Phospholipid scramblase involved in autophagy by mediating autophagosomal membrane expansion (PubMed:
22456507, PubMed:
27510922, PubMed:
29437695, PubMed:
32513819, PubMed:
33468622, PubMed:
33850023, PubMed:
32610138, PubMed:
33106659). Cycles between the preautophagosomal structure/phagophore assembly site (PAS) and the cytoplasmic vesicle pool and supplies membrane for the growing autophagosome (PubMed:
16940348, PubMed:
22456507, PubMed:
33106659). Lipid scramblase activity plays a key role in preautophagosomal structure/phagophore assembly by distributing the phospholipids that arrive through ATG2 (ATG2A or ATG2B) from the cytoplasmic to the luminal leaflet of the bilayer, thereby driving autophagosomal membrane expansion (PubMed:
33106659). Also required to supply phosphatidylinositol 4- phosphate to the autophagosome initiation site by recruiting the phosphatidylinositol 4-kinase beta (PI4KB) in a process dependent on ARFIP2, but not ARFIP1 (PubMed:
30917996). In addition to autophagy, also plays a role in necrotic cell death (By similarity).