In addition, we have increased the number of different database identifiers supported by PANTHER tools and in searches of the PANTHER database. Previously, for genes only identifiers from NCBI Entrez Gene (17) or FlyBase (15) were supported; for proteins only RefSeq (24) or FlyBase identifiers. In PANTHER 7, we now also support identifiers from Ensembl (23), model organism databases, the International Protein Index (IPI) (25) and UniProt (18). All of these identifiers are obtained through the mapping files provided by UniProt (ftp://ftp.uniprot.org/pub/databases/uniprot/current_release/knowledgebase/idmapping/).