(caveola) A membrane raft that forms small pit, depression, or invagination that communicates with the outside of a cell and extends inward, indenting the cytoplasm and the cell membrane. Examples include flask-shaped invaginations of the plasma membrane in adipocytes associated with caveolin proteins, and minute pits or incuppings of the cell membrane formed during pinocytosis. Caveolae may be pinched off to form free vesicles within the cytoplasm.

(caveola) A small pocket, vesicle, cave, or recess communicating with the outside of a cell and extending inward, indenting the cytoplasm and the cell membrane. Such caveolae may be pinched off to form free vesicles within the cytoplasm. They are considered to be sites of uptake of materials into the cell, expulsion of materials from the cell, or sites of addition or removal of cell (unit) membrane to or from the cell surface.

(caveola) Small pit, depression, or invagination, such as any of the minute pits or incuppings of the cell membrane formed during pinocytosis, which close and then pinch off to form small, free, fluid filled vesicles or pinosomes in the cytoplasm.

Endocytic/exocytic CELL MEMBRANE STRUCTURES rich in glycosphingolipids, cholesterol, and lipid-anchored membrane proteins that function in ENDOCYTOSIS (potocytosis), transcytosis, and SIGNAL TRANSDUCTION. Caveolae assume various shapes from open pits to closed vesicles. Caveolar coats are composed of CAVEOLINS.