fig2

Figure 2. Overview of exosome biogenesis. Purple arrows indicate membrane internalization, endosome maturation, cargo trafficking, and the routes toward exosome release or lysosomal degradation. Thin black lines connect labels to structures, and gray boxes highlight the three ILV-formation pathways; colored symbols represent schematic membrane components and cargo. Rab27 is used as a collective label for Rab27a and Rab27b. ALIX: Apoptosis-linked gene 2-interacting protein X; ESCRT: endosomal sorting complexes required for transport; ILVs: intraluminal vesicles; MVB: multivesicular body; Rab7: Ras-related protein Rab-7; Rab27: Ras-related proteins Rab-27A and Rab-27B; SNARE: soluble N-ethylmaleimide-sensitive factor attachment protein receptor; t-SNARE: target-membrane-associated SNARE; v-SNARE: vesicle-associated SNARE.