Dual control of caveolar membrane traffic by microtubules and the actin cytoskeleton

摘要: Live cell, time-lapse microscopy was used to study trafficking of caveolin-1-GFP in stably expressing CHO cells. Multiple cytological and biochemical tests verified that a reliable marker for endogenous caveolin-1. At steady state, most either at the cell surface associated with invaginated caveolae or near centrosome caveosomes. fluorescence imaging indicated while much relatively sessile, numerous, highly motile caveolin-1-GFP-positive vesicles were present within interior. These moved speeds ranging from 0.3-2 μm/second movement abolished when microtubules depolymerized nocodazole. In absence microtubules, increased more than twofold they became organized into linear arrays. Complete depolymerization actin cytoskeleton latrunculin A, by contrast, triggered rapid massive movements caveolin-positive structures towards centrosomal region cell. The caveolar membrane system cells therefore appears be comprised three caveolin-1-containing compartments. include are confined cortical filaments, peri-centrosomal caveosomes vesicles, which we call `cavicles9, move constitutively bi-directionally along between behavior cavicles suggests function as transport intermediates