Structure of Frames in a PGDB. A) Frames describe objects in the database. Slots contain information about the frame object, and annotations contain meta-information about slot information. B) a protein is represented by a frame in the database. Examples of slots which describe the protein include the protein name, molecular weight, and GO-Term assignments. Annotations of the GO term information include citations, evidence codes, and information on the person who curated this GO term assignment.