[Possible role of centrioles in stabilizing cytoplasmic microtubules]

Small fragments of the peripheral cytoplasm were obtained from cytochalasine B-treated mouse embryo fibroblasts and studied for distribution of microtubules by indirect immunofluorescence. Microtubules were demonstrated to progressively depolymerize in these fragments which did not contain any tubules after 6 hours of incubation in the growth medium. This effect was specific for microtubules, since the distribution of intermediate filaments remained unchanged during incubation. The fragments remained viable during incubation, inasmuch no changes were detectable in the membrane potential of the mitochondria stained with rhodamine 123. Progressive destruction of microtubules in the tiny cell fragments is likely to be related to the lack of centrioles in such fragments.