Fig. 2. (A) A diagram of specific ubiquitin constructs. (B) HA-Ub and specific mutant ubiquitin constructs were transfected into 293T cells. The cell lysates were immunoprecipitated with an anti-Flag antibody. (C) HA-Ub, Flag-NEDD4, Myc-YOD1, and Myc-YOD1 (C160S) were transfected into 293T cells. An anti-Flag antibody was used to immunoprecipitate Flag-NEDD4. (D) 293T cells were transfected with HA-Ub, specific mutant ubiquitin constructs, and Myc-YOD1. The cell lysates were used with an anti-Flag antibody. (E) To analyze the differential expression of HA-tagged ubiquitin with and without YOD1 expression, densitometric analysis was performed using Image J.