2025 Volume 65 Issue 1 Pages 4-8
The plasma membrane has protrusions and invaginations. The protrusions are filopodia, lamellipodia, and so on, and the invaginations are clathrin-coated pits, caveolae, and so on. The specific shape of these membrane protrusions and invaginations are made by the actin cytoskeleton and the fine molds of the membrane, which are BAR domain superfamily proteins of ~70 members. The invaginations are cleaved off into intracellular vesicles for endocytosis. Because of the similar molecular architectures, the protrusions are cleaved off into extracellular vesicles in a reminiscent manner as the cleavage of the invagination into the endocytic vesicles.
