A membrane microdomain that forms a necklace around the bulb (crater) of a caveola. Intramembrane particles are concentrated in this region and cytoskeletal components, including actin, are highly enriched in the area underlying it.
caveolar macromolecular signaling complex
cell projection membrane +
cellularization cleavage furrow +
cleavage furrow +
flotillin complex
hinge region between urothelial plaques of apical plasma membrane