title: AUF1 cell cycle variations define genomic DNA methylation by regulation of DNMT1 mRNA stability.
abstract: DNA methylation is a major determinant of epigenetic inheritance. DNA methyltransferase 1 (DNMT1) is the enzyme responsible for the maintenance of DNA methylation patterns during cell division, and deregulated expression of DNMT1 leads to cellular transformation. We show herein that AU-rich element/poly(U)-binding/degradation factor 1 (AUF1)/heterogeneous nuclear ribonucleoprotein D interacts with an AU-rich conserved element in the 3' untranslated region of the DNMT1 mRNA and targets it for destabilization by the exosome. AUF1 protein levels are regulated by the cell cycle by the proteasome, resulting in cell cycle-specific destabilization of DNMT1 mRNA. AUF1 knock down leads to increased DNMT1 expression and modifications of cell cycle kinetics, increased DNA methyltransferase activity, and genome hypermethylation. Concurrent AUF1 and DNMT1 knock down abolishes this effect, suggesting that the effects of AUF1 knock down on the cell cycle are mediated at least in part by DNMT1. In this study, we demonstrate a link between AUF1, the RNA degradation machinery, and maintenance of the epigenetic integrity of the cell.
authors.affiliation: Department of Pharmacology and Therapeutics, McGill University, 3655 Sir William Osler Promenade, Montreal, Quebec H3G 1Y6, Canada.
authors.forename: Jerome
authors.initials: J
authors.lastname: Torrisani
authors.forename: Alexander
authors.initials: A
authors.lastname: Unterberger
authors.forename: Sachin R
authors.initials: SR
authors.lastname: Tendulkar
authors.forename: Keisuke
authors.initials: K
authors.lastname: Shikimi
authors.forename: Moshe
authors.initials: M
authors.lastname: Szyf
mesh_terms: D020413:3' Untranslated Regions; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002453:Cell Cycle; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000378:metabolism / Q000502:physiology*; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005786:Gene Expression Regulation; D006367:HeLa Cells; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data
chemical_list: D020413:3' Untranslated Regions; C000630986:HNRNPD protein, human; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D; C000630987:Hnrpd protein, mouse; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; C000619380:DNMT1 protein, human; C000619381:Dnmt1 protein, mouse