The protective role of yeast Cathepsin D in acetic acid-induced apoptosis depends on ANT (Aac2p) but not on the voltage-dependent channel (Por1p)

We have previously shown that the yeast Cathepsin D (CatD) Pep4p translocates from the vacuole to the cytosol during acetic acid-induced apoptosis and is required for efficient mitochondrial degradation, though its specific role in this process is still elusive. Here, we show that the protective role of Pep4p in acetic acid-induced apoptosis depends on its catalytic activity and is independent of the yeast voltage-dependent anion channel Por1p (which has no role on mitochondrial degradation) but dependent on AAC proteins, the yeast adenine nucleotide translocator. Our results demonstrate a differential interplay between yeast vacuolar CatD and mitochondrial proteins involved in apoptosis regulation.

► The vacuolar yeast CatD Pep4p protects cells from acetic acid-induced apoptosis. ► Pep4p underlies acetic acid-induced mitochondrial degradation. ► We assessed if the anti-apoptotic role of Pep4p depended on mitochondrial proteins. ► We show Pep4p’s protective role depends on catalytic activity and AAC but not Por1p. ► We suggest CatD differentially interplays with mitochondrial apoptotic regulators.