Figure 2.

Crystal structures of the Atg8 family members and ubiquitin. All Atg8s share a similar ubiquitin-like fold with two additional amino-terminal α helices. GATE-16 is shown in blue (Protein Data Bank (PDB): 1EO6), GABARAP in green (PDB: 1KOT), LC3B in red (PDB: 1V49) and ubiquitin in gray (PDB: 1UBI). Helix shape represents an α helix; arrow shape represents a β sheet; arrowhead represents the carboxyl termini of β sheets.