Proteins acting as histones, histone variants or protamines;
Proteins performing post-translational modifications of histones or recognizing such modifications (histone modification ‘writers’, ‘erasers’ or ‘readers’);
Proteins changing the general structure of chromatin (performing chromatin remodeling), including Proteins that move, eject or restructure nucleosomes (ATP-dependent chromatin remodelers) and proteins that incorporate histone variants into the nucleosomes.
Proteins assisting histone folding and assembly;
Proteins acting upon modifications of DNA or RNA in such a way that it affects gene expression, but not through RNA processing;
Protein cofactors forming complexes with epigenetic factors, where complex formation is important for the activity.