Figure 4.

Mapping of the Grb2-binding site of NS5A by two-hybrid analysis. NS5A deletion and point mutants were constructed in pGAD425, and their interaction with BD-Grb2 was tested as described in Fig. 3A. Schematic representation of NS5A mutant proteins is not depicted to scale. Numbers represent terminal aa positions of the NS5A sequence. A summary of Grb2- and PKR-binding activities of NS5A variants is shown on the right. The data indicated here in italics are predicted from previous results (16). Top bar indicates the region required for PKR interaction. ISDR, IFN sensitivity-determining region; −, no growth on SD medium −His; +, growth on the selective medium.