Required for autophagy. Conjugation to ATG12 is essential for plant nutrient recycling (PubMed:16040659). 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 complete proteolysis of chloroplast stroma proteins in senescent leaves (PubMed:23327451). Involved in the degradation of damaged peroxisomes (PubMed:24463818). Conjugated to ATG12. Ubiquitous. Conjugated to ATG12; which is essential for autophagy. Conjugation with ATG12 involves ATG7 as an E1-like activating enzyme and ATG10 as an E2-like conjugating enzyme (By similarity). Mutant plants are hypersensitive to nitrogen or carbon starvation (PubMed:16040659). Early senescence phenotype (PubMed:16040659, PubMed:19773385). Hyper accumulation of salicylic acid (SA) (PubMed:19773385). Increased number of peroxisomes and accumulation of peroxisomal proteins (PubMed:24463818). Belongs to the ATG5 family.