Fig. 3
Effect of various protease inhibitors on CTF-PS1 and CTF-PS2 immunoreactivity in HEK293 transfected cells. Stably transfected HEK293 cells expressing CTF-PS1 (A, C) or CTF-PS2 (B, C) were incubated for 5 hr in the presence of the proteasome inhibitors Z-IE(Ot-Bu)A-leucinal (ZIE, 2.5 × 10−5M) and lactacystin (5 × 10−6M) or with trans-epoxysuccinyl-l-leucylamido-(4-guanidino) butane (E64, 10−4M), 4-(2-amido-ethyl) benzenesulfonyl fluoride (AEBSF, 10−4 M), phosphoramidon (10−5 M), pepstatin A (10−5 M), and Z-L-Leucinal (ZL, 2.5 × 10−5 M). Cells were lysed, then immunoreactivity of CTF-PS was revealed with αPS1Loop and αPS2Loop antibodies as described in Materials and Methods.