This is a worked example of having an extension ontology from INOH.
The point is to add two properties to link pathways or pathway steps: MOLECULAR-VARIATION and HOMOLOGOUS-EVENT.
Then, as an example
MI0007326_Cleavage_of_Notch_in_Delta_complex_by_ADAMS2_cleavage_
is linked to (via HOMOLOGOUS-EVENT)
MI0007409_Cleavage_of_Notch_in_Delta_complex_by_ADAMS2_cleavage_Drosophila_0 and MI0007460_Cleavage_of_Notch1_in_DLL1_complex_by_TACES2_cleavage_Mammal_0
and
MI0007335_Cleavage_of_Notch_in_DSL_complex_by_ADAMS2_cleavage_0
is linked to (vi MOLECULAR-VARIATION)
MI0007326_Cleavage_of_Notch_in_Delta_complex_by_ADAMS2_cleavage_0 MI0007321_Cleavage_of_Notch_in_Serrate_Jagged_complex_by_ADAMS2_cleavage_0
Here's are the important bits.
The part of the main file that imports the extension file is this:
<owl:Ontology rdf:about="">
<owl:imports rdf:resource="
http://www.biopax.org/release/biopax-level2.owl"/> <owl:imports> <owl:Ontology rdf:about="
file:///Users/alanr/Desktop/BioPAX:OBO/MV_HE_AlanProposal/inoh-MV-HE-fixed.owl"> <bp:IMPORT-TYPE rdf:datatype="&xsd;string">Extension</bp:IMPORT-TYPE>
</owl:Ontology>
</owl:imports>
</owl:Ontology>
This is also in the main file, but should be in the biopax specification. Though it doesn't hurt to be there.
Documentation from Ken
attachment:meetingINOH_BioPAX_StatesAndGenerics_061106.doc