The N-terminal 278 amino acids of UL97 contain the minimal 14-3-3 binding domain.A, schematic representation of the truncated forms of UL97 used in this study. B, U-2 OS cells were transfected with an expression vector for the indicated HA-tagged UL97 fragment (FL, full length; N1, C1, N2, C2, truncated forms) or an empty vector (−) together with expression vectors for the indicated Flag-tagged 14-3-3 isoform. After 48 h, lysates (Input) were harvested, subjected to immunoprecipitation with anti-HA antibody (IP: anti-HA), and analyzed by Western blot with the indicated antibodies. For all panels, representative images from one of three independent biological replicates are shown.