Mammalian DNA methyltransferases.

Mammalian DNA methyltransferases.

DNA methylation is an epigenetic process affecting gene expression and chromatin organization. It can heritably silence or activate transcription of genes without any change in their nucleotide sequences, and for a long time was not recognized as an important regulatory mechanism. However, during the recent years it has been shown that improper methylation, especially hypermethylation of promot...

Mammalian DNA methyltransferases show different subnuclear distributions.

In mammalian cells, DNA methylation patterns are precisely maintained after DNA replication with defined changes occurring during development. The major DNA methyltransferase (Dnmt1) is associated with nuclear replication sites during S-phase, which is consistent with a role in maintenance methylation. The subcellular distribution of the recently discovered de novo DNA methyltransferases, Dnmt3...

Regulation of mammalian DNA methyltransferases: a route to new mechanisms.

DNA methyltransferases (DNMTs) establish and maintain DNA methylation patterns at specific regions of the genome, thereby contributing to gene regulation. It is becoming evident that an intricate web of pathways target DNMTs to these genomic regions. Here, we review the understanding of these regulatory mechanisms and provide an overview of the new findings, emphasizing the emerging scenario in...

Allosteric control of mammalian DNA methyltransferases – a new regulatory paradigm

In mammals, DNA methylation is introduced by the DNMT1, DNMT3A and DNMT3B methyltransferases, which are all large multi-domain proteins containing a catalytic C-terminal domain and an N-terminal part with regulatory functions. Recently, two novel regulatory principles of DNMTs were uncovered. It was shown that their catalytic activity is under allosteric control of N-terminal domains with autoi...

Bifunctional Prokaryotic DNA-Methyltransferases