Co-ordinate inhibiton of autism candidate genes by topoisomerase inhibitors [array]
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE43899 | GEO | 2013/08/30
SECONDARY ACCESSION(S): PRJNA188087
REPOSITORIES: GEO
Similar Datasets
Project description:Topoisomerases are necessary for the expression of neurodevelopmental genes, and are mutated in some patients with autism spectrum disorder (ASD). We have studied the effects of inhibitors of Topoisomerase 1 (Top1) and Topoisomerase 2 (Top2) enzymes on mouse cortical neurons. We find that topoisomerases selectively inhibit long genes (>100kb), with little effect on all other gene expression. Using ChIPseq against RNA Polymerase II (Pol2) we show that the Top1 inhibitor topotecan blocks transcriptional elongation of long genes specifically. Many of the genes inhibited by topotecan are candidate ASD genes, leading us to propose that topoisomerase inhibition might contribute to ASD pathology. 9 experiments, gene expression measured by Affymetrix microarray. 1) cultured mouse cortical neurons treated with 300nM topotecan vs vehicle-treated controls 2) cultured mouse neurons treated with 1uM topotecan vs vehicle-treated controls 3) cultured mouse cortical neurons treated with 3uM ICRF-193 vs vehicle-treated controls. 4) cultured mouse cortical neurons treated with 10 uM irinotecan vs vehicle-treated controls. 5) cultured mouse cortical neurons treated with 3-1000 nM topotecan vs vehicle treated controls 6) cultured mouse cortical neurons treated with lentivirus expressing shRNA against Top1 and Top2b vs scrambled shRNA controls 7) cultured mouse cortical neurons treated with DRB vs vehicle-treated controls 8) cultured mouse cortical neurons treated with hydrogen peroxide or paraquat vs vehicle-treated controls 9) cultured mouse cortical neurons treated with topotecan with or without subsequent drug washout, vs vehicle-treated controls.
2013-08-30 | E-GEOD-43899 | biostudies-arrayexpress
Project description:Topoisomerases are necessary for the expression of neurodevelopmental genes, and are mutated in some patients with autism spectrum disorder (ASD). We have studied the effects of inhibitors of Topoisomerase 1 (Top1) and Topoisomerase 2 (Top2) enzymes on mouse cortical neurons. We find that topoisomerases selectively inhibit long genes (>100kb), with little effect on all other gene expression. Using ChIPseq against RNA Polymerase II (Pol2) we show that the Top1 inhibitor topotecan blocks transcriptional elongation of long genes specifically. Many of the genes inhibited by topotecan are candidate ASD genes, leading us to propose that topoisomerase inhibition might contribute to ASD pathology. [Mouse] 5 biological replicates of transcriptome sequencing (RNAseq) from topotecan treated neurons and vehicle treated controls; Pol2 ChIPseq of topotecan and vehicle treated neurons [Human] Transcriptome sequencing (RNAseq) from topotecan treated neurons and vehicle treated control.
2013-08-30 | E-GEOD-43526 | biostudies-arrayexpress
Project description:Topoisomerases are necessary for the expression of neurodevelopmental genes, and are mutated in some patients with autism spectrum disorder (ASD). We have studied the effects of inhibitors of Topoisomerase 1 (Top1) and Topoisomerase 2 (Top2) enzymes on mouse cortical neurons. We find that topoisomerases selectively inhibit long genes (>100kb), with little effect on all other gene expression. Using ChIPseq against RNA Polymerase II (Pol2) we show that the Top1 inhibitor topotecan blocks transcriptional elongation of long genes specifically. Many of the genes inhibited by topotecan are candidate ASD genes, leading us to propose that topoisomerase inhibition might contribute to ASD pathology.
2013-08-30 | GSE43526 | GEO
Project description:DNA topoisomerases are known to promote transcription in prokaryotes by removing excessive DNA supercoils produced during elongation. However, it is unclear how topoisomerases in eukaryotes are recruited and function in the transcription pathway in the context of nucleosomes. To address this problem we present high-resolution genome wide maps of one of the major eukaryotic topoisomerases, Topoisomerase II (Top2) and nucleosomes in the budding yeast, Saccharomyces cerevisiae. Our data indicate that at promoters Top2 binds primarily to DNA that is nucleosome free. However, while nucleosome loss enables Top2 occupancy the opposite is not the case and the loss of Top2 has little effect on nucleosome density. We also find that Top2 is involved in transcription. Not only is Top2 enriched at highly transcribed genes but Top2 is required redundantly with Top1 for optimal recruitment of RNA polymerase II at their promoters. These findings and the examination of candidate activated genes suggest that nucleosome loss induced by nucleosome remodeling factors during gene activation enable Top2 binding which in turn acts redundantly with Top1 to enhance recruitment of RNA polymerase II.
2011-08-01 | GSE22626 | GEO
Project description:During meiotic prophase, concurrent transcription, recombination, and chromosome synapsis place substantial topological strain on chromosomal DNA, but the role of topoisomerases in this context remains poorly defined. Here, we analyzed the roles topoisomerases I and II (Top1 and Top2) during meiotic prophase in Saccharomyces cerevisiae. We show that both topoisomerases accumulate primarily in promoter-containing intergenic regions of actively transcribing genes, including many meiotic double-strand break (DSB) hotspots. Despite the comparable binding patterns, top1 and top2 mutations have different effects on meiotic recombination. TOP1 disruption delays DSB induction and shortens the window of DSB accumulation by an unknown mechanism. By contrast, temperature-sensitive top2-1 mutants exhibit a marked delay in meiotic chromosome remodeling and elevated DSB signals on synapsed chromosomes. The problems in chromosome remodeling were linked to altered Top2 binding patterns rather than a loss of Top2 catalytic activity and stemmed from a defect in recruiting the chromosome remodeler Pch2/TRIP13 to synapsed chromosomes. No chromosomal defects were observed in the absence of TOP1. Our results imply independent roles for topoisomerases I and II in modulating meiotic chromosome structure and recombination.
2020-03-06 | GSE131994 | GEO
Project description:Inhibitors of DNA topoisomerase I (TOP1), an enzyme relieving torsional stress of DNA by generating transient single-strand breaks, are clinically used to treat ovarian cancer, small cell lung cancer and cervical cancer. As torsional stress is generated by replication and transcription we tested the effects of clinically used TOP1 inhibitors Topotecan and SN-38 on TNF-induced gene expression. RNA-seq experiments showed that inhibition of TOP1 activity interfered with the vast majority of TNF-triggered genes, while interference with TOP2 activity had only a minor impact. TOP1 inhibition affected the expression of early and late induced genes and the relative strength of gene induction played no role in the sensitivity to TOP1 interfering drugs. These data raise the possibility that the inhibition of inflammatory gene expression contributes to the increased risk of infection seen in some patients treated with TOP1 inhibtors.
2019-06-22 | GSE128798 | GEO
Project description:Topoisomerase 1 (TOP1) inhibitors, including camptothecin and topotecan, covalently trap TOP1 on DNA, creating cleavage complexes (cc’s) that must be resolved before gene transcription and DNA replication can proceed. We previously found that topotecan reduces the expression of long (>100 kb) genes and unsilences the paternal allele of Ube3a in neurons. Here, we sought to evaluate overlap between TOP1cc-dependent and -independent gene regulation in neurons. To do this, we utilized Top1 conditional knockout mice, Top1 knockdown, the CRISPR-Cas9 system to delete Top1, TOP1 catalytic inhibitors that do not generate TOP1cc’s, and a TOP1 mutation (T718A) that stabilizes TOP1cc’s. We found that topotecan treatment significantly alters the expression of many more genes, including long neuronal genes, immediate early genes, and paternal Ube3a, when compared to Top1 deletion. Our data show that topotecan has a stronger effect on neuronal transcription than Top1 deletion, and identifies TOP1cc-dependent and -independent contributions to gene expression.
2016-05-27 | GSE79951 | GEO
Project description:Replication forks temporarily or terminally pause at hundreds of hard-to-replicate regions around the genome. A conserved pair of budding yeast replisome components Tof1-Csm3 (fission yeast Swi1-Swi3 and human TIMELESS-TIPIN) acts as a ‘molecular brake’ and promotes fork slowdown at proteinaceous replication fork barriers (RFBs), while the accessory helicase Rrm3 assists the replisome in removing protein obstacles. Here we show that Tof1-Csm3 complex promotes fork pausing independently of Rrm3 helicase by recruiting topoisomerase I (Top1) to the replisome. Topoisomerase II (Top2) partially compensates for the pausing decrease in cells when Top1 is lost from the replisome. The C-terminus of Tof1 is specifically required for Top1 recruitment to the replisome and fork pausing but not for DNA replication checkpoint (DRC) activation. We propose that forks pause at proteinaceous RFBs through a ‘sTOP’ mechanism (‘slowing down with TOPoisomerases I-II’), which we show also contributes to protecting cells from topoisomerase-blocking agents.
2019-11-07 | GSE140034 | GEO
Project description:DNA topoisomerase-2 and high mobility group protein Hmo1 are known to regulate chromatin architecture by regulating gene boundaries. Here we report how these proteins affect global RNA level after inactivation of Top2 and Hmo1. Our data indicate that inactivating Hmo1 has a drastic effect on transcription levels of 20% yeast genes, however, this phenomenon can slightly be rescued by inactivating Top2 functions. Also, we study the Top2 and Top1 role in nucleosome architecture with and without expressing E.coli TopA. In top2-1;top1∆ condition with TopA expressed, it affects the nucleosome occupancy at the global level compared with top2-1;top1∆-Control plasmid. The ChIA-PET (Chromatin interaction analysis by paired-end tag sequencing) method is used to address whether a specific protein is engaged in the chromosomal interactions. Epitope tagged Top2 protein is used as probe in ChIA-PET experiments to map Top2 mediated chromatin-chromatin interactions.
2018-07-02 | GSE114444 | GEO
Project description:DNA topoisomerases solve topological problems during chromosome metabolism. We investigated where and when Top1 and Top2 are recruited on replicating chromosomes and how their inactivation affects fork integrity and DNA damage checkpoint activation. We show that, in the context of replicating chromatin, Top1 and Top2 act within a 600 bp region spanning the moving forks. Top2 exhibits additional S-phase clusters at specific intergenic loci, mostly containing promoters. TOP1 ablation does not affect fork progression and stability and does not cause activation of the Rad53 checkpoint kinase. top2 mutants accumulate sister chromatid junctions in S phase without affecting fork progression and activate Rad53 at the M/G1 transition. top1 top2 double mutants exhibit fork block and processing, and phosphorylation of Rad53 and γH2A in S phase. The exonuclease Exo1 influences fork processing and DNA damage checkpoint activation in top1 top2 mutants. Our data are consistent with a coordinated action of Top1 and Top2 in counteracting the accumulation of torsional stress and sister chromatid entanglement at replication forks, thus preventing the diffusion of topological changes along large chromosomal regions. A failure in resolving fork-related topological constrains during S phase may therefore result in abnormal chromosome transitions, DNA damage checkpoint activation and chromosome breakage during segregation. Keywords: ChIP-chip analysis
2007-08-01 | GSE8305 | GEO