ULK1 interacts with SQSTM1 and KEAP1. Lysates from HEK293 cells transfected with vectors encoding FLAG-ULK1 (a) or HA-ULK1 (b) together with those expressing MYC-SQSTM1 (a) or FLAG-KEAP1 (b) were subjected to immunoprecipitation with antibodies against FLAG or HA, and the resulting precipitates (IPs) as well as whole cell lysates (WCLs) were subjected to immunoblot analysis using antibodies specific for the indicated proteins. Confocal microscopy analysis of co-localization of F-ULK1 and either H- KEAP1 (c) or H-SQSTM1 (d) Nuclei were stained with DAPI, and representative single optical sections and merge images are shown. Scale bars: 10 μm. Lysates from HEK293 cells transfected with deletion constructs of M-SQSTM1 (e) or KEAP1 (f) were subjected to immunoprecipitation with antibodies specific for FLAG, and the resulting IPs and WCLs were subjected to immunoblot analysis using antibodies specific for the indicated proteins. (g) Lysates from HEK293 cells transfected with F-ULK1, H-KEAP1, and M-SQSTM1 were subjected to immunoprecipitation with antibodies to HA, and the resulting IPs and WCLs were subjected to immunoblot analysis using antibodies specific for the indicated proteins. (h) Lysates from Ulk1 WT or ulk1 KO MEF cells were subjected to immunoprecipitation with antibodies to SQSTM1, and the resulting IPs and WCLs were subjected to immunoblot analysis using antibodies specific for the indicated proteins.