Regulation of gene expression by nucleosome acetylation

This is an epigenetic regulatory mechanism. Histones are protein complexes containing positively charged amino acids, they bind to negatively charged structures DNA and together form a complex - a nucleosome. The degree of acetylation is partly controlled by DNA methylation, as histone deacetylases are associated with methylated stretches of DNA.
 * Histone acetylases: decondense chromatin, facilitate transcription.
 * Histone deacetylases: cause chromatin condensation, prevent transcription.