FIGURE 9:

Btn2 and Cur1 influence prion propagation indirectly through changes in the availability of Sis1. (A) Low-copy expression plasmids for the expression of mCherry-tagged Nrp1PrD, Rnq1PrD, Sup35PrD, Ure2PrD, or glutamine-expanded huntingtin exon 1 (Q103) were introduced into BY4741 yeast cells that expressed GFP-tagged Btn2 or Cur1 from a plasmid. Fluorescence microscopy was performed at 25°C. (B) Magnification of peripheral aggregates in cells that coexpressed Btn2-GFP and mCherry-tagged Nrp1PrD, Sup35PrD, or Rnq1PrD. (C) Wild-type [NRP1C+] cells or cells in which chromosomal Sis1 was replaced with Sis1ΔDD were incubated at 37°C for 3 d. (D) [NRP1C+] cells were transformed with galactose-regulatable expression plasmids for Sis1 or NLS-Sis1. The transformants were streaked onto galactose plates, incubated for 3 d, transferred onto YPD plates for color development, and photographed.