FIG. 5.

Dig1p and Dig2p inhibit Ste12p through interactions with different regions in vivo. (A) Strain WHY4 bearing plasmids pYeDP8-1/2 (vector), pAO003 (Ste12p DBD), and pSTVP/235 (Ste12p DBD-VP16) was cotransformed with YEplac112 (control), pG1T (GAL-DIG1), and pG2T (GAL-DIG2). Cells were grown to mid-log phase, and FUS1-LacZ expression was measured by assaying β-galactosidase (β-gal) activity 2 h after galactose addition. (B) Yeast strains W303-1A (WT), ISY37 (dig1), and MT1147 (dig2) bearing plasmid pSH18-34 (LexA ops-LacZ) were cotransformed with pMHLex (LexA), pIS196 [LexA-Ste12p(1–688)], or pIS182 [LexA-Ste12p(216–688)]. Transcriptional activation by LexA fusions was assayed by measuring β-galactosidase activity in cells grown to mid-log phase.