Confirmation of HHO1 deletion. Four haploid strains used in this study, with indicated HHO1 status and mating types (α or a), were analyzed for: a the HHO1 gene by PCR analysis, and b Hho1 protein by western blotting. In a the positions and expected sizes of PCR products, containing either the HHO1 open reading frame or the kanMX4 module (boxes), are shown. A DNA ladder (M; Promega) was used for DNA size estimation (kilobase pairs, kbp). In b Hho1 (red) and tubulin (green) staining by western blotting is shown in the upper panel, and general protein staining with Ponceau S is shown in the lower panel. Pre-stained markers (M; Thermo Scientific) were used for molecular weight estimation (kilodaltons, kDa). A subset of these markers was detected as red bands in western blotting. Predicted molecular weights of Hho1 and tubulin are 28 and 50 kDa, respectively (see Saccharomyces Genome Database at http://www.yeastgenome.org).