Transferrin receptor cycling by human lymphoid cells: lack of effect from inhibition of microtubule assembly.
Flow cytometry was used to follow the uptake and release of fluorescein-conjugated ferro-transferrin by CCRF-CEM human T - leukaemia cells on an individual cell basis. Pretreatment with the stathmokinetic agent vincristine for 5 hr had no effects on the cycling of transferrin, although microscopic examination of the cells showed a substantial proportion to be arrested in metaphase with cytoplasmic dispersal of tubulin, indicating inhibition of microtubule assembly. Tubulin is therefore unlikely to play a major role in the transferrin cycle of exponentially-growing cells, despite earlier reports that the cytoskeleton is involved in receptor clustering and down regulation.
D002453:Cell Cycle / Q000187:drug effects; D002460:Cell Line; D004705:Endocytosis; D005089:Exocytosis; D006801:Humans; D008870:Microtubules / Q000187:drug effects; D011956:Receptors, Cell Surface / Q000502:physiology*; D011990:Receptors, Transferrin; D014168:Transferrin / Q000502:physiology*; D014404:Tubulin / Q000378:metabolism; D014750:Vincristine / Q000494:pharmacology*
D011956:Receptors, Cell Surface; D011990:Receptors, Transferrin; D014168:Transferrin; D014404:Tubulin; D014750:Vincristine