has_quality epigenetically_modified post_translationally_modified_region histone_modification Histone modification is a post translationally modified region whereby residues of the histone protein are modified by methylation, acetylation, phosphorylation, ubiquitination, sumoylation, citrullination, or ADP-ribosylation. 2010-03-31T10:22:08Z kareneilbeck sequence histone modification histone modification site SO:0001700 epigenetically_modified_region