Alternative splicing of pre-mRNA is a prominent mechanism to generate protein diversity, yet its regulation is poorly understood. Here, we demonstrate a direct role for histone modifications in alternative splicing. We find distinctive histone modification signatures which correlate with splicing outcome in a set of human genes. Modulation of histone modifications causes splice site switching. The mechanism for histone-mediated splice site selection involves a histone mark which is read by a chromatin protein, which in turn recruits a splicing regulator. These results outline an adaptor system for reading of histone marks by the pre-mRNA splicing machinery. Overall design: To obtain an estimate of how many PTB-dependent alternative splicing events are regulated by SET2/MRG15-mediated recruitment of PTB, we carried out a genomewide comparative analysis of alternative splicing in hMSC cells depleted of either SETD2, MRG15 or PTB using specific siRNAs, or mock-depleted using a control siRNA.
Regulation of alternative splicing by histone modifications.
No sample metadata fields
View SamplesThis study is part of previous epidemiologic project, including a population-based survey (Sao Paulo Ageing & Health study (SPAH Study). The data from this study was collected between 2015 to 2016 and involved elderly women (ages ≥65 yeas) living in the Butanta district, Sao Paulo. The purpose of the study was identification of association between transcriptome and the osteo metabolism diseases phenotype, like osteoporosis, vertebral fracture and coronary calcification.
Overexpression of SNTG2, TRAF3IP2, and ITGA6 transcripts is associated with osteoporotic vertebral fracture in elderly women from community.
Sex, Age
View SamplesThe anticarcinogenic activity of hydroxytyrosyl ethyl ether (HTy-Et) compared to its precursor hydroxytyrosol (HTy) has been studied in human Caco-2 colon adenocarcinoma cells.
Hydroxytyrosyl ethyl ether exhibits stronger intestinal anticarcinogenic potency and effects on transcript profiles compared to hydroxytyrosol.
Specimen part, Disease, Disease stage, Cell line
View SamplesPlant drought stress response and resistance are complex biological processes that merit systems-level analyses to dissect drought stress encountered by crops in the field. We have used gene expression profiling of Arabidopsis plants subjected to a controlled, sublethal, moderate drought (mDr) treatment to characterize early and late response to drought. We have also compared these profiles to those from plants treated with soil water deficit (progressive) drought (pDr) to reveal acclimation responses in plants.
Molecular and physiological analysis of drought stress in Arabidopsis reveals early responses leading to acclimation in plant growth.
Specimen part, Treatment
View SamplesInadequate extracellular conditions can adversely affect the environment of the ER and impinge on the maturation of nascent proteins. The resultant accumulation of unfolded proteins activates a signal transduction pathway, known as the unfolded protein response, which serves primarily to protect the cell during stress and helps restore homeostasis to the ER. Microarray analysis of the unfolded protein response in a human medulloblastoma cell line treated with thapsigargin revealed that, in addition to known targets, a large number of proangiogenic factors were up-regulated. Real-time PCR analyses confirmed that four of these factors, VEGF, FGF2, angiogenin and IL-8, were transcriptionally up-regulated in multiple cell lines by various ER stress inducers. Our studies on VEGF regulation revealed that XBP-1(S), a UPR-inducible transcription factor, bound to two regions on the VEGF promoter, and analysis of XBP-1 null mouse embryonic fibroblasts revealed that it contributes to VEGF expression in response to ER stress. ATF4, another UPR-inducible transcription factor, also binds to the VEGF gene, although its contribution to VEGF transcription appeared to be fairly modest. We also found that VEGF mRNA stability is increased in response to UPR activation, via activation of the AMP and p38MAP kinases, demonstrating that increased mRNA levels occur at two regulatory points. In keeping with the mRNA levels, we found that VEGF protein is secreted at levels as high as or higher than that achieved in response to hypoxia. Our results indicate that the UPR plays a significant role in inducing positive regulators of angiogenesis. It also regulates VEGF expression at multiple levels and is likely to have widespread implications for promoting angiogenesis in response to normal physiological cues as well as in pathological conditions like cancer.
Transcriptional and post-transcriptional regulation of proangiogenic factors by the unfolded protein response.
Treatment, Time
View SamplesRed light can affect a variety of responses in Arabidopsis. We characterize the early gene expression patterns of seedlings exposed to 1 hour of red light using a small sized sample of 5, 7-day-old seedlings and also performed dark controls.
Extraction and labeling methods for microarrays using small amounts of plant tissue.
No sample metadata fields
View SamplesThe observation that Tcf3 (MGI name: Tcf7l1) bound the same genes as core stem cell transcription factors, Oct4 (MGI name:Pou5f1), Sox2 and Nanog, revealed a potentially important aspect of the poorly understood mechanism whereby Wnts stimulate self renewal of pluripotent mouse embryonic stem (ES) cells. Although the conventional view of Tcf proteins as the -catenin-binding effectors of Wnt signaling suggested Tcf3 should activate target genes in response to Wnts, here we show that Wnt3a and Tcf3 effectively antagonize each others effects on gene expression. Genetic ablation of Tcf3 caused similar effects as treating cells with recombinant Wnt3a.
Opposing effects of Tcf3 and Tcf1 control Wnt stimulation of embryonic stem cell self-renewal.
Treatment
View SamplesThe objective of this study was to identify transcriptional changes differentially regulated by GDF11 stimulation compared to TGFB1
Tumor-Suppressor Inactivation of GDF11 Occurs by Precursor Sequestration in Triple-Negative Breast Cancer.
Specimen part
View SamplesSIRT1 deacetylase functions in a variety of cells and tissues to mitigate age- and disease-induced damages. However, it remains unknown if SIRT1 also acts to prevent pathological changes that accrue in motor units, and specifically alpha-motor neurons, with advancing age and during the progression of amyotrophic lateral sclerosis (ALS). Here, we show that SIRT1 expression decreases in the spinal cord of wild type mice with advancing age. Using mouse models that overexpress or inactivate SIRT1 in motor neurons, we discovered that SIRT1 prevents age-related degeneration of motor neurons' presynaptic sites at neuromuscular junctions (NMJs). We also found that increasing SIRT1 in motor neurons delays degeneration of presynaptic sites at NMJs and extends the lifespan of SOD1G93A mice. Thus, SIRT1 has a similar effect on aging and ALS-affected motor neurons, two conditions in which a remarkable number of transcripts are similarly altered in the spinal cord. These include genes involved in inflammatory and immune responses and genes with known function at synapses. These findings show that SIRT1 functions to mitigate pathological changes induced by aging and ALS, two conditions with a surprising degree of overlap in the spinal cord. Overall design: Eight replicates spinal cords from mice aged 18-24 months, eight replicates of spinal cords from mice aged 3-4 months, 3 replicates of spinal cords from ALS symptomatic mice aged 5-6 months and 3 replicates of spinal cords from wt controls aged 5-6 months.
SIRT1 deacetylase in aging-induced neuromuscular degeneration and amyotrophic lateral sclerosis.
Cell line, Subject
View SamplesIn order to establish a list of candidate direct COUP-TFI gene targets in the inner ear, we analyzed the differential gene expression profiles of the wild-type and the COUP-TFI/ P0 inner ears.
Genome-wide analysis of binding sites and direct target genes of the orphan nuclear receptor NR2F1/COUP-TFI.
Specimen part
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