RAB4A is a member of the small GTPase superfamily. RAB4A interacts with STX4, RAB11FIP1, RABEP1, CD2AP and KIF3B. In addition, Rab4 is involved in the translocation of glucose transporter (Glu4) in adipocytes in response to insulin. Rab4 overexpression causes a redistribution of receptors on plasma membrane versus endocytic compartments.