Pre-mRNA splicing is functionally coupled to transcription, and genotoxic stresses can enhance alternative exon inclusion by affecting elongating RNA polymerase II. We report here that various genotoxic stress inducers, including camptothecin, inhibit the interaction between EWS, an RNA polymerase II-associated factor, and YB-1, a spliceosome-associated factor. This results in the cotranscriptional skipping of several exons of the MDM2 gene encoding the main p53 ubiquitin-ligase. This reversible exon skipping participates in the timely regulation of MDM2 expression, and may contribute to the accumulation of p53 during stress exposure and its rapid shut off when stress is removed. Finally, a splicing-sensitive microarray identified numerous exons that are skipped in response to camptothecin and EWS/YB-1 depletion. These data demonstrate genotoxic stress-induced alteration of the communication between the transcriptional and splicing machineries, resulting in widespread exon skipping and playing a central role in the genotoxic stress response.
Cotranscriptional exon skipping in the genotoxic stress response.
Specimen part, Cell line
View SamplesWe showed that a large number of genes and exons were deregulated in colorectal adenomas in comparison with colorectal normal mucosa.
A gene expression and pre-mRNA splicing signature that marks the adenoma-adenocarcinoma progression in colorectal cancer.
Specimen part
View SamplesMarek’s disease virus 1 (MDV-1), an oncogenic -herpesvirus that induces T-cell lymphomas in chickens, serves as model system to study transformation by lymphotropic herpesviruses. Like the oncogenic human -herpesviruses Kaposi’s sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV), MDV-1 encodes several viral microRNAs (miRNAs). One MDV-1 miRNA, miR-M4, shares the same “seed” targeting sequence with both a KSHV miRNA, miR-K11, and cellular miR-155. Importantly, miR-M4 plays a critical role in T-cell transformation by MDV-1, while miR-K11 and cellular miR-155 are thought to play key roles in B-cell transformation by KSHV and EBV, respectively. Here, we present an analysis of the mRNAs targeted by viral miRNAs expressed in the chicken T-cell line MSB1, which is naturally coinfected with MDV-1 and the related nonpathogenic virus MDV-2. Our analysis identified>1,000 endogenous mRNAs targeted by miRNAs encoded by each virus, many of which are targeted by both MDV-1 and MDV-2 miRNAs. We present a functional analysis of an MDV-1 gene, RLORF8, targeted by four MDV-1 miRNAs and a cellular gene, encoding interleukin-18 (IL-18) and targeted by both MDV-1 and MDV-2 miRNAs, and show that ectopic expression of either protein in a form resistant to miRNA inhibition results in inhibition of cell proliferation. Finally, we present a restricted list of 9 genes targeted by not only MDV-1 miR-M4 but also KSHV miR-K11 and human miR-155. Given the critical role played by miR-155 seed family members in lymphomagenesis in humans and chickens, these mRNA targets may contain genes whose inhibition plays a conserved role in herpesvirus transformation. Overall design: PAR-CLIP experiment of MSB1 cells
Analysis of the mRNA targetome of microRNAs expressed by Marek's disease virus.
Specimen part, Cell line, Subject
View SamplesThe chromatin regulator Aiolos and the transcriptional coactivator OBF-1 have been implicated in regulating aspects of B cell maturation and activation. Mice lacking either of these factors have a largely normal early B cell development. However, when both factors are eliminated simultaneously a block is uncovered at the transition between pre-B and immature B cells, indicating that these proteins exert a critical function in developing B lymphocytes. In mice deficient for Aiolos and OBF-1, the numbers of immature B cells are reduced, small pre-BII cells are increased and a significant impairment in immunoglobulin light chain DNA rearrangement is observed. We identified genes whose expression is deregulated in the pre-B cell compartment of these mice. In particular, we found that components of the pre-BCR, such as the surrogate light chain genes l5l5 and VpreB, fail to be efficiently silenced in double-mutant mice. Strikingly, developmentally regulated nuclear repositioning of the l5l5 gene is impaired in pre-B cells lacking OBF-1 and Aiolos. These studies uncover a novel role for OBF-1 and Aiolos in controlling the transcription and nuclear organization of genes involved in pre-BCR function.
Silencing and nuclear repositioning of the lambda5 gene locus at the pre-B cell stage requires Aiolos and OBF-1.
No sample metadata fields
View SamplesInvestigation of mRNA changes in podocytes transfected with a miR-93 mimic or a nontargeting mimic. Overall design: The design was meant to identify biologically significant, novel targets of the miR-93 microRNA in podocytes
miR-93 regulates Msk2-mediated chromatin remodelling in diabetic nephropathy.
No sample metadata fields
View SamplesMicroglia-like cells and neural cells were generated from several hES and hIPS lines. As subset was characterized by RNA seq and compared to expression profiles of published primary and induced samples. ABSTRACT: Microglia, the only lifelong resident immune cells of the central nervous system (CNS), are highly specialized macrophages which have been recognized to play a crucial role in neurodegenerative diseases such as Alzheimer's, Parkinson's and Adrenoleukodystrophy (ALD). However, in contrast to other cell types of the human CNS, bona fide microglia have not yet been derived from cultured human pluripotent stem cells. Here we establish a robust and efficient protocol for the rapid production of microglia-like cells from human embryonic stem (ES) and induced pluripotent stem (iPS) cells that uses defined serum-free culture conditions. These in vitro pluripotent stem cell-derived microglia-like cells (termed pMGLs) faithfully recapitulate the expected ontogeny and characteristics of their in vivo counterparts and resemble primary fetal human and mouse microglia. We generated these cells from multiple disease-specific cell lines, and find that pMGLs derived from MeCP2 mutant hES cells are smaller than their isogenic controls. We further describe a culture platform to study integration and live behavior of pMGLs in organotypic 3D-cultures. This modular differentiation system allows the study of microglia in highly defined conditions, as they mature in response to developmentally relevant cues, and provides a framework to study the long-term interaction of microglia residing in a tissue-like environment. Overall design: Individual donors/genetic backgrounds. Dataset inlcudes 4 differentiated neural progenitor biological replicates (NPC1-4), 2 primary fetal microglia samples as reference, 5 induced microglia samples grown in basal medium (pMGL1-5), 3 induced microglia samples grown in neural conditioned medium (pMGL1-3+NCM)
Efficient derivation of microglia-like cells from human pluripotent stem cells.
Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integrative regulatory mapping indicates that the RNA-binding protein HuR couples pre-mRNA processing and mRNA stability.
Specimen part
View SamplesIntegrative regulatory mapping indicates that the RNA-binding protein HuR (ELAVL1) couples pre-mRNA processing and mRNA stability
Integrative regulatory mapping indicates that the RNA-binding protein HuR couples pre-mRNA processing and mRNA stability.
Specimen part
View SamplesDivergent transcription, in which reverse-oriented transcripts occur upstream of eukaryotic promoters in regions devoid of annotated genes, has been suggested to be a general property of active promoters. Here we show that the human basal RNA polymerase II transcriptional machinery and core promoter are inherently unidirectional, and that reverse-oriented transcripts originate from their own cognate reverse-directed core promoters. In vitro transcription analysis and mapping of nascent transcripts in cells revealed that core promoters are unidirectional and that sequences at reverse start sites are similar to those of their forward counterparts. The use of DNase I accessibility to define proximal promoter borders revealed that about half of promoters are unidirectional and that these unidirectional promoters are depleted at their upstream edges of reverse core promoter sequences and their associated chromatin features. Divergent transcription is thus not an inherent property of the transcription process, but rather the consequence of the presence of both forward- and reverse-directed core promoters. Overall design: Using 5''-GRO-seq and GRO-seq to determine mechanisms of divergent transcription initiation
Human promoters are intrinsically directional.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Comprehensive functional characterization of cancer-testis antigens defines obligate participation in multiple hallmarks of cancer.
Cell line, Treatment
View Samples