Project description:C2H2 zinc finger proteins represent the largest and most enigmatic class of human transcription factors. Their C2H2 arrays are highly variable, indicating that most will have unique DNA binding motifs. However, most of the binding motifs have not been directly determined. We have determined the binding sites and motifs of 119 C2H2 zinc finger proteins and the expression pattern of 80 cell lines overexpressing C2H2 zinc finger proteins in order to study the role of C2H2 zinc finger proteins in gene regulation. We expressed GFP-tagged C2H2-ZF proteins in stable transgenic HEK293 cells. Total RNA was isolated using Trizol and sequencing libraries were constructed using TruSeq Stranded Total RNA Library Prep Kit with Ribo-Zero Gold or TruSeq RNA Library Preparation Kit v2.
Project description:The largest and most diverse class of eukaryotic transcription factors contain Cys2-His2 zinc fingers (C2H2-ZFs), each of which typically binds a DNA nucleotide triplet within a larger binding site. Frequent recombination and diversification of their DNA-contacting residues suggests that these zinc fingers play a prevalent role in adaptive evolution. Very little is known about the function and evolution of the vast majority of C2H2-ZFs, including whether they even bind DNA. We determined in vivo binding sites of 39 human C2H2-ZF proteins, and correlated them with potential functions for these proteins. We expressed GFP-tagged C2H2-ZF proteins in stable transgenic HEK293 cells. Chromatin immunoprecipitation was performed as described before (Schmidt et al., Methods, 2009), and ChIP samples along with several control samples from different experimental batches were sequenced on Illumina HiSeq 2000. Reads were mapped to hg19 (GRCh37) assembly, and peaks were identified by MACS using an experiment-specific background that controls for various biases, such as the Sono-Seq effect as well as potential co-purification of targets of other (interacting) proteins.
Project description:The largest and most diverse class of eukaryotic transcription factors contain Cys2-His2 zinc fingers (C2H2-ZFs), each of which typically binds a DNA nucleotide triplet within a larger binding site. Frequent recombination and diversification of their DNA-contacting residues suggests that these zinc fingers play a prevalent role in adaptive evolution. Very little is known about the function and evolution of the vast majority of C2H2-ZFs, including whether they even bind DNA. We determined in vivo binding sites of 39 human C2H2-ZF proteins, and correlated them with potential functions for these proteins. We expressed GFP-tagged C2H2-ZF proteins in stable transgenic HEK293 cells. Chromatin immunoprecipitation was performed as described before (Schmidt et al., Methods, 2009), and ChIP samples along with several control samples from different experimental batches were sequenced on Illumina HiSeq 2500. Reads were mapped to hg19 (GRCh37) assembly, and peaks were identified by MACS using an experiment-specific background that controls for various biases, such as the Sono-Seq effect as well as potential co-purification of targets of other (interacting) proteins.
Project description:This SuperSeries is composed of the SubSeries listed below. Cys2-His2 zinc finger (C2H2-ZF) proteins represent the largest class of putative human transcription factors (TFs). However, it is unknown whether most C2H2-ZFs even bind DNA, or what sequences they bind. Using a combination of bacterial one-hybrid (B1H) assays, protein-binding microarrays (PBMs), and ChIP-seq, we have found that most natural C2H2-ZFs bind DNA both in vitro and in vivo. This SuperSeries contains the data for identification of C2H2-ZF binding preferences using these three approaches. Refer to individual Series
Project description:Transcription termination was analyzed by anti RNA pol II ChIP-seq in isogenic human HEK293 cell lines that inducibly express a-amanitin resistant mutants of the RNA polymerase II large subunit with slow and fast elongation rates and in lines that inducbily over-express WT or an active site mutant of the RNA exonuclease "torpedo" Xrn2. Transcription termination zones were mapped by anti-pol II ChIP-seq under conditions where transcription elongation rate was increased or decreased by point mutations in the large subunit of the enzyme. Termination was also assayed under conditions where Xrn2 exonuclease activity was inhibited by over-expression of an active site mutant (D235A).
Project description:We report the knockdown and rescue of RNPS1, a component of the ASAP and PSAP complexes and, hence, an auxiliary component of the exon junction complex. The studied conditions show an extensive change in alternative splicing and the cell's transcriptome. For the knockdown, HeLa cells were transfected with siRNAs targeting RNPS1 or the Luciferase control. Total RNA was extracted with peqGOLD TriFast, underwent ribosomal depletion and strand-specific library preparation (TruSeq R Stranded Total RNA LT). Sequencing occurred in an Illumina HiSeq4000 sequencer with 2×75bp, producing roughly 35 million read-pair per sample.
Project description:To uncover exon junction complex (EJC) deposition sites on cellular mRNAs, RNA footprints of EJC immuo-purified from HEK293 cells were deep sequenced. The analysis of these data revealed that major “canonical” EJC occupancy site in vivo lies 24 nucleotides upstream of exon junctions (-24 position) and that the majority of exon junctions carry an EJC. Unexpectedly, we find that many sites further upstream of -24 position are also enriched in these EJC footprints. These "non-canonical" sites are binding sites of EJC-interacting proteins with a subset being occupied by SR proteins. Thus, an EJC-SR protein nexus exists within spliced mRNPs and is revealed here. Deep sequencing based profiling of EJC RNA footprints obtained by tandem RNA immunoprecipitation (RIPiT) of RNase I digested RNA:protein complexes.
Project description:Cells were starved for leucine in the presence or absence of a dominant negative HSF1 mutant (dnHSF1, HSF379). Changes in transcriptome relative to cells cultured with leucine were determined. The experiment shows the effect of dnHSF on the amino acid starvation response.
Project description:Although splicing occurs in most multi-exon genes, the generation of distinct isoforms through the alternate use of mutually exclusive exons is less prevalent. As exon-switching events have the potential to give rise to isoforms with different cellular functions, we have explored the role of the muscle-specific (Mef2Da2) and ubiquitously expressed (Mef2Da1) isoforms of the transcription factor Mef2D in myogenesis. Here we show that both isoforms of Mef2D bind a largely overlapping subset of genomic loci, yet only the muscle-specific Mef2Da2 isoform can activate the late myogenic gene expression program. This differential ability to activate transcription is modulated by PKA signaling where Mef2Da1 is efficiently phosphorylated by the kinase to enhance its association with repressive HDAC-deacetylase complexes. In contrast, alternate exon usage in Mef2Da2 renders the protein resistant to PKA phosphorylation, allowing it to interact with transcriptionally permissive Ash2L-trithorax complex. Our findings support a model wherein alternative exon usage allows Mef2D to transition from a repressor to activator in a myogenic environment rich in PKA activity. Thus we have identified a novel paradigm in which a ubiquitously expressed transcription factor has evolved to undergo tissue-specific alternative exon usage to permit the proper temporal activation of a gene expression program during differentiation. RNA-Seq profiling of C2C12 cells with exogenous expression of Mef2Da1 and Mef2Da2