FIG. 4.

Southern blot analysis of genomic DNAs from S. cerevisiae strains. (A) Construction used to identify the PRO1 or MPR1 gene. Locations of the EcoRI sites are marked. The PRO1 and MPR1 genes are indicated by shaded boxes; arrows show the direction of transcription. (B) Southern hybridization. Five micrograms of yeast genomic DNA from each strain was digested with EcoRI, electrophoresed on an 0.8% agarose gel, transferred onto a nylon membrane, and hybridized with a 1,161-bp fragment for the PRO1 gene (left) and 1,636 bp fragment for the MPR1 gene (right). Lane 1, Σ1278b; lane 2, FH506; lane 3, MB329-17C; lane 4, S288C; lane 5, XU-I. An EcoT14I-BglII digest of λDNA was used as the DNA size standard.