title: Uhrf1-dependent H3K23 ubiquitylation couples maintenance DNA methylation and replication.
abstract: Faithful propagation of DNA methylation patterns during DNA replication is critical for maintaining cellular phenotypes of individual differentiated cells. Although it is well established that Uhrf1 (ubiquitin-like with PHD and ring finger domains 1; also known as Np95 and ICBP90) specifically binds to hemi-methylated DNA through its SRA (SET and RING finger associated) domain and has an essential role in maintenance of DNA methylation by recruiting Dnmt1 to hemi-methylated DNA sites, the mechanism by which Uhrf1 coordinates the maintenance of DNA methylation and DNA replication is largely unknown. Here we show that Uhrf1-dependent histone H3 ubiquitylation has a prerequisite role in the maintenance DNA methylation. Using Xenopus egg extracts, we successfully reproduce maintenance DNA methylation in vitro. Dnmt1 depletion results in a marked accumulation of Uhrf1-dependent ubiquitylation of histone H3 at lysine 23. Dnmt1 preferentially associates with ubiquitylated H3 in vitro though a region previously identified as a replication foci targeting sequence. The RING finger mutant of Uhrf1 fails to recruit Dnmt1 to DNA replication sites and maintain DNA methylation in mammalian cultured cells. Our findings represent the first evidence, to our knowledge, of the mechanistic link between DNA methylation and DNA replication through histone H3 ubiquitylation.
authors.affiliation: Department of Cell Biology, Graduate School of Medical Sciences, Nagoya City University, Nagoya 467-8601, Japan. anishiya@med.nagoya-cu.ac.jp
authors.forename: Atsuya
authors.initials: A
authors.lastname: Nishiyama
authors.forename: Luna
authors.initials: L
authors.lastname: Yamaguchi
authors.forename: Jafar
authors.initials: J
authors.lastname: Sharif
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Johmura
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kawamura
authors.forename: Keiko
authors.initials: K
authors.lastname: Nakanishi
authors.forename: Shintaro
authors.initials: S
authors.lastname: Shimamura
authors.forename: Kyohei
authors.initials: K
authors.lastname: Arita
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Kodama
authors.forename: Fuyuki
authors.initials: F
authors.lastname: Ishikawa
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Koseki
authors.forename: Makoto
authors.initials: M
authors.lastname: Nakanishi
mesh_terms: D000818:Animals; D002460:Cell Line; D019175:DNA Methylation / Q000235:genetics / Q000502:physiology*; D004261:DNA Replication / Q000235:genetics / Q000502:physiology*; D057809:HEK293 Cells; D006367:HeLa Cells; D006657:Histones / Q000378:metabolism*; D006801:Humans; D051379:Mice; D010063:Ovum / Q000737:chemistry; D011485:Protein Binding; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism*; D014982:Xenopus laevis / Q000235:genetics* / Q000378:metabolism*
chemical_list: D006657:Histones; D029867:Xenopus Proteins; D044767:Ubiquitin-Protein Ligases; C584137:Uhrf1 protein, Xenopus