The cellular component ontology describes locations, at the levels of subcellular structures and macromolecular complexes. Examples of cellular components include 'nuclear inner membrane', with the synonym 'inner envelope', and the 'ubiquitin ligase complex', with several subtypes of these complexes represented.
This page documents the file formats used to store gene associations (annotations), data capturing the attributes of gene products using terms from the Gene Ontology. For more general information on annotation, please see the GO annotation guide.
Annotation data is submitted to the GO Consortium in the form of gene association files, or GAFs. The following document lays out the format specification for GAF 1.0; for the newer GAF 2.0 file syntax, please see the GAF 2.0 file format guide.
The GO File Format Guide documents the structure and syntax of the files available on the GO website, to assist users who need to read, write parsers for, or create these files. The following file formats are documented separately:
The GO database is a relational database comprised of the GO ontologies as well as the annotations of genes and gene products to terms in the those ontologies. Housing both the ontologies and the annotations in a single database allows powerful queries of the annotations using the ontology. The GO database is the source of all data available through the legacy AmiGO 1.8 browser and search engine.
Annotation is the process of assigning GO terms to gene products. The annotation data in the GO database is contributed by members of the GO Consortium, and the Consortium is continuously encouraging new groups to start contributing their annotations. The list of links below offer details on the GO annotation policies and the annotation process, as well as direct users to other pages of interest on GO annotation conventions, the standard operating procedures used by some consortium members, and the GO annotation file format guide.