Rho-related BTB domain-containing protein 3 is a protein that in humans is encoded by the RHOBTB3 gene.

RHOBTB3 is a member of the evolutionarily conserved RHOBTB subfamily of Rho GTPases. For background information on RHOBTBs, see RHOBTB1 (MIM 607351).[supplied by OMIM, Apr 2004].
Function: Rab9-regulated ATPase required for endosome to Golgi transport. Involved in transport vesicle docking at the Golgi complex, possibly by participating to release M6PRBP1/TIP47 from vesicles to permit their efficient docking and fusion at the Golgi. Specifically binds Rab9, but not other Rab proteins. Has low intrinsic ATPase activity due to autoinhibition, which is relieved by Rab9.