Fig 2. Ontology map for sorghum gene association to multiple drought related terms.

The figure shows sorghum genes directly and transitively associated to multiple drought related terms based on functional ontologies. The information from EO, TO, GRO, PO and GO was used to investigate sorghum genes and orthologs in rice and maize associated with stress response. The map represents sorghum specific features for displaying class hierarchy against the ontologies under consideration and the orthologous genes from maize and rice. The hierarchical structure was designed to show multiparental relationships of sorghum genes with different ontology categories without including direct class hierarchy between maize or rice genes to the ontologies. This reveals the occurrence of multi-stress responsive sorghum specific genes and orthologous groups which are associated with GO cellular components for their localization. While the molecular functions and the biological processes of the sorghum specific genes and the orthologs are conserved, the ontology supports all these biological realities.