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.
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.
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.
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.
Project description:Human infants exhibit innate social behaviors at birth, yet little is understood about the embryonic development of sociality. We screened 1120 known drugs and found that embryonic inhibition of topoisomerase IIα (Top2a) resulted in lasting social deficits in zebrafish. In mice, prenatal Top2 inhibition caused behavioral defects related to core symptoms of autism, including impairments in social interaction and communication. Mutation of Top2a in zebrafish caused downregulation of a set of genes highly enriched for genes associated with autism in humans. Both the Top2a-regulated and autism-associated gene sets possess binding sites for polycomb repressive complex 2 (PRC2), a regulatory complex responsible for H3K27 trimethylation. Moreover, both gene sets are highly enriched for H3K27me3. Inhibition of PRC2 component Ezh2 rescued social deficits caused by Top2 inhibition. Therefore, Top2a is a key component of an evolutionarily conserved pathway that promotes the development of social behavior through PRC2 and H3K27me3.
Project description:Tetraploid cells are more resistant against genotoxic stress (irradiation, platinum compounds, topoisomerase inhibitors) than their diploid precursors. Here, we studied the effect of cisplatin and/or Chk1 inhibition on the transcriptome of diploid and tetraploid HCT116 cells
Project description:Many anti-cancer drugs induce DNA breaks to eliminate tumor cells. The anthracycline topoisomerase II inhibitors can also evict histones. We performed a genome-wide high-resolution mapping of chemotherapeutic effects of various topoisomerase I and II inhibitors. We show that different drugs target different types of chromatin for induction of DNA damage and histone eviction. Topoisomerase inhibitors topotecan and etoposide similarly target transcriptionally active chromatin for DNA damage. Daunorubicin induces DNA breaks and evicts histones in active chromatin, thus quenching local DNA damage response. The analog aclarubicin evicts histones in H3K27me3-marked heterochromatin. These results can guide rational treatment decisions regarding these genome manipulating anti-cancer drugs. FAIRE-seq and g-H2AX ChIP-seq were performed on K562 cells after drug exposure