DNA methyltransferases and methyl-binding proteins of mammals

DNA methyltransferases and methyl-binding proteins of mammals.

In mammals, DNA methylation, characterized by the transfer of the methyl group from S-adenosylmethionines to a base (mainly referred to cytosine), acts as a major epigenetic modification. In parallel to DNA sequences arrangement, modification of methylation to DNA sequences has far-reaching influence on biological functions and activities, for it involves controlling gene transcription, regulat...

The DNA methyltransferases of mammals.

The biological significance of 5-methylcytosine was in doubt for many years, but is no longer. Through targeted mutagenesis in mice it has been learnt that every protein shown by biochemical tests to be involved in the establishment, maintenance or interpretation of genomic methylation patterns is encoded by an essential gene. A human genetic disorder (ICF syndrome) has recently been shown to b...

Role of De Novo DNA Methyltransferases and Methyl C-binding Proteins in Gene Silencing in a Rat Hepatoma

Role of de novo DNA methyltransferases and methyl CpG-binding proteins in gene silencing in a rat hepatoma.

The expression of metallothionein-I (MT-I), a known antioxidant, was suppressed in a transplanted rat hepatoma because of promoter methylation and was induced by heavy metals only after demethylation by 5-azacytidine (5-AzaC). Treatment of the tumor-bearing rats with 5-AzaC resulted in significant regression of the hepatoma. When the inhibitor-treated tumor was allowed to grow in a new host, MT...

Recognition of methylated DNA through methyl-CpG binding domain proteins

DNA methylation is a key regulatory control route in epigenetics, involving gene silencing and chromosome inactivation. It has been recognized that methyl-CpG binding domain (MBD) proteins play an important role in interpreting the genetic information encoded by methylated DNA (mDNA). Although the function of MBD proteins has attracted considerable attention and is well characterized, the mecha...