Ubiquitination and Degradation of the Hominoid-Specific Oncoprotein TBC1D3 Is Mediated by CUL7 E3 Ligase
Figure 3
CUL7 mediates the degradation and ubiquitination of TBC1D3.
(A) CUL7 increased TBC1D3 ubiquitination. HeLa cells were transfected with Myc-TBC1D3 and with or without HA-CUL7. TBC1D3 was immunoprecipitated with anti-Myc antibody. Polyubiquitination of TBC1D3 was analyzed by immunoblotting, using anti-ubiquitin antibody. (B) CUL7 expression enhances TBC1D3 degradation. HeLa cells were transfected with Myc-TBC1D3 and with or without HA-CUL7. Cells were starved for 3 h and stimulated with 10% FCS. Lysates were separated by SDS-PAGE and immunoblotted with anti- TBC1D3, CUL7 and tubulin antibodies. (C) Summary of results. Mean ± SE of 3 independent experiments. TBC1D3 expression is normalized by tubulin. The initial level of TBC1D3 expression in each group is set to 100%.
