Anti-ABR activator of RhoGEF and GTPase antibodies are used for the immunodetection of the protein encoded by the ABR gene. In humans, the canonical protein has a reported length of 859 amino acid residues and a mass of 97.6 kDa. Its subcellular localization is in the cell projections. Alternative splicing is reported to yield 4 different isoforms for this protein. It is noted to be involved in GTPase activation and GPCR signaling pathways. Other names for this target antigen include active breakpoint cluster region-related protein, ABR, RhoGEF and GTPase activating protein, active BCR-related, and MDB. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.