Effects of DNA methylation on DNA-binding proteins and gene expression.

DNA methyltransferase is needed for normal development, perhaps because DNA methylation plays a part in the control of gene activity. It is clear that the methylation of promoters often leads to repression of transcription. Studies of the mechanism suggest that repression may either result from the direct effects of methylation on transcription factors, or may be indirectly caused by repressor proteins that bind to methylated DNA. Current evidence suggests that both mechanisms can be involved.