Fig. 7

Fig. 7

Ab-SPOP_DDmutation and Ab-SPOP_{3-box mutation} do not deplete nuclear H2B-GFP.

293TetOn cells expressing H2B-GFP were transfected with vector expressing Ab-SPOP, Ab-SPOP_DDmutation, or Ab-SPOP_{3-box mutation} from a bi-directional TRE promoter. (a) Ab-SPOP causes depletion of nuclear H2B-GFP in cells expressing TagRFP (yellow arrowheads). (b) Ab-SPOP_DDmutation does not cause depletion of nuclear H2B-GFP in cells expressing TagRFP (yellow arrowheads). This suggests that the Ab-SPOP dimerization domain is necessary for the depletion of H2B-GFP. (c) Ab-SPOP_{3-box mutation} does not cause depletion of nuclear H2B-GFP in cells expressing TagRFP (yellow arrowheads). This suggests that the Ab-SPOP 3-box domain is necessary for nuclear depletion of H2B-GFP. The 3-box domain is required for binding with Cul3 in the CRL3 E3 ligase complex¹⁴, indicating that Ab-SPOP interacts with Cul3 protein for its E3 ubiquitin ligase activity.