Histones, proteins that form a cylindrical tuna-can-like structure, act as a scaffold around which DNA coils. Histone deacetylases, as their name implies, remove acetyl groups from the histone proteins. The resulting chemical changes induce structural realignments that could trigger or repress gene transcription. Meanwhile, DNA methylation leads to gene silencing. The fact that the two functions are wrapped in the same complex provides an intriguing mechanism for how genes get silenced.
University of Edinburgh geneticist Adrian Bird and his team approached the problem from the perspective of methylated DNA, while Paul A. Wade, assistant professor in the department of pathology and laboratory medicine at the Emory University School of Medicine in Atlanta, and colleagues began with histone deacetyl-ase activity. Despite the different thought processes, the results of both efforts reached the same conclusion: binding to methylated DNA is directly linked to histone deacetylases that restructure the chromatin and dampen transcription. ...
