[Endothelial microtubules as integral part of the mechanism controlling the level of stimulated secretion of van Willebrand factor].
We used double immunofluorescence and electron microscopy to study the spatial relationships between Weibel--Palade bodies (WPBs) and cytoskeletal elements in endothelial cells treated with thrombin or cytoskeleton-damaging agents. We have found that some WPBs undergo translocation towards the centrosome in 5 min in the cells treated with thrombin, cytochalasin B or calyculin A. The cells treated with thrombin or cytochalasin exhibit depletion of WPBs, whereas WPBs found at the cell periphery were colocalized with intermediate filaments. There was a precise colocalization observed between the WPBs and microtubules in the calyculin-treated cells in which all WPBs undergo centrosome-directed translocation within 15 min after the agent addition. When vimentin filaments were induced to collapse by demecolcine, intermediate filaments and WPBs both translocated to the perinuclear region. The data provide the first direct evidence that secretory granules utilize microtubules to move in retrograde direction, i.e., away from the plasma membrane, towards the centrosome. We suggest that anterograde movement of WPBs is dependent on their interaction with vimentin filaments.
Bystrevskaia
V B
VB
Vinogradova
T M
TM
Smirnov
V N
VN
D001011:Aorta / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000378:metabolism* / Q000648:ultrastructure; D006801:Humans; D007382:Intermediate Filaments / Q000378:metabolism; D046529:Microscopy, Electron, Transmission; D008870:Microtubules / Q000378:metabolism* / Q000648:ultrastructure; D021381:Protein Transport / Q000502:physiology; D014746:Vimentin / Q000378:metabolism; D020302:Weibel-Palade Bodies / Q000378:metabolism* / Q000648:ultrastructure; D014841:von Willebrand Factor / Q000378:metabolism*
D014746:Vimentin; D014841:von Willebrand Factor