Mammalian transcriptomes display complex circadian rhythms with multiple phases of gene expression that cannot be accounted for by current models of the molecular clock. We have determined the underlyingmechanisms by measuring nascent RNA transcription around the clock in mouse liver. Unbiased examination of eRNAs that cluster in specific circadian phasesidentified functional enhancers driven by distinct transcription factors (TFs). We further identify on a global scale the components of the TF cistromes that function to orchestrate circadian gene expression. Integrated genomicanalysesalso revealed novel mechanisms by which a single circadian factor controls opposing transcriptional phases. These findings shed new light on the diversity and specificity of TF function in the generation of multiple phases of circadian gene transcription in a mammalian organ.
Circadian enhancers coordinate multiple phases of rhythmic gene transcription in vivo.
Sex, Time
View SamplesWhile long noncoding RNAs (lncRNAs) and mRNAs share similar biogenesis pathways, these two transcript classes differ in many regards. LncRNAs are less conserved, less abundant, and more tissue specific than mRNAs, implying that our understanding of lncRNA transcriptional regulation is incomplete. Here, we perform an in depth characterization of numerous factors contributing to this regulation. We find that lncRNA promoters contain fewer transcription factor binding sites than do those of mRNAs, with some notable exceptions. Surprisingly, we find that H3K9me3 –typically associated with transcriptional repression–is enriched at active lncRNA loci. However, the most discriminant differences between lncRNAs and mRNAs involve splicing: only half of lncRNAs are efficiently spliced, which can be partially attributed to defects in lncRNA splicing signals and diminished U2AF65 binding. These attributes are conserved between humans and mice. Finally, we find that certain transcriptional properties are enriched in known, functionally characterized lncRNAs, demonstrating that our multidimensional analysis might discern lncRNAs that are likely to be functional Overall design: Examination of RNA abundance in two cell lines (K562 and Hues9) and 5 time points after actinomycin D treatment. Three replicates per time point and cell type.
Chromatin environment, transcriptional regulation, and splicing distinguish lincRNAs and mRNAs.
Cell line, Subject, Time
View SamplesBackground: The use of electrical pulses to enhance uptake of molecules into living cells have been used for decades. This technique, often referred to as electroporation, has become an increasingly popular method to enhance in vivo DNA delivery for both gene. therapy applications as well as for delivery of vaccines against both infectious diseases and cancer. In vivo electrovaccination is currently being investigated in several clinical trials, including DNA delivery to healthy volunteers. However, the mode of action at molecular level is not yet fully understood.
Skin electroporation: effects on transgene expression, DNA persistence and local tissue environment.
Specimen part
View SamplesApoptosis is deregulated in most, if not all, cancers, including hematological malignancies. In this study, we wanted to test whether primary acute myeloid leukemia (AML) samples are sensitive for inhibitor of apoptosis (IAP) protein antagonist treatment in vitro, and which AML subgroup might profit most from such a novel therapeutic strategy. We treated diagnostic samples of 67 adult AML patients with either cytarabine (ara-C) or IAP antagonist BV6 and correlated sensitivity with clinical, cytogenetic and molecular markers, and expression levels of selected genes involved in apoptosis. Primary AML samples showed differential sensitivity to treatment with either ara-C (40% sensitive, 17% intermediate, 43% resistant) or BV6 (51% sensitive, 21% intermediate, 28% resistant). Notably, 69% of ara-C resistant samples showed a good to fair response to IAP inhibition. Furthermore, combination treatment of ara-C with BV6 showed additive effects in most samples. Differences in sensitivity to IAP antagonist treatment correlated with significantly elevated expression levels of TNF and lower levels of XIAP in BV6 sensitive samples, as well as with NPM1 mutations. Gene expression profiling pointed to apoptosis-related pathways, which were specifically induced by IAP inhibition in sensitive samples. Thus, our results suggest IAP inhibition as a potential novel therapeutic option in AML.
Targeting inhibitor of apoptosis proteins by Smac mimetic elicits cell death in poor prognostic subgroups of chronic lymphocytic leukemia.
Sex, Age, Treatment
View SamplesInhibitor of apoptosis (IAP) proteins are expressed at high levels in CLL cells and may contribute to evasion of cell death leading to poor therapeutic outcome. Of note, prognostic unfavourable cases with e.g. non-mutated VH-status and TP53 mutation responded significantly better to BV6 than samples with unknown or favourable prognosis e.g. 13q deletion. The majority of cases with 17p deletion (10/12) and Fludarabine refractory cases were sensitive to BV6, indicating that BV6 acts independently of the p53 pathway. Importantly, BV6 dose-dependently induced cell death in 28 of 51 (54%) investigated patient samples while B cells from healthy donors were largely unaffected. BV6 also triggered cell death under survival conditions mimicking the microenvironment e.g. by adding CD40 ligand or in conditioned medium. Gene expression profiling identified cell death- and NF-kB-signaling among the top pathways regulated by BV6. This was confirmed by data showing that BV6 causes degradation of cIAP1 and cIAP2 and NF-kB pathway activation. BV6 induced cell death depended on production of reactive oxygen species, since addition of ROS scavengers significantly rescued BV6-triggerd cell death. In contrast, BV6 induced cell death independently of caspase activity, RIP1 activity or TNF-alpha, since zVAD.fmk, necrostatin-1 or TNF-alpha-blocking antibody Enbrel failed to protect against cell death. Of note, transcripts of ROS regulatory proteins were modulated by BV6. Thus, these data have important implications for developing new therapeutic strategies to overcome cell death resistance in CLL especially in poor prognostic subgroups.
Targeting inhibitor of apoptosis proteins by Smac mimetic elicits cell death in poor prognostic subgroups of chronic lymphocytic leukemia.
Sex, Age, Treatment
View SamplesBulked segregant analysis (BSA) is an efficient method to rapidly and efficiently map genes responsible for mutant phenotypes. This procedure, however, requires access to quantitative genetic markers that are polymorphic in the mapping population. We have developed a modification of BSA (BSR-Seq) that makes use of RNA-Seq reads to efficiently map genes even in populations for which no polymorphic markers have been previously identified. Because of the digital nature of next-generation sequencing (NGS) data, it is possible to conduct de novo SNP discovery and quantitatively genotype BSA samples using the same RNA-Seq data. In addition, analysis of the RNA-Seq data provides information on the effects of the mutant on global patterns of gene expression at no extra cost. In combination these results greatly simplify gene cloning experiments. To demonstrate the utility of this strategy BSR-Seq was used to clone the glossy3 (gl3) gene of maize. Mutants of the glossy loci exhibit altered accumulation of epicuticular waxes on juvenile leaves. We previously generated a large collection of glossy mutants using the Mu transposon system. By subjected a reference allele to BSR-Seq, we were able to map the gl3 locus to a ~2.3Mb interval that is consistent with the results of prior mapping experiments. The single gene located in the 2.3Mb mapping interval that contained a Mu insertion and whose expression was down-regulated in the mutant pool was subsequently demonstrated to be the gl3 gene via the analysis of multiple independently Mu transposon induced mutant alleles. The gl3 gene encodes a putative myb transcription factor, which directly or indirectly affects the expression of a number of genes involved in the biosynthesis of very-long-chain fatty acids.
Changes in genome content generated via segregation of non-allelic homologs.
No sample metadata fields
View SamplesGastric cancer is still one of the most common causes of cancer-related death worldwide, which is mainly attributable to late diagnosis and poor treatment options. Infection with H. pylori, different environmental factors and genetic alterations are known to influence the risk of developing gastric tumors. However, the molecular mechanisms involved in gastric carcinogenesis are still not fully understood, making it difficult to design targeted therapeutic approaches.
The stem cell factor SOX2 regulates the tumorigenic potential in human gastric cancer cells.
Specimen part, Cell line, Treatment, Time
View SamplesDiabetes and obesity are widespread diseases with signifciant socioeconomic implications. We used three different types of human adipose tissue (epigastric, visceral, and subcutaneous) in order to determine differences in global gene expression between these adipose depots in severely obese patients.
Gene expression profiling in subcutaneous, visceral and epigastric adipose tissues of patients with extreme obesity.
Specimen part, Race
View SamplesLong noncoding RNAs (lncRNAs) have been implicated in numerous cellular processes including brain development. Yet the in vivo expression dynamics and molecular pathways regulated by these molecules are less well understood. Here, we leveraged a cohort of 13 lncRNA null-mutant mouse models to investigate the spatio-temporal expression of lncRNAs in the developing and adult brain. We observed a wide range of different spatio-temporal expression profiles in the brain. Several lncRNAs are differentially expressed both in time and space, and others present highly restricted expression in only selected brain regions. We further explore the consequent transcriptome alterations after loss of these lncRNA loci, and demonstrate altered regulation of a large variety of cellular pathways and processes. We further found that 6/13 lncRNA null-mutant strains significantly affect the expression of several neighboring protein-coding genes, in a cis-like manner. This resource provides insight into the expression patterns and potential effect of lncRNA loci in the developing and adult mammalian brain, and allows future examination of the specific functional relevance of these genes in neural development, brain function, and disease. We have sequenced wildtype and mutant whole brains from a cohort of 13 lncRNA knockout mouse strains at two developmetal timepoints (E14.5 and adult). Overall design: Comparison between wildtype and mutant whole brains transcriptomes in 13 lncRNA mutant strains at two different timepoints. Please note that for each knockout strain there are KO_E14.5 and KO_Adult samples, however for WT, each KO strain was compared to a cohort of 14 WTs (N3 background) and 3 WTs (N2.5 background) at either Adult or E14.5 timepoint. So in total there are 14 WT_Adult and 14 WT_E14.5 and in each differential analysis the 2 or 3 KOs (in N3 background) were compared to this entire cohort at the respective timepoint; a cohort of 3 WT_adult (N2.5) or 3 WT_E14.5 samples compared to other N2.5 KO samples at the respective timepoint. Thus, each processed data file was generated by comparing each KO strain to a cohort of WTs (at either Adult or E14.5 timepoint; ko_vs_WT_Adult or ko_vs_WT_embryonic). The mouse strain (background) used in these experiments a cross between 129 and C57BL/6 in the third generation (N3) of breeding in the C57BL/6 line, with the exception of the KANTR mice, which are N2.5.
Spatiotemporal expression and transcriptional perturbations by long noncoding RNAs in the mouse brain.
No sample metadata fields
View SamplesTo determine genes in FL HSCs that are sensitive to Notch signagling, E14.5 FL cells were cultured on DL1( to stimulate Notch signaling). Cells were cultured in the presence of DMSO (vehicle control) or gamma secretase inhibitor (1uM) for 4 hrs or 10hrs. Gamma secretase inhibitor was used to inhibit Notch signaling. SLAM-LSKs were sorted and used for RNA preparation.
The Notch1 transcriptional activation domain is required for development and reveals a novel role for Notch1 signaling in fetal hematopoietic stem cells.
Specimen part, Treatment, Time
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