Fig. 7. Analysis of MDY2 overexpression. (A) Effect of MDY2 overexpression on mating efficiency. Wild-type strain (W303-1A) was transformed with an empty 2 µ vector (pRS426), mdy2 mutant (HZH686) were transformed with 2 µ MDY2 plasmids (pRS426-MDY2). The quantitative mating assay was conducted as described in Materials and Methods. The percentage of diploid cells formed is shown. The data are the means of two independent assays. (B) Halo assay for effect of MDY2 overexpression on -factor production. 1. MAT mdy2 mutant cells (HZH683) with an empty 2 µ vector (pRS426). 2. MAT wild-type cells (W303-1B) with 2 µ MDY2 plasmids (pRS426-MDY2). 3. MATa Wild-type cells (W303-1A). 4. MAT mdy2 mutant cells (HZH683) with 2 µ MDY2 plasmids (pRS426-MDY2). (C) Shmoo index. Wild-type strain W303-1A was transformed with the empty 2 µ vector (pRS426) and the mdy2 mutant (HZH686) was transformed with the 2 µ MDY2 plasmid (pRS426-MDY2) or pRS426. The cultures were grown in SD medium to log phase and then treated with 5 µM -factor. Samples were taken at the indicated times and the numbers of shmoos in samples of at least 300 cells were counted.