Topical aspects of vacuolar protein transport: Autophagy and prevacuolar compartments

For many plant researchers protein transport to the vacuole is primarily a question of the mechanisms underlying the recognition of vacuolar proteins and their segregation in the Golgi apparatus from other products of the secretory pathway. Autophagy is an alternative process by which proteins can enter the vacuole. Examples of apparent selective autophagy are seen in cereal grains depositing storage proteins, and in rubber particle sequestration. Non-selective autophagy is observed during starvation and in senescing tissues. Another overlooked aspect of vacuolar protein transport involves the participation of prevacuolar sorting compartments, some of which may function as endosomes.