Apparently, MG132 elevated the stages of AICDc even in the absence of ubiquitination (Fig. 5B, lanes two and 4), supporting the notion that processing by c-secretase is favored for the duration of proteasome inhibition. MCE Company BAX Inhibiting Peptide V5Cycloheximide chase-experiments confirmed that the absence of cytosolic lysine residues rendered C99 far more steady both …