FIGURE 2.

PS1 mutant, F411Y/S438P, active in the absence of NCT. A and B, cells expressing PS1 wild type, F411Y/S438P (A), F411Y, or S438 (B) mutants, otherγ-secretase subunits, and C1–55-Gal4p were examined for growth after 3 days at 30 °C on selection (SD-LWHUAde) or nonselection (SD-LWU) media, as indicated. C, β-galactosidase activity was measured for each yeast strain containing wild type or mutant PS1, as indicated. The experimental conditions are as in Fig. 1C. Data represent means ± S.D.;n=3. Asterisks indicate p < 0.01 with respect to PS1 wild type. D, cells expressing D385A/F411Y/S438P, the catalytic site mutant, were examined for growth as indicated.