Loosening of a preprophase band of microtubules in onion (Allium cepa L.) root tip cells by kinase inhibitors

Effects of kinase inhibitors on the preprophase band of microtubules in oni on (Allium cepa L.) root tip cells were examined. Bundled microtubules in p reprophase bands were dispersed on the cell cortex when onion seedlings wer e incubated with 2.5-5.0 mM 6-dimethylaminopurine. Fifteen min was enough f or the bundled microtubules to disappear. Although many preprophase bands r emained when the seedlings were incubated with 60 mu M staurosporin, these preprophase band microtubules were loosened and the width of the band becam e broad. These results suggest that some kinases are involved in the microt ubule bundling in the preprophase band development.