Processing of Immunoglobulin heavy chain (IgH) mRNA is a paradigm for competition between splicing and polyadenylation. In plasma cells pre-mRNA is polyadenylated mainly at the promoter-proximal secretory site while B-cells utilize a cryptic 5 splice site in the last secretory-specific exon; these are mutually exclusive events for all IgH pre-mRNAs. Transcription elongation factor ELL2, more abundant in plasma cells relative to B-cells, was down-modulated by overexpression of heterogenous ribonucleoprotein F, a condition which reduced production of secretory IgH mRNA. Transfection of B-cells with ELL2 and the IgH reporter showed an accelerated use of the secretory poly(A) site, positioned in competition with the splice to M1; a small interfering RNA to ELL2 reduced expression of IgH secretory mRNA. Co-transcription factors ELL1 and PC4 were ineffective at driving secretory-poly(A) site use. ELL2 had little effect on poly(A) site choice with reporters containing tandem-linked poly(A) sites. Shorter forms of ELL2 protein result from both internal initiation at M186 and protein processing. An alternative splicing reporter driven by IgH or non-Ig promoters revealed that ELL2 and its M186 initiated form were able to accelerate exon skipping. Therefore, ELL2 influences IgH pre-mRNA processing through facilitating skipping of the alternative splice to the membrane form.
Transcription elongation factor ELL2 directs immunoglobulin secretion in plasma cells by stimulating altered RNA processing.
No sample metadata fields
View SamplesExpression profiles of wild type migratory border cells (WTBC), non-migrating slbo mutant border cells (slboBC) and non-migrating follicle cells (FC)
Systematic analysis of the transcriptional switch inducing migration of border cells.
Sex, Specimen part
View SamplesArabidopsis plants were treated either with mock or MSB (0.2 mM of Menadione sodium bisulphite). <br></br>Tissue was sampled after 3, 6 and 24 hours.
Molecular analysis of menadione-induced resistance against biotic stress in Arabidopsis.
Age, Specimen part, Compound, Time
View SamplesSenescence is a cellular phenotype present in health and disease, characterized by a stable cell cycle arrest and an inflammatory response, denominated senescence-associated secretory phenotype (SASP). The SASP is important in influencing the behaviour of neighbouring cells and altering the microenvironment; yet, this role has been mainly attributed to soluble factors. Here, we show that both the soluble factors in addition to small extracellular vesicles (sEV) are capable of transmitting paracrine senescence to nearby cells. Analysis of individual cells internalizing sEV, using a Cre-reporter system, show a positive correlation between sEV uptake and senescence activation. Interestingly, we find an increase in the number of multivesicular bodies during senescence in vivo. sEV protein characterization by mass spectrometry (MS) followed by a functional siRNA screen identify the Interferon Induced Transmembrane Protein 3 (IFITM3) as partially responsible for transmitting senescence to normal cells. Altogether, we found that sEV contribute to paracrine senescence. Overall design: SASP related mRNA transcripts in HFFF2 treated with sEV from iRAS cells in comparison with HFFF2 treated with sEV from iC cells
Small Extracellular Vesicles Are Key Regulators of Non-cell Autonomous Intercellular Communication in Senescence via the Interferon Protein IFITM3.
Disease, Subject
View SamplesWe describe here a male infant with a 100 kb de novo Xq28 deletion encompassing parts of the TMEM187 and MECP2 protein-coding genes and the IRAK1 protein-coding gene, as well as the MIR3202-1, MIR3202-2, and MIR718 RNA-coding genes. We analyzed the impact of human IRAK-1 deficiency on a genome-wide gene expression in human fibroblasts in response to TLR2/6, TLR4 agonists as well as to IL-1 and TNF-, using primary fibroblasts from healthy controls and IRAK-4-, MyD88- and MECP2-deficient patients for comparison.
Inherited human IRAK-1 deficiency selectively impairs TLR signaling in fibroblasts.
No sample metadata fields
View SamplesRNA was labeled and hybridized to ATH1 arrays.
Arabidopsis RETINOBLASTOMA-RELATED is required for stem cell maintenance, cell differentiation, and lateral organ production.
Specimen part, Compound
View SamplesNeurodegenerative brain disorders become more common in the aged. Most of these disorders are associated with or caused by selective death of certain neuronal subpopulations. The mechanisms underlying the differential vulnerability of certain neuronal populations are still largely unexplored and few neuroprotective treatments are available to date. Elucidation of these mechanisms may lead to a greater understanding of the pathogenesis and treatment of neurodegenerative diseases. Moreover, preconditioning by a short seizure confers neuroprotection following a subsequent prolonged seizure. Our goal is to identify pathways that confer vulnerability and resistance to neurotoxic conditions by comparing the basal and preconditioned gene expression profiles of three differentially vulnerable hippocampal neuron populations.
Gene expression changes after seizure preconditioning in the three major hippocampal cell layers.
No sample metadata fields
View SamplesPlant reproduction depends on the concerted activation of many genes to assure the correct communication between pollen and pistil. Here we queried the whole transcriptome of Arabidopsis thaliana in order to identify genes with specific reproductive functions.
Whole genome analysis of gene expression reveals coordinated activation of signaling and metabolic pathways during pollen-pistil interactions in Arabidopsis.
Specimen part
View SamplesWe have identified the causal genes, which is MYB36, of ionome mutants.
The MYB36 transcription factor orchestrates Casparian strip formation.
Specimen part
View SamplesDespite their different origin and function, both pollen tubes and root hairs share the same sort of apical growth mechanism, i.e., the spatially focused cell expansion at the very apex. Ion fluxes, membrane trafficking, the actin cytoskeleton and their interconnection via signaling networks have been identified as fundamental processes underlying this kind of growth. Several molecules involved in apical growth have been identified, but the genetic basis is far from being fully characterized. We have used Affymetrix Arabidopsis ATH1 GeneChips to obtain the expression profiles of isolated Arabidopsis root hairs. A comparison with the expression profile of flow-sorted pollen grains reveals an overlap in the expression of 4989 genes, which corresponds to 42% of the root hair transcriptome and 76% of the pollen transcriptome, respectively. Our comparison with transcriptional profiles of vegetative tissues by principal component analysis and hierarchical clustering shows a clear separation of these samples comprised of cell types with diffuse growth from the two cell types with apical growth. 277 genes are enriched and 49 selectively expressed, respectively, in root hairs and pollen. From this set of genes emerges an apical growth signature containing novel candidate genes for apical growth determination.
Transcriptional profiling of Arabidopsis root hairs and pollen defines an apical cell growth signature.
Specimen part
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