Figure 1.

CUL3 interacts with BECN1. (A) BECN1 protein or mRNA downregulation overlap in different tumor samples. (B) The low expression of BECN1 was not due to the transfectional repression or gene copy number deletion. (C) HeLa cells were treated with the indicated inhibitors for 24 h and immunoblotting was performed. (D) 231 cells were treated with indicated concentration of MG132 for 24 h and the protein extracts was subjected to immunoblotting. (E) 293 t cells transfected with plasmids encoding Flag-BECN1, treated with 10 μM MG132 for 6 h, and the BECN1 immunoprecipitation were subjected to SDS-PAGE and then analyzed by mass spectrum. The peptide fragment of CUL3 was shown. (F) 293 t cells were transfected with indicated plasmids, the immunoprecipitation was performed by using Flag affinity gels or anti-MYC-tag antibody, and then bloted for the indicated proteins. (G) The illustration of BECN1 deletion mutants. (H) The binding site of BECN1 and CUL3 is near BH3 domain. 293 t cells were transfected with indicated plasmids, the immunoprecipitation of Flag affinity gels was subjected to immunoblotting assay