Caveolae can mediate endocytosis, transcytosis, and potocytosis. Our unders
tanding of these processes as well as the elucidation of the molecular mach
inery involved has greatly expanded. In addition, caveolin, a 22 kDa protei
n often associated with caveolae, can promote the trafficking of sterol thr
ough the cytoplasm independent of vesicles. Caveolin also influences the fo
rmation, morphology, and function of caveolae. The ability of caveolae and
caveolin to mediate macromolecular transport directly impacts a variety of
physiological and pathophysiological processes. (C) 2001 Elsevier Science B
.V. All rights reserved.