FIG. 9.

The GPPX3Y-containing TEX14 region interacts with CEP55 much more strongly than the equivalent regions of ALIX and TSG101 and inhibits the CEP55-ALIX and CEP55-TSG101 interactions. The pcDNA3 vectors lacking an insert (Empty) or containing the truncated TEX14 (TX), ALIX (ALIX), TSG101(TSG), and TEX14 mutant (AAAX3A) were cotransfected into HEK293T cells, along with VP16-AD-X, GAL4-BD-Y, and GAL4.3.1-mCherry vectors indicated at the bottom of each panel. The GAL4-BD-Y vector, containing the Renilla luciferase sequence, was replaced by yellow fluorescent protein (YFP) sequence. YFP expression was used for normalization of transfections instead of Renilla luciferase. The relative interaction of proteins X and Y is determined by the mCherry/YFP ratio. The interactions of chimeric VP16-AD-X and GAL4-BD-Y proteins in transfected HEK293T cells are shown (see Fig. 6B and Table 2 for additional details).