Lost to translation: when autophagy targets mature ribosomes.

Autophagy and the ubiquitin proteasome system (UPS) mediate the degradation of cellular proteins. However, we are now realizing that autophagy can also be a selective process that degrades various organelles. Peter and co-workers discovered a selective autophagic pathway that targets ribosomes in Saccharomyces cerevisiae. This pathway, which they termed ribophagy, depends on Ubp3 ubiquitin protease and its partner Bre5. This is an important finding, because it suggests that the number of ribosomes can be adjusted to match the needs of the cell.