Essential for vacuolar protein sorting. Required for vacuole biogenesis, stability and to maintain vacuole morphology. Required for growth at elevated temperatures. Acts as component of the HOPS complex that acts during the docking stage of vacuole fusion. HOPS is an effector for the vacuolar Rab GTPase YPT7 and is required for vacuolar SNARE complex assembly. It remains bound to SNARE complexes after vacuole fusion. Component of the HOPS complex which is composed of PEP5, VPS16, PEP3, VPS33, VPS39 and VPS41. HOPS associates with phosphoinositides and the PX domain of VAM7. Interacts with VAM7. Present with 1300 molecules/cell in log phase SD medium. Belongs to the VPS16 family.