FIG. 5.

ShcV interacts with the N-terminal third of HopPtoV in LexA yeast two-hybrid assays, with the strongest binding occurring between amino acids 76 and 125 of HopPtoV. (A) Schematic representation of the HopPtoV fragments that were fused to the DNA-binding domain (DBD) and used in the LexA yeast two-hybrid interaction assay. The top white box represents the full-length HopPtoV protein (391 amino acids). The lower black bars represent a series of HopPtoV fragments that were fused to the DBD and tested in the yeast two-hybrid assay to determine if they interacted with ShcV fused to the transcriptional activation domain (AD). A representation of the results is shown: +, strong interaction; −, no detectable interaction; +/−, weak interaction. (B) Yeast strains carrying pJG4-5::shcV (producing AD-ShcV) and pEG202 with different hopPtoV fragments (producing DBD fusions) were grown at 30°C for 2 days on the appropriate selective medium containing X-Gal and either galactose (Gal) or glucose (Glu). Results were scored based on the amount of blue pigmentation produced by the colonies: dark blue, strong interaction; pale blue, weak interaction; and white, no detectable interaction. Analogous experiments measuring the rescue of leucine auxotrophy, the other reporter of this yeast two-hybrid system, showed similar results (data not shown).