FIG. 4.

Homomeric interactions in the two-hybrid system between Gag proteins with CA mutations. (A) β-galactosidase assay. Yeast strain CTY10-5d was transformed with plasmids encoding LexADB-Gag fusions and Gal4AD-Gag fusions. The y axis presents units of β-galactosidase enzyme activity. Results are the averages from four separate yeast clones, and the control represents the interaction between the empty vector and fusion proteins. The error bars represent the standard deviations. The low levels in CA2 and CA3 were almost below detection. WT, wild type. (B) Yeast cell lysates expressing pairs of fusions were analyzed by Western blotting by probing with anti-Gal4 or anti-LexA antibodies. Molecular weights are given in thousands.