Characterisation of site-biased DNA methyltransferases: specificity, affinity and subsite relationships.

ABSTRACT: DNA methylation is now seen as a primary signal in the cell for mediating transcriptional repression through chromatin formation. The construction and evaluation of enzymes capable of influencing this process in vivo is therefore of significant interest. We have fused the C5-cytosine DNA methyltransferases, M.HhaI and M.HpaII, which both methylate 4 bp sequences containing a CpG dinucleotide, to a three zinc finger protein recognising a 9 bp DNA sequence. DNA methylation analyses demonstrate specific DNA methylation by both enzymes at target sites comprising adjacent methyltransferase and zinc finger subsites, targeted M.HpaII being the most specific. Binding analysis of the targeted M.HpaII enzyme reveals an 8-fold preference for binding to its target site, compared to binding to a zinc f

SUBMITTER: McNamara AR 

PROVIDER: S-EPMC137423 | biostudies-literature | 2002 Sep

REPOSITORIES: biostudies-literature