This experiment was set up in order to identify the (direct) transcriptional targets of the Ethylene Response Factor 115 (ERF115) transcription factor. Because ERF115 expression occurs in quiescent center (QC) cells and strong effects on the QC cells were observed in ERF115 overexpression plants, root tips were harvested for transcript profiling in order to focus on root meristem and QC specific transcriptional targets.
ERF115 controls root quiescent center cell division and stem cell replenishment.
Age, Specimen part
View SamplesThe transcriptional coactivator ANGUSTIFOLIA 3 (AN3) stimulates cell proliferation during Arabidopsis leaf development, but the molecular mechanism is largely unknown. We show here that inducible nuclear localization of AN3 during initial leaf growth results in differential expression of important transcriptional regulators, including GROWTH REGULATING FACTORs (GRFs). Chromatin purification further revealed the presence of AN3 at the loci of GRF5, GRF6, CYTOKININ RESPONSE FACTOR 2 (CRF2), CONSTANS-LIKE 5 (COL5), HECATE 1 (HEC1), and ARABIDOPSIS RESPONSE REGULATOR 4 (ARR4). Tandem affinity purification of protein complexes using AN3 as bait identified plant SWITCH/SUCROSE NONFERMENTING (SWI/SNF) chromatin remodeling complexes formed around the ATPases BRAHMA (BRM) or SPLAYED (SYD). Moreover, SWI/SNF ASSOCIATED PROTEIN 73B (SWP73B) is recruited by AN3 to the promoter of GRF5, GRF3, COL5, and ARR4, and both SWP73B and BRM occupy the HEC1 promoter. Furthermore, we show that AN3 and BRM genetically interact. The data indicate that AN3 associates with chromatin remodelers to regulate transcription. In addition, modification of SWI3C expression levels increases leaf size, underlining the importance of chromatin dynamics for growth regulation. Our results place the SWI/SNF-AN3 module as a major player at the transition from cell proliferation to cell differentiation in a developing leaf.
ANGUSTIFOLIA3 binds to SWI/SNF chromatin remodeling complexes to regulate transcription during Arabidopsis leaf development.
Specimen part, Time
View SamplesTranscriptome comparisons by RNAseq of genetically engineered mouse models of synovial sarcoma, expressing SS18-SSX1 or SS18-SSX2 and having homozygous conditional genetic silencing of Pten or wildtype Pten. Overall design: 6 primary tumor samples with wildtype Pten, 8 primary tumor and 5 metastatic site tumor samples with homozygous disruption of Pten
Epigenetic Changes at the <i>Birc5</i> Promoter Induced by YM155 in Synovial Sarcoma.
Subject
View SamplesNeuroblastoma cell lines can differentiate upon retinoic acid (RA) treatment, a finding that provided the basis for the clinical use of RA to treat neuroblastoma. However, resistance to RA is often observed, which limits its clinical utility. Using a gain-of-function genetic screen we identify the transcriptional coactivator Mastermind-like 3 (MAML3) as a gene whose ectopic expression confers resistance to RA. We find that MAML3 expression leads to loss of activation of a subset of RA target genes, which hampers RA-induced differentiation. The regulatory DNA elements of this subset of RA target genes show overlap in binding of MAML3 and the retinoic acid receptor, suggesting a role for MAML3 in the regulation of these genes. In addition, MAML3 has RA independent functions, including the activation of IGF1R and downstream AKT signaling via upregulation of IGF2, resulting in increased proliferation. Our results indicate an important role for MAML3 in differentiation and proliferation of neuroblastomas. Overall design: RNA-seq of SK-N-SH control and MAML3 overexpressing (SD3.23) cells, either untreated (UT) or treated with 1 µM RA (RA).
Mastermind-Like 3 Controls Proliferation and Differentiation in Neuroblastoma.
No sample metadata fields
View SamplesCdc34 is an essential E2 ubiquitin conjugating enzyme found in nearly all eukaryotes. It contains a highly conserved motif composed of S73/S97/12 amino acid insert near the active site cysteine. This motif is unique to Cdc34/Ubc7 type E2s while other E2s contain K/D/no insert at these positions. To better understand the function of this motif we mutated Cdc34 S73/S97/insert to be K/D/no insert and observed changes in transcript levels in mid-log phase yeast cells. ABSTRACT [Cdc34 is a ubiquitin conjugating enzyme necessary for the ubiquitylation of substrates by the SCF family of ubiquitin ligases. Previous work has shown that the Cdc34 protein is phosphorylated in vivo on serine residues. Cdc34 contains two serines within its catalytic domain, S73 and S97, that together with a 12 amino acid acidic loop, constitute a highly conserved motif (serine, serine, insert) among all members of the Cdc34 family of E2 enzymes. Using phosphospecific antibodies, we show that the essential serine S97 is indeed phosphorylated in vivo. Furthermore, this phosphorylation event is regulated by treatment with pheromone in yeast. Consistently, expression of a Cdc34 mutant lacking this motif (serine, serine, insert) leads to misregulation of the SCF substrates, Sic1, Far1, Cln1 and Cln2 and suppresses the cell cycle arrest brought about by an activated mating pathway. We further explored the function of this motif by microarray analysis and show that the transcripts of nearly the entire Sic1 cluster of co-transcribed genes is altered in a strain the expresses Cdc34 lacking this motif. Our data reveals that this highly conserved motif in Cdc34 and its phosphorylation are important for modulating SCF substrate abundance both transcriptionally and post-transcriptionally.]
New insight into the role of the Cdc34 ubiquitin-conjugating enzyme in cell cycle regulation via Ace2 and Sic1.
No sample metadata fields
View SamplesTargeting immunomodulatory pathways has ushered a new era in lung cancer therapy. Further progress requires deeper insights into the nature and dynamics of immune cells in the lung cancer micro-environment. Dendritic cells (DCs) represent a heterogenous and highly plastic immune cell system with a central role in controlling immune responses. The intratumoral infiltration and activation status of DCs emerge as clinically relevant parameters in lung cancer. In this study we used an orthotopic preclinical model of lung cancer to interrogate the transcriptome of lung tumor-infiltrating DCs and extract novel biologically and clinically relevant information. Lung tumor-infiltrating leukocytes expressing generic DC markers were found to predominantly consist of CD11b+ cells which, compared to peritumoral lung DC counterparts, strongly over-express the T cell inhibitory molecule PD-L1 and acquire classic markers of tumor-supporting macrophages (TAM) on their surface. Transcriptome analysis of these CD11b+ tumor-infiltrating DCs (TIDCs) indicates impaired anti-tumoral immunogenicity, confirms the skewing towards TAM-related features, and indicates exposure to a hypoxic environment. In paralled, TIDCs display a specific micro-RNA signature dominated by the prototypical lung cancer oncomir miR-31. Hypoxia was found to drive intrinsic miR-31 expression in CD11b+DCs. Conditioned medium of mir-31-overexpressing CD11b+DCs induces pro-invasive lung cancer cell shape changes and is enriched with the pro-metastatic factors S100A8 and S100A9. Finally, analysis of TCGA datasets reveals that the TIDC-associated miRNA signature has a negative prognostic impact in non-small cell lung cancer. Together, these data suggest a novel mechanism through which lung cancer co-opts the plasticity of the DC system to support tumoral progression. Targeting immunomodulatory pathways has ushered a new era in lung cancer therapy. Further progress requires deeper insights into the nature and dynamics of immune cells in the lung cancer micro-environment. Dendritic cells (DCs) represent a heterogenous and highly plastic immune cell system with a central role in controlling immune responses. The intratumoral infiltration and activation status of DCs emerge as clinically relevant parameters in lung cancer. In this study we used an orthotopic preclinical model of lung cancer to interrogate the transcriptome of lung tumor-infiltrating DCs and extract novel biologically and clinically relevant information. Lung tumor-infiltrating leukocytes expressing generic DC markers were found to predominantly consist of CD11b+ cells which, compared to peritumoral lung DC counterparts, strongly over-express the T cell inhibitory molecule PD-L1 and acquire classic markers of tumor-supporting macrophages (TAM) on their surface. Transcriptome analysis of these CD11b+ tumor-infiltrating DCs (TIDCs) indicates impaired anti-tumoral immunogenicity, confirms the skewing towards TAM-related features, and indicates exposure to a hypoxic environment. In paralled, TIDCs display a specific micro-RNA signature dominated by the prototypical lung cancer oncomir miR-31. Hypoxia was found to drive intrinsic miR-31 expression in CD11b+DCs. Conditioned medium of mir-31-overexpressing CD11b+DCs induces pro-invasive lung cancer cell shape changes and is enriched with the pro-metastatic factors S100A8 and S100A9. Finally, analysis of TCGA datasets reveals that the TIDC-associated miRNA signature has a negative prognostic impact in non-small cell lung cancer. Together, these data suggest a novel mechanism through which lung cancer co-opts the plasticity of the DC system to support tumoral progression.
The transcriptome of lung tumor-infiltrating dendritic cells reveals a tumor-supporting phenotype and a microRNA signature with negative impact on clinical outcome.
Specimen part
View SamplesNine accessions of Arabidopsis were sampled before and after 14d of cold acclimation at 4°C. Transcript data were combined with metabolite data and related to quantitative measurement of plant freezing tolerance as determined by leaf electrolyte leakage assays.
Natural genetic variation of freezing tolerance in Arabidopsis.
Specimen part
View SamplesThe first embryonic cell divisions rely on maternally stored mRNA and proteins. The zygotic genome is initially transcriptionally silenced and activated later in a process called zygotic genome activation (ZGA). ZGA in any species is still a poorly understood process; the timing of transcription onset is controversial and the identity of the first transcribed genes unclear. Zebrafish, Danio rerio, is a rapidly developing vertebrate model, which is accessible to experimentation and global studies before, during and after ZGA. Overall design: To accurately determine the onset of ZGA and to identify the first transcripts in zebrafish, we developed a metabolic labeling method, utilizing the ribonucleotide analog 4-thio-UTP, which allows efficient and specific affinity purification of newly transcribed RNA. Using deep sequencing, we characterized the onset of transcription in zebrafish embryos at 128-, 256-, and 512-cell stages. We identified 592 nuclear-encoded zygotically transcribed genes, comprising 670 transcript isoforms. Mitochondrial genomes were highly transcribed at all time points. Further, bioinformatic analysis revealed an enrichment of transcription factors and miRNAs among the newly transcribed genes, suggesting mechanistic roles for the early genes that are required to activate subsequent gene expression programs in development. Interestingly, analysis of gene-architecture revealed that zygotically transcribed genes are often intronless and short, reducing transcription and processing time of the transcript. The newly generated dataset enabled us to compare zygotically transcribed genes over a broad phylogenetic distance with fly and mouse early zygotic genes. This analysis revealed that short gene length is a common characteristic for early zygotically expressed genes. However, we detected a poor level of overlap for shared orthologs.
The earliest transcribed zygotic genes are short, newly evolved, and different across species.
No sample metadata fields
View SamplesPurpose: We performed RNA-Immunoprecipitation in Tandem (RIPiT) experiments against human Staufen1 (Stau1) to identify its precise RNA binding sites in a transcriptome-wide manner. To monitor the consequences of Stau1 binding in terms of target mRNA levels and ribosome occupancy, we modified the levels of endogenous Stau1 in cells by siRNA or overexpression and performed RNA-sequencing and ribosome-footprinting experiments. Staufen1 (Stau1) is a double-stranded RNA (dsRNA) binding protein implicated in mRNA transport, regulation of translation, mRNA decay and stress granule homeostasis. Here we combined RNA-Immunoprecipitation in Tandem (RIPiT) with RNase footprinting, formaldehyde crosslinking, sonication-mediated RNA fragmentation and deep sequencing to map Staufen1 binding sites transcriptome-wide. We find that Stau1 binds complex secondary structures containing multiple short helices, many of which are formed by inverted Alu elements in annotated 3''UTRs or in "strongly distal" 3''UTRs extending far beyond the canonical polyadenylation signal. Stau1 also interacts with both actively translating ribosomes and with mRNA coding sequences (CDS) and 3''UTRs in proportion to their GC-content and internal secondary structure-forming propensity. On mRNAs with high CDS GC-content, higher Stau1 levels lead to greater ribosome densities, suggesting a general role for Stau1 in modulating the ability of ribosomes to elongate through secondary structures located in CDS regions. Overall design: We used HEK293 cells expressing near endogenous levels of wild-type Flag-Stau1 (65KDa isoform with an N-Terminal Flag tag). As a control we used a mutant version of Stau1 that is not functional for dsRNA binding. Formaldehyde crosslinking experiments and RNase footprinting experiments were done in two biological replicates. All RNASeq, Ribosome footprinting and PAS-Seq were done in two biological replicates.
Staufen1 senses overall transcript secondary structure to regulate translation.
No sample metadata fields
View SamplesUsing a chromatin regulator-focused shRNA library, we found that suppression of sex determining region Y-box 10 (SOX10) in melanoma causes resistance to BRAF and MEK inhibitors. To investigate how SOX10 loss leads to drug resistance, we performed transcriptome sequencing (RNAseq) of both parental A375 (Ctrl. PLKO) and A375-SOX10KD (shSOX10-1, shSOX10-2) cells. To ask directly whether SOX10 is involved indrug resistance in BRAF(V600E) melanoma patients, we isolated RNA from paired biopsies from melanoma patients (pre- and post- treatment) , that had gained BRAF or MEK inhibitor resistance . We performed RNAseq analysis to determine changes in transcriptome upon drug resistance. Overall design: Investigate genes regulated by SOX10 and differntial gene expression between pre- and post-treatment biopsies. We use short hairpin RNA to suppression SOX10 in A375 cells and cells were harvested with trizol reagent for RNA isolation. For paired biopsies (patient samples) we collected the first biopsy before the initiation of treatment and the second biopsy after drug resistance developed. RNA was isolated from FFPE samples and subjected for RNA sequencing.
Reversible and adaptive resistance to BRAF(V600E) inhibition in melanoma.
Sex, Age, Specimen part, Cell line, Subject
View Samples