In order to gain insight into relative stability of transcripts in plants that lacked m6A, we performed global mapping of uncapped and cleaved transcripts Overall design: 2 replicates of GMUCT in Arabidopsis thaliana ecotype Col-0 ABI3:MTA (mta) plants. genome-wide mapping of uncapped and cleaved transcripts (GMUCT)
N<sup>6</sup>-Methyladenosine Inhibits Local Ribonucleolytic Cleavage to Stabilize mRNAs in Arabidopsis.
Specimen part, SubjectView Samples
To identify RNA transcripts involved in acute and chronic renal epithelial injury, we performed unbiased whole transcriptome profiling of human proximal tubular epithelial cells (PTECs) in hypoxic and inflammatory conditions. RNA sequencing (RNA-seq) revealed that the protein-coding and noncoding transcriptomic landscape differed between hypoxia-stimulated and cytokine-stimulated human PTECs. Overall design: Examination of transcriptomic response of human PTECs to hypoxic or inflammatory injury
The long noncoding RNA landscape in hypoxic and inflammatory renal epithelial injury.
Specimen part, Treatment, SubjectView Samples
Purpose: Cellular senescence is a cell stress response resulting in permanent growth arrest and the production of an altered pro-inflammatory secretory profile known as the senescecnce-associated secretory phenotype (SASP). The induction of senescence in astrocytes, a cell type responsible for maintaining homeostasis within the central nervous system (CNS) and responding to CNS insults, has been implicated in neurodegenerative disease. However, little is known about the senescent transcriptome in CNS-derived cell types including astrocytes. Methods: To better understand senescence-associated gene expression changes in astrocytes, we investigated global changes in the astrocyte transcriptome using RNA-seq following the induction of oxidative stress-induced senescence with hydrogen peroxide. Results: During senescence, we find evidence of a loss of brain expressed transcripts involved in diverse CNS processes including neuronal differentiation and development, gliogenesis, axonogenesis, and learning and memory as well as a loss of transcripts involved in MHC class II antigen processing and presentation. In addition, we find evidence for induction of the senescent phenotype including a loss of transcripts involved in cell division and an increase in the mRNA level of inflammatory mediators suggestive of a SASP. Conclusions: Overall, our findings suggest a loss of differentiated function in senescent astrocytes and a gain in neuroinflammatory function as part of the SASP as a potential mechanisms for dysfunction in the aging brain. Overall design: Examination of transcriptome changes by RNAseq in pre-senescent and senescent astrocytes using 2 biological replicates per condition
Changes in the Transcriptome of Human Astrocytes Accompanying Oxidative Stress-Induced Senescence.
No sample metadata fieldsView Samples
Using RNA-Seq, we reported novel findings in the comparison of transcriptome profiles of isogenic HMDM and IPSDM during differentiation and polarization. First, IPSDM lost expression of pluripotency markers, had remarkably distinct gene expression profiles relative to precursor iPSCs, and had largely similar gene expression as HMDM. Second, macrophage polarization to M1 was associated with a dramatic change in the transcriptome; expression profiles of IPSDM- and HMDM-derived M1 lines were highly correlated with each other but much less so with their respective IPSDM and HMDM precursors. Third, M2-HMDM lines had limited difference in gene expression compared to their non-polarized precursors, likely due to the known M2-like phenotype of M-CSF differentiated macrophages and their similarity to the IL-4 derived M2 phenotype Finally, through RNA-Seq we identified many new genes modulated during polarization in both HMDM and IPSDM thus providing novel, and potentially regulatory, candidates that warrant further study. Overall design: iPS, IPSDM (including M1/M2) and HMDM (including M1/M2)cells were sequenced by Illumina HiSeq 2000 with poly-A selection
Functional analysis and transcriptomic profiling of iPSC-derived macrophages and their application in modeling Mendelian disease.
No sample metadata fieldsView Samples
There is a critical need in cancer therapeutics to identify targeted therapies that will improve outcomes and decrease toxicities compared to conventional, cytotoxic chemotherapy. Ewing sarcoma is a highly aggressive bone and soft tissue cancer that is caused by the EWS-FLI1 fusion protein. Although EWS-FLI1 is specific for cancer cells, and required for tumorigenesis, directly targeting this transcription factor has proven challenging. Consequently, targeting unique dependencies or key downstream mediators of EWS-FLI1 represent important alternative strategies. We used gene expression data derived from a genetically defined model of Ewing sarcoma to interrogate the Connectivity Map and identify a class of drugs, iron chelators, that downregulate a significant number of EWS-FLI1 target genes. We then identified ribonucleotide reductase M2 (RRM2), the iron-dependent subunit of ribonucleotide reductase (RNR), as one mediator of iron chelator toxicity in Ewing sarcoma cells. Inhibition of RNR in Ewing sarcoma cells led to apoptosis and cell death in vitro and attenuated tumor growth in vivo in a xenograft model. Additionally, we discovered that the sensitivity of Ewing sarcoma cells to inhibition or suppression of RNR is mediated, in part, by high levels of SLFN11, a protein that sensitizes cells to DNA damage. This work demonstrates a unique dependency of Ewing sarcoma cells on RNR and supports further exploration of clinically used inhibitors of RNR as a therapeutic approach in treating this cancer.
Gene expression signature based screening identifies ribonucleotide reductase as a candidate therapeutic target in Ewing sarcoma.
Specimen part, Cell line, TreatmentView Samples
Experiments performed over the past three decades have shown that nucleosomes are transcriptional repressors. In Saccharomyces cerevisiae, depletion of histone H4 results in the genome-wide transcriptional de-repression of hundreds genes. The mechanism of de-repression is hypothesized to be rooted directly in chromatin changes. To test this, we reproduced classical H4 depletion experiments by conditional repression of all histone H3 transcription, which depletes the supply of nucleosomes in vivo. RNA-seq results were consistent with the earlier studies, but much more sensitive, revealing nearly 2500 de-repressed genes. Changes in chromatin organization were determined by MNase-seq. Nucleosomes that were preferentially retained occurred in regions of high DNA-encoded nucleosome affinity, and were marked with H3K36me2, which is linked to transcription elongation. Nucleosomes harboring acetyl marks or that contained the variant histone H2A.z were preferentially lost. Genes that were de-repressed lost or rearranged nucleosomes at their promoter, but not in the gene body. Therefore, a combination of DNA-encoded nucleosome stability and nucleosome composition dictates which nucleosomes will be lost under conditions of limiting histone protein. This, in turn, governs which genes will experience a loss of regulatory fidelity. Overall design: MNase-seq experiments consist of three wildtype (1 single-end and 2 paired-end) and four mutant (DCB200.1/H3 shutoff; 2 single-end, 2 paired-end) replicates. Each replicate contains two timepoints reflecting chromatin immediately after ("O hours") and 3 hours after transition to media containing dextrose. RNA-seq data includes three replicates from wildtype or H3 depleted cells after 3 hours in media containing dextrose.
In vivo effects of histone H3 depletion on nucleosome occupancy and position in Saccharomyces cerevisiae.
Cell line, Subject, TimeView Samples
Huntington disease (HD) is associated with increased nuclear accumulation of the repressor element-1 silencing transcription factor (REST) which govens a huge gene network. An alternative REST splicing event (E3) eliminates a motif essential for nuclear targeting of REST.
Modulation of nuclear REST by alternative splicing: a potential therapeutic target for Huntington's disease.
Cell line, TreatmentView Samples
Mechanical overload in the heart induces pathological remodeling that typcially leads to heart failure. We sought to build an in vitro model of heart failure by applying cyclic stretch to engineered isotropic (iso) and anisotropic (aniso) NRVM tissues.
Recapitulating maladaptive, multiscale remodeling of failing myocardium on a chip.
Specimen partView Samples
Interaction of hematopoietic progenitors with the thymic stromal microenvironment induces them to proliferate, adopt the T cell fate, and asymmetrically diverge into multiple T lineages. Progenitors at various developmental stages are stratified among different regions of the thymus, implying that the corresponding microenvironments differ from one another, and provide unique sets of signals to progenitors migrating between them. The nature of these differences remains undefined. Here we use novel physical and computational approaches to characterize these stromal subregions, distinguishing gene expression in microdissected tissues from that of their lymphoid constituents. Using this approach, we comprehensively map gene expression in functionally distinct stromal microenvironments, and identify clusters of genes that define each region. Quite unexpectedly, we find that the central cortex lacks distinctive features of its own, and instead appears to function by sequestering unique microenvironments found at the cortical extremities, and modulating the relative proximity of progenitors moving between them.
Spatial mapping of thymic stromal microenvironments reveals unique features influencing T lymphoid differentiation.
Specimen partView Samples
Although mutations in Kras are present in 21% of lung tumors, there is a high level of heterogeneity in phenotype and outcomes amongst lung cancer patients suggesting the importance of other pathways. Wnt/-catenin signaling is a known oncogenic pathway that plays a well defined role in colon and skin cancer but its role in lung cancer remains unclear. We show that activation of Wnt/-catenin in the bronchiolar epithelium of the adult lung does not promote tumor development by itself. However, activation of Wnt/- catenin signaling leads to a dramatic increase in tumor formation both in overall tumor number and size compared to KrasG12D alone. We show that activation of Wnt/- catenin signaling significantly alters the KrasG12D tumor phenotype resulting in a phenotypic switch from bronchiolar epithelium to the highly proliferative distal progenitors found in the embryonic lung. This is associated with a decrease in E- cadherin expression at the cell surface which may increase metastasis in Wnt/-catenin signaling positive tumors. Together, these data suggest that activation of Wnt/-catenin signaling in combination with other oncogenic pathways in lung epithelium may lead to a more aggressive phenotype due to the imposition of an embryonic distal progenitor phenotype accompanied by decreased E-cadherin expression.
Wnt/β-catenin signaling accelerates mouse lung tumorigenesis by imposing an embryonic distal progenitor phenotype on lung epithelium.
Sex, Age, Specimen partView Samples