UBTD1 promotes association between YAP and β-TrCP to induce YAP ubiquitylation. (A) Co-IP of endogenous YAP and UBTD1 in Hep3B and Huh7 cells. YAP was used as a bait. The IgG isotype was used as a negative control. (B) Co-IP of endogenous YAP and UBTD1 in Hep3B and Huh7 cells. UBTD1 was used as a bait. The IgG isotype was used as a negative control. (C) Co-IP of endogenous β-TrCP, UbcH5c, and UBTD1 in Hep3B and Huh7 cells. UBTD1 was used as a bait. IgG isotype was used as a negative control. (D) Co-IP of endogenous β-TrCP, UbcH5c, and YAP in Hep3B and Huh7 cells. Hep3B and Huh7 cells were transfected with the UBTD1 shRNA. β-TrCP was used as a bait. IgG isotype was used as a negative control. Immunoblot of UBTD1 shows the level of shRNA-mediated depletion. (E) Co-IP in Hep3B and Huh7 cells between endogenous β-TrCP, UbcH5c, and YAP. Hep3B and Huh7 cells were transfected with the UBTD1overexpression vector. β-TrCP was used as a bait. (F) YAP ubiquitination was detected by Western blotting. UBTD1 overexpression markedly promoted YAP ubiquitination.