Figure 8. Some Sis1 activities are important for [PIN⁺] propagation.

[PIN⁺] [psi⁻] cells of strain 930a expressing Rnq1-GFP were transformed by plasmids encoding the mutant Sis1 proteins described in Figure 5. (A) Primary transformant colonies on medium selecting for the plasmids encoding both wild type and mutant Sis1 proteins were assessed for fluorescence. (B) Cells shown in panel (A) were transferred to plates containing uracil and then onto FOA plates to select for cells expressing the only mutant versions of Sis1. Cells from the FOA plates were then assessed for fluorescence. For each set, upper panels are fluorescent images and lower panels show the same cells in bright field. Control [pin⁻] cells carrying one copy of wild type Sis1 are shown on lower right for comparison.