FIG 2.

The WD40 repeat region of UAF1 is required for interaction with USP12 and USP46. (A) Schematic representation of truncated UAF1 proteins. The WD40 repeat region of UAF1 is indicated by a black box; and the two SUMO-like domains (SLD1 and SLD2) are indicated by gray boxes. The results obtained with USP12 and USP46 are summarized on the right (++, strong binding; +, weak binding; −, no binding). Also summarized are the results that we previously obtained with HPV E1 (21). (B) Coimmunoprecipitation mapping assay. The indicated 3F-UAF1 truncated proteins were expressed in C33A cells together with RFP-USP12 or RFP-USP46 and immunoprecipitated using an anti-Flag antibody. The presence of RFP-USPs in the immunoprecipitates was determined by Western blotting with an anti-RFP antibody. The results for input cell extracts (IN) are shown at the bottom. (C) Colony formation assay. C33A cells were transfected with expression vectors encoding the indicated UAF1 proteins and grown for approximately 3 weeks in G418-containing medium. Colonies were fixed with methanol and stained with methylene blue.