Active sliding between cytoplasmic microtubules
Active sliding between cytoplasmic microtubules
复制标题
细胞质微管之间的主动滑动
作者：
M. Koonce;Judy Tong;U. Euteneuer;M. Schliwa
Microtubules are versatile cellular polymers that play a role in cell shape determination and mediate various motile processes such as ciliary and flagellar bending, chromosome movements and organelle transport1. That a sliding microtubule mechanism can generate force has been demonstrated in highly ordered structures such as axonemes2,3, and microtubule-based force generation almost certainly contributes to the function of mitotic and meiotic spindles4,5. Most cytoplasmic microtubule arrays, however, do not exhibit the structural regularity of axonemes and some spindles, and often appear disorganized. Yet many cellular activities (such as shape changes during morphogenesis6–9, axonal extension10,11 and spindle assembly) involve highly coordinated microtubule behaviour and possibly require force generated by an intermi-crotubule sliding mechanism, or perhaps use sliding to move microtubules rapidly into a protrusion for stabilization12. Here we show that active sliding between cytoplasmic microtubules can occur in microtubule bundles of the amoeba Reticulomyxa. A force-producing mechanism of this sort could be used by this organism to facilitate the extension of cell processes and to generate the dynamic movements of the cytoplasmic network.
