Component of the vacuolar transporter chaperone (VTC) complex, which plays a role in vacuolar membrane fusion (By similarity). Involved in the control of cell polarity. The VTC complex is an integral membrane heterooligomer composed of at least vtc1, vtc2 and vtc4 (By similarity). Interacts with GTP-bound Ras-like cdc42, which is subsequently inactivated. Belongs to the VTC1 family.