GTPase activator for the nuclear Ras-related regulatory protein RAP-1A (KREV-1), converting it to the putatively inactive GDP-bound state.
Subcellular locations: Cytoplasm, Cytoplasm, Perinuclear region
Isoform 1 and isoform 2 are expressed in platelets with isoform 2 being the predominant form. Expressed in lymphocytes, heart, testis and pancreas.