Reclustering of scattered Golgi elements occurs along microtubules
Ho, W.C.; Allan, V.J.; van Meer, G.; Berger, E.G.; Kreis, T.E.
European Journal of Cell Biology 48(2): 250-263
1989
ISSN/ISBN: 0171-9335 PMID: 2743999 Document Number: 340918
Depolymerization of the interphase microtubules by nocodazole results in the scattering and apparent fragmentation of the Golgi apparatus in Vero Fibroblast cells. Upon removal of the drug, the interphase microtubles repolymerize, and the scattered and apparent fragmentation of the Golgi apparatus in Vero fibroblast cells. Upon removal of the drug, the interphase microtubules repolymerixe, and the scattered Golgi elements move back to the region around the microtubule-organizing center (mTOC) within 40 to 60 min. Using a fluorescent lipid analogue (C6-NBD-ceramide) as a vital stain for the scattered Golgi elements, their relocation was visualized by video-enhanced fluorescence microscopy in Vero cells maintained at 20.degree. C. The NBD-labeled structures were identified as Golgi elements by their colocalization with galactosyltransferase in the fixed cells. During reclustering, NBD-labeled Golgi elements were observed to move by discontinuous saltations towards the MTOC with velocities of 0.1 to 0.4 7m/s. Paths along which Golgi elements moved were superimposable on microtubules visualized by indirect immunofluorescence. Neither the collapse of intermediate filaments caused by microinjection of antibodies to vimetin nor the disruption of microfilaments by cytochalasin D had an effect on the reclustering of Golgi elements or the positioning of the Golgi apparatus. These data show that scattered Golgi elements move along microtubles back to the region around the MTOC, while neither intact intermediate filaments nor microfilaments are involved.