Immunogen sequence: IHQALNSDPT DVAALRRMAI SEGGLLTDEI RRKVWPKLLN VNANDPPPIS GKNLRQMSKD YQQVLLDVRR SLRRFPPGM Highest antigen sequence identity to the following orthologs: Mouse - 86%, Rat - 89%. GTPase-activating protein specific for Rab1 and Rab2 small GT