Protein-protein interactions by database.

BioGRID had 337 interactions between the set of 56 proteins. Of the 5 databases, BioGRID contained the most edges, with high coverage of interactions in the other 4 databases. The interactions missing from BioGRID did not arise due to missed references (except for 3 studies of functional rather than physical associations) but due to missed interactions in the same references. The other 4 databases contained a total of 69 interactions not present in BioGRID, and 52 not present in our original database that had been augmented by added edges and through curation of the SH3/PRD and kinase references. Of these 52 interactions, three were removed for erroneous citations, 20 were found only through functional association, and therefore removed, and the remainder were observed in only a single probe of physical interactions.