Schematic working model of ESCRT-III function on the PVC/MVB. Four marker proteins, aleurain-GFP, GFP-VIT1, LRR84A-GFP, and EMP12-GFP, reach the LV via the PVC/MVB from secretory or endocytic pathways. The ESCRT-III complex and its regulator SKD1 function on the PVC/MVB to sequester specific membrane cargoes and generate luminal vesicles. ER and TGN are omitted from the model for clarity. CW, Cell wall; LPVC, late prevacuolar compartment. [See online article for color version of this figure.]