Structure and expression of wtTax-1, wtTax-2, and their mutant proteins. (A) Schematic representation of the Tax-1 (gray) and Tax-2A (black) constructs used in this study. The amino acid length of the proteins and sequence of the Tax-1 PBM (ETEV) are indicated. (B) Western blot of Tax-1 and Tax-2 expressed in transiently transfected 293T cells. Proteins were detected using rabbit Tax-1/Tax-2–specific antisera.