Severing at sites of microtubule crossover contributes to microtubule alignment in cortical arrays

摘要: The cortical microtubule (MT) array and its organization is important in defining the growth axes of plant cells. In roots, MT exhibits a net-like configuration division zone, densely-packed transverse alignment elongation zone. This transition essential for anisotropic cell expansion consequently has been subject intense study. Cotyledons exhibit pavement cells predominantly aligned petioles, provide an excellent system determining basis organization. We show that both kinds array, growing MTs frequently encounter existing MTs. Although some steep-angled encounters result catastrophes, most frequent outcome these successful negotiation by to form crossover. Surprisingly, such similar arrays. contrast, arrays much higher frequency severing events compared with Severing occur almost exclusively at sites where cross over one another. process crossover results removal unaligned MTs, likely difference between array.