Sterol transport protein; mediates ergosterol integration into the vacuolar membrane with Ncr1p; lipid solubilizer that binds various amphiphilic lipid ligands; acts as an intravacuolar sphingolipid transporter during microlipophagy, supporting phase separation of the vacuolar membrane; targeted to the vacuole via the Vps10p-dependent endosomal vacuolar protein sorting pathway; functional homolog of human NPC2 Niemann-Pick disease type C2 protein; complements mutations in human NPC2