FIG. 7.

The effects of swd2 mutation on transcription initiation. (A) Effect of swd2 mutation on lacZ expression from INO1-lacZ reporter plasmids. The indicated swd2 mutant strains, as well as the set1Δ strain and the isogenic wild-type strains, were transformed with the reporter plasmids, and β-galactosidase activities were assayed as described in Materials and Methods. In each case, duplicate assays of three independent transformants were performed. The value under each strain represents the amount of derepression relative to the activity of wild-type cells. (B) Tethering Swd2 to the promoter region causes transcription repression. The wild-type yeast strain W303 was transformed with plasmid pBTM116-SWD2 (LexA-SWD2), pM1175 (LexA-SAP30), or pBTM116 (LexA vector control) and either reporter plasmid pAJ01(0 LexA) or pCK30(1 LexA). β-Galactosidase activity was quantitated as described for panel A. The graph represents the amount of repression relative to the activity of transformants with vector only.