0 1 0 http://purl.obolibrary.org/obo/MOD_02028 iTRAQ4plex reporter+balance reagent acylated residue, average mass modification 'iTRAQ4plex reporter+balance reagent acylated residue, average mass modification' SubClassOf 'iTRAQ4plex reporter+balance reagent N-acylated residue' 'iTRAQ4plex reporter+balance reagent acylated residue, average mass modification' SubClassOf 'modifications with monoisotopic mass differences that are nominally equal at a resolution below 0.1 Da' 'iTRAQ4plex reporter+balance reagent acylated residue, average mass modification' SubClassOf 'isotope tagged reagent acylated residue' 'iTRAQ4plex reporter+balance reagent acylated residue, average mass modification' SubClassOf 'isotope tagged reagent derivatized residue'