title: Expression dynamics and functional implications of DNA topoisomerase II beta in the brain.
abstract: Mammalian DNA topoisomerase II beta is a type II DNA topoisomerase that catalyses topological transformations of genomic DNA by the transport of one DNA double helix through another. The II beta enzyme is highly expressed in cells that have undergone the final cell division and committed to differentiate into neuronal cells. The II beta enzyme in the differentiating neuronal cells is located in the nucleoplasm and is actively engaged in its catalytic reaction in vivo. When enzyme action is interfered with a specific inhibitor in vitro, transcriptional induction of a subset of genes fails to occur during neuronal differentiation. Detailed analyses of developing rat cerebellum and the cerebrum of mice with disrupted II beta genes have revealed that DNA topoisomerase II beta is necessary for the developmentally regulated expression of certain genes in cells committed to a neuronal fate after the final division. Herein, we review a dynamic aspect of DNA topoisomerase II beta in the brain with special emphasis on developing cerebellar neurons.
authors.affiliation: Department of Neuroanatomy and Neurobiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan. otsukimi@md.okayama-u.ac.jp
authors.forename: Kimiko M
authors.initials: KM
authors.lastname: Tsutsui
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Sano
authors.forename: Osamu
authors.initials: O
authors.lastname: Hosoya
authors.forename: Ken
authors.initials: K
authors.lastname: Tsutsui
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology*; D002531:Cerebellum / Q000166:cytology* / Q000254:growth & development / Q000378:metabolism; D004250:DNA Topoisomerases, Type II / Q000378:metabolism* / Q000502:physiology; D004268:DNA-Binding Proteins / Q000378:metabolism* / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D009474:Neurons / Q000166:cytology*; D013687:Telencephalon / Q000254:growth & development / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D004250:DNA Topoisomerases, Type II