Mammalian gonadal sex determination is dependent on proper expression of sex determining genes in fetal gonadal somatic support cells (i.e., pre-granulosa and pre-Sertoli cells in XX and XY gonads, resp.). We used a unique transgenic mouse strain combined with microarray profiling to identify all the differentially expressed transcripts in XX and XY isolated somatic support cells during critical stages of gonadal development and differentiation.
New candidate genes identified for controlling mouse gonadal sex determination and the early stages of granulosa and Sertoli cell differentiation.
Sex, Specimen part
View SamplesTranscription termination factor Rho is essential in enterobacteria. We inhibited Rho activity with bicyclomycin and used microarray experiments to assess Rho function on a genome-wide scale. Rho is a global regulator of gene expression that matches E. coli transcription to translational needs. Remarkably, genes that are most repressed by Rho are prophages and other horizontally-acquired portions of the genome. Elimination of these foreign DNA elements increases resistance to bicyclomycin. Although rho remains essential, such reduced-genome bacteria no longer require Rho cofactors NusA and NusG. Thus, Rho termination, supported by NusA and NusG, is required to suppress the toxic activity of foreign DNA.
Termination factor Rho and its cofactors NusA and NusG silence foreign DNA in E. coli.
Compound
View SamplesWe report the total RNA-seq results after CDK9, CDK12 and CDK13 depletion in human HCT116 cells for three days. RNA-seq was performed in cells using two non-targeting replicates and two different shRNAs for each CDK knockdown. For each CDK knockdown, most of the differentially expressed genes were down-regulated with a very small subset of genes upregulated. Different CDK proteins control distinct subsets of genes in vivo, with CDK12 and CDK13 sharing more overlap in function compared to CDK9. Besides, CDK12 and CDK13 loss preferentially affects DNA damage response and snRNA gene expression, respectively. Overall design: Examine the changes of mRNA expression levels after CDK9, CDK12 and CDK13 depletion.
Characterization of human cyclin-dependent kinase 12 (CDK12) and CDK13 complexes in C-terminal domain phosphorylation, gene transcription, and RNA processing.
No sample metadata fields
View SamplesPurpose: The purpose of this experiment is to expand the repertoire of C. elegans edited transcripts and identify the roles of ADR-1 as indirect regulator of editing and ADR-2 as the only active deaminase in vivo. Methods: Strand-specific RNA sequencing of wild-type and adr mutant worms, followed by a novel RNA variant calling and comparative analysis pipeline. Results: Despite lacking deaminase function, ADR-1 affects editing of over 60 adenosines within the 3’ UTRs of 16 different mRNAs. Furthermore, ADR-1 interacts directly with ADR-2 substrates, even in the absence of ADR-2; and mutations within its dsRNA binding domains abolished both binding and editing regulation. Conclusions: ADR-1 acts as a major regulator of editing by binding ADR-2 substrates in vivo and raises the possibility that other dsRNA binding proteins, including the inactive human ADARs, regulate RNA editing by deaminase-independent mechanisms. Overall design: Strand-specific RNA sequencing of wild-type and adr mutant worms, followed by a novel RNA variant calling and comparative analysis pipeline.
The dsRBP and inactive editor ADR-1 utilizes dsRNA binding to regulate A-to-I RNA editing across the C. elegans transcriptome.
Specimen part, Subject
View SamplesCoordinate expression of the somatic cell reprogramming factors Oct4, Sox2, Klf4 and c-Myc within embryonic stem cells preserves the self-renewal of these cells, while allowing for the expression epitope tagged Sox2. Taking advantage of this observation, we engineered embryonic stem cells (i-OSKM-ESC) to inducibly express Oct4, Klf4, c-Myc and an epitope tagged form of Sox2 from a polycistronic element, in the presence of doxycycline. We isolated Sox2 and its associated protein complexes by co-immunoprecipitation. Subsequently, we identified the Sox2-protein interactome in self-renewing embryonic stem cells using an unbiased proteomic screen (Multidimensional Protein Identification Technology [MudPIT]).
Determination of protein interactome of transcription factor Sox2 in embryonic stem cells engineered for inducible expression of four reprogramming factors.
Specimen part
View SamplesThe Sin3 histone deacetylase (HDAC) complex is a 1.2 MDa chromatin modifying complex that can repress transcription by binding to gene promoters and deacetylating histones. The Sin3/HDAC complex can affect cell cycle progression through multiple mechanisms and is among the targets of anticancer drugs, called HDAC inhibitors. We describe the identification of a new subunit of the Sin3 complex named family with sequence similarity 60 member A (FAM60A). We show that FAM60A/Sin3 complexes normally suppress the epithelial-to-mesenchymal transition (EMT) and cell migration. This occurs through transcriptional repression of genes that encode components of the TGF-beta signaling pathway. This work reveals that FAM60A and the Sin3 complex are upstream repressors of TGF-beta signaling, EMT and cell migration and extends the known biological roles of the Sin3 complex. This experiment investigates the role of FAM60A in gene expression by comparing A549 lung cancer cells treated with or without siRNA against FAM60A.
Human family with sequence similarity 60 member A (FAM60A) protein: a new subunit of the Sin3 deacetylase complex.
Specimen part, Cell line
View SamplesThe development of affinity purification technologies together with mass spectrometric analyses of the purified protein mixtures (AP-MS) has been used both to identify new protein-protein interactions and to define the subunit composition of protein complexes. Transcription factor protein interactions, however, have not been systematically analyzed using these approaches. Here, we have investigated whether ectopic expression of an affinity tagged transcription factor as bait in AP-MS experiments perturbs gene expression in cells resulting in false positive identification of bait associated proteins when typical experimental controls are used. Using quantitative proteomics and RNA-Seq, we determined that the increase in the abundance of a set of proteins caused by overexpression of the transcription factor RelA is not sufficient for these proteins to then copurify non-specifically and be misidentified as bait associated proteins. Therefore typical controls should be sufficient and a number of different baits can be compared with a common set of controls. This is of practical interest when identifying bait interactors from a large number of different baits. As expected, we found several known RelA interactors enriched in our RelA purifications (NFêB1, NFêB2, Rel, RelB, IêBá, IêBâ and IêBå). We also found several proteins not previously described in association with RelA, including the small mitochondrial chaperone Tim13. Using a variety of biochemical approaches, we further investigated the nature of the association between Tim13 and NFêB family transcription factors. The work here therefore provides a conceptual and experimental framework for analyzing transcription faction protein interactions. Overall design: Gene expression profiles were assayed in triplicate from HEK293 cells expressing either Halo-RelA, Halo-NFkB1, or Halo tag alone.
Controlling for gene expression changes in transcription factor protein networks.
No sample metadata fields
View SamplesThis experiment analyzes the set of RNAs copurifying with the protein TNIP2 (amino acids 196-346) Overall design: HEK293 cells were transfected with constructs expressing either Halo tag (controls) or Halo-TNIP2 196-346. Total RNA was purified from an aliquot of the whole cell extract (Input samples). Halo-tagged proteins were purified from the remainder of the whole cell extract, and RNA subsequently purified from the Halo purified samples (Pulldown samples).
TNIP2 is a Hub Protein in the NF-κB Network with Both Protein and RNA Mediated Interactions.
Cell line, Subject
View SamplesHistone H3 lysine27-to-methionine (H3K27M) gain-of-function mutations occur in highly aggressive pediatric gliomas. Here, we establish a Drosophila animal model for the pathogenic histone H3K27M mutation and show that its overexpression resembles Polycomb repressive complex 2 (PRC2) loss-of-function phenotypes, causing de-repression of PRC2 target genes and developmental perturbations. Similarly, a H3K9M mutant depletes H3K9 methylation levels and suppresses position-effect variegation in various Drosophila tissues. The histone H3K9 demethylase KDM3B/JHDM2 associates with H3K9M nucleosomes and its overexpression in Drosophila results in loss of H3K9 methylation levels and heterochromatic silencing defects. Here we establish histone lysine-to-methionine mutants as robust in vivo tools for inhibiting methylation pathways that also function as biochemical reagents for capturing site-specific histone-modifying enzymes, thus providing molecular insight into chromatin-signaling pathways. Overall design: RNA-seq of wing imaginal discs expressing either H3.3WT-FLAG-HA or H3.3K27M-FLAG-HA.
Histone H3 lysine-to-methionine mutants as a paradigm to study chromatin signaling.
Specimen part, Subject
View SamplesThe mammalian Retinoblastoma (RB) family including pRB, p107, and p130 represses E2F target genes through mechanisms that are not fully understood. In D. melanogaster, RB-dependent repression is mediated in part by the multisubunit protein complex Drosophila RBF, E2F, and Myb (dREAM) that contains homologs of the C. elegans synthetic multivulva class B (synMuvB) gene products. Using an integrated approach combining proteomics, genomics, and bioinformatic analyses, we identified a p130 complex termed DP, RB-like, E2F, and MuvB (DREAM) that contains mammalian homologs of synMuvB proteins LIN-9, LIN-37, LIN-52, LIN-54, and LIN-53/RBBP4. DREAM bound to more than 800 human promoters in G0 and was required for repression of E2F target genes. In S phase, MuvB proteins dissociated from p130 and formed a distinct submodule that bound MYB. This work reveals an evolutionarily conserved multisubunit protein complex that contains p130 and E2F4, but not pRB, and mediates the repression of cell cycle-dependent genes in quiescence.
Evolutionarily conserved multisubunit RBL2/p130 and E2F4 protein complex represses human cell cycle-dependent genes in quiescence.
No sample metadata fields
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