Autophagy and caspase-independent cell death: p19ARF enters the game.

ARF, often localized in the nucleolus, controls the p53 pathway and ribosomal biogenesis. In a recent issue of Molecular Cell, Kimchi and colleagues describe a short mitochondrial form of ARF (smARF), produced by internal initiation of translation, that dissipates mitochondrial membrane potential independently of p53 and Bcl-2 family members and triggers caspase-independent cell death. The prodeath function of smARF is dependent on the induction of autophagy.