Skip to main content
. 2011 Sep;31(18):3700–3709. doi: 10.1128/MCB.05448-11

Fig. 4.

Fig. 4.

TSC-22 attenuates Smad7/Smurf-induced TβRI ubiquitination and degradation. (A) TSC-22 inhibits Smurf1/2-induced ubiquitination of TβRI. HEK293T cells transfected with the indicated constructs (2 μg each) were treated with 50 μM MG132 for 4 h before being harvested for precipitation with nickel beads followed by anti-HA immunoblotting. (B) TSC-22 attenuates Smad7/Smurf-induced turnover of TβRI. HEK293T cells were transfected with the indicated constructs, treated with 50 μg/ml cycloheximide (CHX) for the indicated time periods, and then harvested for anti-HA immunoblotting. The results were quantified by the use of Bandscan software. (C) TSC-22 knockdown enhances the association of Smad7 with TβRI. HEK293T cells were transfected with nonspecific or TSC-22 shRNA, treated with 100 pM TGF-β1 for 2 h, and harvested for coimmunoprecipitation. (D) TSC-22 impairs the association of Smad7 with TβRI. At 48 h posttransfection with the indicated constructs, HEK293T cells were harvested for coimmunoprecipitation assays. (E) Smad7 inhibits the association between TβRI and TSC-22. (F) TβRI decreases the binding of TSC-22 to Smad7. (G) TSC-22 associates with TβRI and Smad7 in different complexes. The experiment was performed as described for Fig. 2F. (H) TSC-22 impairs the association of Smurf2 (C716A) with TβRI in HEK293T cells. (F) Association of TSC-22 and Smad7 with TβRI. HaCaT cells treated with 100 pM TGF-β1 for the indicated time were harvested for coimmunoprecipitation assays.