set of RNA-binding proteins that function primarily in the spliceosome C complex. Pathogenic variants in these genes can drive neurodegeneration, through a mechanism involving excessive stress-granule formation, or developmental defects, through mechanisms that are not known. Here, we report four unrelated individuals who have truncating or missense variants in the same C-terminal region of hnRNPR and who have multisystem developmental defects including abnormalities of the brain and skeleton, dysmorphic facies, brachydactyly, seizures, and hypoplastic external genitalia. We further identified in the literature a fifth ind…
The Saccharomyces cerevisiae flavodoxin-like proteins Ycp4 and Rfs1 play a role in stress response and in the regulation of genes related to metaboli…
2011
SPI1 is a gene whose expression responds to many environmental stimuli, including entry into stationary phase. We have performed a screening to identify genes that activate SPI1 promoter when overexpressed. The phosphatidylinositol- 4-phosphate 5-kinase gene MSS4 was identified as a positive activator of SPI1. Another SPI1 transcriptional regulator isolated was the flavodoxin-like gene YCP4. YCP4 and its homolog RFS1 regulate the expression of many genes during the late stages of growth. The double deletion mutant in YCP4 and its homolog RFS1 has an impact on gene expression related to metabolism by increasing the expression of genes involved in hexose transport and glycolysis, and decreasi…