Stabilizes the ATG5-ATG12 conjugate (By similarity). The ATG5-ATG12/ATG16 complex is required for efficient promotion of ATG8-conjugation to phosphatidylethanolamine and ATG8 localization to the pre-autophagosomal structure (PAS) (By similarity). Recruits also ATG3 to the PAS (By similarity). Involved in endoplasmic reticulum-specific autophagic process and is essential for the survival of cells subjected to severe ER stress (By similarity). Autophagy is required for proper vegetative growth, asexual/sexual reproduction, and full virulence (PubMed:28894236). Autophagy is particularly involved in the biosynthesis of deoxynivalenol (DON), an important virulence determinant (PubMed:28894236). Homodimer (By similarity). Part of the ATG5-ATG12/ATG16 complex (By similarity). Several units of each may be present in this complex (By similarity). Interacts directly with ATG12 (By similarity). Does not significantly decrease the growth rate under nutrient-rich conditions (PubMed:28894236). Strongly reduces conidiation (PubMed:28894236). Causes only mild infection in point-inoculated spikelets of flowering wheat heads and impairs the spreading to nearby spikelets (PubMed:28894236). Reduces also strongly the production of deoxynivalenol (DON), an important virulence determinant (PubMed:28894236). Belongs to the ATG16 family.