title: Direct Visualization of DNA Replication Dynamics in Zebrafish Cells.
abstract: Spatiotemporal regulation of DNA replication in the S-phase nucleus has been extensively studied in mammalian cells because it is tightly coupled with the regulation of other nuclear processes such as transcription. However, little is known about the replication dynamics in nonmammalian cells. Here, we analyzed the DNA replication processes of zebrafish (Danio rerio) cells through the direct visualization of replicating DNA in the nucleus and on DNA fiber molecules isolated from the nucleus. We found that zebrafish chromosomal DNA at the nuclear interior was replicated first, followed by replication of DNA at the nuclear periphery, which is reminiscent of the spatiotemporal regulation of mammalian DNA replication. However, the relative duration of interior DNA replication in zebrafish cells was longer compared to mammalian cells, possibly reflecting zebrafish-specific genomic organization. The rate of replication fork progression and ori-to-ori distance measured by the DNA combing technique were ∼ 1.4 kb/min and 100 kb, respectively, which are comparable to those in mammalian cells. To our knowledge, this is a first report that measures replication dynamics in zebrafish cells.
authors.affiliation: 1 Laboratory of Molecular and Cellular Biology, Department of Life Sciences, Graduate School of Bioresources, Mie University , Tsu, Japan .
authors.forename: Kenji
authors.initials: K
authors.lastname: Kuriya
authors.affiliation: 1 Laboratory of Molecular and Cellular Biology, Department of Life Sciences, Graduate School of Bioresources, Mie University , Tsu, Japan .
authors.forename: Eriko
authors.initials: E
authors.lastname: Higashiyama
authors.affiliation: 2 Laboratory for the Utilization of Aquatic Bioresources, Department of Life Sciences, Graduate School of Bioresources, Mie University , Tsu, Japan .
authors.forename: Eriko
authors.initials: E
authors.lastname: Avşar-Ban
authors.affiliation: 2 Laboratory for the Utilization of Aquatic Bioresources, Department of Life Sciences, Graduate School of Bioresources, Mie University , Tsu, Japan .
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Tamaru
authors.affiliation: 1 Laboratory of Molecular and Cellular Biology, Department of Life Sciences, Graduate School of Bioresources, Mie University , Tsu, Japan .
authors.forename: Shin
authors.initials: S
authors.lastname: Ogata
authors.affiliation: 3 Department of Biochemistry and Proteomics, Graduate School of Medicine, Mie University , Tsu, Japan .
authors.forename: Shin-ichiro
authors.initials: S
authors.lastname: Takebayashi
authors.affiliation: 3 Department of Biochemistry and Proteomics, Graduate School of Medicine, Mie University , Tsu, Japan .
authors.forename: Masato
authors.initials: M
authors.lastname: Ogata
authors.affiliation: 1 Laboratory of Molecular and Cellular Biology, Department of Life Sciences, Graduate School of Bioresources, Mie University , Tsu, Japan .
authors.forename: Katsuzumi
authors.initials: K
authors.lastname: Okumura
mesh_terms: D000818:Animals; D002460:Cell Line; D004247:DNA / Q000502:physiology*; D004261:DNA Replication / Q000502:physiology*; D004912:Erythrocytes; D006801:Humans; D008938:Mitosis / Q000502:physiology; D013045:Species Specificity; D013194:Staining and Labeling; D013997:Time Factors; D015027:Zebrafish / Q000378:metabolism*
chemical_list: D004247:DNA