Preferential methylation of unmethylated DNA by Mammalian de novo DNA methyltransferase Dnmt3a
- PMID: 11821381
- DOI: 10.1074/jbc.M106590200
Preferential methylation of unmethylated DNA by Mammalian de novo DNA methyltransferase Dnmt3a
Abstract
DNA methylation is an epigenetic modification of DNA. There are currently three catalytically active mammalian DNA methyltransferases, DNMT1, -3a, and -3b. DNMT1 has been shown to have a preference for hemimethylated DNA and has therefore been termed the maintenance methyltransferase. Although previous studies on DNMT3a and -3b revealed that they act as functional enzymes during development, there is little biochemical evidence about how new methylation patterns are established and maintained. To study this mechanism we have cloned and expressed Dnmt3a using a baculovirus expression system. The substrate specificity of Dnmt3a and molecular mechanism of its methylation reaction were then analyzed using a novel and highly reproducible assay. We report here that Dnmt3a is a true de novo methyltransferase that prefers unmethylated DNA substrates more than 3-fold to hemimethylated DNA. Furthermore, Dnmt3a binds DNA nonspecifically, regardless of the presence of CpG dinucleotides in the DNA substrate. Kinetic analysis supports an Ordered Bi Bi mechanism for Dnmt3a, where DNA binds first, followed by S-adenosyl-l-methionine.
Similar articles
-
Enzymatic properties of recombinant Dnmt3a DNA methyltransferase from mouse: the enzyme modifies DNA in a non-processive manner and also methylates non-CpG [correction of non-CpA] sites.J Mol Biol. 2001 Jun 22;309(5):1201-8. doi: 10.1006/jmbi.2001.4710. J Mol Biol. 2001. PMID: 11399089
-
Murine de novo methyltransferase Dnmt3a demonstrates strand asymmetry and site preference in the methylation of DNA in vitro.Mol Cell Biol. 2002 Feb;22(3):704-23. doi: 10.1128/MCB.22.3.704-723.2002. Mol Cell Biol. 2002. PMID: 11784849 Free PMC article.
-
Auto-methylation of the mouse DNA-(cytosine C5)-methyltransferase Dnmt3a at its active site cysteine residue.FEBS J. 2011 Jun;278(12):2055-63. doi: 10.1111/j.1742-4658.2011.08121.x. Epub 2011 May 19. FEBS J. 2011. PMID: 21481189
-
Mammalian cytosine DNA methyltransferase Dnmt1: enzymatic mechanism, novel mechanism-based inhibitors, and RNA-directed DNA methylation.Curr Med Chem. 2008;15(1):92-106. doi: 10.2174/092986708783330700. Curr Med Chem. 2008. PMID: 18220765 Review.
-
DNA Methyltransferases in Mammalian Oocytes.Results Probl Cell Differ. 2017;63:211-222. doi: 10.1007/978-3-319-60855-6_10. Results Probl Cell Differ. 2017. PMID: 28779320 Review.
Cited by
-
Co-operation and communication between the human maintenance and de novo DNA (cytosine-5) methyltransferases.EMBO J. 2002 Aug 1;21(15):4183-95. doi: 10.1093/emboj/cdf401. EMBO J. 2002. PMID: 12145218 Free PMC article.
-
Distribution, recognition and regulation of non-CpG methylation in the adult mammalian brain.Nat Neurosci. 2014 Feb;17(2):215-22. doi: 10.1038/nn.3607. Epub 2013 Dec 22. Nat Neurosci. 2014. PMID: 24362762 Free PMC article.
-
CXXC finger protein 1 contains redundant functional domains that support embryonic stem cell cytosine methylation, histone methylation, and differentiation.Mol Cell Biol. 2009 Jul;29(14):3817-31. doi: 10.1128/MCB.00243-09. Epub 2009 May 11. Mol Cell Biol. 2009. PMID: 19433449 Free PMC article.
-
SIRT1 deacetylates the DNA methyltransferase 1 (DNMT1) protein and alters its activities.Mol Cell Biol. 2011 Dec;31(23):4720-34. doi: 10.1128/MCB.06147-11. Epub 2011 Sep 26. Mol Cell Biol. 2011. PMID: 21947282 Free PMC article.
-
Selective anchoring of DNA methyltransferases 3A and 3B to nucleosomes containing methylated DNA.Mol Cell Biol. 2009 Oct;29(19):5366-76. doi: 10.1128/MCB.00484-09. Epub 2009 Jul 20. Mol Cell Biol. 2009. PMID: 19620278 Free PMC article.
Publication types
MeSH terms
Substances
Grants and funding
LinkOut - more resources
Full Text Sources
Other Literature Sources
Molecular Biology Databases
Miscellaneous
