FIG. 3.

In vivo baiting assays with Rep1p and Rep2p or their GFP fusion derivatives. Abbreviations: R1, Rep1p; R2, Rep2p; VB, vector containing LexA without Rep fusion; VA, vector containing the transcriptional activation domain without Rep fusion; VP, positive control vector in which the constitutive ADH promoter controlled the expression of the LexA-GAL4 fusion; VN, negative control vector in which LexA fused to a transcriptionally inert protein, Drosophila bicoid, was expressed from the GAL1 promoter. For a given binary protein combination, the protein listed before the plus sign was the bait (fused to LexA), and the protein following the plus sign was the suspected prey (fused to the activation domain). The β-galactosidase units shown in the lower panel were obtained in a variation of the dihybrid assay by using lacZ as the reporter gene. The Western blots (lower right panel) were probed with a monoclonal LexA antibody for the bait proteins and with a polyclonal antiserum to the HA1 epitope for the prey proteins.