Autophagy-related protein 8 (Atg8) is a ubiquitin-like protein required for the formation of autophagosomal membranes. The transient conjugation of Atg8 to the autophagosomal membrane through a ubiquitin-like conjugation system is essential for autophagy in eukaryotes. Even though there are homologues in animals (see for example GABARAP, , GABARAPL2, MAP1LC3A, MAP1LC3B, , and ), this article mainly focuses on its role in lower eukaryotes such as Saccharomyces cerevisiae.