TRIM20 interacts with ULK1 and Beclin 1. (A and B) Coimmunoprecipitation analysis of GFP-TRIM20 (T20) with Myc-ULK1 (A) or Flag-Beclin 1 (B) in HEK293 cells extracts. IP, immunoprecipitation; WB, Western blot. (C) Confocal microscopy of HeLa cells coexpressing mCherry-TRIM20 with GFP-ULK1. Line tracing corresponds to arrow. White outline, cell boundary defined by background fluorescence. Insets, enlarged areas as indicated by white outlined squares. Bars, 10 µm. (D) Coimmunoprecipitation analysis of TRIM20 complexes with p-ULK1 (Ser-317) in HEK293 cells. (E) TRIM20 domains and deletion constructs used. Dotted lines, deleted regions. (F) Coimmunoprecipitation analysis of interactions between deletion variants of TRIM20 (as GFP fusions) with Myc-ULK1 in HEK293 cells. (G) GST pull-down analysis of radiolabeled Myc-ULK1 with GST-tagged deletion variants of TRIM20. (top) Autoradiogram of pull-down products. (bottom) Coomassie brilliant blue (CBB)–stained SDS-polyacrylamide gel with GST ­deletion variants of TRIM20. Data are representative of three or more experiments.