Caveolae, transmembrane signalling and cellular transformation.
Caveolae are approximately 50-100 nm membrane micro-invaginations associated with the plasma membrane of a wide variety of cells. Although they were first identified in transmission electron micrographs approximately 40 years ago, their exact function(s) has remained controversial. Two well-established functions include: (1) the transcytosis of both large and small molecules across capillary endothelial cells and (2) the utilization of GPI-linked proteins to concentrate small molecules in caveolae for translocation to the cytoplasm (termed potocytosis). Recently, interest in a 'third' proposed caveolar function, namely transmembrane signalling, has been revived by the identification of caveolin--a transformation-dependent v-Src substrate and caveolar marker protein--and the isolation of caveolin-rich membrane domains from cultured cells. Here we will discuss existing evidence that suggests a role for caveolae in signalling events.
Lisanti
M P
MP
Whitehead Institute for Biomedical Research, Cambridge, MA 02142-1479, USA.
Tang
Z
Z
Scherer
P E
PE
Kübler
E
E
Koleske
A J
AJ
Sargiacomo
M
M
D015415:Biomarkers / Q000032:analysis; D051242:Caveolin 1; D022461:Caveolins; D002462:Cell Membrane / Q000502:physiology* / Q000648:ultrastructure*; D008565:Membrane Proteins / Q000032:analysis; D015398:Signal Transduction / Q000502:physiology*
D015415:Biomarkers; D051242:Caveolin 1; D022461:Caveolins; D008565:Membrane Proteins