Probable sterol 3-beta-glucosyltransferase that mediates autophagic degradation of peroxisomes (pexophagy) (PubMed:11856375, PubMed:14585290, PubMed:12839986, PubMed:19605559). Also required for cytoplasm to vacuole transport (Cvt) and autophagic degradation of mitochondria (mitophagy) and nuclei (nucleophagy) (By similarity). a sterol + UDP-alpha-D-glucose = a sterol 3-beta-D-glucoside + H(+) + UDP The first GRAM domain is required for association with the micropexophagic apparatus (PubMed:12839986). Belongs to the glycosyltransferase 28 family.