TRIM20 interacts with mammalian Atg8 paralogues (mAtg8s). (A) GST pull-down analysis of interactions between radiolabeled Myc-TRIM20 and GST-tagged mAtg8s. (top) Autoradiogram of pull-down products. (bottom) CBB-stained SDS-polyacrylamide gel with GST-mAtg8s. (B) TRIM20 domains and deletion constructs used. (C) GST pull-down analysis of binding between radiolabeled Myc-TRIM20 deletion variants and GST-GABARAP and GST-LC3A. (D) Identification of GABARAP-interacting regions on TRIM20 by peptide array. Three series of TRIM20 peptides (regions of primary sequence staggered by three amino acid residues), with either three or four positive consecutive binding signals, were identified. The peptide sequences corresponding to the positive binding signals (encompassed spots; defined as regions I, II, and III) were mutated as indicated and were subjected to the GST pull-down experiments in E and Fig. S2 F. (E) GST pull-down analysis of interaction between radiolabeled Myc-TRIM20 triple mutants and GST-GABARAP. Data are representative of three or more experiments.