Project description:Topoisomerases are essential for resolving topological problems in the genome, while their function in gene regulation, especially during cellular differentiation, remains unknown. We reveal that the expression of two Topo II isoforms, Top2a and Top2ß, is characteristic of dividing and postmitotic tissues, respectively. In embryonic stem cells, Top2a preferentially binds to promoters embedded in an active chromatin environment. Inhibition of Top2a activity results in misregulation of target gene expression that accompanies accumulation of double-strand breaks. Common targets of Top2a and Top2ß are housekeeping genes while their unique targets are involved in proliferation/pluripotency and neurogenesis, respectively. Moreover, a subset of Top2a targets exhibit bivalent chromatin state that is resolved upon differentiation concomitant with their activation and occupancy by Top2ß, a feature further observed for long genes. These findings suggest that Top2a not only contributes to stem cell transcriptome regulation but may also prime developmental genes for subsequent activation upon differentiation. mRNA profiles of DMSO and ICRF-193 treated mESCs were generated by deep sequencing in triplicates. ICRF-193 is a well established catalytic inhibitor of Topoisomerase II, hence, we used ICRF-193 to the elucidate role of Top2a catalytic activity on transcription by genome wide transcription profiling.
Project description:Topoisomerases are essential for resolving topological problems in the genome, while their function in gene regulation, especially during cellular differentiation, remains unknown. We reveal that the expression of two Topo II isoforms, Top2a and Top2ß, is characteristic of dividing and postmitotic tissues, respectively. In embryonic stem cells, Top2a preferentially binds to promoters embedded in an active chromatin environment. Inhibition of Top2a activity results in misregulation of target gene expression that accompanies accumulation of double-strand breaks. Common targets of Top2a and Top2ß are housekeeping genes while their unique targets are involved in proliferation/pluripotency and neurogenesis, respectively. Moreover, a subset of Top2a targets exhibit bivalent chromatin state that is resolved upon differentiation concomitant with their activation and occupancy by Top2ß, a feature further observed for long genes. These findings suggest that Top2a not only contributes to stem cell transcriptome regulation but may also prime developmental genes for subsequent activation upon differentiation.
Project description:Topoisomerases are essential for resolving topological problems in the genome, while their function in gene regulation, especially during cellular differentiation, remains unknown. We reveal that the expression of two Topo II isoforms, Top2a and Top2ß, is characteristic of dividing and postmitotic tissues, respectively. In embryonic stem cells, Top2a preferentially binds to promoters embedded in an active chromatin environment. Inhibition of Top2a activity results in misregulation of target gene expression that accompanies accumulation of double-strand breaks. Common targets of Top2a and Top2ß are housekeeping genes while their unique targets are involved in proliferation/pluripotency and neurogenesis, respectively. Moreover, a subset of Top2a targets exhibit bivalent chromatin state that is resolved upon differentiation concomitant with their activation and occupancy by Top2ß, a feature further observed for long genes. These findings suggest that Top2a not only contributes to stem cell transcriptome regulation but may also prime developmental genes for subsequent activation upon differentiation.
Project description:Topoisomerases are essential for resolving topological problems in the genome, while their function in gene regulation, especially during cellular differentiation, remains elusive/unknown. We reveal that the expression of two Topo II isoforms, Top2α and Top2β, is characteristic of dividing and postmitotic tissues, respectively. In embryonic stem cells, Top2α preferentially binds to promoters embedded in an active chromatin environment. Inhibition of Top2α activity results in misregulation of target gene expression that accompanies accumulation of double-strand breaks. Common targets of Top2α and Top2β are housekeeping genes while their unique targets are involved in proliferation/pluripotency and neurogenesis (Can we say this as this might be because we are driving neurons from ES cells), respectively. Moreover, a small subset of Top2α targets exhibit bivalent chromatin state that is resolved upon differentiation concomitant with their activation and occupancy by Top2β, a feature further observed for large lengthlong genes. These findings suggest that Top2α not only contributes to stem cell transcriptome regulation but may also prime developmental genes for subsequent activation by Top2β.