Fig. 2. The ability of N-terminally truncated Sup35p to maintain the [PS1⁺] determinant in the absence of endogenous wild-type Sup35p synthesis. (A) Cell suspensions of individual transformants post-5-FOA selection were plated onto either YEPD (to determine colony colour) or defined medium lacking adenine (–Ade) to test for suppression of the ade2-1 marker. Three independent transformants (a–c) are shown on the –Ade plates. (B) Western blot analysis of either total cell-free extracts (upper panel) or a soluble protein fraction (lower panel; prepared as described in Materials and methods) using an anti-Sup35p polyclonal antibody. Details of the various Sup35p derivatives tested are given in Figure 3.