Required for cytoplasm to vacuole transport (Cvt), pexophagy and mitophagy. Also involved in endoplasmic reticulum-specific autophagic process and is essential for the survival of cells subjected to severe ER stress. Functions in protein retrieval from the endocytic pathway. Required for proper sorting of the v-SNARE protein SNC1. Forms a complex with SNX4 and ATG17. The PX domain binds phosphatidylinositol 3-phosphate which is necessary for peripheral membrane localization of ATG20 to the perivacuolar punctate structures. Present with 358 molecules/cell in log phase SD medium. Belongs to the sorting nexin family.