Protein Transport from the Cytoplasm into the Vacuole

The fungal vacuole is integrally involved in various cellular processes that include protein and organellar degradation and recycling. The ability to sequester numerous hydrolases within the cell makes the hydrolytic capacity of the vacuole critical under certain environmental conditions. Accordingly, cellular constituents destined for degradation are delivered to the vacuole through the secretory pathway, by endocytosis and from the cytoplasm. Different mechanisms have evolved to accommodate these multiple transport pathways. Protein transport from the cytoplasm into the vacuole in particular relies on the dynamic nature of the vacuole membrane. This review describes recent research on this topic from yeast systems and points out the direction of future studies aimed at understanding this complex organelle. Received: 13 January/Revised: 9 March 1997