May play a cooperative role in NF2-mediated growth suppression of cells. Interacts with GJA1. Interaction with GJA1 induces its degradation. Interacts via its RUN domain with the C-terminal region of NF2. Interacts with RAB3A, RAB4A, RAB5A, RAB8A, RAB11A, RAP1A, RAP1B, RAP2A, RAP2B and PDCD6I. No interaction with RAB27A (By similarity). Belongs to the small G protein signaling modulator family.