title: Targeted reduction of the DNA methylation level with 5-azacytidine promotes excision of the medaka fish Tol2 transposable element.
abstract: The Tol2 element of the medaka fish Oryzias latipes is a member of the hAT (hobo/Activator/Tam3) transposable element family. There is evidence for rapid expansion in the genome and throughout the species in the past but a high spontaneous transposition rate is not observed with current fish materials, suggesting that the Tol2 element and its host species have already acquired an interactive mechanism to control the transposition frequency. DNA methylation is a possible contributing factor, given its involvement with many other transposable elements. We therefore soaked embryos in 5-azacytidine, a reagent that causes reduction in the DNA methylation level, and examined amounts of PCR products reflecting the somatic excision frequency, obtaining direct evidence that exposure promotes Tol2 excision. Our results thus suggest that methylation of the genome DNA is a factor included in the putative mechanisms of control of transposition of the Tol2 element.
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan.
authors.forename: Atsuo
authors.initials: A
authors.lastname: Iida
authors.forename: Atsuko
authors.initials: A
authors.lastname: Shimada
authors.forename: Akihiro
authors.initials: A
authors.lastname: Shima
authors.forename: Naofumi
authors.initials: N
authors.lastname: Takamatsu
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hori
authors.forename: Kosei
authors.initials: K
authors.lastname: Takeuchi
authors.forename: Akihiko
authors.initials: A
authors.lastname: Koga
mesh_terms: D000818:Animals; D001374:Azacitidine / Q000494:pharmacology*; D019175:DNA Methylation / Q000187:drug effects*; D004251:DNA Transposable Elements / Q000187:drug effects; D004625:Embryo, Nonmammalian / Q000187:drug effects / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D008957:Models, Genetic; D009990:Oryzias / Q000196:embryology / Q000235:genetics* / Q000378:metabolism; D019895:Transposases / Q000378:metabolism
chemical_list: D004251:DNA Transposable Elements; D019895:Transposases; D001374:Azacitidine