MeCP2 binding to DNA depends upon hydration at methyl-CpG
Ho, K.L., McNae, I.W., Schmiedeberg, L., Klose, R.J., Bird, A.P., Walkinshaw, M.D.(2008) Mol Cell 29: 525-531
- PubMed: 18313390 
- DOI: https://doi.org/10.1016/j.molcel.2007.12.028
- Primary Citation of Related Structures:  
3C2I - PubMed Abstract: 
MeCP2 is an essential transcriptional repressor that mediates gene silencing through binding to methylated DNA. Binding specificity has been thought to depend on hydrophobic interactions between cytosine methyl groups and a hydrophobic patch within the methyl-CpG-binding domain (MBD). X-ray analysis of a methylated DNA-MBD cocrystal reveals, however, that the methyl groups make contact with a predominantly hydrophilic surface that includes tightly bound water molecules. This suggests that MeCP2 recognizes hydration of the major groove of methylated DNA rather than cytosine methylation per se. The MeCP2-DNA complex also identifies a unique structural role for T158, the residue most commonly mutated in Rett syndrome.
Organizational Affiliation: 
School of Biological Sciences, University of Edinburgh, King's Buildings, Mayfield Road, Edinburgh EH9 3JR, UK.