Figure 2.

Schematic representation of the main histone modification processes. Both acetylation and methylation positively and negatively regulate gene transcription according to the methylated or acetylated residue (up). Several drugs have been designed to allow chromatin remodeling by the inhibition of BET, HDAC or HMT proteins that condense chromatin and hamper transcription (down). Histones acetylation and cytosines unmethylation will result in an open chromatin structure and gene transcription is active. BET: bromodomain and extra-terminal motif (BET) proteins. HDAC: histone deacetylases. HMT: histone methyltransferase. DNMTs: DNA methyltransferases. HAT: histone acetyltransferase. HDM: histone demethylase.