FIGURE 6.

Trypsin digestion of TMD-swap PS1 polypeptides in DKO cells. 1% CHAPSO-solubilized lysates prepared from DKO cells transiently transfected with WT PS1 (A) or TMD-swap PS1 mutants (B) were divided into four samples and incubated with trypsin at the indicated concentrations above the panels and analyzed by immunoblotting using the anti-PS1 C terminus antibody (anti-PS-C3). Full-length PS1 (PS1 FL) and CTF are shown by black arrowheads and arrows, respectively. Note that the digestion patterns of mutant PS1 are almost similar, whereas the stability of HMW complex is different (see Fig. 5B).