Lipid transfer protein involved in autophagosome assembly (PubMed:21645148). Tethers the edge of the isolation membrane (IM) to the endoplasmic reticulum (ER) and mediates direct lipid transfer from ER to IM for IM expansion (By similarity). Binds to the ER exit site (ERES), which is the membrane source for autophagosome formation, and extracts phospholipids from the membrane source to the IM for membrane expansion (By similarity). Plays an essential role in plant nutrient recycling (PubMed:21645148, PubMed:19773385). Involved in the negative regulation of plant defense responses to biotrophic pathogens (PubMed:21645148). Involved in a negative feedback loop that modulates NPR1-dependent salicylic acid (SA) signaling and limits senescence and immunity-related programmed cell death (PCD) in plants (PubMed:19773385). Involved in the degradation of damaged peroxisomes (PubMed:24368788). a 1,2-diacyl-sn-glycero-3-phospho-L-serine(in) = a 1,2-diacyl-sn-glycero-3-phospho-L-serine(out) a 1,2-diacyl-sn-glycero-3-phosphoethanolamine(in) = a 1,2-diacyl-sn-glycero-3-phosphoethanolamine(out) Early senescence phenotype (PubMed:21645148, PubMed:19773385, PubMed:24368788). Defects in autophagosome formation. Enhanced resistance to powdery mildew (Golovinomyces cichoracearum) and mildew-induced cell death. Constitutive expression of defense-related genes (PubMed:21645148). Increased number of peroxisomes and accumulation of peroxisomal proteins (PubMed:24368788). Reduced sensitivity to programmed cell death (PCD) induced by both hydroxyurea and the bacterial avirulent factor avrRpm1 (PubMed:24285797). Belongs to the ATG2 family. Was originally thought to correspond to two different genes. Was originally thought to correspond to two different genes.