Before revision:  The compilation of 9 protein-protein interaction and 8 subcellular localization datasets had 4 curation steps including a manually built, comprehensive hierarchical structure of more than 1,600 subcellular localizations.
After revision:  The compilation of 9 protein-protein interaction and eight subcellular localization data sets had four curation steps including a manually built, comprehensive hierarchical structure of more than 1,600 subcellular localizations.